Topics in nutrition and food science. Dr M. Altamimi 1.

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Topics in nutrition and food science.

Dr M. Altamimi

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Characteristics of Modern life

• Urbanisation• Ready to eat food, fast food and processed

food.• High calories (fat and carbohydrate) low fibre.• Low in vitamins and minerals.• Packaging. Not natural preservation.• Refrigeration and freezing.• Less physical activity.

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• Office based jobs.• Chronic diseases, obesity etc.• Aging, people live longer.

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• Diet – together with physical exercise – plays a major role when we try to prevent or postpone the onset of chronic conditions such as the metabolic syndrome.

• The food industry has already reacted to this challenge and a large number of products have been either reformulated or re-positioned to meet the current need for healthier foods.

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WHO• Chronic diseases are diseases of long duration

and generally slow progression. Chronic diseases are by far the leading cause of mortality in the world, representing 63% of all deaths. 36 million people died from chronic disease in 2008.

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Noncommunicable diseases• Cardiovascular diseases account for most NCD

deaths, or 17 million people annually, followed by cancer (7.6 million), respiratory disease (4.2 million), and diabetes (1.3 million). These four groups of diseases account for around 80% of all NCD deaths, and share four common risk factors:

• tobacco use • physical inactivity • the harmful use of alcohol and • poor diets.

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Bad habits

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Stages of life and R F

In the uterus: • intrauterine growth retardation (IUGR); • premature delivery of a normal growth for

gestational age fetus• over nutrition in utero• Intergenerational factors.

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Infancy:• Retarded growth in infancy can be a reflected in a failure to

gain weight and a failure to gain height. Both retarded growth and excessive weight or height gain can be factors in later incidence of chronic disease. Such as CVD

• There is increasing evidence that among term and pre-term infants, breastfeeding is associated with significantly lower blood pressure levels in childhood.

Consumption of formula instead of breast milk in infancy has also been shown to increase diastolic and mean arterial blood pressure in later life. Obesity

(type 1 diabetes, coeliac disease, some childhood cancers, inflammatory bowel disease) have also been associated with infant feeding on breast-milk substitutes and short-term breastfeeding

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Childhood • low growth in childhood and an increased risk of

CHD has been described, irrespective of size at birth.

• Relative weight in adulthood and weight gain have been found to be associated with increased risk of cancer of the breast, colon, rectum, prostate and other sites.

• Higher blood pressure in childhood (in combination with other risk factors) causes target organ and anatomical changes that are associated with cardiovascular risk, including reduction in artery elasticity.

• High blood pressure in children is strongly associated with obesity,

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Most chronic diseases are present at later period of life - the result of interactions between multiple disease processes as well as more general losses in physiological functions (due to risk factors)

= lack of oxygen and adapted metabolism.

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Angiogenesis

• Angiogenesis is a process of new blood vessel growth that occurs in the human body at specific times in development and growth.

• Although crucial for embryonic development and wound healing, angiogenesis also contributes to disease, such as in the growth of solid tumors, chronic inflammation, atherosclerosis, ischemia, and diabetic retinopathy.

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Inducers• A number of inducers of angiogenesis have

been identified, there is an emerging concept that reactive oxygen species (ROS such as )

superoxide anion O2-hydroxyl radical (OH-), lipid radical (LOO-), peroxy radicals (XOO-) and singlet oxygen (O-).

ROS are products of mitochondrial respiration (energy production).

Free radicals

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Dietary sources of ROS• High fat diet and deep fries• High sucrose (or refined carbohydrates )diet• Protein + sugar in high temperature (glycation)• Low fruit and veg. diet• Low vitamin and mineral diet (antioxidant).

Life style: stress, pollution, smoking and low activity.

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Golden rule

• More free radicals = chronic diseases = faster aging.

• Less free radicals = healthier body.

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How to slow down generation of Free radicals?

• Homework.

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Comparison

A B

Distance: 200, 000 kmFuel consumption: 1000,000 liter

Distance: 10,000 kmFuel consumption: 50,000 liter

Waste?Maintenance?Type of fuel?

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The challenges for nutrition in the twenty-first century

1. Application of new scientific knowledge in nutrition.

2. Improved scientific knowledge on diet–disease relationships.

3. Exponential increase of health-care costs.4. Increase in life expectancy.5. Consumer awareness of nutrition and health

relationships.6. Progress in food technology.

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Functional foodsHistory

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• The project also proposed for the first time the new concept of “functional food” and defined food functions as primary (nutritional), secondary (sensory) and tertiary (physiological). Food with physiological functions was of particular interest, because such food would be useful for improving the health of the general public

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Definition • no simple, universally accepted definition of functional

food exists. Examples• food and drink products derived from naturally occurring

substances consumed as part of the daily diet and possessing particular physiological benefits when ingested.

• food derived from naturally occurring substances that can and should be consumed as part of the daily diet and that serve to regulate or otherwise affect a particular body process when ingested.

• food similar in appearance to conventional food, which is consumed as part of a usual diet and has demonstrated physiological benefit and/or reduces the risk of chronic disease beyond basic nutritional functions.

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The main aspects of this working definition are:

• the food nature of functional food that is not a pill, a capsule or any form of dietary supplement;

• the demonstration of the effects to the satisfaction of the scientific community;

• the beneficial effects on body functions, beyond adequate nutritional effects, that are relevant to improved state of health and well-being and/or reduction of risk (not prevention) of disease;

• the consumption as part of a normal food pattern.

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F F Science

• By reference to the new concepts in nutrition outlined above, it is the role of functional food science to stimulate research and development of functional foods

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Claim= promise of improvement

“Disease reduction claims” meaning:

consumers have difficulties to differentiate between the terms ‘disease risk reduction’ and ‘prevention of diseases’.

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How to write a claim

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EFFECT OF FOOD PROCESSING ON FUNCTIONALITY OF FOODS

In foods containing vastly different phytochemicals, the physiological activity due to food processing may be a result of more than one mechanism. Consequently, there may be a decrease, increase, or a slight change in the content and functionality of phytochemicals.

No/slight effect: carotenoids comprising of b-carotene and lycopene are generally stable to heat treatments encountered in blanching, cooking, and pasteurization/sterilization. Interactions between polyphenols and ascorbic acid may slow the degradation of the latter during storage.

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Decrease in content and activity of phytochemicals: a classic example is that of the “technological indicator,” ascorbic acid, which is by far the most sensitive nutrient, and can be damaged during most treatments. Chemical and/or enzymatic oxidations are reported to decrease the antioxidant efficacy of polyphenolics, while leaching into the cooking water is mainly responsible for loss of folates.

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Heat processing of Brassica vegetables of the Cruciferae family greatly reduces their functionality .

Manufacture of black tea causes a higher degree of enzymatic aerobic oxidation of flavonoids, resulting in lower antioxidant activity. Some processing operations such as peeling and juice clarification can remove the polyphenolics .

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Increase in content and activity of phytochemicals:

partially oxidized polyphenolics that result during food processing, have been recently shown to exhibit higher antioxidant activity than the corresponding non-oxidized forms, due to increased ability to donate a hydrogen atom

A moderate increase in carotenoid bioavailability andenhanced phytochemical nutrient function in cereal processing

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Examples of functional ingredients

Vitamin antioxidant & mineral premixes; tomato powder, garlic powder, onion powder, spice mixes; amino acids, chitosan; Omega-3-fatty acids (fish and flax seed); whey protein powder; Guarana extract, G. biloba extract, ginseng extract, rosemary probiotics; natural antioxidants (from tea); “shield” liquid antioxidants; vegetable peptones;

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essential fatty acids concentrates; performance proteins; natural fruit based flowering compounds; natural colours; total extracts of medicinal plants “antioxidants” soy ingredient, soy proteins, soy protein hydrolysate; soya protein isolate & concentrate; super critical extracts of spices; and herbs; glutamine peptides; lactoferrin, milk calcium; lycopene, garcinia, raw herbs; whey protein concentrate; wheat fiber, b-carotene; A. vera gel powder.

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Risk factor or state Design a Functional Food

CVD

osteoporosis

diabetes

Irritable bowl syndrome (IBD)

Pregnant woman

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OXIDATIVE STRESS AND ROS

• Oxidative stress = rusting of tissues.• Oxidative stress is imposed on the body ’ s

cells when the level of ROS outweighs the reducing capacity of antioxidant and antioxidative stress mechanisms

ROS

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Sources of ROS

• Endogenous sources of ROStissue injuryvia auto - oxidation reactions in the presence

of transition metal ions. Fe 2 + or Cu +

during cytochrome P450 cycling.at inflammatory sites by activated and

phagocytes.

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• Exogenous sources of ROSExposure to ultraviolet (UV) radiation.Overexercise.Extrinsic xenobiotics found in tobacco smoke. Heavy metals.Organic pesticides. Lipid hydroperoxides in particular are potentially

toxic products of peroxidized polyunsaturated fatty acids (PUFAs) derived from dietary fats.

Compounds present in foods such as transition metal ions, heme from meats, isoprostanes, additives, lipids,

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DEFENSE SYSTEMS

Glutathione ( GSH ):• tripeptide of γ – glutamylcysteinylglycine.• directly scavenge free radicals or act as a

substrate.• GSH present in foods and secreted in the bile

can contribute to GSH concentrations in the intestinal lumen.

Endogenous antioxidants and antioxidative defenses

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Antioxidative stress enzymes:• glutathione peroxidase (GPx).• glutathione S -transferase ( GST ).• Catalase Additional antioxidants:• uric acid.• bilirubin - bound albumin, and albumin itself.• Histidine - containing peptides such as carnosine.• Melatonin.• Amino acids, peptides, and even proteins.• Se, Zn, Cu, Mn and riboflavin can all have co-factor

functions for one of the above enzymes.43

Phytochemicals with antioxidant activities

• Polyphenols:5000 polyphenols and over 2000 flavonoids

having been identified.

Phenolic acids, Flavonoids, Lignans

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• Amidesstrong antioxidants: capsaicinoids in chili

peppers.• CarotenoidsLycopene, β – carotene, xanthophylls such as

zeaxanthin.

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Mechanism of action

(1) direct radical scavenging; (2) downregulation of radical production; (3) elimination of radical precursors; (4) metal chelation; (5) Inhibition of xanthine oxidase; (6) elevation of endogenous antioxidants.

Curcumin and flavonoids have been shown to upregulate intracellular GSH synthesis and increase antioxidant enzyme activities

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METABOLISM AND BIOAVAILABILITY OF FLAVONOIDS

• The extent of absorption of dietary polyphenols in the small intestine is relatively small.

• Bacterial enzymes may catalyze several reactions.

• Anthocyanins were found in the cerebellum, cortex, hippocampus. = important for learning and memory.

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Antioxidant and C D

• CVDAntioxidant prevent LL oxidation.• Cancer Block activation to carcinogens.DNA repair.Inhibit the formation and growth of tumors.

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Dietary Fiber

• Dietary fiber (DF) has been consumed for centuries and most food labels in the supermarket now list dietary fiber.

• Even though fiber is not considered a nutrient, health professionals and nutritionists agree that fiber is required in sufficient amounts for the proper functioning of the gastrointestinal tract.

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Definition

• DF is the edible parts of plants or analogous carbohydrates that are resistant to digestion and absorption in the human small intestine with complete or partial fermentation in the large intestine.

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Why ?• DF consumption has established the basis for

associating high-fiber diets in epidemiological studies with reduced risk of most of the major dietary problems in the U.S.A.; namely, obesity, coronary disease, diabetes, gastrointestinal disorders, including constipation, inflammatory bowel diseases.

Chronic diseases54

Classification Of Dietary Fiber

• dietary fiber has been to differentiate dietary components on their solubility in a buffer at a defined pH, and/or their fermentability in an in vitro system using an aqueous enzyme solution representative of human alimentary enzymes.

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• Soluble fiber dissolves in water• This includes gums, mucilages, pectin and some

hemicelluloses.

• found in all types of peas and beans like lentils, split peas, pinto beans, black beans, kidney beans, garbanzo beans, and lima beans, as well as oats, barley, and some fruits and vegetables like apples, oranges, and carrots.

Solubility

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Benefits

• For people with diabetes, eating foods that contain soluble fiber can help control or lower the level of sugar in their blood and decrease insulin needs

• It may also help lower blood cholesterol levels, especially LDL-cholesterol or the “bad” cholesterol.

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• Insoluble fiber does not dissolve in water.• Whole grains, wheat and corn fiber, and many

vegetables like cauliflower, green beans, and whole potatoes are good sources of insoluble fiber.

• aids digestion by trapping water in the colon.• helps prevent two kinds of intestinal diseases,

diverticulosis and hemorrhoids.

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Fermentability

• Fibers that are well fermented include pectin, guar gum, acacia (gum arabic), inulin, polydextrose, and oligosaccharides.

• Generally, well fermented fibers are soluble in water, while partially or poorly fermented fibers are insoluble.

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Physiological Effects of D fiber

• major physiological effects of dietary fiber originate from the interactions with colonic content throughout its fermentation.

• It influences several metabolic processes, including the absorption of nutrients, carbohydrate and fat metabolism, and cholesterol metabolism.

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• influences the colonic structure and barrier function, and as the large intestine encompasses a significant body of the human immune system.

• Some form gels (pectins), while others have a high water holding capacity (WHC).

• its ability to adsorb or bind bile acids; and its fermentability by microorganisms in the gut.

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Colonic Fermentation And Its Consequences

• The large intestine is the most heavily colonized region of the digestive tract, with up to 1011 -1012 anaerobic bacteria /gram.

• end products produced from the fermentation, including gases (methane, hydrogen, carbon dioxide), short chain fatty acids (SCFA).

• Increases in microbial mass from fiber fermentation contribute directly to stool bulk

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• Gas production from colonic fermentation can also have some influence on stool bulk.

• Poorly fermented cellulose produces very little acid during its fermentation, most of which is only acetic acid; by contrast, in the case of more fermentable fibers, large quantities of SCFA are formed.

• The metabolic end products of fermentation including the gases, SCFA, and increased microbiota, play a pivotal role in the physiological effects of fiber and implications for local effects in the colon and systemic effects

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PHYSIOLOGICAL FUNCTIONS OF DIETARY FIBER

• Dietary Fiber And CancerColon cancer is one of the leading causes of

cancer morbidity and mortality among both men and women in the Western countries, including the U.S.A.

• Dietary Fiber And Carbohydrate MetabolismAn association between insufficient dietary fiber

intake and increased risk of diabetes has been postulated since 1970s.

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• Dietary Fiber, Lipid Metabolism, And Cardiovascular Disease

bind bile acids increasing their excretion and decrease cholesterol in the liver.

SCFA are absorbed from the colon to the liver.• Dietary Fiber, Mineral Bioavailability And

Bone Health.certain highly fermentable fibers have resulted

in improved metabolic absorption of certain minerals, such as calcium, magnesium, and iron,

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• Dietary Fiber, Role In Gut Barrier Function And Gastrointestinal Disorders.

SCFA stimulating repair in a damaged colon.barrier to prevent foreign materials from dietary

or microbial origin from crossing into the internal body cavity. Prevent Intestinal permeability or “leaky gut syndrome’.

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Probiotics• Intestinal tract is home to one hundred trillion

(1014) microorganisms.• called the intestinal microflora.• over 400 different species of microbes.• The 400 species of microbes living in your

body are fighting for space. They want to live, thrive and reproduce in your intestinal tract, an environment that offers the ideal temperature, humidity and food sources.

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• Depending on the type of bacteria, there is a different effect on the body; bacteria can have healthy, e.g.,

• immune-boosting benefits or cause harm to the body.

A careful balance is necessary for health.

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• Bad microbes live in your intestines and normally do not cause any disease-like symptoms.

• Bad microbes flourish in an alkaline environment.

• Opportunistic and neutral = the majority.• Good microbes found in the body, called

probiotics.• Probiotics have a positive impact on the

body’s health. They prefer a more acidic intestinal environment. Many of the probiotics are called lactic acid bacteria. 71

They define the term probiotic as:live microorganisms which when administered in adequate amounts confer a health benefit on the host.

How do they work?What are these health benefits?How can we get them?What species can provide them?What’s the relationship with Chronic diseases?How can we maintain them?

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Some history • Pasture 1880,• Eli Metchnikoff 1908,• Tisser 1900,• W W I Nissil• Southeast Asia, Boulardi. Cholera.• 1950, group of scientists, found out that mice

that were given oral antibiotics, which kill all bacteria, including probiotics, were more susceptible to infection.

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• Yakult Company of Japan in the 1930s. Yakult Company introduced a fermented milk product that contained a probiotic culture.

• The term probiotic was not actually coined until the 1960s.

• In 1978, Dr. Tomotari Mitsuoka, illustrated how the composition of intestinal flora changes during a lifetime.

Probiotics decrease with aging.

WHY?

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How Do Probiotics Work?

• The intestinal microflora has the metabolic activity potential equal to that of the liver, the most active organ in the body!

• The exact mechanisms of action by which probiotics elicit their beneficial effects are not fully understood.

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Suggested mechanisms

• Probiotics Compete for Receptor Sites:

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• Change secretion to mask receptors:

mucus

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• Probiotics Affect the Immune System:Gastrointestinal tract is equipped with effective

immune system, the most number of lymphoid is around the gut.

Immune system is the key element of what to enter your body or not to.

By producing antibodies these are messengers for all tissues connected with immune system.

• Probiotics supplementation is useful in a wide variety of immune-based ailments including allergies, asthma, eczema and irritable bowel disease. 78

• probiotics help balance good and bad messengers of the immune system by keeping the system in check.

• The result is healthy immune reactions and a healthier you. A careful balance of inflammation is required in the intestinal tract.

• Too much of an immune reaction can result in inflammation and damage to the intestines reducing their ability to digest and absorb nutrients = I B D.

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• Too little immune reaction allows pathogens to grow in the intestines, causing infectious diarrhea, which can develop into a chronic illness such as allergies.

All in all, it appears that probiotics:• reduce allergic reactions• improve overall immunity• promote proper immune reactions against

pathogens.

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• Probiotics Consume Available NutrientsThere are lots of nutrients available in the

digestive tract that support the needs of lactic acid bacteria to grow. By consuming a large portion of the available nutrients suitable for microbes, lactic acid bacteria restrains the growth of bad microbes.

• Probiotics Create an Acidic EnvironmentMany bad microbes do not like a low pH.

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• Probiotics Produce Beneficial EnzymesThe enzyme activity of probiotics has been

found to help fight infectious disease, lactose intolerance, immune system deficiencies, and urogenital and vaginal diseases.

• Probiotics Produce Antimicrobial EffectsMany of the probiotic strains of bacteria are

able to produce substances that kill bacteria, called bacteriocins

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• Probiotics Support Gut BarrierLactobacilli and Bifidobacteria produce fats that

encourage the growth of cells that line the intestinal tract. These fats are called short chain fatty acids. These fats also have nutritional effects on the intestinal cells, keeping them well nourished and healthy.

= Gut integrity.

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• Probiotics Encourage Healthy MicrofloraIn clinical trials, the use of combinations of

probiotic species has been found to offer greater health benefits than any one of the probiotic species alone.

Example;Lactobacillus reuteri produces protein to

enhance the growth of other lactobacilli.

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Manufacture of ProbioticBacteria

• Lactic acid bacteria (LAB) have been used for many years as natural biopreservatives in fermented foods.

• Dried concentrated probiotic cultures are the most convenient form for incorporation into functional foods, given the ease of storage, handling and transport, especially for shelf-stable functional products.

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Probiotics are the main bioactive component of these fermented FF and numerous economic indicators show that probiotic-enriched products are still on the forefront of innovation in the FF sector:• The probiotic yogurt market in Latin America grew

32% annually from 2005 to 2007• In the overall USA FF market, in 2004, fresh dairy

products grew by 9–10% compared to 2% for cheese.• The European food and beverage probiotics is

expected to rise from its 2006 position of 62 million $ to 163 million $ by 2013

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Selection of Strains

• the microbes should have GRAS (Generally Regarded As Safe) status, have a long history of safe use in foods, be non-pathogenic

• acid and bile tolerant• should be viable (debatable).• the bacteria should tolerate different

technological stresses, such as acid, osmotic, cold, heat and drying stress.

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Selecting the appropriate strain for a particular food can be divided in four categories:

• Performance in the gastrointestinal tract (GIT)• Industrial production.• Safety of the microorganisms.• Health benefit.

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Question:

• Who do you think the most group of people in the community need functional foods, and Why?

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• Colorectal cancer (CRC) is the fourth most frequent cause of cancer related mortality in the world.

• Approximately 944,000 new cases were diagnosed globally in 2000 and this accounts for 9.2% of all new cancer cases.

• the developed world suffering the highest rates and India one of the lowest

Potential Protective Effectsof Probiotics Against Colorectal Cancer

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• Evidence suggests that diet plays an important role in the aetiology of colorectal cancer.

• associations between overweight/ obesity (waist circumference), processed meat, alcohol and increased risk of colorectal cancer.

• Fiber, garlic, milk and calcium are associated with decreased risk.

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Colon Carcinogenesis

• involves inactivation of various tumor suppressing genes.

• activation of mutations.• loss of function in DNA repair genes

Metabolic activity of microflora.

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Role of the Gut Flora in Cancer

• Once the microbiota is established, little qualitative variation in the composition occurs over time, although there is extensive evidence that the metabolic activity of the microbiota can be modulated by diet.

• Evidence from a wide range of sources supports the view that colonic microbiota is involved in the aetiology of cancer.

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• The main pieces of evidence are:1.Human feces have been shown to be

mutagenic and exert tumor promoting activity in vitro and genotoxic substances of bacterial origin have been isolated.

2. Intestinal bacteria can produce, from dietary components, substances with genotoxic, carcinogenic and tumor-promoting activity.

3. Gut bacteria can activate procarcinogens to DNA reactive agents.

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4. Germ-free rats treated with the carcinogen 1,2-dimethylhydrazine have a lower incidence of colon tumors than similarly treated rats having a normal microbiota.

5. Germ-free rats fed human diets exhibit lower levels of DNA defect in tissues than conventional rats.

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Evidence that probioticscan influence carcinogenesis is derived from a variety of sources:1. Effects on bacterial enzyme activities.2. Antigenotoxic effects in vitro and in vivo.3. Effects on pre-cancerous lesions in laboratory

animals.4. Effects on tumor incidence in laboratory

animals.5. Epidemiological and experimental studies in

humans.96

Examples:• metabolism of the primary bile acids to

secondary acids, which are thought to possess tumor-promoting activity.

• nitrite can be converted to N-nitroso compounds (mutagenic) by bacteria under neutral pH.

• In a conventional rat study, supplementation of a high meat diet (72% beef) with L. acidophilus (109–1010 organisms/day) significantly decreased by 40–50% the activity of fecal b-glucuronidase and nitroreductase

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• consuming milk supplemented with 109 viable lactobacilli per day decreased activity of feacal enzymes.

• LAB was able to bind the mutagens in vitro.• Production of SCFA, Acetate is the major SCFA

found in human feces. In the host, it may be absorbed and utilized by peripheral tissues

SCFA, in particular butyrate, are potential anti-carcinogenic.

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• Apoptosis: or programmed cell death is one of the primary mechanisms by which multi-cellular organisms control normal development. In cancer it is out of control.

Probiotics are able to balance apoptosis.

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First Exam

• 7-10-2013

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Prebiotics • Coined by G. Gibson, “non-viable food

component that beneficially affect the host by selectively stimulating the growth and/or activities of one or a limited number of bacteria in the colon,”

• Prebiotics allow the selective growth of certain indigenous gut bacteria.

• such as bifidobacteria and lactobacilli which are already resident in the human colon

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To be an effective prebiotic a colonic food must:

• neither be hydrolysed nor absorbed in the upper part of the gastrointestinal tract.

• have a selective fermentation such that the composition of the large intestinal microbiota is altered towards a healthier composition.

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Commercially available prebiotics

• fructose-containing oligosaccharides (FOSs).these prebiotics are the European market

leaders.• Bifidobacteria are able to breakdown and

utilise fructo-oligosaccharides due to their possession of the ß- fructofuranosidase enzyme.

• FOSs have proven prebiotic effects in human trials

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• Galacto-oligosaccharides (GOSs) are another class of prebiotics that are manufactured and marketed in Europe as well as Japan.

• They have found application in infant formula foods as

• they are naturally present (low quantity) in human milk.

• Gluco-oligosaccharides can also act as prebiotics. or Isomalto-oligosaccharides (IMOs). Slowly metabolized and pass to colon.

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• Xylo-oligosaccharides (XOSs) are also used as prebiotics in Japan

• XOS are much more acid stable than other prebiotics. For this reason, they have found application in soft drinks which tend to be acidic.

• Lactulose.

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• Dietary fibres (e.g. from wheat, maize, rice, soya) have always been considered to have a beneficial effect on gut function and colonic bacteria, but this is a generalised stimulatory effect and such polysaccharides are not selectively fermented in the colon.

Are Dietary Fibres prebiotics?

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Mechanisms of Prebiotic Impact on Health

• Local and Physiological Effects of PrebioticsMucosal Structure

1) increase in numbers of epithelial cells, and the intensities of their secretory functions.

2) enlarged the available area of nutrient absorption

possibly SCFA are responsible for these adaptive changes.

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• Intestinal Mucus

Made of mucin produced by goblet cells lining the gut. Act as barrier.

Mucus is a source of nitrogen and carbon for bacteria; its continuous production by the host makes the gut good environment for microorganisms,

1) Administration of dietary prebiotics appears to thicken the mucus layer and increase its secretion by goblet cells

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• Mineral Bioavailability

there is a strong inverse relationship between the amount of phytic acid in the diet and iron Ca, and Zn absorption.

1) prebiotics are known to have stimulatory effects on iron absorption in the large bowel.

2) Addition of FOS to the diet restores zinc absorption by enhancing zinc bioavailability

3) prebiotic consumption is associated with enhanced breakdown of phytic acid (60%), low pH decrease its solubility

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Undigested Food

(prebiotic)

pHMineral

Solubility

Colonic environment

Phytic acid

Ca

Zn

Fe

Probiotic bacteria

SCFA

Phytase enzyme

Zn FeCa

hydrolysisfermentation

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• Modulation of the Gut Microbiota

In chronic diseases and Gastrointestinal tract diseases it was found that decreased levels of bifidobacteria and lactobacilli are associated with the problem.

1) Prebiotic can increase these levels and prevent from C D.

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• Immune System

prebiotics, may be particularly useful in inflammatory conditions, or in children and the elderly.

FOS and lactulose to the diet has been shown to increase :

1) mucosal immunoglobulin production. 2) lymph nodes number.3) altered pro-inflammatory compounds in the spleen and intestinal mucosa.

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• Lipid Metabolism

Human studies have been small in scope, focused on the relationship between the intake of prebiotics and serum lipid levels. The results have been inconsistent, and any mechanisms of action unclear.Animal studies showed lowering effect of prebiotics on LDL and cholesterol (especially when fed high fat meal)

May be due to interference with hepatic lipogenesis.

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General Mechanism

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Prebiotics Applications1. Infants• Oligosaccharides are prebiotic factors in

human milk, causing increased levels of bifidobacteria in breast-fed babies compared to bottle-fed infants.

• Prebiotics have been used in infant formulas in Japan over the last 2 decades, and in Europe for the last 5 years.

• addition of 0.8 g/dl of a mixture of 10% short chain FOS and 90% long chain infant formulas was safe to add to infant formula.

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• Atopic Disease (allergy).• Allergic disease in infants is based on

imbalanced response to food allergen and lower numbers of bifidobacteria are found in allergic infant feces.

• By increasing the number of bifidobacteria prebiotics rebalance the immune response.

• Prebiotic feeding studies in allergic infants have demonstrated significant reductions in the incidence of atopic dermatitis, and this was associated with increased numbers of fecal bifidobacteria.

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• Enterocolitis• In premature infants, bifidobacterial

colonization is delayed in favor of high levels of enterobacteria and clostridia= enterocolitis.

• Breast-feeding has always been thought to protect against enterocolitis.

• No human studies using prebiotics alone.

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• Infection Prevention• Studies in children aimed at prevention of

infection have also had mixed results.• The addition of 1.1 g of oligofructose daily to

cereal of 123 infants (4–24 months) was associated with reduced episodes of fever and medical visits. The control group had more sick days, and a higher intake of antibiotics.

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• 134 infants fed prebiotics (8 g/l GOS/FOS) for the first 6 months of life, principally looking at allergic disease, the subjects were followed up until they were 2 years of age.

• fewer episodes of physician diagnosed infections , fewer episodes of fever and fewer antibiotic prescriptions.

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2. Gastrointestinal Effects• Irritable bowel syndrome (IBS) has been linked

to intestinal bacteria in a number of different trials.

• IBS is a difficult disease to investigate, because the symptoms are highly subjective and difficult to quantify.

• Gas production discomfort and flatulence are some of the symptoms associated with IBS.

• many patients have visceral hypersensitivity, so prebiotic fermentation and gas production may exacerbate their symptoms, and have adverse affects on health and wellbeing. 120

• Constipation• Prebiotics may have Laxative effects. May be

due to gas production and increased microbial mass.

• There is a good relation between intestinal motility and bacterial composition.

• With the exception of lactulose, the prebiotics studied so far in human trials have been shown to have little effect on managing constipation, and to have only mildly laxative properties.

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• Diarrhea & Antibiotic-Associated Diarrhea.• traveler’s diarrhea (E. coli) , frequency of

diarrhea in the prebiotic group (11.2%), compared to the placebos (19.5%).

• Clostridium difficile infections are antibiotic-associated diarrhea (AAD).

• Diarrhea associated with Clostridium difficile is a leading cause of hospital outbreaks of diarrhea and it considerably increases mortality and healthcare costs.

• Prebiotics reduce episodes of AAD and C. difficile diarrhea relapse.

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3. The Elderly• As people get older they often have a greater

susceptibility to diseases and suffer from an increase in gastrointestinal infections, malnutrition, constipation and diarrhea.

• decrease in immune function and a reduction in numbers of beneficial bacteria such as bifidobacteria, along with an increase in potentially harmful microrganisms.

• few studies on the use of prebiotics in the elderly.

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4. Other Areas.• Diabetes• Because prebiotics are non-digestible low

energy bulking ingredients this makes them beneficial they in diabetic control.

• The proposed mechanisms of action in diabetic disease involve SCFA. Since High concentrations of free fatty acids (mainly from food) in plasma lower the use of glucose in tissues, and induce insulin resistance.

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• Rheumatoid Arthritis.• In animal studies prebiotics showed ability to

decrease pro-inflammatory compounds by modulating the gut microbiota.

• Obesity• Prebiotics are excellent potential to act as

substitutes for sucrose, and to be used as sweeteners.

• GOS are stable at high temperatures and low metabolic value at 1.73 kcal/g, while FOS are similar at 1.5 kcal/g.

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• they promoted satiety, and reduced food intake.

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Resistant Starches• Resistant starches are defined as the sum of

starch and products of starch degradation not absorbed in the small intestine of healthy individuals.

• There are four main groups of resistant starches: RS1- RS4.

• RS1 is physically inaccessible starch (i.e., starch in whole grains), RS2 is granular starch i.e., starch in green bananas), RS3 is retrograded starch (i.e., starch in cooked and cooled potatoes) and RS4 is a chemically-modified starch (i.e., an esterified starch). 127

• RS has a calorific value of 1.70 kcal/g.• The glycemic response for RS is approximately

10% that of a maltodextrin control.• Type 3 RS was shown to be well tolerated up

to doses as high as 45 g/d.

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Applications• Applications for RS include puffed or sheeted

snacks, chips, extruded breakfast cereals, pasta, muffins, cookies and biscuits, crackers, frozen dough, breads.

• it can also be used in low calorie products reducing both calories and carbohydrates when replacing flour or other cereal-based ingredients.

• Due to its low water holding property, it also does not affect height and spread management of biscuits, cookies or other baked goods.

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• RS enhances crispiness of cookies and crackers.

• In fried snacks, fat uptake may be reduced by up to 25% when RS is used, helping to meet ‘‘high/rich in fiber’’ claims.

• RS3 thermal stable as high as 150⁰ C, it will retain more fiber content and structure than other resistant starches, which start to breakdown below 120⁰ C.

• RS act as prebiotics in the gut.• Sugar derived from RS can be used as

sweeteners. 130

Workshop design

Functional foods in Palestine, What do we need to know?

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Garlic and Onion as Functional Foods

• Historically garlic and onion were used to preserve food from microbial spoilage.

• Garlic has been eaten more than 4000 years and onion was cultivated in middle east before 5000 years.

• They were used for their medicinal properties.• Garlic on the top of vegetable-pyramid

representing potency in cancer prevention (NIC).

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GENERAL COMPOSITION AND SULFURCOMPOUNDS OF GARLIC AND ONION

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• The general composition is, of course, important to the nourishment of both garlic or onion eaters, however, in respect to the food function, the extraordinary high content of sulfur compounds in these vegetables should be much more important.

• These compounds are present as a group of sulfur-containing amino acids.

• When injured or damaged by slicing, the sulfur-containing amino acids in these plants are transformed immediately into volatile organosulfur compounds.

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• These compounds are called Alliins.• Alliin is degraded by alliinase into pyruvic acid

and ammonia.• Alliinase is heat labile, and irreversibly

inactivated at pH 3.8 or lower.• Oxidation of Alliins produces Allicin which has

bactericidal and fungicidal effect.= in water it is active up to 40 days.= at -70⁰C up to 2 years.

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• Organoselenium Compounds in Garlic and Onion.

• Allium plants, especially garlic and onion, is their strong potential to uptake inorganic selenium, either selenate or selenite, from the soil or water culture medium, and synthesize organoselenium compounds.

• Se-containing peptides, has been determined, and from this peptide a potent agent for cancer prevention was derived.

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PHYSIOLOGICAL AND NUTRITIONAL FUNCTIONS OF GARLIC AND ONION, AND THEIR HEALTH BENEFITS

• Garlic and onion use sulfur compounds to protect themselves, Even in our bodies, sulfur-containing compounds play a defensive mechanism.

• Onion has a lesser amount of sulfur compounds as compared with garlic. However, because people consume onion much more than garlic, the amount of sulfur compounds taken from onion per person may be comparable to or more than that from garlic.

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• Antibiotic Effect.• growth inhibition by an aqueous garlic extract.

Which was diluted 100 times with water (about 10 ng/ml allicin) showed a clear inhibition zone, and some fungus did not grow inside of the zone for up to 7 days.

• Alkyl thiosulfinates are recognized as the most effective compounds exhibiting antimicrobial activity.

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• Antithrombotic Effect.• Suppression of platelet aggregation is the

most beneficial effect of garlic intake.• vascular dilation have been observed primarily

with garlic oil in human and animal studies.

• Thus, garlic may prevent thrombus formation through many mechanisms involving antithrombotic, vasodilative effects.

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• Lipid-Lowering Effect.• several garlic compounds have been reported

to be effective.• The lipid-lowering effects appear to be due to

their degradation products, those that may be produced from the compounds soon after the absorption from the intestine.

• And from the reduced gene expression may be an important factor in the lipid-lowering effects of garlic.

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• Hypoglycemic Effects.• It has been proposed that garlic compounds

stimulate insulin production and prolong insulin turnover.

• Especially, sulfur compounds from garlic were considered to protect insulin from its inactivation.

• alliin (200 mg/kg) is known to reduce the plasma glucose level in diabetics.

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• ANTICANCER EFFECTS OF GARLIC AND ONION• A number of epidemiological and

experimental studies indicated that garlic and onion can be considered as important functional foods for cancer prevention.

1.study in northeast China found that the consumption of onion was inversely related to the risk of developing brain cancer.

2.Similar studies reported that garlic intake significantly reduced the risk of prostate and breast cancers, and increased protective power against stomach and colorectal cancers. 143

3. Site-specific case-control studies on stomach and colorectal cancers suggest a protective effect of high intake of raw and/or cooked garlic.

4. The overall anticancer effects that have been reported for garlic and onion by some hundreds of researchers can be collected largely into three groups:

A. Antimutagenic and anticarcinogenic effects.B. Antiproliferative effects.C. Differentiation effects involving the apoptotic

effect.144

• Other Effects.• blood pressure-lowering.• Diuretic.• anti-inflammatory, immunomodulatory.• Enhancing effect on vitamin B1 absorption.• stimulate both noradrenaline secretion from

nervous systems and testosterone from testis.

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Garlic processing• Cutting, slicing, crushing.Allicin from damaged garlic turned to sulfides. Allicin may collected when slicing garlic in water,

but sulfides better collected in cooking oil.• Boiling and heatingIf an intact bulb is heated, alliin stays unchanged

inside the bulb. • if the heating is not quite sufficient to denature

the alliinase, a large amount of alliin is transformed into allicin and sulfides while cooking or eating the bulb.

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Heating the chopped garlic in cooking oils, allicin, sulfides as well as alliin must be present, in the oils or within the pieces. Hence, people prefer to cook garlic with cooking oils or fatty meats.

• Pickling The pickled clove in any medium loses alliinase

activity more or less, depending on the period of its preservation. It takes at least a month to penetrate a medium into the clove with a gradual decrease in alliinase activity.

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• Garlic Oil• Garlic Powder• Dehydrated Onion Pieces• Onion Powder• Onion Oil• Onion Salt• Pickled Onion

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Quiz

• Discuss briefly how probiotics and /or prebiotics may prevent from cancer?

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Green and Black Tea• Tea (Camellia sinensis) has been discovered

and utilized for its unique flavor and medicinal properties by man for a long time, which may be traced back to 5000–6000 years ago in China.

• Tea beverages are now the second most popular drinks and only next to water in terms of worldwide consumption.

• Scientific research on the chemical components and functionalities of tea is relatively recent. 151

• Through research, tea has been linked with health benefits including protection of oxidative DNA damage, lowering the atherosclerotic index and improving blood flow, liver function, and oral health.

• Nowadays, the utilization of tea has been extended not only to pharmaceutical products but also to toiletry, cosmetic, and food products.

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• Commercial tea leaf products can be classified into three major types: green tea, black tea, and oolong tea.

• Green tea is nonfermented processed tea, in which polyphenols in fresh tea leaves are less oxidized.

• Black tea and oolong tea are enzymatically fermented tea, with black tea being the most fermented and oolong tea partially fermented (or so called semifermented).

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Tea polyphenols • The functional properties of tea are believed to

be due to tea polyphenols. The principal tea polyphenols are tea catechins.

• Catechin has been accepted as a quality indicator of green tea products.

• There are some 8–30% of total catechins in dry green tea leaves.

• The estimated daily intake of tea catechins based on 3 cups (600 mL) of green tea (1– 4 g), which is brewed traditionally (1–5 min in boiling water), is in the range of 538–2594 mg of total catechins.

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• the antioxidative activity/free radical scavenging ability of tea catechin varies with the type of radical species, ionization state, pH, polarity, and enzyme in the designated studies.

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GREEN TEA ANTIOXIDANTS AND HEALTH BENEFITS

• Green Tea and Neurodegenerative Diseases• Catechins chelate metal ions such as

copper(II) and iron(III) to form inactive complexes and prevent the generation of potentially damaging free radicals.

• In the rat brain tissue, green tea and black tea extracts were shown to inhibit lipid peroxidation promoted by iron.

• As well decrease neurons death (Alzheimer's) 156

• Green Tea and Obesity• Polyphenols interact to alter the energy

balance.• the redox status or potential.• the activities of obesity-related cells.• Green Tea and Cardiovascular Disease.• cardiovascular diseases is multifactorial and

comprises processes, which appear to be affected by tea ingredients:

• endothelial dysfunction.• inflammation. And • thrombus formation

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• Green Tea and Cancer• inhibition of oxidative stress.• inhibition of carcinogen.• induction of apoptosis.• Inhibition of angiogenesis.Type of cancers: • Skin cancer: Studies have suggested that

green tea polyphenols may afford protection against inflammatory responses and the risk of skin cancer.

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• Lung Cancer: Ingestion of green tea (2% of diet) decreased the number of lung induced tumors in mice.

• consumption of green tea was associated with a reduced risk of lung cancer among nonsmoking women and the risks decreased with increasing consumption.

• Liver Cancer: In a study in China it was found that Green tea drinking decreased the risk for the development of liver cancer by 78% among alcohol drinkers and 43% among cigarette smokers.

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• Breast Cancer: green tea consumption was associated with a reduction in breast cancer risk.

• Prostrate Cancer: Green tea• inhibits the growth and progression of

prostate cancer in model mice.• ANTIBACTERIAL AND ANTIVIRAL ACTIVITY:• Antimicrobial activity against cariogenic and

periodontal bacteria has been reported.• Tea extracts inhibit enteric pathogens such as

Staphylococcus aureus, Salmonella typhi, Shigella, V. cholerae, Cam. jejuni, 160

• Tea polyphenols also inhibit bacteria responsible for tooth decay.

• black and green tea extracts can kill Helicobacter pylori associated with gastric, peptic, and duodenal ulcer diseases.

• but are not effective against Escherichia coli, Pseudomonas aeruginosa.

• Some results indicate that tea catechins are potentially antiviral and antiprotozoiac agents

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Polyphenols stability • The stability of tea catechins is dependent on

pH and temperature. In acidic systems (pH < 4), tea catechins are fairly stable.

• in systems of pH > 5, that is, near neutral or alkaline systems, they degrade rapidly.

• On the contrary, tea catechins become less stable when processing temperature increases, where thermal degradation, oxidation could occur.

• 82°C was reported as a turning point in thermal reactions of tea catechins 162

• Ascorbic acid showed a significantly protective effect on the stability of tea catechins.

Functional food containing Green tea.green tea beverage products.Sport beverages.cereal, confectionary, dairy, edible oil.ice cream and noodle products containing green

tea.• Green tea extracts have also been

incorporated in chocolates and chewing gums.

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Tea and ironCrit Rev Food Sci Nutr. 2000 Sep;40(5):371-98.Effect of tea and other dietary factors on iron absorption.Zijp IM, Korver O, Tijburg LB.Abstract• Iron deficiency is a major world health problem, that is, to a great extent,

caused by poor iron absorption from the diet. Several dietary factors can influence this absorption.

Absorption enhancing factors are ascorbic acid and meat, fish and poultry; inhibiting factors are plant components in vegetables, tea and coffee (e.g.,

polyphenols, phytates), and calcium.• For subjects at risk of iron deficiency, the following recommendations are

made. Increase heme-iron intake (this form of dietary iron present in meat fish and poultry is hardly influenced by other dietary factors with respect to its absorption); increase meal-time ascorbic acid intake; fortify foods with iron.

• Recommendations with respect to tea consumption (when in a critical group) include: consume tea between meals instead of during the meal; simultaneously consume ascorbic acid and/or meat, fish and poultry.

Display Settings:•AbstractSend to:

Crit Rev Food Sci Nutr. 2000 Sep;40(5):371-98.Effect of tea and other dietary factors on iron absorption.

Zijp IM, Korver O, Tijburg LB.

SourceUnilever Research Vlaardingen, The Netherlands.

AbstractIron deficiency is a major world health problem, that is, to a great extent, caused by poor iron absorption from the diet. Several dietary factors can influence this absorption. Absorption enhancing factors are ascorbic acid and meat, fish and poultry; inhibiting factors are plant components in vegetables, tea and coffee (e.g., polyphenols, phytates), and calcium. After identifying these factors their individual impact on iron absorption is described. Specific attention was paid to

the effects of tea on iron absorption. We propose a calculation model that predicts iron absorption from a meal. Using this model we calculated the iron absorption from daily menus with varying amounts of enhancers and inhibitors. From these calculations we conclude that the presence of sufficient amounts of iron absorption enhancers (ascorbic acid, meat, fish, poultry, as present in most industrialized countries) overcomes inhibition of iron absorption from even large amounts of tea. In individuals with low intakes of heme iron, low intakes of enhancing factors and/or high intakes of inhibitors, iron absorption may be an issue. Depletion of iron stores enhances iron absorption, but this effect is not

adequate to compensate for the inhibition of iron absorption in such an inadequate dietary situation. For subjects at risk of iron deficiency, the following recommendations are made. Increase heme-iron intake (this form of dietary iron present in meat fish and poultry is hardly influenced by other dietary factors with respect to its absorption); increase meal-time ascorbic acid intake; fortify foods with iron. Recommendations with respect to tea consumption (when in a critical group) include: consume tea between meals instead of during the meal; simultaneously consume ascorbic acid and/or meat, fish and poultry.

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Am J Clin Nutr. 2001 Mar;73(3):607-12.Green tea or rosemary extract added to foods reduces nonheme-iron

absorption.Samman S, Sandström B, Toft MB, Bukhave K, Jensen M, Sørensen SS, Hansen

M.AbstractBACKGROUND: • Phenolic compounds act as food antioxidants. One of the postulated

mechanisms of action is chelation of prooxidant metals, such as iron. Although the antioxidative effect is desirable, this mechanism may impair the utilization of dietary iron.

Results• The presence of the phenolic-rich extracts resulted in decreased nonheme-

iron absorption. Mean (+/-SD) iron absorption decreased from 12.1 +/- 4.5% to 8.9 +/- 5.2% (P < 0.01) in the presence of green tea extract and from 7.5 +/- 4.0% to 6.4 +/- 4.7% (P < 0.05) in the presence of rosemary extract.

CONCLUSION: • Phenolic-rich extracts used as antioxidants in foods reduce the utilization of

dietary iron. 165

• J Hum Nutr Diet. 2004 Feb;17(1):43-54.• Impact of tea drinking on iron status in the UK: a review.• Nelson M, Poulter J.AbstractBACKGROUND: • The aims of this review are (1) to evaluate the literature on the

likely impact of tea drinking on the iron status of different groups within the UK population

RESULTS: • There is clear evidence to show that tea drinking limits the

absorption of nonhaem iron.CONCLUSION: • From the available evidence there is no need to advise any

restriction on tea drinking in healthy people with no risk of iron deficiency. In groups at risk of iron deficiency the advice should be to drink tea between meals and to wait at least 1 h after eating before drinking tea. 166

What will happen to gut microflora if there is more iron in the gut?

• Good bacteria don’t require iron for growth (this is the case in infants).

• Enterobacteria require iron for growth.

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• Am J Clin Nutr. 2010, 92(6):1406-15.The effects of iron fortification on the gut microbiota in

African children: a randomized controlled trial in Cote d'Ivoire.

BACKGROUND: • Iron is essential for the growth and virulence of many

pathogenic enterobacteria, whereas beneficial barrier bacteria, such as lactobacilli, do not require iron. Thus, increasing colonic iron could select gut microbiota for humans that are unfavorable to the host.

OBJECTIVE: • The objective was to determine the effect of iron

fortification on gut microbiota and gut inflammation in African children.

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RESULTS: • At baseline, there were greater numbers of fecal

enterobacteria than of lactobacilli and bifidobacteria.• There was a significant increase in the number of

enterobacteria and a decrease in lactobacilli in the iron group after 6 mo.

CONCLUSIONS: • Anemic African children carry an unfavorable ratio of

fecal enterobacteria to bifidobacteria and lactobacilli, which is increased by iron fortification. Thus, iron fortification in this population produces a potentially more pathogenic gut microbiota profile, and this profile is associated with increased gut inflammation.

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Will the chelated iron by tea polyphenol affect gut microflora?

• If you find the answer you get 5 marks

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Sesame for FunctionalFoods

• Sesamum indicum L., is believed to have originated in the Savanna of central Africa spreading to Egypt, India, the Middle East, China.

• Medicinal value and anti aging (seeds and oil).• Despite such high values placed on sesame

seed and oil, there have been few scientific studies to elucidate their functions.

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• Regarding the worldwide per capita consumption of sesame seed, South Korea is highest, at 6–7 g/day and Japan follows with about 2–3 g/day.

• The growth period for sesame usually ranges from 3 to 4 months but flowering begins as early as 30−40 days after sowing.

• Blooming continues until maturity, and the seeds scatter suddenly from the capsule, as illustrated by the magic words, “Open, sesame!” As a result, harvesting of sesame cannot be done mechanically but requires extensive manual labor.

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SESAME SEED AS FOOD• It contains much oil (about 50%), which is very

stable against oxidative deterioration.• about 20% protein plus various minor

nutrients.• The good flavor generated by roasting sesame

seeds is also a highly desirable characteristic.• used as a topping for many baked foods such

as breads, biscuits, and crackers.• sesame paste is generally used. For example,

the paste is the base for much of the cooking (called tahina) and for cake (halva).

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COMPOSITION OF SESAME SEEDOIL• The average content of oil was 55% in white-

seed strains and that of black-seed strains was 47.8%.

• Fatty acids in the oil are mainly oleic (18:1 = 39.1%) and linoleic (18:2 = 40.0%) acids.

• sesame oil in which n−3 fatty acid content is low so it will be inferior to soybean and corn oils.

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• PROTEIN.• Sesame seed contains about 20% protein.• the amino acid composition of sesame seed

protein is slightly lower in lysine (31 mg/g protein), but higher in other amino acids, especially methionine (36 mg), cystine (25 mg), arginine (140 mg), and leucine (75 mg).

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• CARBOHYDRATE.• The carbohydrate content in sesame seed is

about 18–20 wt.%• The presence of small amounts of glucose and

fructose, and also an oligo sugars.• no starch is present. • Most carbohydrates seem to be present as

dietary fibers, and the content of the dietary fibers has been reported to be 10.8%.

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• VITAMINS AND MINERALS• sesame seed contains a significant amount of

the vitamin B group. Since the vitamin B group is contained only in the coat or hull of the seed, it is necessary to use sesame fl our or paste of whole sesame seed for utilization of the vitamin B group in sesame seed.

• vitamin E is very interesting in relation to the effectiveness of sesame seed as a health food.

• sesame seed appears to contain very little vitamin E activity.

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Functional composition

Lignan• sesame seed contains significant amounts of

lignans such as sesamin, sesamolin, sesaminol.• sesame lignans are being noted as the most

important and characteristic components of sesame seed in view of their various functional activities.

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• EFFECT OF SESAME SEED AND LIGNANS ON LIPID METABOLISM

1- CONTROLLING ACTION OF SESAME LIGNAN ON THE N−6/N−3 RATIO OF POLYUNSATURATED FATTY ACIDS

The n−3 series polyunsaturated fatty acids in the diets are assumed to be related to the onset of such diseases as arteriosclerosis, cancer and allergy diseases, and the ingestion ratio of fatty acids of the n−6 series to those of the n−3 series is considered to be significant.

it was found that sesame lignans have the ability to adjust the ratio of n−6/n−3 in the organism.

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2- EFFECTS OF SESAMIN ON FATTY ACID OXIDATION AND SYNTHESIS.

• the level of fatty acids in the liver was reduced by the intake of sesame lignans.

• the level of serum triglycerol Was reduced.• Dietary sesamin increased the hepatic activities of

fatty acid oxidation enzymes as well as the enzymes involved in β-oxidation of unsaturated fatty acids dose-dependently.

• Lower the lipogenic enzymes.

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• HYPOCHOLESTEROLEMIC ACTIVITY OF SESAME LIGNANS.

• sesamin is effective in preventing cholesterol accumulation in the liver.

• sesamin has the effect of lowering serum cholesterol in rats independent of the addition of cholesterol into the diets.

• Lignans increased the concentration of total HDL, and they also effectively decreased serum VLDL.

• The lowering effect of sesamin on cholesterol concentration may occur mainly through inhibition of the absorption of cholesterol from the intestine.

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ANTIHYPERTENSIVE ACTIVITY OF SESAMIN.• Results (mainly on rats) indicated that chronic

ingestion of vitamin E and sesamin have adjusted elevation in blood pressure, oxidative stress, and thrombotic tendency, suggesting that these treatments might be beneficial in the prevention of hypertension and stroke.

IMMUNOREGULATORY ACTIVITY.• effects on the plasma levels of

immunoglobulins.182

• PREVENTION OF CANCER.• In the growth of breast cancer of rats, a

significant suppressive effect was observed when fed a sesamin-containing diet (0.2%).

• The dietary lignans significantly decreased the incidence of colon cancer.

• Sesame oil decreased the side effect of drugs used by cancer patients.

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HYPOGLYCEMIC ACTION OF SESAME• May be due to delay in glucose absorption.PREVENTION OF ALZHEIMER’S DISEASES• Due to Anti oxidant activity. • ANTITHROMBOSIS ACTIVITY.• This activity was determined by the inhibitory

effect on human blood platelet aggregation.

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Fenugreek as functional food

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• Fenugreek (Trigonella foenum-graecum) is an annual herb that belongs to the family Leguminosae and has a long history of traditional use as a condiment and a medicinal herb.

• The seeds are assumed to possess nutritive and restorative properties and to stimulate digestive processes. It is supposed to be a tonic, and diuretic, chronic cough, external and internal swellings, and hair decay. The seeds are described in the Greek and Latin as possessing antidiabetic activity

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• In India, fenugreek seeds are used as a stimulant for lactation. They are known to be important constituents of the traditional food consumed during lactation.

• In Egypt, the seeds are used to supplement wheat and maize flour for bread-making .

• In some Arab countries, the seeds are used for the preparation of hot beverages after adding sugar . In Sudan, it is used in porridge and dessert and consumed mostly by lactating mothers .

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COMPOSITION OF SEEDS• The typical nutrient composition of fenugreek

seeds (g/100 g) is:• moisture 2.9 • protein 26.5 • fat 7.9 • saponins 4.9 • total dietary fiber 57.8 (consisting of gum

19.0, hemicellulose 23.6, cellulose 8.9, lignin 2.4, and ash 3.9).

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• Fenugreek seeds are reported to be rich in fl avonoids (100 mg/g).

• The fenugreek leaf is rich in vitamins A, D, B1, B2, B3, B6, B12, biotin, pantothenic acid, folic acid,and choline,

• and minerals such as iron, selenium, phosphorus, and potassium.

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THERAPEUTIC APPLICATIONS OF FENUGREEK

• HYPOGLYCEMIC ACTION.• Both the seeds and leaves are found to

possess antidiabetic properties.• Experiments on human (healthy and type 1

diabetes), rats, dogs, mice.• The improvement in clinical symptoms

followed alterations in biochemical parameters such as a reduction in the blood glucose level and urinary excretion of glucose.

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• improve insulin sensitivity , glucose metabolism, and lipid profile.

• type 2 diabetes received a daily dose of 1 g of extract of fenugreek seeds.= The mean fasting blood glucose levels were reduced.

• The addition of powdered fenugreek seeds (15 g) soaked in water significantly reduced the subsequent postprandial glucose levels.

• Plasma insulin also tended to be lower, although the reduction was not statistically significant. (non-insulin dependant)

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• Mechanisms hypoglycemic effects :• by stimulating glucose-dependent insulin

secretion from pancreatic β-cells.• by inhibiting the activities of α-amylase and

sucrase.

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• LIPID-LOWERING EFFECTS.• Supplementation of 100 g defatted fenugreek

powder per day for 3 weeks reduced TG and LDL-C levels from the baseline values. Slight decreases in high-density lipoprotein cholesterol (HDL-C) levels were also noted.

• TC levels decreased in five diabetic patients treated with fenugreek seed powder (25 g per day oral) for 21 days.

• Saponins present in the defatted part (4.8%) and cholesterol form insoluble complexes and retard cholesterol absorption in the intestine.

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• IMMUNOMODULATORY AND ANTI-INFLAMMATORY EFFECTS.

• An aqueous extract of fenugreek seeds showed immune stimulating effect on macrophages and showed a positive effect on specific and non-specific immune functions of the lymphoid organs such as the thymus, bone marrow, spleen, and liver.

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• ANTITUMOR EFFECTS.• Epidemiological evidence suggests that

dietary spices and fiber prevent colon carcinogenesis.

• Flavonoids and fiber can potentially act as anticarcinogenic agents by binding to free carcinogens and/or carcinogenic metabolites.

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• ANTIOXIDANT ACTIVITY.• A polyphenol-rich extract of fenugreek seeds

protected erythrocytes from peroxide-induced oxidative hemolysis.

• Dietary administration of fenugreek seeds resulted in an increased GSH (dose dependant).

• Germinated seeds have higher antioxidant activity than non germinated.

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• GASTROINTESTINAL FUNCTION.• diet containing 2% fenugreek seed improved

the intestinal function by enhancing the activities of terminal enzymes of digestive process.

• Seeds are supposed to stimulate appetite.• gastroprotective and antisecretory activities

of the seeds against ulcer.

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Functional Foods from Date Fruits• History • PHYSICO-CHEMICAL CHARACTERISTICS.• dates are a rich source of mainly

carbohydrates (fructose and glucose), but smaller quantities of vitamins, minerals, and other minor constituents are also present.

• the sucrose content increased rapidly as the date fruit matured and then decreased to a non detectable level at the tamer stage of maturity

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• The crude fiber content of date fruits at the Balah stage is substantially higher (6.2 to 13.2%) than that at the tamer stage (2.1 to 3.0%) of maturity.

• The total dietary fiber content (comprised of pectin, hemicellulose, cellulose, gums, mucilages, resistant starch, and lignin).

• Dates, at all stages of maturity, are low in fat (about 1%), but quite rich in minerals, certain B-complex vitamins, and polyphenolic compounds.

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• Among the minerals, dates are especially rich in potassium, but at the same time, are low in sodium, thus proving to be an excellent food for persons suffering from hypertension.

• good sources of iron, copper, sulfur, and• manganese; and fair sources of calcium,

chloride, and magnesium.

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• ANTIOXIDANT, ANTIMUTAGENIC, ANDIMMUNOSTIMULANT PROPERTIES

• Decrease free radicals• Enhance spleen function• Immuno-stimmulant for mothers giving birth.ANTIMICROBIAL PROPERTIES.• The Berhi date-fruit extract (20%, w/v) is capable

of inhibiting the growth of Bacillus subtilis, Staph aureus, S typhi, and Ps aeruginosa by about 80 to 99%.

• Spore germination of B. subtilis can be inhibited completely using various concentrations of date extract. 201

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Ideas

• energy bars and confectionery.• Bars made with tamer date pulp, sesame

seeds, almonds and oat flakes have been found to be quite acceptable to consumers.

• date bars prepared from date fruit, almonds, coconut, groundnuts, and pistachios can also be coated with chocolate, and stored for about 6 months at 25 ± 5°C.

• Tamaroggtt is another regional product that can be made from tamer date fruits and oggtt (a fermented dried milk).

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First exam analysis

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Olive and olive oil as functional foods

• The olive tree, Olea europea L., is the only species of the Oleacea with edible fruit.

• Cultivation began in the Mediterranean countries more than 6000 yr ago, was developed in Andalucia by Arabs, and then came to be introduced to the America continent.

• Among the 1500 olive cultivars catalogued in the world, only approximately 100 cultivars are classified as main producing varieties

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• The world production of table olives is estimated to surpass 1.5 million tons per year, with the Mediterranean countries being the main producers.

• There has been an increased demand for fermented green and black table olives in recent years in all regions of the world because their nutritional and functional foods proprieties.

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NUTRITIONAL COMPONENTS OF OLIVES

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• The olive fruit consists of a pulp and a stone representing 70 to 90% of the olive weight, and the pit another 10 to 30%.

• The pulp consists mainly of oil (10 to 25%) and water (60 to 75%). The oil fraction includes mainly triglycerides, diglycerides, monoglycerides, free fatty acids, sterol esters, terpenes alcohols, and phospholipids.

• Free sugars including mainly glucose, fructose and sucrose range from 3 to 4%, and they are very important for olive fermentation

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OLIVE OIL

• The best quality olive oil is termed Virgin oil or extra virgin olive oil (EVO).

• This is the oil that is first expressed under light pressure during processing and not further refined.

• it has less polyunsaturated fatty acids than other oils gives it a better shelf life.

• Furthermore, it has a mixture of tocopherols, including vitamin E, which can give a protective effect.

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• Typically, olive oil may oxidize easily and produce a strong flavor.

• All of the oil is pressed from the pulp and then collected.

• If the process occurs above 86 ⁰C, it is no longer considered “cold press,” which is one of the characteristics of extra virgin olive oil.

• The three basic grades of olive oils that consumers have access to are: (1) extra virgin, (2) virgin, and (3) olive oils.

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Functional properties of olive oilPrevent from CORONARY HEART DISEASE.• The general consensus appears to be that

mono- and polyunsaturated fatty acids are similar in terms of their cholesterollowering abilities.

• Several studies have shown that monounsaturated fatty acids decrease total blood cholesterol, LDL cholesterol, and triglycerides, with no changes in HDL cholesterol.

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• Although polyunsaturated fatty acids may lower blood lipids, they elevate the oxidative susceptibility of LDL, in contrast to fats that contain elevated saturated and monounsaturated fatty acids.

• There are a number of phenolic compounds in extra virgin oil .

• The simple phenolic compounds are hydroxytyrosol, tyrosol, and phenolic acids such as vanillic and caffeic acids.

• Many studies on olive oil are linked to studies on the Mediterranean diet where other dietary factors could play a role in the findings.

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OLIVE OIL AND INFLAMMATION• olive oil and its phenolic compounds are

mediators of inflammation.• Antioxidant activity against free radicals.HYPERTENSION• olive oil may lower blood pressure.• extra virgin olive oil, as compared to refined

olive oil, lowered systolic blood pressure in hypertensive patients.

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Prevention of CANCER.• BREAST CANCER.• consumption of a high oleic acid derived from

olive oil, typical of the Mediterranean diet is related with lower B C incidence.

• Consumption of olive oil has been shown to reduce mammary tumor incidence even when compared with safflower oil which contains similar amounts of oleic acid but higher levels of linoleic acid.

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• It has been hypothesized that an olive oil diet could reduce susceptibility of tissue structures to damage by free radicals, and thus the incidence of breast cancer.

PROSTATE CANCER.• Studies have suggested that diets high in olive

oil may afford protection against prostate cancer.

• It was also unclear whether the fatty acids or the antioxidants in olive oil were the responsible factor.

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OTHER CANCERS• cancer of the oral cavity and pharynx.• Colon cancer, as olive oil replaces fat.

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Functional Properties of Table Olives

• Table olives are a traditional fermented functional food, and one of the most important components of the Mediterranean diet.

• In general, about 5 to 10 table olives supply the daily intake of polyphenols.

• olives with changed color in brine had the highest concentration in polyphenols (approximately 1200 mg/kg), whereas oxidized olives had the lowest (approximately 200 mg/kg).

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• black olives contain higher concentrations of phenolic compounds, present higher antioxidant activity compared to green olive extract.

• With the aim of developing new functional foods, the table olive was used as a vehicle for incorporating probiotic bacterial species.

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Some other functional foods• Tomatoes• Tomatoes have been in the spotlight since the

mid - 1990s because of the presence of lycopene, a primary carotenoid, with strong antioxidant and health regulatory function.

• Consumption of products containing lycopene has been linked to a reduced risk of cancer especially cancers of the prostate, breast, digestive tract, cervix, bladder, and skin, and possibly the lung.

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• Consumption of tomato products 10 or more times per week had less than half the risk of developing advanced prostate cancer than the controls.

• Cruciferous vegetables• include broccoli, cabbage, caulifl ower, Brussels

sprouts, collard, kale, kohlrabi, turnip, mustards, horseradish, and watercress.

• reduce the risk of developing several kinds of cancer

• The cruciferous vegetables have high concentrations of glucosinolates which have been linked to the anticarcinogenic properties of cruciferous vegetables

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• Citrus fruits• There are many physiologically active

components in citrus fruits, among them citrus flavonoids and limonoids. appear to block and suppress carcinogens.

• Some of the principal nutrients in citrus fruits, such as vitamins C and E, folic acid, dietary fiber, and carotenoids, are thought to play a role in preventing or delaying the onset of major degenerative diseases (e.g., cancer, cardiovascular disease) by counteracting oxidative processes.

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• Cranberry• Cranberry juice has been used to treat urinary

tract infection, its effectiveness being attributable to the fact that it is rich in benzoic acid, which acidifies the urine.

• Cranberries evidently help to combat not only urinary infection but also several forms of cancer and heart disease.

• Antioxedant in cranberry prevent brain cell death.

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• Chocolate• Chocolate contains flavonoids such as ( – )

epicatechin which may promote cardiovascular health as a result of direct antioxidant effects or through antithrombotic mechanisms.

• Dark chocolate is better than milk chocolate in their total antioxidant capacity.

• Oats• β - glucan, like many other polysaccharides,

may reduce total and LDL cholesterol, thereby reducing the risk of CHD.

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• Ginger• ginger may lower the blood pressure or blood

sugar levels, which may reduce the need for blood pressure - lowering medicines or insulin.

• Avoid taking ginger with aspirin or other medicines that interfere with the clotting of blood

• also it increases the production of stomach acid, which would counteract the effect of anti - acid medications.

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• Ginseng• it is marketed to improve mental performance in

times of stress, to enhance overall health and vitality, to improve resistance to the damaging effects of stress

• Ginseng is used and marketed as a major tonic, stimulant, and immune booster.

• it can reduce blood sugar levels in people with type 2 diabetes (requiring especially careful glucose level monitoring).

• Avoid taking ginseng with aspirin or other medicines that interfere with the clotting of blood or with antidepressants, heart medication, insulin, or oral antidiabetic medicines. 227

Pumpkin seeds.• The pumpkin is one of the most popular seed

vegetables and is widely popular in Asia.• Pumpkin seeds are a good source of minerals,

amino acids, β - carotene, and antioxidants.• The seed oil has been shown to have broad -

spectrum antimicrobial and antifungal activity.• Pumpkin seed oil is also known to help in

arthritis, mainly in the chronic phase stage.• Pumpkin seed oil has also been shown to be

effective against hypercholesterolemia.228

• Reduction in the incidence of bladder stone by supplementation of pumpkin seeds for orthophosphate (60 mg/kg/day BW) has been reported.

• diets rich in pumpkin seeds could help in lowering the levels of gastric, breast, lung, and colorectal cancer.

• Groundnut seed ( Arachis h ypogea L .).• This seed is popularly known as the peanut,

monkey nut.• high in protein, energy, vitamins, and minerals

as well as for its oil 229

• Used in the preparation of peanut milk (a lactose - free milk - like beverage), peanut butter, and gluten - free flour.

• Peanut oil is exclusively used for cooking, has a mild flavor, is resistant to rancidity, and is stable even at high cooking temperatures.

• Peanuts are rich in nutritious antioxidant compounds, which are a good source of dietary fiber and have niacin (which contributes to brain health and blood flow), vitamin E, manganese, and phosphorus.

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• The seed and seed oil are free of trans fats and sodium.

• The seeds are reported to be a good source of active compound, which is known to possess significant anti - aging effects and to reduce cardiovascular disease and risks of cancer.

• Peanut consumption is reported to improve glutathione and high - density lipoprotein (HDL) cholesterol levels in experimental diabetes.

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• Coriander seeds• The seeds are extensively used as a seasoning

agent or as an ingredient in curry powder, cakes, breads, pastries.

• Coriander seeds are used medicinally for overcoming indigestion, rheumatism, and pain in the joints, and for treatment of worms or intestinal parasites.

• Available reports indicate seed volatiles (essential oil) to possess antibacterial and antioxidant activities.

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• Studies have indicated that coriander seeds display hypoglycemic action and affect the carbohydrate metabolism.

• Coriander seeds are also known to reduce blood pressure in laboratory animals and exhibit strong lipolytic activities.

• Recent reports have also indicated coriander seeds to cause diuresis in rats.

• Cumins eeds ( Cuminum c yminum L .).• Cumin seeds are rich in volatile oils, which

impart the characteristic aroma to the seed.233

• The seeds have antioxidant properties .• Showed reduction in hyperglycaemia

glucosuria along with lowered blood urea level and reduced excretions of urea and creatinine in diabetic animals

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Mushroom as Functional Foods• mushroom is a macrofungus with a distinctive

fruiting body.• The market value of medicinal mushrooms

and their derivative dietary supplements worldwide was about U.S.$1.2 billion in 1991 and about U.S.$3.6 billion in 1994.

• demand is increasing between 20 and 40% annually.

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• The moisture content of fresh mushrooms varies within the range 70–95% depending upon the harvest time and environmental conditions, whereas it is about 10–13% in dried mushrooms.

• protein content of edible mushrooms in general is about 4% and dry basis 19–35% protein

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• In addition to their good protein, mushrooms are a relatively good source of the following individual nutrients: fat, phosphorus, iron, and vitamins, including thiamine, riboflavin, ascorbic acid, ergosterol, and niacin.

• Low in Ca and carbohydrate.• Of the 14,000–15,000 species of so-called

mushrooms in the world, around 400 have known medicinal properties.

• medicinal mushroom products are derived from the fruiting bodies: such as

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• ß-D glucan.Antitumor and Immunomodulatory Activities• Polysaccharide bound peptide.• Dietary fibresIncrease mineral absorption.Fermented by gut microflora.

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Second exam

• 6-11-2013• Slide no. 101 - 238

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Vitamin D and Health• Vitamin D deficiency is now being recognized

as one of the most common medical conditions worldwide.

• The consequences of vitamin D deficiency include poor bone development and health as well as increased risk of many chronic diseases.

• The major source of vitamin D for most humans is exposure to sunlight.

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• Once vitamin D is made in the skin or ingested from the diet, it requires activation steps in the liver and kidney to form 25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D.

• A blood level of 25(OH)D <20 ng/ml is considered to be vitamin D deficiency, whereas a level 21–29 ng/ml is insufficient, and to maximize vitamin D’s effect for health, 25(OH)D should be >30 ng/ml.

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• The major physiologic role of vitamin D is to maintain intra- and extracellular calcium concentrations in order to maintain essential metabolic functions, which are important for most physiologic activities.

Traditionally known to prevent from Rickets. • A variety of endogenous factors and

environmental influences can alter the skin’s production of vitamin D, including skin pigmentation, sunscreen use, clothing, latitude, season, time of day, and aging.

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• sunscreen will absorb solar UVB photons, thereby significantly reducing the production of vitamin D3 in the skin by as much as 99%.

• Above the age of 65, there is fourfold decrease in the capacity of the skin to produce vitamin D3 when compared with a younger adult.

• Above and below latitudes of approximately 35◦ north and south, respectively, vitamin D synthesis in the skin is absent during most of the winter.

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• In the United States and Canada, milk is routinely fortified with vitamin D as are some bread products, orange juices, cereals, yogurts, and cheeses.

• In Europe, most countries do not fortify milk with vitamin D but many countries are fortifying cereals, breads, and margarine with vitamin D.

• Vitamin D is believed to control directly or indirectly up to 2,000 genes that are responsible for cell growth, angiogenesis, immunomodulation, vascular smooth muscle, and cardiomyocyte proliferation and inflammatory activities.

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Vit D and diseases prevention

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The Vitamin D Deficiency Pandemic• It has been estimated that upward of 30–50%

of both children and adults in the United States, Canada, Mexico, Europe, Asia, New Zealand, and Australia are vitamin D deficient.

• It is also extremely common in the most sunniest areas of the world including Mideast Countries including Saudi Arabia, Qatar, United Arab Emirates, Jordan Lebanon and India ranged (46 - 84 %)

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RECOMMENDED ADEQUATE DIETARY INTAKE OF VITAMIN D

Birth to 1 year:• after birth the infant can remain vitamin D sufficient

for several weeks as long as the mother was vitamin D sufficient.

• Human breast milk and unfortified cow’s milk have very little vitamin D.

• Thus, infants who are fed only human breast milk are prone to developing vitamin D deficiency especially during the winter when they and their mothers are not obtaining their vitamin D from exposure to sunlight.

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• Human milk and colostrums contains low amounts of vitamin D on average 15.9 ± 8.6 IU/L.

• lactating women given 4,000–6,000 IU vitamin D a day managed to transfer enough vitamin D in their milk to satisfy infants requirement.

• Infants require at least 400 IU of vitamin D to maximize bone health in the absence of sunlight exposure.

• But for reducing the risk of developing other disease such as type 1 diabetes, in Finland infants received 2000 IU decreased the incidence by 78%.

• The safe upper limit should be at least 2,000 IU/day.

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Ages 1–8 Years.• children are spending more time indoors, and

when they go outside, they often wear sun protection limiting their ability to make vitamin D in their skin (in developed countries).

• this age group needs at least 1,000 IU/day.• Therefore, recommendation 200 IU/day for

this age group should be increased to between 1,000 and 2,000 IU/day.

• The safe upper limit should be increased to at least 5,000 IU/day. 249

Ages 19–50 Years• At least 1,000 IU vitamin D/day and probably

1,500–2,000 IU/day is needed to maintain Vit D >30 ng/ml.

• The safe upper limit should be increased to at least 10,000 IU/day.

Ages 51–70 Years• Due to aging intestine ability decreases in

absorption of Vit D and Ca.• to maximize intestinal calcium transport that

the serum 25(OH)D needs to be >30 ng/ml.250

Pregnancy.• They should be taking at least a prenatal vitamin

containing 400 IU vitamin D with a supplement that contains 1,000 IU vitamin D.

• Thus, they need between 1,500 and 2,000 IU/day. The safe upper limit should be raised to at least 10,000 IU/day.

Lactation• lactating women should be on 1,500–2,000

IU/day and to satisfy the requirement of their infants, 4,000–6,000 IU/day may be needed.

• The safe upper limit should be increased to at least 10,000 IU/day. 251

Vitamin D and Chronic Diseases

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Vitamin D and the Risk of Type 1Diabetes

• Type 1 diabetes is a chronic disease which results from progressive autoimmune destruction of the insulin-secreting β-cells.

• Type 1 diabetes is a multifactorial disease, and both genetic predisposition and environmental factors are believed to be important in the development of the disease.

• There is no cure or preventive treatment for type 1 diabetes .

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• However, increased vitamin D intake is currently considered as one of the most promising candidates for prevention.

• MECHANISMS• In vitro studies and animal experiments have

shown that the active form of vitamin D affects T-cell activity, which could potentially influence various stages of the autoimmune process leading to type 1 diabetes.

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• STUDIES IN HUMANS• no published clinical trials investigating the

role of vitamin D in the prevention of type 1 diabetes.

• observational studies such as EURODIAB project reporting data from seven European countries on the association between vitamin D supplementation in infancy and diabetes risk suggested a 33% reduction (OR 0.67) in the subsequent risk of developing type 1 diabetes for vitamin D supplementation during the first year of life.

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• Northern Finland: • Infants who had received vitamin D

supplementation regularly during the first year had 88% lower risk of type 1 diabetes by age 31 compared to participants receiving no supplementation.

• It is well known that type 1 diebetic people are lower in circulating Vit D .

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Vitamin D and Type 2 Diabetesimpaired pancreatic function or insulin resistance

• Epidemiologic data suggest that 9 out of 10 cases of type 2 diabetes could be attributed to modifiable habits and lifestyle.

• The total number of people with diabetes worldwide is expected to rise from 171 million in 2000 to 366 million by 2030.

• Recently, there has been increasing evidence from animal and human studies to suggest that vitamin D may be important in modifying risk of type 2 diabetes. 257

• POTENTIAL MECHANISMS• vitamin D restores insulin secretion by direct

effect on beta-cell function.• An indirect effect of vitamin D on the beta cell

may be mediated via its regulation of calcium concentration . Insulin secretion is a calcium-dependent process.

• Vitamin D affects the chemicals secreted by cells to resist insulin.

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• Human studies:• In Finland, men have higher serum level of Vit

D and lower risk of type 2 diabetes. • In a prospective study – women with the

highest vitamin D intake (>800 IU/day) had a 33% lower risk of incident type 2 diabetes compared to women with the lowest vitamin D intake (<200 IU/day).

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Role of Vitamin D for Cardiovascular Health

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