Jpn. J. Trop. Agr. 47(4) : 243 -249, 2003

Analysis of Chemical Components and Oxygen Radical

Absorbance Capacity of Tamarind us indica L.

Syeda Shahnaz PARVEZ1,2,*, Mohammad Masud PARVEZ2, Yoshiharu FUJII2 and Hiroshi GEMMAI

1 Laboratory of Pomology, Institute of Agriculture and Forestry, University of Tsukuba, 1-1-1 Tennodai, Tsukuba Science City, Ibaraki, 305-8572, Japan2 Chemical Ecology Unit, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba Science City,

Ibaraki, 305-8604, Japan.* Correspondence: Chemical Ecology Unit National Institute for Agro-Environmental Sciences 3-1-3 Kannondai , TsukubaScience City Ibaraki 305-8604 Japan Tel: +81-29-838-8246 Fax: +8129-838-8338 E-mail: ssparvez@yahoo. com

Abstract A comparative study was carried out to evaluate the characteristics of ripened tamarind fruits collected from 5

different countries - Bangladesh, India, Pakistan, Philippines and Thailand in South-East Asia. Physiological development of

tamarind fruit, proximate chemical composition, total sugar content, mineral components, antioxidant activity and phenolics

of ripened fruit pulp were analyzed. Moisture content of the ripened fruits was ca 20%. Proximate composition, energy

value, sugar content and mineral components were expressed as 100 g DW-1 (dry weight) of the tamarind fruit pulp. The

amounts of crude protein, crude lipids, crude fibers, ash and total crude carbohydrates were 8.5 to 9.1, 2.7 to 3.1, 2.8 to 3.4,

2.9 to 3.3 and 82.1 to 82.6 g, respectively. The energy values ranged from 1539 to 1581 KJ and the total sugar content varied

between 46.5 and 58.7 g. Among the analyzed mineral components, the amounts of Mg (25.6 to 30.2 mg) and Na (23.8 to

28.9 mg) were found to be highest, while the lowest amounts were recorded for Cu (0.8 to 1.2 mg) and Zn (0.8 to 0.9 mg).

The values for the antioxidant activity expressed by the oxygen radical absorbance capacity (ORAC) and the total phenolic

content (TPC) in the tamarind fruit pulp tested ranged from 59.1 to 66.3ƒÊmol of Trolox equivalent (TE) g DW-1 and 626.6

to 664.0 mg of gallic acid equivalent (GAE) 100 g DW-1, respectively. Strong positive correlations (>0.99 at the 1% level of

probability) between ORAC and TPC were observed, suggesting that the increased antioxidant activity (hereafter referred

as •gantioxidant capacity•h) due to high phenolics in tamarind fruit could provide protection against certain human

degenerative conditions associated with oxygen free radical damage. Our study is the first attempt to measure ORAC and

TPC, and to examine their relationship in ripened tamarind fruits collected from 5 different countries in South-East Asia.

Finally, it appeared that tamarind fruit contains a biologically important source of mineral elements, shows a high

antioxidant capacity and high levels of phenolics. Tamarind fruit or food-products from tamarind fruit pulp may act as

functional foods whose consumption is associated with specific beneficial effects on human health.

Key Words: Antioxidant capacity, Mineral Component, Sugar Content, Tamarind, Total Phenolic Content (TPC)

タマ リン ドの 成 分分 析 と活 性 酸素 ラ ジ カル 消去 能 Syeda Shahnaz PARVEZ 1,2・Mohammad Masud PARVEZ2・ 藤 井 義 晴2・

弦 間 洋11筑 波 大 学 農林 学 系 〒305-8572つ くば市 天 王 台1-1-12独 立 法 人農 業 環 境技 術 研 究 所 〒305-8604つ くば市

観 音 台3-1-3

要 約 バ ング ラデ シュ,イ ン ド,パ キス タン,フ ィ リピン,タ イの5力 国か ら収集 したタマ リン ド成熟果実の成分分析 を行 った.

可食部の水分 含量は約20%で,乾 物100g当 た り粗 タンパ ク質 は8.5～9.1g,脂 質 は2.7～3.1g,繊 維 は2.8～3.4g,炭 水化物 は82.1～82 .69,カ ロ リーは1,539～1,581KJの 範囲 を示 し,全 糖 質含量は46.5～58.79で あった.構 成 無機 質の うち,高 含 量はMg(25.6～30 .2mg)とNa(23.8～28.9mg)で, Cu(0.8～1.2mg)とZn(0.8～0.9mg)の 含 量 は 低 か っ た.活 性 酸 素 ラ ジカ ル消 去 能

(ORAC)と 総 フェノール含量 を計測 したところ,そ れ ぞれ乾物1g当 た りTrolox当 量で59.1～66.3μmol,乾 物100g当 た り没 食子

酸 当量 で626.6～664.0mgを 示 した.両 者間 には強 い相 関が見 られ た(>0.99,1%レ ベル)こ とか ら,高 フェ ノール含量の タマ リン

ド果実 は,活 性酸素 ラジカルによ る生体の酸化障害 か ら保護す る機能 を有 する と思われた.こ の よ うに タマ リン ド果実 は ミネラル補

給,さ らには高 フェノール含量 に基 づ く抗酸化性 など貴重 な食料資源で あることが明 らかに された.本 報 はタマ リン ド,と くに東 南

アジア周辺 国で収集 した果実の抗酸化性 に言 及 した初めて の報告 であ り,今 後,タ マ リン ド果実あ るい はその加工食 品が,生 体調 節

機能 をもつ機 能性食品 として利用 され るであ ろう.

キーワー ド 抗 酸化性,構 成無機質,総 フェ ノール量,タ マ リン ド,糖 含量

Introduction

Botanical nomenclature of tamarind (Tama-rindus indica L., family Leguminosae) fruit tree

suggests that the tree is native to India. In fact, it is a tropical African native evergreen species which is distributed in most of the tropical countries around the world with the largest cultivated area being located in India (EL-sIDDIG et al. 2000, PARVEZ et al. 2003). Tamarind is a tall

Received May 21, 2003Accepted Aug. 25, 2003

244 Jpn. J. Trop. Agr. 47 (4) 2003

tree (15 to 20 m) with a compact rounded trunk and clear drooping branches (Fig. 1A-B) producing an average yield of 150 to 500 kg fruits per tree

per year (SHANKARCHARYA, 1998). The tree remains productive for more than 50 years and survives up to 200 years (BUESO, 1980). International survey of unexploited tropical and subtropical

perennials showed that tamarind is cultivated on an orchard scale in the Caribbean, Central America, South America, South-Central Asia and South-East Asia (SEDGELY and GARDNER, 1989). In Bangladesh, Belize, India, Indonesia, Philip-

pines, Mexico, Myanmar, Sri Lanka, Thailand and Vietnam commercial planting for fruit harvesting is implemented (BHATrACHARYA et al. 1994; MORTON, 1987; CsIR, 1976).

Ripened tamarind fruit is of the indehiscent type, shows curved-shaped pods 12-15 cm long and 3 to 5 cm wide (Fig. 1C-D). The fruit consists of seeds (33.9%), pulp (55.0%), and shell and fibers (11.1%) (RAO and SRivASrAvA, 1974). The outer shell which is woody, fragile and shows a scurfy brown color (Fig. 1E) covers a brown fruit pulp with dark brownish-black hard

and shiny seeds (Fig. 1F) inside the pulp. Most of the countries in South-East Asia grow tamarind tree mainly for its fruits and the pulpy portion of the fruit has been used extensively for culinary

preparations for a long time, as well as for medicinal and industrial applications. Presently, in many countries, the fruit is processed to

prepare beverages, nectar, juice, concentrates, flavor products, sauces, etc.

Occurrence of and mortality rates due to cancer and heart diseases have been reported to be strongly correlated with the consumption of fruits and vegetables (AMEs et al. 1993; DRAGSTED et al. 1993; WILLFTT 1994; WANG et al. 1996). The protection that fruits and vegetables confer against these diseases has been attributed to their contents of various antioxidants and

phenolics (GEY, 1990; STEINBERG, 1991). Tamarind fruit pulp is brown in color and rich in acid which enables to extend the period of storage without any refrigeration and to maintain the original strong aromatic flavor profile (BUESO, 1980), hence, the increased popularity as food

preservative (TSUDA et al. 1994) and as a drug

Fig. 1. Tamarind tree, fruits and different parts; (A) tamarind tree, (B) trunk, (C) whole tamarind fruit, (D) tamarind fruit pulp, (E) outer shell of fruit, and (F) seeds.

Parvez et al.: Analysis of Tamarindus indica L. fruit 245

(MUSTAPHA et al. 1996). LEWIS and co-workers

(1961) reported that anthocyanins and high

levels of polyphenols are accumulated in the

tamarind fruit pulp.

To our knowledge, no comparative studies on

tamarind fruits from different growing countries

had been conducted. Therefore, in order to gain

information on the proximate chemical composi-

tion, total sugar content, mineral components,

antioxidant capacity and total phenolic contents

in ripened fruits, we analyzed ripened tamarind

fruits collected from 5 different developing

countries - Bangladesh, India, Pakistan, Philippines

and Thailand in South-East Asia. We also

examined the nutritive value of tamarind fruits,

with emphasis placed on the importance of

maintaining sound health and preventing diseases.

Materials and Methods

Plant material

Ripened tamarind fruits were collected from

3 different trees grown either in home gardens

or in the fields of agricultural research stations

at 3 different locations in each of 5 different

countries - Bangladesh (Comilla, Dhaka and

Jessore), India (Assam, Delhi and West Bengal),

Pakistan (Islamabad, Karachi and Lahore),

Philippines (Cebu, Manila and Mindanao) and

Thailand (Bangkok, Chiang Mai and Phuket).

Freshly harvested ripened fruits from the trees

were freeze-dried and stored at -80•Ž until

further analysis. All the collected and analyzed

samples belonged to the sour type of tamarind.

Moisture content determination

The moisture content was determined by

keeping fruit samples in a paper bag at 70•Ž in

an oven (Ikeda Rica Co. Ltd., Japan) for 24 h.

The difference in weight was calculated on a

percentage basis and expressed as the moisture

content. Results were presented as means of

three replications.

Processing

Edible part (pulp) of the tamarind fruit was

carefully taken out after peeling off the outer

shell and removing the inner seeds. The pulp

was homogenized using a mortar and pestle for

the component analysis according to standard

protocols. Results were presented as means of

three replications.

Proximate and nutritional component analysisNitrogen content was estimated by the

micro-Kjeldahl method (HUMPHRIES, 1956). The analysis of the proximate chemical composition and the total sugar content in tamarind fruit

pulp was carried out according to the standard methods of AOAC. The amounts of total crude carbohydrates were calculated as follows: [100 -

(amount of crude protein + amount of crude lipids + amount of crude fibers + amount of ash)] according to the method of MULLER and TOBIN (1980). The energy value was obtained according to the standard method of OSBORNE and VOOGT (1978).

Mineral composition (except for P) was determined according to a standard protocol

(OSBORNE and VOOGT,1978) using an atomic absorption spectrophotometer (Z-8100, Polar-ized Zeeman, Hitachi, Japan). We adopted the method of DICKMAN and BRAY (1940) for the determination of P. Each experiment was conducted three times and the results were presented as means of three replications on a dry weight

(DW) basis.

Measurement of antioxidant capacityThe antioxidant capacity in tamarind fruit

pulp was measured as oxygen radical absorbance capacity (ORAC) according to the method of CAO et al. (1993). Each experiment was conducted three times and the results were presented as means of three replications and expressed in imol of Trolox equivalent (TE) per gram of dry weight (DW) of fruit pulp.

Total phenolic compound analysisThe total phenolic content (TPC) in the

tamarind fruit pulp was determined according to the method of SINGLETON and ROSSI (1965) using the Folin-Ciocalteu reagent with gallic acid as a standard. Each experiment was conducted three times and the results were presented as means of three replications and expressed in milligrams of gallic acid equivalent (GAE) per 100 g of dry weight (DW) of fruit pulp.

Results and Discussion

The values of the moisture content in the ripened tamarind fruits from 5 different countries are shown in Table 1. We found that the moisture content of the tamarind fruits did not vary significantly with the country of origin and

246 Jpn. J. Trop. Agr. 47 (4) 2003

ranged from 18.4 to 21.0%. Fruit samples from Bangladesh and India showed moderate values

(19.6 to 20.1%) while the lowest values were recorded in the fruits from Pakistan (18.4%) and the highest values were recorded in the Philippines (21.0%) (Table 1). In a previous study using the edible part of tamarind fruit

pulp samples from three African countries the moisture content was slightly higher than our observation (27%) (SAKA and MSONTHI,1994). In fact, the moisture content at the maturation stage was too high (60 to 80%) (data not shown) and due to the rapid reduction in the moisture content (ca 20%) at the ripening stage, physiological separation of the outer shell and pulp inside the

pod occurred.Proximate composition including crude

protein, crude lipids, crude fibers, ash, total crude carbohydrates and energy value in the

pulp of ripened tamarind fruits collected from 5 different countries is shown in Table 1. The amount of component was expressed in g 100 g DW-l (dry weight). Among the analyzed proximate chemical components, the amount of crude

protein was the highest (7.8 to 9.1 g). The amounts of other components like crude lipids, crude fibers and ash did not vary among the

fruits from different countries and were within a range of 2.7 to 3.4 g (Table 1). The calculated content of total crude carbohydrates was ca 82 g

(Table 1). Furthermore, the energy value ranged in between 1539 and 1581 KJ (Table 1).

Table 1 shows the total sugar content in the

pulp of tamarind fruits collected from 5 different countries. The amount of total sugar ranged between 46.5 and 58.7 g 100 g DW-l of fruit pulp. The samples from the Philippines and Thailand were found to contain a higher amount of total sugar than the other tested samples.

Table 2 shows the mineral composition analysis of the pulp of ripened tamarind fruits collected from 5 different countries. A total of 8 different types of minerals were identified under our experimental conditions. All the values were expressed in mg 100 g DW-l (dry weight). The amounts of Mg (25.6 to 30.2 mg) and Na (23.8 to 28.9 mg) were the highest while the lowest amounts were recorded for Cu (0.8 to 1.2 mg) and Zn (0.8 to 0.9 mg) among the identified components. The amounts of P, K, Ca and Fe ranged between 9.2 to 10.3, 6.8 to 8.7, 3.3 to 3.7, and 1.3 to 1.8 mg, respectively. Lower values for most of the mineral components (except for P) in the tamarind fruit pulp than those we

Table 1. Proximate composition analysis of the pulp of ripened tamarind fruits from 5 different countries.

All the values are means of triplicate samples and expressed on a dry weight (DW) basis.

•} indicates standard errors.

Table 2. Mineral composition analysis of the pulp of tamarind fruits from 5 different countries.

All the values are means of triplicate samples and expressed on a dry weight (DW) basis.

•}indicates standard errors.

Parvez et al.: Analysis of Tamarindus indica L. fruit 247

recorded had been reported in the samples from Nigeria and Malawi (ISHOLA et al. 1990; SAKA and MSONTHI, 1994). However, our results were well correlated with recent findings using samples from Pakistan (MIRZA et al. 1998). The amount of P obtained in our samples was identical with that reported by several authors

(SAKA and MSONTHI, 1994). Compared with other major fruits, it appears that the tamarind fruit pulp contains a considerable amount of various mineral elements, particularly Mg, Na, PandK.

Vitamins and minerals play a key role in adequate maintenance of human health. Like vegetables, fruits provide these elements abundantly in nature. A number of health-related disorders have been reported either in the case of deficiency or excess of minerals. For example, Cu, Mn, Zn, Fe, Ca, Mg and K are involved in the neurochemical transmission process, and also act as co-factors for a number of enzymes in various metabolic pathways. Furthermore, Fe is an important element against malnutrition,

particularly in children and pregnant women, and the beneficial role of Fe has been reported in erythropoiesis and oxygen transport in cells

(WILLIAM, 1991). Cu and Zn which are the constituents of many metallo-proteins reduce mental anxiety, stress and depression (ANDRASI et al. 1990). Zn also enhances the intellectual ability (CHAKARBARTI et al. 1980).

The antioxidant activity (ORAC) and the total phenolic contents (TPC) in the pulp of ripened tamarind fruits collected from 5 different countries and the correlation coefficients between these two parameters are presented in Table 3. No significant differences in the values of these two parameters were observed among the locations. The values for ORAC and TPC ranged

from 59.1 to 66.3 ƒÊ mol of Trolox equivalent (TE) g

DW-1 and 626.6 to 664.0 mg of gallic acid

equivalent (GAE) 100 g DW-1, respectively. High

values for TPC in tamarind fruit suggested that

the fruit could be preserved over a long period

of time without any change in flavor and color

profile or insect-pest attacks due to the high

content of organic acids and could be used for

food preservation and medicinal purposes. In

fact, tamarind fruit is remarkably free from

diseases and such a strong resistance has been

attributed to the high polyphenol content (LEWIS

et al. 1961). Under our experimental conditions,

high positive correlations (>0.99 at the 1% level of

probability) were found between ORAC and TPC

in the samples from each country, corresponding

to recent findings in tea and several common

vegetables (CA0 et al. 1996), various berry fruits

and small fruits (WANG et al. 2000; KALT et al.

2001).

For more than 100 years, synthetic antioxidants

such as butylated hydroxyanisole (BHA) and

butylated hydroxytoluene (BHT) have been

used as food preservatives (WANG and UN,

2000). However, it is assumed that these

compounds cause liver damage and an carcinogenic

(ITO et al. 1983) . Thus, the interest and attempts

to identify natural antioxidants from plants have

considerably increased in the past decades. On

the other hand, phenolic compounds exert

multiple biological effects, including antioxidant

activity and are commonly found in plants.

There is an increasing demand for fruits,

vegetables, herbs and cereals rich in phenolics

in the food industry due to their ability to delay

the oxidative degradation of lipids (KAHKONEN et al.

1999). Consumption of controlled diets compris-

ing fruits and vegetables (that contain a high

amount of flavonoids and phenolics) has led to a

Table 3. Oxygen radical absorbance capacity (ORAC), total phenolic content (TPC) and relationship between these two parameters in the pulp of ripened tamarind fruits from 5 different countries.

All the values are means of triplicate samples and expressed on a dry weight (DW) basis.

•} indicates standard errors.

248 Jpn. J. Trop. Agr. 47 (4) 2003

significant increase in the antioxidant capacity in the plasma, thus, playing a key preventive role against cancer and heart diseases (CAO et al. 1998; KAHKONEN et al. 1999). Consumers, food

producers, food product manufacturers and scientists are increasingly interested in includ-ing antioxidant constituents in human foods from plant materials for proper health mainte-nance and fatal disease prevention.

Conclusion

We conclude that under our experimental conditions, the proximate composition, nutrient

components, antioxidant capacity and phenolic contents of the pulp of ripened tamarind fruits collected from 5 different countries in South-East Asia showed almost identical values except for certain elements. However, the values of most of the components related to proximate and nutritional analysis in tamarind fruit pulp reported in several African countries were significantly lower than those we observed. Such a difference might be due to the combined effects of tamarind tree cultivars, soil conditions

(nutrient content, type, texture, etc.), climatic conditions, ecological context, and geographical locations as a whole, and studies related to these aspects should be conducted in future. The determination of ORAC and TPC and the relationship of these parameters demonstrated in our studies on the ripened tamarind fruits from different geographical locations had never been reported in the literature, to our knowledge. Observation of strong positive correlations between ORAC and TPC in tamarind fruits suggested that the increased antioxidant capacity due to the high content of phenolics in the fruit could provide

protection against certain human degenerative diseases associated with oxygen free radical damage. Apple and grapes, for example, display a strong antioxidant capacity mainly due to the high content of phenolic compounds, particu-larly anthocyanins. Since larger amounts of anthocyanins accumulate in the skin of both fruits than in the flesh, the latter show lower ORAC and TPC values than the former,

presumably due to the fact that most of the phenolic compounds are discarded when the fruits are consumed without any skin, generally. However, the whole portion of the analyzed tamarind fruit pulp is readily edible since it is devoid of seeds or shell. Therefore, the higher

values of ORAC and TPC in tamarind fruit pulp imply that the fruit has a high antioxidant capacity and that the consumption of tamarind fruit would be possible without any loss of

phenolics. Tamarind as a fruit is commonly consumed and also used as a drug and food-

preservative in many Asian and African countries. The use of food products made from tamarind fruit pulp and as an ingredient of many food

products like cakes, chocolate, ice-cream, jelly, etc. has been increasing in many developed and developing countries. Considering the mainte-nance of health and prevention of diseases, there is a growing awareness and significance of the beneficial effect of the consumption of fruits and vegetables as daily human dietary components. It is evident that tamarind fruit is a biologically important source of mineral elements, shows a high antioxidant capacity and high levels of

phenolics. We consider that the consumption of tamarind fruit would meet the daily dietary requirements in terms of recommended amount. In addition, the results obtained will allow food makers to produce different kinds of improved food products with a high nutritive value from tamarind fruit pulp.

Acknowledgement

The authors express their gratitude to a number of anonymous researchers from different countries who provided the samples. This work was supported in part by a scholarship awarded to S.S.P. from the College Women's Association of Japan (CWAJ) which is gratefully acknowl-edged.

References

AMES, B. M., M. K. SHIGENA and T. M. HAGEN 1993 Oxidants, antioxidants and the degenerative diseases of aging. Proc. Natl. Acad. Sci. USA. 90: 7915-

7922.ANDRASI, E., J. NADASHI, Z. MOLNAR, L. BEZUR and L.

ERYNEIL 1990 Determination of main and trace elements in human brain by Neuron Activation Analysis (NAA) and Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) methods.

Bio Trace Elements Res. 26-27: 691-698.BHATTACHARYA, S., S. BAL and R. K. MUKHERJEE 1994

Functional and nutritional properties of tamarind (Tamarindus indica) kernel protein. Food Chem.

49:1-9.BUESO, C. E. 1980 Soursop, tamarind and chironja. In:

Tropical and subtropical fruits. (Eds Nagy S. and

Parvez et al.: Analysis of Tamarindus indica L. fruit 249

Shaw P. E.). AVI, Westport, Conn. pp. 375-406.CAO, G., H. M. ALESSIO and R. G. CUTLER 1993 Oxygen-

radical absorbance capacity assay for antioxidants. Free Radical Biol. Med. 14: 303-311.

CAO, G., E. SOFIC and R. L. PRIOR 1996 Antioxidant capacity of tea and common vegetables. J. Agric. Food Chem. 44: 3426-3431.

CAO, G., S. L. BOOTH, J. A. SADOWSKI and R. L. PRIOR 1998 Increases in human plasma antioxidant capacity after consumption of controlled diets high in fruit

and vegetables. Am. J. Clin. Nut. 68:1081-1087.CHAKRABARTI, A., N. L. BANIK, J. M. POWER and E. L..

HOGAN 1980 The regional and subcellular distribution of calcium activated neutral proteinase (Ca, N,P) in bovine central nervous system. Neurochem Res. 14: 259-266.

CSIR (Council of Scientific and Industrial Research) 1976 The wealth of India: Raw materials, New Delhi, India. 10: 118-122.

DICKMAN, S. R. and R. H. BRAY 1940 Colorimetric determination of phosphate. Ind. Eng. Chem. Ed.

12: 665-668.DRAGSTED, L. O., M. STRUBE and J. C. LARSEN 1993 Cancer-

protective factors in fruits and vegetables: biochemi-cal and biological background. Pharmacol. Toxicol.

72:116-135.EL-SIDDIG, K., G. EBRET and P. LUDDERS 2000 Emergence

and early seedling growth of Tamarindus indica L. from geographically diverse populations in the Sudan.

J. Applied Bot. 74:17-20.GEY, K. F., P. PUSKA, P. JORDAN and U. K. MOSER 1991

Inverse correlation between plasma vitamin E and mortality from ischemic heart disease in cross-

cultural epidemiology. Am. J: Clin. Nutr. 53: 3265-334S.HUMPHRIES, E. C. 1956 Mineral composition and ash

analysis. In: Modern methods of plant analysis (Eds Peach K. and Tracey M. V.). Vol. 1, Springer-Verlag, Berlin, Germany. pp. 468-502.

ISHOLA, M. M., E. B. AGBAJI and A. S. AGBAJI 1990 A chemical study of Tamarindus indica (Tsamiya)

fruits grown in Nigeria. J. Sci. Food. Agric. 51: 141-143.

ITO, N., S. FUKUSHIMA, A. HASEGAWA, M. SHIBATA and T. Ogiso 1983 Carcinogenicity of butylated hydroxy anisole in F344 rats. J. Natl. Cancer Inst. 70: 343-347.

KAHKONEN, M. B, A. I. HOPIA, H. J. VUORELA, J. RAUHA, K. PIHLAJA, T. S. KUJALA and M. HEINONEN 1999 Antioxidant activity of plant extracts containing

phenolic compounds. J. Agric. Food Chem. 47: 3954-3962.

KALT, W., A. HOWELL, J. C. DUY, C. F FORNEY and J. E. MCDONALD 2001 Horticultural factors affecting antioxidant capacity of blueberries and other small fruit. Hort Tech. 11: 523-528.

LEWIS, Y. S., S. NEELAKANTAN and D. S. BATHIA 1961 Organic acid metabolism in Tamarind leaves. Curr.

Sci. 30: 381-382.MIRZA, M., Z. YAQEEN, Yaqeen-Uddin, M. Qadir-Uddin and

Y. BANAL 1999 Trace elements in Tamarindus indica L. and their nutritional importance. Pak. J. Sci. Ind.

Res. 41: 310-311. MORTON, J. F. 1987 Tamarind. In: Dowling C.F (Eds)

Fruits of the warm climates. Published by Morton J. F., 20534 SW 92 Ct. Miami, FL 33189, USA. pp. 115-121.

MULLER, H. G. and G. T00BIN 1980 Nutrition and Food Processing. Croom Helm, London, UK.

MUSTAPHA, A., I. A. YAKASAI and I. A. AGUYE 1996 Effect of Tamarindus indica on the bio availability of aspirin in

healthy human volunteers. European J. Drug Metabolism Pharmacokinetics. 21: 223-226.

OSBORNE, D. R. and P. VOOGT 1978 The analysis of nutrients in foods. Academic Press, London, UK. pp. 251.

PARVEZ, S. S., M. M. PARVEZ, E. NISHIHARA, H. GEMMA and Y. FUJII 2003 Tamarindus indica L. leaf is a source of allelopathic substance. Plant Growth Regul. 40: 107-115.

RAO, P. S. and H. C. SRIVASTAVA 1974 Tamarind. In Industrial Gums, ed. R. L. Whistler. Academic Press, NY, USA. pp. 370-411.

SARA, J. D. K. and J. D. MSONTHI 1994 Nutritional value of edible fruits of indigenous wild trees in Malawi. Forest Eco. Management. 64: 245-248.

SEDGLEY, M. and J. A. GARDNER 1989 International survey of unexploited tropical and subtropical perennials.

Acta Hort. 250: 1-2.SIIANKARCHARYA, N. B. 1998 Tamarind - chemistry, technology

and uses - a critical appraisal. J. Food Sci. Technol. 35:193-208.

SINGLETON, V. L. and J. A. Rossi 1965 Colorimetry of total

phenolics with phosphomolybdic-phosphotungstic acid reagent. Am. J. Enol. Vitic. 16: 144-158.

STEINBERG, D. 1991 Antioxidants and atherosclerosis: a current assessment. Circulation. 84:1420-1425.

TSUDA, T, K. MIZUNO, K. OHSHIMA, S. KAWAKISHI and T OSAWA 1994 Super critical carbon-dioxide extraction of antioxidant components of Tamarind (Tamarindus indica L.) seed coat. J. Agric. Food Chem. 43: 2803-2806.

WANG, H., G. CAO and R. L. PRIOR 1996 Total antioxidant capacity of fruits. J. Agric. Food Chem. 44: 701-705.

WANG, S. Y. and H. UN 2000 Antioxidant activity in fruits and leaves of blackberry, raspberry and strawberry varies with cultivar and developmental stage. J. Agric. Food Chem. 48:140-146.

WILLIAM, F. F. 1991 Review on Medical Physiology. Appleton and Lange, California, 14th Edition. pp. 76-215.

WILLETT, C. W. 1994 Diet and health: what should we eat? Science. 264: 532-537.