Anthocyanin n flavonoid
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Transcript of Anthocyanin n flavonoid
Anthocyanins and Flavonoids
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Senyawa Fenol
1. Flavonoid : flavonol,flavanol,
flavanone,isoflavone,anthocyanin, dll
2. Asam phenol: asam elagat, asam tannat,
vanilin, dll
3. Asam Hidroksisinamat : asam kafeat, asam
klorogenat dll
4. Lignan
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Anthocyanin food color
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Anthocyanins
• Orange-red, red-blue colors
• Foods: strawberries, berries(blueberries, cherries, blackberries), grapes and some vegetables, such as egg-plant and avocado.
• Water soluble – form hydrogen bonds with water due to the presence of multiple hydroxyl groups.
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•natural acid-base indicators. • structure: Three phenol groups (benzene ring) with conjugated carboncarbon bonds and varyingnumbers of hydroxyl groups.•Glucose molecules bond to the oxygen atom on the second phenol group. •Anthocyanins are found in foods high in sugar content.
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Structure of Anthocyanin
Anthocyanin pigment is composed of aglicone (an anthocyanidin) esterified to one or more sugar
Aglicon/anthocyanidin
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• OH-more
bluish
• methoxyl groups
more redness
Effect of Substituents on the Color of Anthocyanidins.
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Anthocyanin at different pH
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O
OGlucose
OH
R
OH
R
OO+
OGlucose
OH
R
OH
R
HO
O+
OGlucose
OH
R
OH
R
OO+
OGlucose
OH
R
OH
R
HO
OH
BLUERED
COLORLESS COLORLESS
+H+
-H2O
-H+
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Stability of Anthocyanin
Unstable with -pH, -temperature -UV light and Fe3+ & Al 3+ ions. -high temperature during cooking, anthocyaninsdecompose
Most stable -at low pH (acid) - low temperature.
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At The position of equilibrium moves to the right, colorless.
- Blue quinonoidal base (A), stable at pH 6-7
- Red flavylium cation (AH+), stable at pH 1-2
- Colorless carbinol psuedobase (B), stable at pH 4-5
Colorless chalcone (C), stable at pH > 7 brown products
This is the reason that most colorants containing anthocyanins can
only be used at pH values < 4
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Anthocyanin can reacts with a bisulfite ion to form a
colorless 2-bisulfite adduct product
Ex: jams, dried fruits & dried vegetables
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FLAVONOID
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Flavonoid
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FLAVONOID
The basic flavonoid skeleton can have a large number of substitutions on it:-Hydroxylgroups-Sugars-e.g. glucose, galactose, rhamnose. most structures are glycosylated-Methylated-Acylated
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Sugars and hydroxyl groups increase the water solubility of flavonoids-Methyl and isopentyl groups make flavonoidslipophilc-If no sugar-AGLYCONE-With sugar-GLYCOSIDE
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Structures are very similar to those of anthocyanidins: But no positive charge on the oxygen atom and no double bonds in the C ring .
1. FlavAnols
Flavan-3-olAnthocyanidin
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FlavAnols: Catechin & Epicatechin
Green tea, Cocoa powder, Red wine
1. Powerful antioxidants2. Have beneficial effects on cardiac health, immunity and longevity
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2. FlavOnols
-The molecule has a double-bonded oxygen atom attached to position 4 (that’s why flavOnols). -They're still "-ols" because they retain the -OH group at position 3 like the flavAnols-The double-bonded oxygen atom, makes them like another class of flavonoids known as "flavones" (next)-Double bond in between C2 and C3 (C ring)
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FlavOnols
Example: •Quercetin in Onions•antioxidant effects
FlavOnols are mostly found as O-glycosides-
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3. FlavOnes
-Close to the flavOnols but not so widespread (celery, parsley and some herbs)-BUT Without the "-ol." there is no longer an -OH group at position 3 on the central ring
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4. Flavanones
High concentrations in citrus fruit
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Flavanones-No double bond between carbons 2 and 3 of the flavonestructure, and chiral center (C2)-A highly reactive structure ( a lot of substitutions)
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Flavanones-Ex. :Naringenin-An antioxidant flavanone from citrus species
-anti-inflammatory, anti-cancer, and liver protective effects
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5. Isoflavones (Isoflavonoids)
-Very similar to flavones, except that the B ring is attached to position 3 of the C ring, rather than to position 2 as in the flavone
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Isoflavones (Isoflavonoids)
-Found in leguminous plants (ex.: soybean)-Genistein, daidzein-phyto-oestrogens (can effect reproduction )
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Antioxidant activity
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1. Tanin terhidrolisis: td dari asam fenolatdan gula yg bisa di pecah dg asam, alkali dan enzim.
2. Tanin non-hidrolisis atau taninterkondensasi atau proanthocyanidins
Tannins
•present in the skins of red grapes •Have roles in the flavor profile of red wine.•Tanin bind proteins alivary to give astringency taste•Astringency also found in tea, wine
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