polyphenols are widespread in ___
plants
in the past, focused on polyphenols cuz ___, and now for ___
antinutritional effects; beneficial health effects as antioxidants
examples of polyphenols?
tannins (antioxidant), ellagic acid (anticarcinogen)
common structural features of polyphenols:
conjugated aromatic ring with at least 2 hydroxy substituents
classes of polyphenols:
flavonoids (major), phenolic acids, lignans
example of a phenolic acid?
caffeic acid
antiox activity of polyphenols influenced by:
1) # and position of OH groups 2) extent of conjugated double bonds 3) lipid/aqueous solubility 4) ability bind metals
what is French paradox?
even though eat lots of cheese/foie gras and smoke, still low incidence of heart disease (is it because of red wine??)
diff factors that influence diet intake of polyphenols
plant genes/enviro conditions, ripeness, processing/storage
___ browning causes oxidation of polyphenols
enzymatic
how to prevent enzymatic browning?
acid (denature enzymes causing browning) and vit c (re-reduce oxidation of polyphenols)
absorption of polyphenols influenced by degree of ___
glycosylation
glucose enhances ___ absorption, other sugars ___ absorption
quercetin; inhibit
some polyphenols and condensed tannins have ____ effect in rats
hypercholesterolemic
polyphenols can decrease post prandial _____ response by inhibiting enzymes
glycemic
what is CBG?
cytosolic beta glucosidase
what is COMT?
catechol-O-methyltransferase
what is UDPGT?
UDP glucuronyl transferase
what is SULT?
phenol sulfotransferase
identified in 1930s by Albert
flavonoids
flavonoids work together with ____ to prevent capillary permeability
vitamin C
differences in flavonoids come from diffs between ____
c-ring (mid ring)
diff between flavone and isoflavone?
presence of R group in isoflavone
proanthocyanins similar to ____ not anthocyanins
catechins
proanthocyanidins are also called:
condensed tannins
__ have bitter taste, ___ have astringent taste, ___ have natural dyes
flavones/flavanones; flavanols; antocyanins
how does antiox activity work?
ability donate H atom from aromatic hydroxyl group to free radical
how does flavonoid be anti-inflammatory?
inhibit NfkB activation, inhibit enzymes
flavonoid effect on cancer:
antiproliferative, pro-apoptotic, anti-inflamm, anti-angiogenic
mechanisms for anti cancer effects:
antiox/pro oxidant activities, modulate cytochrome P450 enzymes (activate carcinogens), inhibit COX2 and iNOS involved with inflamm, anti-estrogenic
which class of flavonoids have anti-estrogenic activity?
isoflavones
effects of flavonoids on cardiovascular disease:
diminished susceptibility of LDL to lipid peroxidation, inhibit platelet aggregation/NO/TNF-a (anti-thrombogenic), vasodilatory effects to decrease BP
chlorogenic acid - _____ group = caffeic acid
glycoside
examples of phenolic acids:
chlorogenic, caffeic, vannilic, gallic
salicylic acid is precursor to ____
acetylsalicylic acid (ASA)
coumarin has ____ effects
anticoagulant
salicylic acid found in:
peppermint, licorice, wheat
gallic acid found in:
tea, mango, strawberries, soy, rhubarb
examples of hydroxycinnamic acids:
caffeic acid, chlorogenic acid, cinnamic acid, ferulic acid, coumarin
major metabolite of catechins and anthocyanins that has antiox and anti-inflamm activities
protocatechuic acid
gut bacteria can break down ___ to ___
flavonoids; phenolic acids
phenolic acids are more ___ than flavonoids because ____
water soluble; have carboxylic group which is hydrophilic and just have small ring
phenolic acids have action towards enzymes involved in metabolism of ___ and __
dopamine; catecholamines
enzymatic browning is catalyzed by _____ and inhibited by____
polyphenol oxidase; ascorbic acid, acidic pH, blanching, chilling, sugar dip, sulfites
main flavonoids in green and black tea are:
catechins, theaflavins, thearubigens
green or black tea better absorbed?
green cuz best source of monomers
why teas good prevent CVD ?
v LDL oxidation, v chol lvls, v BP
why teas good prevent cancer?
free radical scavenging, anti-inflamm, ^ carcinogen detox
moderate alcohol consumption has protective effect against CVD by ^ ___ and inhibiting ___
HDL; platelet aggregation
red or white wine more polyphenols?
red usually, cuz made with skin and seeds present
polyphenols in wine?
anthocyanins, resveratrol, proanthocyanin
seeds have ___ and skins have ____
catechins; resveratrol and anthocyanins
anthocyanins found in aged wine:
pyroanthocyanins (vitisins, portisins)
wine effects;
v lipid peroxidation, ^ plasma antiox capacity, vasodilation (NO synth), anti-thrombotic (inhibit COX1)
resveratrol is weak ___ and most potent polyphenol activator of _____ which promotes cell survival and extends lifespan
antioxidant; sirtuin deacetylases
resveratrol has anti-inflamm activity by inhibiting ____ and ____ involved in production of prostaglandins
COX1 ; COX2
beer contains this kind of soluble fibre:
beta glucans
hops has __ and __
humulone ; lupulone
what does hops do:
bitter, antibacterial, stim appetite, sedative/soporific, anti-inflamm, anti-angiogenic
cocoa and chocolate have high amounts of ___ and ___ polymers
catechin; epicatechin
cocoa flavonoid benefit on cardio health:
v lipid oxidation, v platelet aggregation (^ prostacyclin and v leukotrienes)
main polyphenols in olive and sesame oils:
tyrosol, sesaminol
hydroxytyrosol and oleuropein have a ____ structure which as anti-ox activity (olive oil)
ortho-diphenolic
in rats, lignans sesaminol and sesamolin lowered amounts of ____ (marker of oxidative DNA damage)
8-OHdG
plant isoflavones and lignans considered to be ___
phytoestrogens (bind to estrogen receptors)
__ contain lots of glycosides and isoflavones (genistein and daidzein)
soybeans
mechanism for why soy proposed reduce breast cancer by altering endogenous sex-hormones and menstrual cycle
isoflavones stim sex hormone binding proteins, lower free sex hormone concentration–>longer menstrual cycle–>protect against cancer
genistein in soy induces ___ and inhibits ____, may act as ____ receptor antagonist (inhibit platelet aggregation)
tumour cell differentiation; angiogenesis; TxA2
most abundant food source of lignans
flaxseed
lignans undergo metabolic transformation by ____, resulting in formation of ____
gut microbiota; hormone-like compounds
lignans protect against ___ through formation of enterolactone and also by _____
colon cancer; fermentation and formation of butyrate
why is mangosteen not commonly imported?
fear of Asian fruit fly infestation
several bio effects of mangosteen:
anticancer, antiinflamm, antibacterial, antiox
mangosteen juice called:
xango
tomatoes red cuz of ___
lycopene
polyphenols increase ___, not necessarily lifespan
healthspan
trends for future investigations of polyphenols:
bioavailability, metabolism, distribution, diff in effects/potencies, long term effects of chronic exposure
a product isolated or purified from foods that is generally sold in medicinal forms not usually associated with food and shown to have physio benefit or provide protection against chronic disease
nutraceutical
what is a functional food?
similar in appearance to (or is) a conventional food consumed as part of usual diet, demonstrated to have physio benefit and / or reduce risk of chronic disease beyond basic nutr fxn