Polyphenols Flashcards Preview

NUTR 420 > Polyphenols > Flashcards

Flashcards in Polyphenols Deck (79)
Loading flashcards...
1
Q

polyphenols are widespread in ___

A

plants

2
Q

in the past, focused on polyphenols cuz ___, and now for ___

A

antinutritional effects; beneficial health effects as antioxidants

3
Q

examples of polyphenols?

A

tannins (antioxidant), ellagic acid (anticarcinogen)

4
Q

common structural features of polyphenols:

A

conjugated aromatic ring with at least 2 hydroxy substituents

5
Q

classes of polyphenols:

A

flavonoids (major), phenolic acids, lignans

6
Q

example of a phenolic acid?

A

caffeic acid

7
Q

antiox activity of polyphenols influenced by:

A

1) # and position of OH groups 2) extent of conjugated double bonds 3) lipid/aqueous solubility 4) ability bind metals

8
Q

what is French paradox?

A

even though eat lots of cheese/foie gras and smoke, still low incidence of heart disease (is it because of red wine??)

9
Q

diff factors that influence diet intake of polyphenols

A

plant genes/enviro conditions, ripeness, processing/storage

10
Q

___ browning causes oxidation of polyphenols

A

enzymatic

11
Q

how to prevent enzymatic browning?

A

acid (denature enzymes causing browning) and vit c (re-reduce oxidation of polyphenols)

12
Q

absorption of polyphenols influenced by degree of ___

A

glycosylation

13
Q

glucose enhances ___ absorption, other sugars ___ absorption

A

quercetin; inhibit

14
Q

some polyphenols and condensed tannins have ____ effect in rats

A

hypercholesterolemic

15
Q

polyphenols can decrease post prandial _____ response by inhibiting enzymes

A

glycemic

16
Q

what is CBG?

A

cytosolic beta glucosidase

17
Q

what is COMT?

A

catechol-O-methyltransferase

18
Q

what is UDPGT?

A

UDP glucuronyl transferase

19
Q

what is SULT?

A

phenol sulfotransferase

20
Q

identified in 1930s by Albert

A

flavonoids

21
Q

flavonoids work together with ____ to prevent capillary permeability

A

vitamin C

22
Q

differences in flavonoids come from diffs between ____

A

c-ring (mid ring)

23
Q

diff between flavone and isoflavone?

A

presence of R group in isoflavone

24
Q

proanthocyanins similar to ____ not anthocyanins

A

catechins

25
Q

proanthocyanidins are also called:

A

condensed tannins

26
Q

__ have bitter taste, ___ have astringent taste, ___ have natural dyes

A

flavones/flavanones; flavanols; antocyanins

27
Q

how does antiox activity work?

A

ability donate H atom from aromatic hydroxyl group to free radical

28
Q

how does flavonoid be anti-inflammatory?

A

inhibit NfkB activation, inhibit enzymes

29
Q

flavonoid effect on cancer:

A

antiproliferative, pro-apoptotic, anti-inflamm, anti-angiogenic

30
Q

mechanisms for anti cancer effects:

A

antiox/pro oxidant activities, modulate cytochrome P450 enzymes (activate carcinogens), inhibit COX2 and iNOS involved with inflamm, anti-estrogenic

31
Q

which class of flavonoids have anti-estrogenic activity?

A

isoflavones

32
Q

effects of flavonoids on cardiovascular disease:

A

diminished susceptibility of LDL to lipid peroxidation, inhibit platelet aggregation/NO/TNF-a (anti-thrombogenic), vasodilatory effects to decrease BP

33
Q

chlorogenic acid - _____ group = caffeic acid

A

glycoside

34
Q

examples of phenolic acids:

A

chlorogenic, caffeic, vannilic, gallic

35
Q

salicylic acid is precursor to ____

A

acetylsalicylic acid (ASA)

36
Q

coumarin has ____ effects

A

anticoagulant

37
Q

salicylic acid found in:

A

peppermint, licorice, wheat

38
Q

gallic acid found in:

A

tea, mango, strawberries, soy, rhubarb

39
Q

examples of hydroxycinnamic acids:

A

caffeic acid, chlorogenic acid, cinnamic acid, ferulic acid, coumarin

40
Q

major metabolite of catechins and anthocyanins that has antiox and anti-inflamm activities

A

protocatechuic acid

41
Q

gut bacteria can break down ___ to ___

A

flavonoids; phenolic acids

42
Q

phenolic acids are more ___ than flavonoids because ____

A

water soluble; have carboxylic group which is hydrophilic and just have small ring

43
Q

phenolic acids have action towards enzymes involved in metabolism of ___ and __

A

dopamine; catecholamines

44
Q

enzymatic browning is catalyzed by _____ and inhibited by____

A

polyphenol oxidase; ascorbic acid, acidic pH, blanching, chilling, sugar dip, sulfites

45
Q

main flavonoids in green and black tea are:

A

catechins, theaflavins, thearubigens

46
Q

green or black tea better absorbed?

A

green cuz best source of monomers

47
Q

why teas good prevent CVD ?

A

v LDL oxidation, v chol lvls, v BP

48
Q

why teas good prevent cancer?

A

free radical scavenging, anti-inflamm, ^ carcinogen detox

49
Q

moderate alcohol consumption has protective effect against CVD by ^ ___ and inhibiting ___

A

HDL; platelet aggregation

50
Q

red or white wine more polyphenols?

A

red usually, cuz made with skin and seeds present

51
Q

polyphenols in wine?

A

anthocyanins, resveratrol, proanthocyanin

52
Q

seeds have ___ and skins have ____

A

catechins; resveratrol and anthocyanins

53
Q

anthocyanins found in aged wine:

A

pyroanthocyanins (vitisins, portisins)

54
Q

wine effects;

A

v lipid peroxidation, ^ plasma antiox capacity, vasodilation (NO synth), anti-thrombotic (inhibit COX1)

55
Q

resveratrol is weak ___ and most potent polyphenol activator of _____ which promotes cell survival and extends lifespan

A

antioxidant; sirtuin deacetylases

56
Q

resveratrol has anti-inflamm activity by inhibiting ____ and ____ involved in production of prostaglandins

A

COX1 ; COX2

57
Q

beer contains this kind of soluble fibre:

A

beta glucans

58
Q

hops has __ and __

A

humulone ; lupulone

59
Q

what does hops do:

A

bitter, antibacterial, stim appetite, sedative/soporific, anti-inflamm, anti-angiogenic

60
Q

cocoa and chocolate have high amounts of ___ and ___ polymers

A

catechin; epicatechin

61
Q

cocoa flavonoid benefit on cardio health:

A

v lipid oxidation, v platelet aggregation (^ prostacyclin and v leukotrienes)

62
Q

main polyphenols in olive and sesame oils:

A

tyrosol, sesaminol

63
Q

hydroxytyrosol and oleuropein have a ____ structure which as anti-ox activity (olive oil)

A

ortho-diphenolic

64
Q

in rats, lignans sesaminol and sesamolin lowered amounts of ____ (marker of oxidative DNA damage)

A

8-OHdG

65
Q

plant isoflavones and lignans considered to be ___

A

phytoestrogens (bind to estrogen receptors)

66
Q

__ contain lots of glycosides and isoflavones (genistein and daidzein)

A

soybeans

67
Q

mechanism for why soy proposed reduce breast cancer by altering endogenous sex-hormones and menstrual cycle

A

isoflavones stim sex hormone binding proteins, lower free sex hormone concentration–>longer menstrual cycle–>protect against cancer

68
Q

genistein in soy induces ___ and inhibits ____, may act as ____ receptor antagonist (inhibit platelet aggregation)

A

tumour cell differentiation; angiogenesis; TxA2

69
Q

most abundant food source of lignans

A

flaxseed

70
Q

lignans undergo metabolic transformation by ____, resulting in formation of ____

A

gut microbiota; hormone-like compounds

71
Q

lignans protect against ___ through formation of enterolactone and also by _____

A

colon cancer; fermentation and formation of butyrate

72
Q

why is mangosteen not commonly imported?

A

fear of Asian fruit fly infestation

73
Q

several bio effects of mangosteen:

A

anticancer, antiinflamm, antibacterial, antiox

74
Q

mangosteen juice called:

A

xango

75
Q

tomatoes red cuz of ___

A

lycopene

76
Q

polyphenols increase ___, not necessarily lifespan

A

healthspan

77
Q

trends for future investigations of polyphenols:

A

bioavailability, metabolism, distribution, diff in effects/potencies, long term effects of chronic exposure

78
Q

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

A

nutraceutical

79
Q

what is a functional food?

A

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