NUTR 3330 FINAL EXAM WITH COMPLETE
SOLUTIONS 100% VERIFIED
Phytochemicals - ANSWER Chemicals found in plants
Generally non-nutritive substances
Physiologically active components
Polyphenols - ANSWER Most numerous and ubiquitous groups of plant metabolites
Ubiquitous in all plant organs-- integral part of diet
Range from simple phenolic molecules to highly polymerized compounds
Traditionally considered anti-nutrients
Have antioxidant capacities
Common structural feature of plant polyphenols - ANSWER Aromatic ring with at least
one hydroxyl group
Plant polyphenols synthesized via: - ANSWER 1. Shikimate Pathway
2. Acetate Pathway
T/F: Plant polyphenols contribute to the pigmentation of plants - ANSWER True
What influences the amount of polyphenols in plants? - ANSWER Light-- highest conc of
polyphenols in leaves and outer parts of plants, only trace amounts in subterranean
parts
Genetic factors
Environmental Condition s
Germination
,Variety
Processing and storage
Presence of polyphenols in food can... - ANSWER increase astringency and bitterness
T/F: Oxidation during processing/storage can affect food characteristics - ANSWER
True
Polyphenols function in food: Digestibility of Macronutrients - ANSWER Bind and
precipitate protein
Reduced absorption and increased nitrogen in the feces
Polyphenols function in food: Mineral Bioavailability - ANSWER Form complexes with
metal cations
Interfere with absorption (ie. iron and copper)
How could binding iron be a good thing? - ANSWER Iron is thought to be involved in lipid
peroxidation as well as interacts with H202; so stopping it would slow down the
formation of ROS
Type of polyphenols in food - ANSWER Phenoic Acids
Flavonoids
Flavonoids - ANSWER Labelled Vitamin P (p= pigment)
Enhance the function of vitamin C: improving absorption and protecting it from oxidation
Antioxidant effects
Subgroup of low molecular weight polyphonic substances
Ubiquitous, found in most plants
,Where are flavonoids found in most plants? - ANSWER Concentrated in seeds, fruit skins
or peel, bark, flowers
Decreased concentrations towards central core
Only trace amounts found in plants below soil surface (exceptions, garlic and onions)
Basic flavonoid structure - ANSWER A ring-- arises from acetate pathway
B ring-- arises from shikimate pathway
C ring-- determines the major class of flavonoid
What are the 6 major subclasses of flavonoids? Where do they differ? - ANSWER They
differ in terms of variations of the C-ring
1. Flavones
2. Flavonols
3. Flavanones
4. Flavanols
5. Anthocyanins
6. Isoflavones
Flavonoid Glycosides - ANSWER Typically attached/conjugated to a carbohydrate
moiety in food
Glycoside vs. Aglycone - ANSWER Glycoside-- bound to a sugar molecule
Aglycone--not bound to a sugar molecule
T/F Majority of flavonoids are glycosides - ANSWER True
Purpose of Flavonoid Glycosides - ANSWER Increases POLARITY
Necessary for storage in plant vacuoles
, Usually bound to carbohydrates-- mostly glucose
Flavonoid Bioavailability - ANSWER Flavonoids are absorbed and reach magnitudes of
concentrations in our biological fluids
Absorbed in the intestines
Flavonoid Biological Effects- Antioxidant - ANSWER Direct free radical scavengers due
to ring and hydroxyl group
Interacts with chelate metals (IRON) to prevent lipid per oxidation
Induces antioxidant-related enzymes (GST)
Protect vitamin E from oxidation; regenerates oxidized vitamin E
Flavonoid Biological Effects- Hormonal/Anti-hormonal - ANSWER Primarily estrogenic
and anti-estrogenic
Relation to hormone dependent cancers (breast, prostate)
Flavonoid Biological Effects- Anti-proliferative - ANSWER Inhibits cellular transformation
and proliferation
Inhibits growth of cancer cells (in vitro)
Interacts with enzymes associated with DNA
-- Topoisomerase iI
Flavonoid Health Effects - ANSWER Can reduce risk of several diseases/conditions
1. Cancer
2. Cardiovascular disease
3. Other (aging, diabetes)-- any condition with oxidative stress
Flavonoids and CVD - ANSWER High flavonoid intake had less than half the risk of death
from heart attack
SOLUTIONS 100% VERIFIED
Phytochemicals - ANSWER Chemicals found in plants
Generally non-nutritive substances
Physiologically active components
Polyphenols - ANSWER Most numerous and ubiquitous groups of plant metabolites
Ubiquitous in all plant organs-- integral part of diet
Range from simple phenolic molecules to highly polymerized compounds
Traditionally considered anti-nutrients
Have antioxidant capacities
Common structural feature of plant polyphenols - ANSWER Aromatic ring with at least
one hydroxyl group
Plant polyphenols synthesized via: - ANSWER 1. Shikimate Pathway
2. Acetate Pathway
T/F: Plant polyphenols contribute to the pigmentation of plants - ANSWER True
What influences the amount of polyphenols in plants? - ANSWER Light-- highest conc of
polyphenols in leaves and outer parts of plants, only trace amounts in subterranean
parts
Genetic factors
Environmental Condition s
Germination
,Variety
Processing and storage
Presence of polyphenols in food can... - ANSWER increase astringency and bitterness
T/F: Oxidation during processing/storage can affect food characteristics - ANSWER
True
Polyphenols function in food: Digestibility of Macronutrients - ANSWER Bind and
precipitate protein
Reduced absorption and increased nitrogen in the feces
Polyphenols function in food: Mineral Bioavailability - ANSWER Form complexes with
metal cations
Interfere with absorption (ie. iron and copper)
How could binding iron be a good thing? - ANSWER Iron is thought to be involved in lipid
peroxidation as well as interacts with H202; so stopping it would slow down the
formation of ROS
Type of polyphenols in food - ANSWER Phenoic Acids
Flavonoids
Flavonoids - ANSWER Labelled Vitamin P (p= pigment)
Enhance the function of vitamin C: improving absorption and protecting it from oxidation
Antioxidant effects
Subgroup of low molecular weight polyphonic substances
Ubiquitous, found in most plants
,Where are flavonoids found in most plants? - ANSWER Concentrated in seeds, fruit skins
or peel, bark, flowers
Decreased concentrations towards central core
Only trace amounts found in plants below soil surface (exceptions, garlic and onions)
Basic flavonoid structure - ANSWER A ring-- arises from acetate pathway
B ring-- arises from shikimate pathway
C ring-- determines the major class of flavonoid
What are the 6 major subclasses of flavonoids? Where do they differ? - ANSWER They
differ in terms of variations of the C-ring
1. Flavones
2. Flavonols
3. Flavanones
4. Flavanols
5. Anthocyanins
6. Isoflavones
Flavonoid Glycosides - ANSWER Typically attached/conjugated to a carbohydrate
moiety in food
Glycoside vs. Aglycone - ANSWER Glycoside-- bound to a sugar molecule
Aglycone--not bound to a sugar molecule
T/F Majority of flavonoids are glycosides - ANSWER True
Purpose of Flavonoid Glycosides - ANSWER Increases POLARITY
Necessary for storage in plant vacuoles
, Usually bound to carbohydrates-- mostly glucose
Flavonoid Bioavailability - ANSWER Flavonoids are absorbed and reach magnitudes of
concentrations in our biological fluids
Absorbed in the intestines
Flavonoid Biological Effects- Antioxidant - ANSWER Direct free radical scavengers due
to ring and hydroxyl group
Interacts with chelate metals (IRON) to prevent lipid per oxidation
Induces antioxidant-related enzymes (GST)
Protect vitamin E from oxidation; regenerates oxidized vitamin E
Flavonoid Biological Effects- Hormonal/Anti-hormonal - ANSWER Primarily estrogenic
and anti-estrogenic
Relation to hormone dependent cancers (breast, prostate)
Flavonoid Biological Effects- Anti-proliferative - ANSWER Inhibits cellular transformation
and proliferation
Inhibits growth of cancer cells (in vitro)
Interacts with enzymes associated with DNA
-- Topoisomerase iI
Flavonoid Health Effects - ANSWER Can reduce risk of several diseases/conditions
1. Cancer
2. Cardiovascular disease
3. Other (aging, diabetes)-- any condition with oxidative stress
Flavonoids and CVD - ANSWER High flavonoid intake had less than half the risk of death
from heart attack
