Phytochemicals Flashcards
Quercetin protects ascorbic acid from:
a. oxidation.
b. reduction.
c. dehydrogenation.
d. desaturation.
a. oxidation.
Flavonoids are:
a. water soluble
b. lipid miscible
c. alcohols
d. carcinogens
b. lipid miscible (can mix with lipids)
Beta-glucans are derived from:
a. mushrooms
b. garlic and onions
c. berries
d. yellow and orange produce
a. mushrooms
Beta glucans (also called mycopolysaccharides or beta-D-glucans) are soluble fibers that come from the cell walls of bacteria, fungi, yeasts, algae (seaweed) and some grains such as oats, barley, rice, rye, wheat.
https://www.webmd.com/vitamins-and-supplements/beta-glucans-uses-and-risks
Beta-d-glucans obtained from oats act as _____ dietary fiber.
a. soluble
b. insoluble
a. soluble
Soluble fiber = dissolves in water and forms a thick, gel-like substance. Like other types of soluble fiber, beta glucans slows the passage of food as it travels through your intestines; BGs are also used for lowering LDL and total cholesterol.
insoluble fiber = doesn’t dissolve; rather it absorbs liquid as it travels through the digestive tract
Allicin, an organosulfur compound found in garlic and onions, may help reduce:
a. total cholesterol and blood pressure
b. triglycerides and LDL
c. ghrelin and adiponectin
d. ferritin and CRP
a. total cholesterol and blood pressure
Crushing or chopping garlic releases an enzyme called alliinase, which converts allinin to allicin. Allicin rapidly breaks down to form a variety of organosulfur compounds (where its therapeutic properties come from). Garlic cloves (Allium sativum), a species in the Alliaceae plant family, actually produce more allicin via enzymatic reactions when the plant is attacked or injured (defense mechanism). Allicin is considered to be an “unstable” compound because it’s only present in fresh, unheated garlic that has been cut or crushed, but not cooked. The best way to get allicin is via fresh crushed/sliced garlic - heating garlic has been shown to reduce its antioxidant, antibacterial and vascular protective effects, since it changes the chemical composition of sulfur compounds.
https://draxe.com/nutrition/allicin/
All of the below are true of carotenoids EXCEPT:
a. Carotenoids are found in plants that produce bright red, orange and yellow pigments
b. Only beta-carotene, alpha-carotene, and beta-cryptoxanthin exhibit vitamin A activity
c. Terpenes are carotenoids found in green foods, soybeans and grains and function as antioxidants
d. Lutein and zeaxanthine are not considered cartoenoids
d. Lutein and zeaxanthine are oxycarotenoids found in chicken egg yolks, corn, broccoli, green beans, peas, brussel sprouts, cabbage, kale, collard greens, spinach, lettuce, kiwi fruit, honeydew melons and the petals of many flowers (zeaxanthin is the principal pigment of yellow corn). They absorb potentially damaging blue and near-ultraviolet radiation in the macula of the human retina, exhibit antioxidant and phytoestrogenic properties and may protect against photo damage of the retina, heart disease, stroke, macular degeneration and age-related cataract formation.
Carotenoids are tissue-specific in their actions, which include all of the below EXCEPT:
a. enhancement of the immune response
b. protection against ultraviolet radiation
c. aid in production of intrinsic factor, pepsin, gastric lipase
d. sparing of glutathione peroxidase and other Phase II detoxification enzymes
c. aid in production of intrinsic factor, pepsin, gastric lipase
True of false? Absorption of beta-carotene is impaired when there is steatorrhea
True - Carotenoids require emulsification and solubilization into micelles for absorption in
the intestinal mucosa.
The bioavailability of carotenoids from raw vegetables is typically low due to the food matrix (processing and cooking helps to release carotenoids from their food matrix and thus enhance absorption). Therefore, carotenoids are absorbed better with fat or when cooked, chopped or pureed.
CARTENOID CHEAT SHEET:
Alpha & beta carotene = orange/yellow (carrots, winter squash, mangoes, apricots, oranges); also spinach (chlorophyll masks the yellow-orange pigment)
Lycopene = red (tomatoes, watermelon, guava, pink grapefruit)
Lutein and zeaxanthin = dark green leafy & yellow (corn, yellow pepper); Lutein is also rich in egg yolk, zeaxanthin also rich in salmon.
Beta-cryptoxanthin = red/orange (sweet red peppers, oranges, peaches, papaya)
Terpenes = greens/soybeans/grains
The human diet contains two sources for vitamin A: preformed vitamin A (retinol and retinyl esters) and provitamin A carotenoids.
Preformed vitamin A = animal sources (dairy products, eggs, fish, and organ meats)
Provitamin A carotenoids = plant pigments that the body converts into vitamin A in the intestine. The main provitamin A carotenoids in the human diet are beta-carotene, alpha-carotene, and beta-cryptoxanthin. Other carotenoids in food, such as lycopene, lutein, and zeaxanthin, are not converted into vitamin A and are referred to as non-provitamin A carotenoids.
https://ods.od.nih.gov/factsheets/VitaminA-HealthProfessional/#:~:text=Provitamin%20A%20carotenoids%20are%20plant,beta%2Dcryptoxanthin%20%5B1%5D.
Which of the below are considered a class of flavonoids?
a. Flavones
b. Flavonols
c. Flavanones
d. Flavan-3-ols
e. Isoflavones
f. Anthocyanidins
ALL
Catechins (a type of flavan-3-ol flavonoids) are found in many plants and are found in the greatest amounts in:
a. grape seeds, green tea leaves
b. berries, cherries
c. dark leafy greens
d. root vegetables
a. grape seeds, green tea leaves
The main catechins are:
- Epicatechin (EC)
- Epigallocatechin (EGC)
- Epicatechin-3-gallate (ECG)
- Epigallocatechin-3-gallate (EGCG) – most abundant in green tea
Flavonoids have been seen to possess the below properties (select all that apply):
a. inhibit estrogen synthesis
b. strengthen capillary integrity
c. enhance the effects of vitamin C
d. retard the development of cataracts
e. suppress cortisol release
All but e
Flavonoids are potent antioxidants and have also been reported to inhibit cell adhesion, growth factor activity and cell proliferation involved in the development of atherosclerosis and cancer; and have protective actions against allergies, inflammation, free radical generation, platelet aggregation, hepatotoxicity of xenobiotics, peptic ulceration, infection with bacteria and viruses and tumorigenesis.
Quercitin is a _______ that is found in citrus fruits, apples, onions and green tea.
a. flavonol
b. flavan-3-ol
c. isoflavone
d. flavanone
a. flavonol
In general, flavonoids are found in citrus fruits, soybeans, legume vegetables, onions, wine, green teas, licorice root, flax seed and other
cruciferous, umbelliferous (i.e. anise, carrots, celery, parsley), solanaceous (nightshades) and cucurbitaceous (cucumber family - zucchini, squash (winter and summer), pumpkin, watermelon, cantaloupe) vegetables.
Glucomannan is a source of _____ fiber usually made from the root of the konjac plant. Glucomannan exhibits _____ activity and may contribute to glucose homeostasis and weight management by interfering with the absorption non-fiberous carbohydrates.
a. soluble; laxative
b. insoluble; antidiarrheal
c. soluble; antidiarrheal
b. insoluble; laxative
a. soluble; laxative
Typical adverse reactions to moderate intakes include abdominal distension and flatulence, particularly in individuals with poor intakes of dietary fiber.
Glucosinolates are found in ______ vegetables:
a. cruciferous
b. root
c. leafy green
d. marrow
e. allium
a. cruciferous - cabbage, brussels sprouts, bok choy, kohlrabi, mustard greens, rutabaga, turnips, watercress, kale
Upon chopping/chewing, glucosinolates are converted to indoles and isothiocyanates - which bind (and deactivate) chemical carcinogens and act as powerful activators of liver and gastrointestinal detoxification enzymes, regulators of cytokine secretion by leukocytes, and inhibitors of enzymes that promote tumor growth in the liver, breast, colon, stomach, lung and esophagus.
Main function = DETOXIFICATION
Interestingly, indole-3-carbinol (I3C) is a degradation product of one type of glucosinolate, called glucobrassicin (sulforaphane is another breakdown product of a different type of glucosinolate, called glucoraphanin or SGS, it and induces the expression of hepatic Phase II detoxification enzymes). I3C is produced by the action of an enzyme (myrosinase) in cruciferous veggies that is activated upon maceration. I3C is further broken down in the gut to various active metabolites (this metabolism is pH dependent, requiring the normal acid environment of the stomach). The most predominant metabolite seems to be DIM (3,3′-diindolylmethane), and it seems to be the most stable, hence the easiest to isolate in supplement form.
In terms of a dietary supplement, the benefits for I3C and DIM are similar, most likely because of the high rate at which I3C converts to DIM. However, DIM seems to be the preferred supplemental form because of the relative instability of I3C and its conversion to other molecules whose biological actions are not well studied. When you supplement with DIM, you are going straight to the active molecule without waiting for your body to first complete all of the conversion steps (similar to the difference between taking NAC vs. glutathione).
https: //edu.emersonecologics.com/2019/02/11/indole-3-carbinol-i3c-and-dim/
https: //www.thorne.com/take-5-daily/article/what-is-dim-is-it-the-same-as-i3c
