The
Phytochemical Glossary
Here
is a list of terms used in phytochemical research.
-
A - Acorn
squash: Carotenoids.
Alfalfa
sprouts: In one study, their antioxidant activity
against two specific free radicals was shown to be relatively
high (46).
Almonds: One of the richest sources of alpha-tocopherol
vitamin E. Phytosterols; high in monounsaturated fats; dietary
fiber (with skin).
Apples: Quercetin and kaempferol (flavonols); dietary fiber
(including peel).
Apricots: Beta carotene. Dried are an especially rich source.
Artichokes: Silymarin (flavonoid), modest carotenoids, vitamin
C.
Asparagus: Modest source of the carotenoids lutein, zeaxanthin
and beta carotene; glutathione; folic acid. Modest source
of alpha-tocopherol vitamin E.
Avocados: High in monunsaturated fat, modest source of alpha-tocopherol
vitamin E.
>> Back
to Top -
B -
Bananas: Fiber. One South American study of vegetables,
fruits and colon cancer risk showed bananas to be the most protective
(47).
Beans: Flavonoids, dietary fiber, saponins, protease inhibitors.
Beets: In one study, their antioxidant activity against two specific
free radicals was shown to be moderately high (46).
Beet greens: The carotenoids beta carotene, lutein and xeazanthin.
Bell
peppers: Good source of plant phenols, especially coumarins,
and terpenes. Also contain glucarates, vitamin C. Reds are a moderately
good source of flavonoids and some carotenoids, especially lutein
and zeaxanthin. In one study, reds also showed moderately high
antioxidant activity against one kind of free radical (46).
Berries: Quercetin and kaempferol (flavonols), some carotenoids.
Blackberries: Fair amount of ellagic acid (although its bioavailability
is questionable).
Blueberries: Caffeic and ferulic acid (phenolic acids).
Bok
choy: A cruciferous vegetable. Rich in dithiolthiones, isothiocyanates,
flavonoids and organosulfides. It also contains glucarates, terpenes
and phenolic compounds such as coumarins.
Brazil
nuts: Vitamin E, selenium.
Broccoli: A cruciferous vegetable. Organosulfides, flavonoids,
indoles, dithiolthiones, isothiocyanates, carotenoids (highest
concentration in the leaves, more in the florets than the stems),
quercetin and keampferol (flavonols), glucarates, terpenes, phenolic
compounds such as coumarins, protease inhibitors, vitamin C, dietary
fiber and selenium. Modest source of alpha tocopherol vitamin E.
Cooking may increase the accessibility of the carotenoids and indoles.
In one study, its antioxidant activity against two specific free
radicals was fairly high (46). Calcium from broccoli is better
absorbed than from milk (48).
Brussels
sprouts: A cruciferous vegetable. Rich in organosulfides,
dithiolthiones, isothiocyanates, flavonoids, protease inhibitors
and vitamin C. Modest source of the carotenoids lutein and zeaxanthin.
They also contain glucarates, coumarins and other phenolic acids,
and terpenes. In one study, their antioxidant activity against
two specific free radicals was high (46).
>> Back
to Top -
C -
Cabbage: A cruciferous vegetable. Indoles, dithiolthiones,
isothiocyanates, flavonoids, organosulfides, glucarates, coumarins
and other phenolic acids, terpenes, selenium and vitamin C. Chinese
(Napa) cabbage is relatively high in absorbable calcium.
Canola
oil: Monounsaturated fats, vitamin E. A non-fish source
of essential fatty acids, from which omega-3s are derived.
Cantaloupe: Beta carotene, vitamin C.
Caraway: Monoterpenes in seeds and oil.
Carrots: Carotenoids (major dietary contributor of both alpha
carotene and beta carotene), plant phenols (especially flavonoids),
terpenes.
Cashew
nuts: Phytosterols.
Cauliflower: A cruciferous vegetable. Rich in indoles, dithiolthiones,
isothiocyanates, flavonoids and organosulfides. It also contains
glucarates, coumarins and other phenolic compounds, terpenes and
vitamin C.
Celery: Phenolic compounds (especially flavonoids and coumarins),
terpenes. Also the carotenoids lutein and zeaxanthin.
Cereal
grains: Many phenolic compounds (especially flavonoids
and coumarins), glucarates, carotenoids and terpenes. Corn, wheat,
oats, rice and barley are moderately good sources of phytic acid.
Wheat germ oil is one of the richest sources of vitamin E.
Cherries: Quercetin and kaempferol (flavonols), perillyl alcohol.
Chile
peppers: Modest source of carotenoids, especially lutein
and zeaxanthin, some beta carotene. Vitamin C.
Chives: Organosulfides, modest source of the carotenoids lutein
and zeaxanthin. Richer source: dried or dehydrated.
Citrus
fruits: Contain flavonoids (sometimes referred to as bioflavonoids,
an older research term), limonene and perillyl alcohol, glucarates,
carotenoids, coumarins and teriterpenes, vitamin C.
Cloves: Contain vanillin, a phenolic acid.
Collard
greens: A cruciferous vegetable. The carotenoids lutein
and zeaxanthin. Also beta carotene. In one study, eating a lot
of collard greens or spinach was associated with reduced risk of
the leading cause of blindness over 65 (23). Also, dithiolthiones,
isothiocyanates, flavonoids, organosulfides, glucarates, coumarins
and other phenolic compounds and terpenes.
Corn: Phytosterols, protease inhibitors, modest source of the
carotenoids lutein and zeaxanthin.
Cottonseed
oil: Vitamin E, about equally divided between alpha-
and gamma-tocopherol.
Cranberries: Ellagic acid (though it’s not readily absorbed),
rich source of other flavonoids.
Cruciferous vegetables: These include bok choy, broccoli, brussels
sprouts, cabbage, cauliflower, collard greens, kale, kohlrabi,
mustard greens, rutabaga, turnips, watercress. All are rich in
isothiocyanates, flavonoids and organosulfides. They also contain
glucarates, coumarins and other phenolic compounds, and terpenes.
In one study, many members of the family showed high antioxidant
activity against two specific free radicals (46).
Cucumbers: Protease inhibitors, phenolic compounds.
>> Back
to Top
-
D -
Dill: Monoterpenes, moderate carotenoids.
>> Back
to Top
-
E -
Eggplant: Good source of phenolic compounds (especially flavonoids and coumarins)
and monoterpenes. Also glucarates and teriterpenes.
Endive: Flavonoids, also the carotenoids lutein and zeaxanthin,
plus beta carotene.
Escarole: The carotenoids lutein and zeaxanthin, plus beta carotene.
>> Back
to Top
-
F -
Fennel
bulb: Moderate beta carotene.
Fenugreek: Coumarins (phenolic compounds).
Flax
seed: Extremely rich source of lignans. Also flavonoids,
coumarins and other phenolic compounds. The oil is a non-fish source
of essential fatty acids, from which omega-3s are derived.
>> Back
to Top
-
G -
Garlic: Organosulfides (notably diallyl sulfide and
allyl methyl trisulfide), which may be destroyed by heat. Also
phenolic acids, monoterpenes. Garlic shows strong antibacterial
activity. In one study, it had the highest antioxidant activity
by weight against one kind of free radical (46).
Grapefruit: Along with other citrus fruits, contains the most
biologically active of the flavonoids, as well as the monoterpene
limonene. Also vitamin C, glucarates, carotenoids, coumarins and
other phenolic compounds. Pink grapefruit is moderately high in
lycopene.
Grapes: Flavonoids, also caffeic, ferulic and ellagic acids (phenolic
acids), and resveratrol, a phenolic fungicide. Ellagic acid may
not be absorbed.
Guava: Lycopene.
>> Back
to Top
-
H -
Hazelnuts: Rich in monounsaturated fat; vitamin E.
>> Back
to Top
-
K -
Kale: A cruciferous vegetable. Extremely rich in
the carotenoids lutein and zeaxanthin, less beta carotene. A good
source of quercetin and kaempferol (flavonols). Rich in dithiolthiones,
isothiocyanates, other flavonoids and organosulfides. It also contains
glucarates, coumarins and other phenolic compounds, terpenes and
vitamin C. In one study of 22 vegetables and green and black tea,
the antioxidant activity of kale against two specific free radicals
was among the highest (46). Calcium from kale better absorbed than
from milk (48).
Kiwi: Vitamin C.
Kohlrabi: A cruciferous vegetable. Rich in dithiolthiones, isothiocyanates,
flavonoids and organosulfides. It also contains glucarates, coumarins
and other phenolic compounds, and terpenes.
>> Back
to Top
-
L -
Leeks: Organosulfides, some carotenoids.
Legumes: A lesser source of isoflavones, rich in dietary fiber.
Lemons: Along with other citrus fruits, contain the most biologically
active of the flavonoids, as well as the monoterpenes limonene
and perillyl alcohol. Also vitamin C, glucarates, coumarins and
other phenolic compounds, and teriterpenes.
Lentils: Selenium, fiber, protease inhibitors, folic acid.
Lettuce: A moderately good source of flavonoids.
Licorice
root: Phenolic compounds, especially flavonoids.
Lima
beans: Rich in phytic acid.
Limes: Along with other citrus fruits, contain the most biologically
active of the flavonoids, as well as the monoterpenes limonene
and perillyl alcohol. Also vitamin C, glucarates, coumarins and
other phenolic compounds, and teriterpenes.
>> Back
to Top
-
M -
Macadamia
nuts: In one small study, macadamia nuts neither raised nor lowered
total cholesterol, but did improve the LDL:HDL ratio (49).
Mango: Beta carotene and cryptoxanthin (another carotenoid), vitamins
C and E.
Mustard: Curcumin (phenolic compound).
Mustard
greens: A cruciferous vegetable. Rich in dithiolthiones,
isothiocyanates, the carotenoids lutein and zeaxanthin, some beta
carotene, flavonoids and organosulfides. They also contain glucarates,
coumarins and other phenolic acids, terpenes and vitamin C. Its
calcium is absorbed more efficiently than the calcium in milk (48).
Mustard
oils: Contain compounds that break down into indoles and
isothiocyanates during processing, cooking and chewing (5).
>> Back
to Top
-
N -
Nectarine: The carotenoid cryptoxanthin.
Nuts: Phytosterols, vitamin E, unsaturated fats.
>> Back
to Top
-
O -
Oats: Caffeic and ferulic acids, dietary fiber, phytic
acid.
Okra: A good source of the carotenoids lutein and zeaxanthin;
folic acid.
Olive
oil: High in monounsaturated fats; vitamin E as alpha-tocopherol,
some carotenoids.
Onions: Quercetin and kaempferol (flavonols), organosulfides,
glutathione. But white onions contain almost no quercetin.
Oranges: Along with other citrus fruits, contain the most biologically
active of the flavonoids, as well as the monoterpenes limonene
and perillyl alcohol. Also vitamin C, glucarates, mixed carotenoids,
coumarins and other phenolic compounds and teriterpenes. Canned
Mandarin oranges are especially rich in the carotenoid cryptoxanthin.
Orange
peel: The oil is the most abundant source of limonene.
Orange oil is 90% to 95% limonene by weight.
>> Back
to Top
-
P -
Papaya: Excellent source of the carotenoid cryptoxanthin and vitamin C.
Parsley: Flavones, rich in the carotenoids lutein and zeaxanthin,
also beta carotene.
Parsnips: Phenolic compounds (especially flavonoids). Also carotenoids
and terpenes.
Peaches,
dried: Beta carotene and cryptoxanthin (another carotenoid).
Peaches are modest vitamin E source, as alpha-tocopherol.
Peanuts: Phytosterols, resveratrol.
Peas: Modest source of carotenoids; dietary fiber.
Pecans: Vitamin E.
Pistachio
nuts: Rich in monounsaturated fat.
Potatoes: Vitamin C, the flavone aglycones (a plant phenol), glutathione.
One study found the antioxidant activity of potatoes nearly comparable
to broccoli (50). Potato peel contains quercetin, chlorogenic acid
and protease inhibitors, as well as dietary fiber.
Prunes: Caffeic and ferulic acids, fiber.
Pumpkin: Beta carotene, alpha carotene and other carotenoids,
phenolic compounds.
>> Back
to Top
-
R -
Radishes: Protease inhibitors, flavonoids.
Romaine
lettuce: A fair source of lutein and zeaxanthin, modest
beta carotene.
Rosemary: Rosemary extract used in studies shows strong antioxidant
properties, some of which may come from carnosol (51).
Rutabagas: A cruciferous vegetable. Rich in dithiolthiones, isothiocyanates,
flavonoids and organosulfides. They also contain glucarates, coumarins
and other phenolic compounds, and terpenes.
>> Back
to Top
-
S -
Safflower
oil: Vitamin E (predominantly alpha-tocopherol
with some gamma), phytosterols.
Sage: Monoterpenes.
Sesame
seeds: Rich in phytosterols. Richest source of phytic acid.
Shallots: Organosulfides.
Soybeans
(and soyfoods): Genistein and daidzein (isoflavonoids);
particularly rich in saponins; other plant phenols such as flavonoids,
courmarins, and caffeic and ferulic acid; lignans, carotenoids;
terpenes; protease inhibitors; phytosterols; phytic acid (inositol
hexaphosphate); dietary fiber. The oil is a non-fish source of
essential fatty acids, from which omega-3s are derived. One of
the richest sources in the American diet of gamma-tocopherol vitamin
E because so many margarines, salad dressings and packaged baked
goods rely on soybean oil. Soyfoods include soy milk, tofu and
tempeh. Soy milk is made from pureed soybeans and water. Tofu is
made from curdled soyfmilk. Tempeh is fermented soybeans--sometimes
grains are added.
Spearmint: Monoterpenes in the oil.
Spinach: Rich source of the carotenoids lutein and zeaxanthin;
also a good beta carotene and vitamin C source. Modest source of
alpha-tocopherol vitamin E. Protease inhibitors; folic acid. In
one study, eating a lot of spinach or collard greens was associated
with reduced risk of the leading cause of blindness over 65 (23).
Squash: Phenolic compounds. Winter squash is relatively high in
beta carotene. Yellow squash and spaghetti squash are modest carotenoid
sources.
Strawberries: Ellagic acid (which isn’t well absorbed), moderately
good source of the flavonols quercetin and kaempferol, vitamin
C.
String
beans: Modest source of the carotenoids lutein, zeaxanthin
and beta carotene.
Sunflower
seeds: Phytosterols. Very high in vitamin E (the oil,
too); the predominant form is alpha-tocopherol but also substantial
gamma-tocopherol.
Sweet
potatoes: Beta carotene, some vitamin E.
Swiss
chard: Rich in the carotenoids lutein and zeaxanthin, a
good source of beta carotene.
>> Back
to Top
- T
-
Tangerines: Flavonoids, coumarins and the carotenoid
cryptoxanthin.
Tea: Green tea is a good source of phenolic compounds, including
the flavonols quercetin and kaempferol. One flavonoid, catechins,
accounts for up to 30% of the dry weight of green tea; after processing,
little remains in black tea. Also glucarates, coumarins. In one
study, the antioxidant activity of both black and green teas was
higher against two specific free radicals than the activity of
22 vegetables. But they both showed pro-oxidant activity in the
presence of copper(46).
Thyme: Rich in flavones.
Tomatoes: Rich source, along with tomato products, of the carotenoid
lycopene, which gives tomatoes their red color. It is best absorbed
from processed products, such as tomato sauce or paste, that are
combined with a little oil. Vitamin C. Moderately good source of
phenolic compounds (especially flavonoids), terpenes.
Turmeric: The yellow-colored spice contains curcumin (phenolic
compound).
Turnips: A cruciferous vegetable. Rich in dithiolthiones, isothiocyanates,
flavonoids and organosulfides. They also contain glucarates,
coumarins and other phenolic compounds, and terpenes.
Turnip
greens: Isothiocyanates and indoles. Rich source of the
carotenoids lutein and zeaxanthin, plus beta carotene. The calcium
in turnip greens is absorbed more effectively than from milk (48).
>> Back
to Top
-
V-
Vanilla
bean: Vanillin, a phenolic acid.
>> Back
to Top
-
W -
Walnuts: Non-fish source of essential fatty acids, from which omega-3s
are derived. Ellagic acid (not readily absorbed); vitamin E,
phytosterols.
Watercress: A cruciferous vegetable. Rich in the carotenoids lutein
and zeaxanthin. Also beta carotene, dithiolthiones, isothiocyanates,
flavonoids and organosulfides. They also contain glucarates, coumarins
and other phenolic compounds, and terpenes.
Watermelon: Lycopene, phenolic compounds.
Wheat: Phytic acid, dietary fiber, phytosterols.
Wheat
germ: Vitamin E. Wheat germ oil is one of the richest sources
of vitamin E. Also phytosterols.
Wild
rice: Phytic acid.
Wine: Flavonoids, tannins (phenolic acids). Red wine is a good
source of the flavonols quercetin and kaempferol.
>>
Back to Top
Primary
sources: Steinmetz and Potter, "Vegetables, fruit,
and cancer prevention: A review," Journal of the American
Dietetic Association 1996; Dwyer, "Is There a Need to Change
the American Diet?" presentation, "Dietary Phytochemicals
in Cancer Prevention and Treatment," 1996; U.S. Department
of Agriculture-National Cancer Institute Carotenoid Food Composition
Data Base: Version I, 1993; Pennington: Bowes & Church’s
Food Values of Portions Commonly Used, 16th edition. For other
sources, see Bibliography.
|
