Phytochemicals, also known as phytonutrients, are natural non-essential chemical compounds found in plants (phyto is a Greek word meaning “plant”). They can occur in vegetables, grains, legumes, beans, fruits, herbs, nuts, roots, leaves and seeds.
Phytochemicals are compounds that give plants their color, flavor, and smell. These compounds are thought to be largely responsible for the medicinal properties and health benefits of medicinal herbs. In addition, phytochemicals also include poisonous and toxic chemicals found in plants.
These natural compounds are classified according to their chemical structure and to some extent functional properties. There are thousands of known phytochemicals and more are discovered every year.
The list below is by no means exhaustive but does include the most common and well-known phytochemicals.
Carotenes (Orange pigments)
- α-Carotene – Yellow-orange vegetables such as carrots, sweet potatoes, pumpkin and winter squash. Also found in dark-green vegetables such as broccoli, green peas, spinach, leaf lettuce, avocado and parsley.
- β-Carotene – A pigment found in many plants and fruits (red-orange color).
- γ-Carotene – Various plants.
- δ-CaroteneLycopene – Various plants.
- Neurosporene -Many fruits and vegetables.
- Phytofluene – Found in numerous vegetables such as tomatoes.
- Phytoene – Majority of fruits and vegetables.
Xanthophylls (Yellow pigments)
- Canthaxanthin – A pigment widely distributed in in the Plant Kingdom.
- Cryptoxanthin A pigment found in the petals and flowers of plants belonging to the genus Physalis.
- Zeaxanthin – Mostly found in the leaves of nearly every green plant.
- Lutein – Found in high quantities in plants belonging to the Genus Nasturtium, in herbs like dandelion (leaves), in vegetables such as spinach and kale and in yellow carrots and turnips.
- Rubixanthin – Rose hip (Rosa spp.).
[“Spp.” is the abbreviation for “species.” and refers to all species in that given genus.]
- Saponins – Found in the plant families Caryophyllaceae, Sapindaceae, Aceraceae, Hippocastanaceae, Cucurbitaceae.
- Oleanolic acid – Olive oil (Olea europaea), American pokeweed (Phytolacca americana), woods’ rose (Rosa woodsii), honey mesquite (Prosopis glandulosa), trumpet satinash (Syzygium claviflorum), false ironwort (Hyptis capitata), marvel of Peru (Mirabilis jalapa), etc.
- Betulinic acid – White birch (Betula pubescens), Indian jujube (Ziziphus mauritiana), self heal (Prunella vulgaris), rosemary (Rosmarinus officinalis), Chinese anemone root (Pulsatilla chinensis).
- Moronic acid – Macassar kernels (Brucea javanica), mistletoe (Phoradendron reichenbachianum).
- Limonene – Plants (mainly the fruits) in the genus Citrus of the rue family (Rutaceae).
- Perillyl alcohol – Phytochemicals found in the essential oils of plants like lavender, lemongrass, sage, peppermint, etc.
- Phytosterols – Found in the cell membranes of plants. The richest sources are vegetable oils.
- Campesterol – Banana, pomegranate, pepper, coffee, grapefruit, cucumber, dandelion (Taraxacum officinale), onion, oat, potato, lemon grass (Cymbopogon citratus), rapeseed (Brassica campestris), etc.
- Beta-Sitosterol – A compound very common in the plant kingdom. It is found in vegetables, nuts, fruits and seeds.
- Stigmasterol – Soybean, calabar bean, rape seed, American ginseng (Panax quinquefolius), marvel of Peru (Mirabilis jalapa), dwarf lilyturf (Ophiopogon japonicus), etc.
- Tocopherols (Vitamin E compounds) – Olive oil, sunflower oil, soy bean, corn oil. etc.
Phenolic Compounds (Phenols)
- Apiole – Found in the essential oil of celery and all parts of parsley.
- Carnosol – Rosemary (Rosmarinus officinalis), mountain desert sage (Salvia pachyphylla).
- Carvacrol – The essential oil of oregano (Origanum vulgare), thyme (Thymus vulgaris) field pepperweed (Lepidium campestre), bee balm (Monarda fistulosa, dittany of Crete (Origanum dictamnus), marjoram (Origanum majorana), etc.
- Dillapiole – Fennel (Foeniculum Vulgare), dill (Anethum graveolens), etc.
- Rosemarinol – Found in the essential oil of many herbs in the mint family (Lamiaceae) such as rosemary.
Flavonoids (Red, blue, purple pigments)
- Quercetin – Various fruits, vegetables, leaves and grains.
- Kaempferol – Very common, found in numerous plants.
- Myricetin – Vegetables, fruits, nuts, berries, etc.
- Fisetin – Strawberries, mango, cucumber, apples, persimmons, kiwi, peaches, grapes, tomatoes, onions, catclaw acacia, quebracho tree.
- Rutin – Common rue, buckwheat, orange, grapefruit, lemon, rhubarb, cranberries, hottentot-fig.
- Isorhamnetin – Ginkgo biloba, red turnip, goldenrod, mustard leaf.
- Acacetin – Damiana (Turnera diffusa), black locust (Robinia pseudoacacia), silver birch (Betula pendula).
- Apigenin – Phytochemicals found in many plants. Common sources are parsley (Petroselinum crispum), celery (Apium graveolens), celeriac (Apium graveolens var. rapaceum), and chamomile (Matricaria recutita, Chamaemelum nobile).
- Chrysin – Purple passionflower (Passiflora incarnata), blue passionflower (Passiflora caerulea), chamomile (Matricaria recutita, Chamaemelum nobile), midnight horror (Oroxylum indicum).
- Diosmetin – Found in citrus fruits and juices, such as oranges, lemons, grapes and grapefruit. Also found in herbs like spearmint, oregano, sage, tansy and thyme.
- Tangeritin Found in tangerine and various citrus peels.
- Luteolin – Celery, broccoli, basil, green pepper, parsley, artichoke, thyme, dandelion, perilla, chamomile tea, carrots, peppermint, olive oil, rosemary, rooibos, navel oranges, and oregano.
- Anthocyanins (flavonals)
- Pelargonidin – Plant pigment found in many flowers and fruit. (orange color)
- Peonidin – Primary plant pigment (purple-red color).
- Cyanidin – Plant pigment (reddish-purple color). Found in Grapes, bilberry, red cabbage, blackberry, blueberry, cranberry, elderberry, hawthorn, loganberry, açai berry, raspberry, apples, red onion. etc.
- Delphinidin – Primary plant pigment (blue color).
- Malvidin – Primary plant pigment (blue color).
- Petunidin – Plant pigment (dark red or purple color).
- Isoflavones (phytoestrogens)
- Daidzein – Soybeans.
- Genistein – Dyer’s broom (Genista tinctoria), kudzu (Pueraria lobata), sohphlang (Flemingia vestita), flemingia (Flemingia macrophylla), etc.
- Glycitein – Soybeans.
- Pterocarpans / Coumestans (phytoestrogens) – Phytochemicals found in plants in the Fabaceae family.
- Coumestrol – Clover, alfalfa, sunflower seeds, lima and pinto beans.
- Silymarin – Milk thistle (Silybum marianum).
Lignans – Highest amounts are found in flax seed and sesame seed.
- Matairesinol – Seeds, whole grains, vegetables, and fruits.
- Pinoresinol – Found in plants in the Genus Styrax. Also present in sesame seed and in olive oil.
- Lariciresinol – Phytochemicals commonly found in plants in the Genus Brassica, ect.
- Resveratrol – White hellebore (Veratrum album), grape seed (Vitis vinifera), Japanese knotweed (Fallopia japonica), etc.
- Pterostilbene – Almonds, various berries of plants in the Genus Vaccinium, grape leaves, blueberries
- Piceatannol – Grapes, passion fruit, white tea, Japanese knotweed (Fallopia japonica).
- Pinosylvin – Present in the heartwood of plants in the Genus Pinaceae.
- Curcumin – Turmeric (Curcuma longa).
- Vanillin – Vanilla (Vanilla planifolia).
Tannins – Found in nearly all plant families.
- Punicalagins – Pomegranates (Punica granatum), Bengal almond (Terminalia catappa), East Indian almond (Terminalia myriocarpa), velvet bushwillow (Combretum molle).
- Castalagins – Oak (Quercus spp.), chestnut (Castanea spp.), African birch (Anogeissus leiocarpa).
- Vescalagins – Oak.
- Castalins – Broad-leaved paperbark (leaves) (Melaleuca quinquenervia), Oak (Quercus spp.).
- Casuarictins – Found in plants in the Genus Casuarina and Stachyurus.
- Grandinins – North American white oak (Quercus alba), European red oak (Quercus robur), broad-leaved paperbark (leaves) (Melaleuca quinquenervia).
- Punicalins – Pomegranate (Punica granatum), dooki (Combretum glutinosum), Bengal almond (Terminalia catappa).
- Roburin – Oak wood, oak cork.
- Terflavin – Yellow or chebulic myrobalan (Terminalia chebula).
- Proanthocyanidins – Maritime pine bark (Pinus pinaster, Pinus maritima), cinnamon (Cinnamomum verum), bilberry (Vaccinium myrtillus), green tea/black tea (Camellia sinensis), Irish oak (Quercus petraea), etc.
- Salicylic acid – Willow bark (Salix spp.), meadowsweet (Filipendula ulmaria).
- Vanillin – Flat-leaved vanilla (Vanilla planifolia), bicolored leptotes (Leptotes bicolor), Chinese red pine (Pinus tabuliformis).
- Vanillic acid – Dong quai (Angelica sinensis), açaí oil (Euterpe oleracea), argan oil (Argania spinosa).
- Gallic acid – Oak gall (Quercus Spp.).
- Ellagic acid – Present in many fruits and vegetables with the highest levels in blackberries, cranberries, grapes, pomegranates, raspberries, strawberries, walnuts, wolf-berries and peach.
- Tannic acid – Oak (bark, leaves) and oak gall (Quercus Spp.).
- Caffeic acid – Eucalyptus bark (Eucalyptus globulus), giant salvinia (Salvinia molesta), rosemary (Rosmarinus officinalis), caraway (Carum carvi), thyme (Thymus vulgaris), common sage (Salvia Officinalis), spearmint (Mentha spicata).
- Chlorogenic acid – Peach (Prunus persica), capillaris (Artemisia capillaris), heather (Calluna vulgaris), coffee beans, etc.
- Cinnamic acid – Cinnamon (Cinnamomum verum).
- Ferulic acid – Dong quai (Angelica sinensis), common centaury (Centaurium erythraea).
- Coumarin – Tonka bean (Dipteryx odorata), vanilla grass (Anthoxanthum odoratum), sweet woodruff (Galium odoratum), great mullein (Verbascum thapsus), sweet grass (Hierochloe odorata), cassia cinnamon (Cinnamomum cassia), deertongue (Dichanthelium clandestinum), criollo tea (Justicia pectoralis).
- Rosmarinic acid – Basil, holy basil, marjoram, rosemary, lemon balm, sage, self heal, velvetleaf soldierbush (Heliotropium foertherianum).
- Tyrosol – Olive oil, argan oil, green tea.
- Hydroxytyrosol – Olive leaf and olive oil.
- Oleocanthal – Extra-virgin olive oil.
- Oleuropein – Olive leaf.
Others Aromatic Acids
- Capsaicin – Chili pepper (Capsicum spp.).
- Gingerol – Ginger (Zingiber officinale).
- Alkylresorcinols – Phytochemicals found in wheat, rye, barley, ginkgo (Ginkgo biloba).
- Indole-3-carbinol – Found in high concentrations in vegetables such as broccoli, cabbage, cauliflower and brussels sprouts.
- 3,3′-Diindolylmethane or DIM – Broccoli, cabbage, kale, etc.
- Allicin – Garlic (Allium sativum).
- Alliin – Fresh garlic (Allium sativum).
- Allyl isothiocyanate – Mustard plant (Brassica nigra, Brassica juncea, Sinapis alba), horseradish (Armoracia rusticana), wasabi (Eutrema japonicum).
- Syn-propanethial-S-oxide – Onion (Allium cepa).
- Betanin – Beet (Beta vulgaris)
- Isobetanin – Vine spinach (Basella alba)
- Probetanin – Red and yellow pigments found in plants in the Order Caryophyllales.
- Neobetanin – Beet (Beta vulgaris), barbary fig (Opuntia ficus-indica).
- Indicaxanthin – Beet (Beta vulgaris), marvel of Peru (Mirabilis jalapa), red dragonfruit (Hylocereus costaricensis).
- Vulgaxanthin – Chard (Beta vulgaris subsp. vulgaris), beets (Beta vulgaris).
- Chlorophyllin – Green leafy vegetables such as spinach.
- Phytic acid – Seeds and grains.
- Quinic acid – Cinchona (Cinchona officinalis), coffee beans (Coffea spp.).
- Oxalic acid – Common sorrel (Rumex acetosa), etc.
- Tartaric acid – Grape (Vitis spp.), etc.
- Anacardic acid – Cashew nut (Anacardium occidentale).
- Malic acid – Fruits and vegetables, often associated with apples.
- Caftaric acid – Grapes (Vitis vinifera), common chicory (Cichorium intybus), purple coneflower (Echinacea purpurea).
- Coutaric acid – Grapes (Vitis vinifera).
- Fertaric acid – Grapes (Vitis vinifera).
- Betaine – Sugar beet (Beta vulgaris subsp. vulgaris).
- Chitin – Fungi. Found in the fungal cell wall and is not found in plants.
- Lentinan – Shiitake (Mushroom) (Lentinula edodes).
- Inulins – Phytochemicals found in common chicory (Cichorium intybus), etc.
- Lignin – Occurs in vascular plants and some algae.
- Pectins – Mostly found in non-woody parts of terrestrial plants.