Table 1.

Classification of phytochemicals

Classification of phytochemicals, examples				Sources
Phenolics	Phenolic acids	Hydroxybenzoic acids	Gallic, vanillic, syringic	Chestnuts (boiled or roasted), witch hazel, tea leaves, oak bark, rhubarb, etc
		Hydroxycinnamic acids	p-Coumaric, caffeic, ferulic, sinapic	Barley, eucalyptus, coffee, Arabidopsis, Hibiscus, etc
	Flavonoids	Flavonols	Quercetin, kaempferol, myricetin	Aloe vera, European elderberry, soy, St John’s wort, tomatoes, red onions, etc
		Flavones	Apigenin, luteolin	Celery, parsley, chamomile tea, green peppers, thyme, oregano, etc
		Flavanols (catechins)	Catechin, epicatechin, epigallocatechin gallate	White tea, green tea, persimmon, pomegranate, cocoa beans, etc
		Flavanones	Eriodictyol, hesperetin	Citrus fruits, rose hip, mountain balm, etc
		Anthocyanidins	Cyanidin, pelargonidin, malvidin	Grapes, berries, red cabbage, red onions, plums, kidney beans, geranium, etc
		Isoflavonoids	Genistein, glycitein	Lupin, fava beans, soy, coffee, etc
	Stilbenes			Grapes, etc
	Coumarins			Tonka bean, vanilla grass, etc
	Tannins			Eucalyptus, geranium, etc
Carotenoids	α-carotene, β-carotene, lutein, zeaxanthin, lycopene			Carrots, broccoli, spinach, zucchini, etc
Alkaloids				Poppy, tomatoes, potatoes, etc
Organosulfur compounds	Isothiocyanates, indoles, allyl sulfur compounds			Cabbage, broccoli, spinach, garlic, onions, etc