Medicinal uses and chemistry of flavonoid contents of some common edible tropical plants

Flavonoids are wide range of phytochemical with various pharmacological effects including antioxidant, anti-inflammation, anti-platelet, anti-allergic, cytotoxicity, reduce risk for heart disease or cancer etc. These flavonoids inhibited various enzymes such as prostaglandin synthase, lypoxygenase, cyclooxygenase, and induced detoxifying enzyme systems such as glutathione S-transferase. Flavonoids have significant vitamin C sparing activity and powerful antioxidants than the traditional vitamins such as quercetin, myricetin, rutin and apigenin. In vegetables, quercetin glycosides predominate, but glycosides of kaempferol, luteolin, and apigenin are also present. Fruits exclusively contain quercetin glycosides, whereas kaempferol and myricetin glycosides are found only in trace quantities. In this article we mainly discussed on three major flavonols (kaempferol, quercetin, and myricetin) and two major flavones (luteolin and apigenin) of edible tropical plants.