kaempferoli

Kaempferol is a natural flavonol, a type of flavonoid, occurring in a wide range of plants. It is chemically known as 3,4',5,7-tetrahydroxyflavone and has the molecular formula C15H10O6 (molar mass 286.24 g/mol). In foods, kaempferol is found in high levels in onions, kale, broccoli, and other brassicas, as well as in tea, grapes, strawberries, apples, and beans. In plants, kaempferol commonly occurs as glycosides, which release the aglycone kaempferol upon hydrolysis during digestion.

Biosynthesis of kaempferol begins in the phenylpropanoid pathway from phenylalanine. Through a series of enzymes, chalcone synthase forms naringenin chalcone, which is isomerized to naringenin and then converted by flavonol synthase to kaempferol; subsequent glycosylation yields various kaempferol glycosides.

Kaempferol displays antioxidant activity and can modulate various signaling pathways. In laboratory studies, it has demonstrated anti-inflammatory, anti-oxidative, and antiproliferative effects in cells and animals; however, clinical evidence in humans is limited, and bioavailability is relatively low due to poor solubility and rapid metabolism.

In foods, kaempferol contributes to the overall health benefits associated with fruit and vegetable consumption and is used as a dietary phytochemical in nutraceutical contexts. Safety at dietary levels is generally considered acceptable, though high-dose supplementation may interact with drug-metabolizing enzymes and warrants caution in certain medical contexts.