In Vitro Antioxidant Profiles of Some Flavonoids

Baicalin ((2S, 3S, 4S, 5R, 6S)-6-(5,6-dihydroxy-4-oxo-2-phenyl-chromen-7-yl) oxy-3,4,5-trihydroxytetrahydropyran-2-carboxylic acid) and baicalein (5,6,7-trihydroxyflavone) are a flavone, a type of flavonoid. Baicalin is the glucuronide of baicalein. Phlorizin, or phloridzin is a naturally occurring flavonoid produced in some plants. It belongs to the group of dihydrochalcones. In this study, we investigated the in vitro antioxidant properties of baicalin, baicalein and phloridzin using different methods including ferric ion (Fe3+) reducing power, cupric ion (Cu2+) reducing power (CUPRAC method), reduction of Fe3+-TPTZ complex, 1,1-diphenyl-2-picrylhydrazyl free radicals (DPPH center dot) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid radicals (ABTS(center dot+)) scavenging activities. Also, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and alpha-Tocopherol were used as standard antioxidants.