Antioxidant activity of a new C-glycosylflavone from the leaves of Ficus microcarpa

By bioactive-guided fractionation of methanol extract of the Ficus microcarpa leaves, one new C-glucosylflavone, ficuflavoside (1), one new megastigmane glycoside, ficumegasoside (8), and twelve known compounds including flavonoids (2–6), phenylpropanoids (7), megastigmanes (9–11) and sterol derivatives (12–14) were isolated. Their chemical structures were elucidated by mass, 1D, and 2D NMR spectroscopies. The antioxidant activities of these compounds were measured using the oxygen radical absorbance capacity methods. Compounds 1–6 exhibited potent antioxidant activities of 6.6–9.5 μM Trolox equivalents at the concentration of 2.0 μM. The results indicated 2, 3, and 5 having meaningful reducing capacity of copper (I) ions concentration of 6.1–8.4 μM.

Graphical abstractBy bioactive-guided fractionation of methanol extract of the Ficus microcarpa leaves, one new C-glucosylflavone, ficuflavoside (1), one new megastigmane glycoside, ficumegasoside (8), and twelve known compounds were isolated. The antioxidant activities of these compounds were measured using the oxygen radical absorbance capacity methods. Flavonoids 1–6 exhibited potent antioxidant activity of 6.6–9.5 μM Trolox equivalents at the concentration of 2.0 μM. The results also indicated 2, 3, and 5 having meaningful reducing capacity of copper (I) ions concentration of 6.1–8.4 µM.Figure optionsDownload full-size imageDownload as PowerPoint slide