Isolation and identification of antioxidant and hyaluronidase inhibitory compounds from Ficus microcarpa L. fil. bark.

The aerial roots and bark of Ficus microcarpa L. fil. have been used as folk herbs for perspiration, alleviating fever, and relieving pain in Okinawa. The methanol extract of its bark showed high antioxidant and potential inhibitory activity against hyaluronidase. It was fractionated into hexane, ethyl acetate, butanol, and water fractions. As the ethyl acetate fraction exhibited the strongest activity, it was selected for further purification by repeated Sephadex LH-20 column chromatography and preparative HPLC. Seven compounds were isolated and identified as protocatechuic acid, chlorogenic acid, methyl chlorogenate, catechin, epicatechin, procyanidin B1, and procyanidin B3 by analysis of ESI-MS, UV, and (1)H- and (13)C-NMR spectra. All isolated compounds showed strong antioxidant activity when tested by all applied methods. Catechin, epicatechin, procyanidin B1, and procyanidin B3 exhibited excellent inhibitory activity against hyaluronidase. The results indicate that the extract of F. microcarpa bark may be utilized as a potential antioxidant and hyaluronidase inhibitor.