구지뽕나무 잎의 항산화 성분

Anti-oxidant Compounds of Cudrania tricuspidata Leaves

Cudrania tricuspidata Bereau (Moraceae) have been used for anti-inflammatory, anti-hepatotoxic, anti-hypertensive and anti-diabetic activities. In order to investigate the efficacy of antioxidant activity, the bio-activity guided fraction and isolation of Biologically active substance were performed. H2O, 30%, 60%, 100% MeOH and acetone fractions were examined on the antioxidant activity by DPPH method. It was shown that 30%, 60%, 100% MeOH fractions have significantly antioxidant activity. From 30% MeOH fraction, two dihydroflavonoid glycosides dihydroquercetin 7-O-β-D-glucopyranoside (I), dihydrokaempferol 7-O-β-D-glucopyranoside (V) were isolated and 60% MeOH fraction, six flavonoids including quercetin 3-O-α-L-rhamnopyranosyl(1→6)-β-D-glucopyranoside (Ⅱ), quercetin 3-O-β-D-glucopyranoside (Ⅲ), quercetin 7-O-β-D-glucopyranoside (Ⅳ), kaempferol 3-O-α-L-rhamnopyranosyl(1→6)-β-D-glucopyranoside (Ⅵ), kaempferol 3-O-β-D-glucopyranoside (Ⅶ), kaempferol 7-O-β-D-glucopyranoside (Ⅷ) were isolated. To investigate the antioxidant activities of each compounds, we measured radical scavening activity with DPPH method and anti-lipid peroxidative efficacy on low density lipoprotein (LDL) with TBARS assay. Four compounds of quercetin glycosides (Ⅰ,Ⅱ,Ⅲ,Ⅳ) showed significant antioxidant activity.