• Natural Product Sciences
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• 제18권3호
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• pp.200-203
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• 2012

The chromatographic separation of a methanol extract of Prunus mume (Rosaceae) led to the isolation of 5-hydroxymethyl-2-furaldehyde (1), 4-O-caffeoylquinic acid methyl ester (2), prunasin (3), 5-O-caffeoylquinic acid methyl ester (4), benzyl-O-${\beta}$-D-glucopyranoside (5), and liquiritigenin-7-O-${\beta}$-D-glucopyranoside (6). Their structures were determined by 1D, 2D-NMR and MS data analysis as well as by comparison of their data with the published values.

• Natural Product Sciences
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• 제22권2호
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• pp.111-116
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• 2016

Phytochemical investigation of the stems of Pueraria lobata (Wild) Ohwi (Leguminosae), led to the isolation of eighteen known compounds: ${\beta}$-amyrone (1), (+)-pinoresinol (2), (+)-syringaresinol (3) $(+)-syringaresinol-O-{\beta}-{\small{D}}-glucoside$ (4), (+)-lariciresinol (5), (-)-tuberosin (6), naringenin (7), liquiritigenin (8), isoliquiritigenin (9) genistein (10), daidzein (11) daidzin (12) daidzein 4',7-diglucoside (13) 2,4,4'-trihydroxy deoxybenzoin (14), S-(+)-1-hydroxy-3-(4-hydroxyphenyl)-1-(4-hydroxy-2-methoxy-phenyl)propan-2-one (15), methyl $2-O-{\beta}-{\small{D}}-glucopyranosylbenzoate$ (16), pyromeconic acid $3-O-{\beta}-{\small{D}}-glucopyranoside$ 6'- (O-4''-hydroxy-3-methoxybenzoate) (17), and allantion (18). The chemical structures of these compounds were elucidated from spectroscopic data and by comparison of those data with previously published results. The effects of isolated compounds on mushroom tyrosinase enzymatic activity were screened. The results indicated that, chloroform extract of P. lobata stems turned out to be having tyrosinase inhibitory effect, and only compounds 5, 8, 9, and 11 showed enzyme inhibitory activity, with $IC_{50}$ values of $21.49{\pm}4.44$, $25.24{\pm}6.79$, $4.85{\pm}2.29$, and $17.50{\pm}1.29{\mu}M$, respectively, in comparison with these of positive control, kojic acid ($IC_{50}\;12.28{\pm}2.72{\mu}M$). The results suggest that P. lobata stems extract as well as its chemical components may represent as potential candidates for tyrosinase inhibitors.