• Korean Journal of Pharmacognosy
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• v.27 no.3
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• pp.212-218
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• 1996

Two phenolcarboxylic acids. five flavonoids and one hydrolysable tannin were isolated from the leaves of Acer ginnala Maxim. On the basis of chemical and spectroscopic evidence, the strutures of these compounds were established as gallic acid, ethylgallate, acertannin, quercetin, quercitrin, isoquercitrin, rutin, $quercetin-3-O-{\alpha}-_L-rhamnopyranosyl-2'-gallate$.

• Korean Journal of Pharmacognosy
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• v.24 no.1
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• pp.20-25
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• 1993

Three phenolcarboxylic acids, two flavonoids and four hydrolysable tannins were isolated from the whole plant of Acalypha australis. On the basis of chemical and spectroscopic evidence, the structures of these compounds were established as gallic acid, protocatechuic acid, caffeic acid, rutin, isoquercitrin, corilagin, furosin and geraniin.

• YAKHAK HOEJI
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• v.45 no.2
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• pp.214-219
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• 2001

Nineteen hydrolysable tannins isolated from the Euphorbia helioscopia (Euphorbiaceae) were tested for the inhibitory effect on mushroom tyrosinase activity in vitro. Inhibitory effect of gallotannin group exhibited more potent than that of phenolcarboxylic acid and ellagitannin groups against the enzyme activity. The inhibitory activity by pentagalloyl glucose on mushroom tyrosinase was more potent ($IC_{50}$/, 4.9 $\mu$M) than that of kojic acid ($IC_{50}$/, 8.7 $\mu$M).