The effect of several plant extracts ,including tea polyphenols ,paeonol and total fla-vonoids from Lonicera j aponica leaves (extract of ethyl acetate) ,on the activity of tyrosinase were investigated by means of spectrophotometry while vitamin C was adopted as a positive control in appropriate solvent .Results indicate that the mixture of 1% (volume ratio ) glycerol and 1% (volume ratio) Tween-80 as the solvent helps to significantly increase the solubility of paeonol and the extracts of total flavonoids from Lonicera j aponica leaves .All the tested plant extracts are able to inhibit the activity of tyrosinase to some extent ;and their inhibition capa-bility is ranked as Vc > Vc/paeonol with mass ratio of 1∶2 > Vc/paeonol with mass ratio of 1∶1 > tea polyphenol > tea polyphenol/paeonol with mass ratio of 2∶1 > paeonol > total flavonoids from Lonicera j aponica leaves .% 选择合适的溶剂体系，用维生素C（Vc）作为阳性对照物，采用分光光度法测定了不同浓度的茶多酚、丹皮酚及金银花叶子总黄酮提取物（乙酸乙酯相）对酪氨酸酶活性的抑制作用。结果表明：采用1％丙三醇和1％吐温-80（体积比1∶1）混合液作溶剂可显著增加丹皮酚和金银花叶子总黄酮提取物在水中的溶解度；茶多酚、丹皮酚、金银花叶子总黄酮提取物对酪氨酸酶的活性都有一定的抑制作用，其抑制作用从强到弱依次为Vc、Vc∶丹皮酚＝1∶2（质量比）、Vc∶丹皮酚＝1∶1（质量比）、茶多酚、茶多酚∶丹皮酚＝2∶1（质量比）、丹皮酚、金银花叶子总黄酮提取物。
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