化妆品基础环境对β-熊果苷稳定性的影响

Effects of basic environmental conditions of cosmetic matrix on the stability of β-arbutin

熊果苷是美白和祛斑作用的化妆品中最为广泛使用的美白剂之一。选取β-熊果苷为研究对象,改变化妆品的温度和pH值,对β-熊果苷的稳定性进行讨论。同时,采用紫外分光光度法测定β-熊果苷在不同浓度和不同基础环境下分解产物含量。实验结果表明,温度为30℃~40℃,质量分数为0.2%~1.0%时,β-熊果苷相对稳定。反应温度高于50℃时,β-熊果苷溶液的分解趋势曲线陡增,可分析50℃为β-熊果苷的极限分解温度;β-熊果苷在中性及偏酸性的pH条件下相对稳定,在酸性（pH〈4）或碱性（pH〉9）的环境下易分解。并由此进一步确定适用于美白和祛斑类化妆品的体系的温度和酸碱度。

Arbutin is the current role that was widely used as whitening agent in freckle whitening cosmetics.The paper studied the activity and stability of β-arbutin in cosmetic matrix at different temperature and various pH value,analyzed the content of its decomposition products at different concentration and different enviounmental matrix by UV spectrometer.Experimental data showed that β-arbutin is stable at the condition of temperature from 30 ℃ to 40 ℃ and concentration from 0.2% to 1.0%.The decomposition curve goes up straightly when temperature exceeds 50 ℃.Thus 50 ℃ is the maximum temperature available for β-arbutin stability.It is easy to break down in acidic（pH 4）or alkaline（pH 9） solution while maintains stable in neutral or slightly acidic matrix（4pH9）.