摘要桑叶因含有丰富的黄酮类、多酚类和多糖类等物质而具有抗氧化、抗酪氨酸 酶活性等生物活性，从而可延缓皮肤衰老、祛除或减轻色素沉着等。本实验以 20 个桑叶品种为研究对象，分别测定各品种桑叶提取液的总黄酮、总多酚以及 总多糖的含量以及测定各提取液的抑制酪氨酸酶活性，通过分析各样品抑制酪氨 酸酶活性与各活性成分间的量效关系，明确各品种桑叶的抑制酪氨酸酶活性差异 以及差异形成的原因。82336

结果表明，总黄酮、总多酚对酪氨酸酶活性的抑制起到了一个较显著的作用， 而总多糖对酪氨酸酶活性的抑制尚不明显。在 20 个品种之中，“沿河三号”和“春 陶 B”因其所含的总多酚与总黄酮含量在所有已测的桑叶品种中处于一个最高水 平，总多糖含量也处于中等，其抗酪氨酸酶活性水平是在所有桑叶中最高的。因 此开发具有抑制酪氨酸酶活性能力的桑叶产品可以选用这两个品种；“海秋处” 的酪氨酸酶抑制能力较差且总黄酮、总多酚与总多糖的含量也较低，因此“海秋 处”不适宜用于具有抗酪氨酸酶活性的桑叶产品中。该研究结果将会对日后的研 究提供了理论依据。

毕业论文关键词：酪氨酸酶；总黄酮；总多酚；总多糖；桑叶

Abstract Mulberry has antioxidant, anti-tyrosinase activity and other biological activity because of its rich flavonoids, polyphenols and polysaccharides and other substances, so it can help to delay skin aging, eliminate or reduce the pigmentation。 In this experiment, 20 mulberry varieties were used as the study objective, the content of total flavones, total polyphenol and total polysaccharides, as well as the tyrosinase activity inhibition of the various of mulberry extracting solution were respectively tested。 Through the analysis of the dose-effect relationship between the inhibit tyrosinase activity and bioactive components of samples, the inhibition of tyrosinase activity differences of various types of mulberries and reason of the differences。

The result showed that, general flavone and total polyphenols played  a significant function of rejecting the inhibit tyrosinase activity, but the rejection of the total polysaccharide is not yet clear。 Among the 20 varieties, "YanHe III" and "ChunTao B" has the largest number of total polyphenol and total flavonoid content, moderate total polysaccharides content highest anti-tyrosinase activity level of all the mulberry leaves。 Therefore, these two species can be used to develop mulberry products with the capabilities of inhibit tyrosinase activity; The ability to inhibit tyrosinase of "Hai Qiu Chu," is poor and its total flavonoids, total polyphenol and total polysaccharides content are also low, so it is not suitable for the mulberry products with the anti-tyrosinase activity。 The result will provide a theoretical basis for future studies。

Keywords: Tyrosinase; Flavonoids; Polyphenol; Polysaccharide; Mulberry leaves

目 录

第 1 章 绪论 1

1。1  概论 1

1。1。1  桑叶化学成分的研究 1

1。1。2  桑叶功能成分的药理作用 2

1。2 桑叶中的抑制酪氨酸酶活性成分 4

1。2。1  黄酮类化合物 4

1。2。2  多酚类化合物 5

1。2。3  多糖类化合物 5

1。2。4  抑制酪氨酸活性成分提取技术