摘要本文是利用生物酶法辅助耦合酸法和乙醇法提取桑叶中 DNJ 的探究，通过添加特定的 酶使细胞壁结构上的纤维素、果胶等物质能够降解，减小桑叶中活性物质从细胞内向提取 介质扩散到溶液中的传质阻力，促成活性物质的溶出，提高活性物质的溶出效率，利用黑 曲霉发酵生产纤维素酶，用发酵液处理桑叶，结合酸法和乙醇法提取 DNJ,根据单因素实验 法得到酸法提取的最佳条件：选用 pH=3 的稀盐酸，最适温度为 50℃，料液比为 1:40，提 取时间为 1。5h,所得提取液经分析可知，DNJ 的提取量 1。518μg/mg。根据正交实验法得到乙 醇法提取桑叶中 DNJ 的最佳条件：pH=5 的 65％乙醇溶液、提取温度为 50℃、、提取时间 为 1h、料液比为 1:30，所得提取液经分析可知，DNJ 的提取含量为 1。1790μg/mg。用发酵 生产的纤维素酶预处理桑叶然后再耦合酸法和乙醇法提取桑叶中 DNJ，所得提取液经分析 可知，其 DNJ 提取含量分别为 1。935μg/mg、1。864μg/mg,所以经过加酶处理后细胞壁被破坏， 传质阻力减少，细胞内的活性物质充分溶出，所得提取的活性物质含量在原来的基础上进 一步的提高。82340

毕业论文关键词：DNJ；黑曲霉；纤维素酶；桑叶

Abstract This article was the use of biological enzyme extraction of mulberry leaves DNJ method combined with acid method and ethanol method, by adding a specific enzyme to the cell wall and the cytoplasm of cellulose and pectin degradation, mass transfer resistance decreases effectived component extraction from the cell to the diffusion medium, promoted the dissolution of the active ingredients to improve the extraction efficiency, the use of cellulase fermentation by Aspergillus niger, and fermentation treatment leaves, combined with acid and ethanol extraction of DNJ, according to the optimal conditions of acid extraction of the single factor experiment

method: used PH hydrochloric acid was 3, the optimum temperature was 50 ℃, the solid-liquid

ratio was 1:40, extraction time was 1。5h, the extraction liquid the analysis showed that the extraction content of DNJ was 1。518μg/mg。 According to the orthogonal experimental method to obtain ethanol extraction of DNJ from mulberry leaves, the optimum conditions: pH value to 5

65% alcohol solution, extraction temperature of 50℃, and extraction time 1h, solid-liquid ratio of

1:30, the resulting extract by analysis, we knew that, DNJ extraction content 1。1790μg/mg。 Fermentative production of cellulase treatment of mulberry leaves and then combined with acid and ethanol extraction of DNJ from mulberry leaves, the resulting extract the analysis showed that, the content of DNJ extraction respectively 1。935μg/mg 1。864μg/mg。 So after enzyme treatment of the cell wall was destroyed, the release of intracellular more DNJ, income extraction content increased。

Keywords: DNJ；Aspergillus niger；Cellulase；mulberry leaves

目 录

第 1 章 前言 1

第 2 章 文献综述 3

2。2 DNJ 的生理活性 3

2。2。1 DNJ 的降血糖作用和机理 3

2。2。3 DNJ 的抑癌作用和机理 4

2。3 DNJ 的提取方法 4

2。3。1 盐酸提取法 4

2。3。2 乙醇提取法 4

2。4 生物法产纤维素酶 4

2。4。1 纤维素酶 4

2。4。2 生产菌株