丝绸废水中丝胶提取方法的研究

丝绸废水经过真空浓缩和喷雾干燥制成粗粉末。采用酸析法和低温乙醇沉淀法对粗粉末中的丝胶进行提取,结果表明:低温乙醇沉淀法的提取率较高,采用体积分数为75%的乙醇溶液提取率达到64%。理化性质分析结果表明,低温乙醇沉淀法提取的丝胶蛋白含量高达90%以上,溶解度有所下降,灰分含量降低,蚕腥味被去除。应用圆二色光谱和红外光谱研究2种方法提取的丝胶二级结构分子构象的变化,结果显示提取得到的丝胶蛋白分子构象以无规卷曲为主,β转角构象的比例增加。研究结果表明,低温乙醇沉淀法是一种简便有效提取丝胶的方法。

Study on the Extraction Method for Sericin from Silk Wastewater

Silk manufacturing wastewater was concentrated under vacuum and spray—dried to crude pow- der.Then,acid precipitation method and chilled alcohol precipitation method were applied to extract sericin. The experimental results showed that the extraction yield of sericin by chilled alcohol precipitation was high- er than acid precipitation,and the yield reached 64% after using 75% ethanol.The analysis result of physi- cochemical properties of sericin suggested that the main composition was protein with a concentration above 90%,and when using 75% chilled alcohol to extract sericin,the solubility was decreased,ash content,and the bad smell from the silk was removed.The conformation of sericin was studied by circular dichroism and infrared spectrum analysis.The results suggested that the major conformation of sericin was random coil, and was changed by increasing the percentage ofβturn.The present study implied that chilled alcohol precipi- tation method was easy to operate as well as efficient.