采用腊样芽孢杆菌D7对蚕丝进行精练的工艺优化

蚕丝精练过程中利用微生物脱胶具有作用温和、成本低、环境污染小的优点。采用脱胶细菌腊样芽孢杆菌(Bacillus cereus)D7对蚕丝进行微生物精练,研究了脱胶发酵温度、发酵液初始pH、菌种液接入量、菌液发酵摇床转速、脱胶发酵时间等因素对残胶率和蛋白酶活力的影响,得出利用腊样芽孢杆菌D7对蚕丝精练的最佳工艺条件为:脱胶发酵温度37℃,发酵液初始pH7.0,菌种液接入量5%,菌液发酵摇床转速150 r/min,脱胶发酵时间3 d。在此工艺条件下用D7菌液精练后的蚕丝纤维表面丝胶更少且分布更均匀,纤维断裂强度、断裂伸长率和屈服强力都优于化学精练法处理的蚕丝。

Optimization of Silk Degumming Technology Using Bacillus cereus D7

Microbiological degumming of silk has the advantages of mild action condition,low cost and less pollution to environment.In this study,Bacillus cereus strain D7 was used to degum spun silk.The influences of fermentation temperature,initial pH value of fermentation liquid,amount of inoculated bacteria,rotation speed of the shaker,and fermentation time on residual gum rate and protease activity were investigated.The optimum conditions for degumming were as follows: temperature 37 ℃,pH value 7.0,amount of inoculum 5%,rotation speed 150 r/min and incubation time 3 d.Under this technological condition,sericin on the surface of silk fiber was minimum and was more evenly distributed.Fiber breaking strength,elongation rate at breakage,and yielding strength were also better than those from chemical degumming.