【摘要】 以腐烂香蕉假茎中分离的皮氏罗尔斯顿菌Ralstonia sp.ZLXH-4为研究对象,对其产酶条件进行优化,鉴定该菌株的脱胶效果。通过单因素结合正交实验探讨培养基初始p H值、摇床转速、培养基葡萄糖浓度对果胶酶活性的影响,以DNS法测定果胶酶活性。在最佳产酶条件下,研究皮氏罗尔斯顿菌对香蕉假茎的脱胶效果。得到皮氏罗尔斯顿菌产果胶酶的最佳条件为p H7、摇床转速120 r/min、葡萄糖浓度15 g/L,应用于脱胶研究,香蕉假茎的残胶率为27.11%。以傅里叶红外光谱、扫描电镜和热重分析仪对脱胶产品进行了结构和热稳定性表征,表征显示纤维产品的胶质得到有效去除,热稳定性提高。结果表明,Ralstonia sp.ZLXH-4产果胶酶量较高,对香蕉假茎脱胶效果良好,对香蕉纤维的破坏较小。更多还原

【Abstract】 Ralstonia sp. ZLXH-4 was used to produce pectinase. The optimal condition was analysis and the results of bio-degumming were identified. A method of single factor binding orthogonal test was employed to analyze the influences of original p H value, shaking speed and glucose levels on the pectinase activity, which were determined using DNS method. The Ralstonia sp. ZLXH-4 was employed to accomplish degumming processing under the optimal condition. The optimal condition of pectinase production was p H7, rotary speed of 120 r/min, glucose concentration of 15 g/L. The tests of residual gum rate, FTIR, TGA and SEM results were that gum was effectively separated from the banana pseudo-stem and the residual gum rate of banana pseudo-stem fiber could be reduced to 27.11%. Furthermore, FTIR, SEM and TGA measures were used to characterize the resulting products, illustrated that heat stability of the fibers improved and the gum had been removed effectly. The Ralstonia sp. ZLXH-4 exhibited an advantage of highly producing enzyme under the optimum condition, and the strain had good effect on bio-degumming for banana pseudo-stem.更多还原