Department of Microbiology, School of Life Sciences, Central University of Rajasthan Bandarsindri, Kishangarh, Ajmer 305801, Rajasthan, India.
Centre for Energy and Environment, Malaviya National Institute of Technology, Jaipur 302017, Rajasthan, India.
Int J Biol Macromol. 2017 Nov;104(Pt B):1641-1647. doi: 10.1016/j.ijbiomac.2017.04.100. Epub 2017 May 6.
A novel thermophilic chitinase producing strain Humicola grisea ITCC 10,360.16 was isolated from soil of semi-arid desert region of Rajasthan. Maximum enzyme production (116±3.45Ul) was achieved in submerged fermentation. Nutritional requirement for maximum production of chitinase under submerged condition was optimized using response surface methodology. Among the eight nutritional elements studied, chitin, colloidal chitin, KCl and yeast-extract were identified as the most critical variables for chitinase production by Plackett-Burman design first. Further optimization of these variables was done by four-factor central composite design. The model came out to be significant and statistical analysis of results showed that an appropriate ratio of chitin and colloidal chitin had resulted into enhancement in enzyme production levels. Optimum concentration of the variables for enhanced chitinase production were 7.49, 4.91, 0.19 and 5.50 (gl) for chitin, colloidal chitin, KCl and yeast extract, respectively. 1.43 fold enhancement in chitinase titres was attained in shake flasks, when the variables were used at their optimum levels. Thin layer chromatography revealed that enzyme can effectively hydrolyze colloidal chitin to produce chitooligosaccharides. Chitinase production from H. grisea and optimization of economic production medium heighten the employment of enzyme for large scale production of bioactive chitooligosaccharides.
从拉贾斯坦邦半干旱沙漠地区的土壤中分离出了一株产新型嗜热壳聚糖酶的真菌灰绿曲霉 ITCC 10360.16。在液体深层发酵中实现了最大酶产量（116±3.45Ul）。使用响应面法优化了液体条件下壳聚糖酶最大产量的营养需求。在所研究的 8 种营养元素中，壳聚糖、胶体壳聚糖、KCl 和酵母提取物首先通过 Plackett-Burman 设计被确定为壳聚糖酶生产的最关键变量。通过四因素中心复合设计进一步优化了这些变量。该模型是显著的，结果的统计分析表明，壳聚糖和胶体壳聚糖的适当比例导致了酶产量水平的提高。增强壳聚糖酶生产的变量的最佳浓度分别为壳聚糖、胶体壳聚糖、KCl 和酵母提取物 7.49、4.91、0.19 和 5.50（gl）。当变量在最佳水平使用时，摇瓶中壳聚糖酶的产量提高了 1.43 倍。薄层层析表明，该酶能有效地水解胶体壳聚糖生成壳寡糖。灰绿曲霉的壳聚糖酶生产和经济生产培养基的优化提高了酶在大规模生产生物活性壳寡糖中的应用。
