一株海洋来源蛋白酶产生菌Parengyodontium album HX2019006的鉴定及其发酵条件研究

Identification of the marine protease-producing fungus Parengyodontium album HX2019006 and the optimization of its fermentation conditions

为筛选1株产蛋白酶的海洋菌种,课题组从厦门市红树林中筛选得到1株产蛋白酶的丝状真菌,并对其细胞形态进行了扫描电镜观察,经提取其ITS序列于Genbank进行比对并构建进化树,将其鉴定为Parengyodontium album HX2019006。该菌株在海水培养基中可生产蛋白酶,通过对其培养基组分及发酵条件进行单因素优化,获得较高的蛋白酶产量后,选择培养基中麦芽糖浓度、蛋白胨浓度和培养时间3个因素进行3水平响应面优化,在优化后的培养基和发酵条件下,发酵液蛋白酶活力为71. 1 U/m L,较初始条件提高125. 7%。

A marine protease-producing fungal strain was screened from the local sea sediments in Xiamen. The morphology of this fungal strain was observed by scanning electron microscopy,and it was identified as Parengyodontium album HX2019006 by extracting the ITS sequence and comparing it in Genbank with the subsequent generation of the phylogenetic tree. This strain was capable of producing protease in seawater-based culture. We performed a single-factor optimization of the culture medium components and fermentation conditions to achieve an increase in protease yield. Three levels of maltose concentration,peptone concentration,and culture time were selected for the response surface methodology( RSM) optimization. Under the optimized culture medium and fermentation conditions,the protease activity in the fermentation broth was 71. 1 U/m L,which was 125. 7% higher than that under the initial conditions.