耐热普鲁兰酶真菌的筛选、鉴定及酶学性质研究

本研究从西藏羊八井热泉下游淤泥中筛选得到了一株高产耐热普鲁兰酶菌株YBJ10-2,经诱导后其最高产酶量可达55.732U/mL,是目前国内外发现的产酶量较高的真菌。根据形态特征及18S rDNA序列同源性分析,初步判定菌株YBJ10-2属于球孢枝孢菌。该菌株发酵所产耐热普鲁兰酶在65-75℃和pH 5.0-8.0条件下较稳定,最适pH值为6.5,最适温度为72℃,对普鲁兰糖和支链淀粉催化能力最强,具有广阔的开发应用前景。

Isolation,Identification of a High-yield Thermostable Pullulanase Fungi and Research of the Enzyme Properties

The strain of high heat resistant pullulanase was isolated from the Tibet Yangbajain hot springs' downstream silt,named YBJ10-2.The highest enzyme production capacity up to 55.732U/mL of the induced stain,is a fungi of enzyme higher producing.Based on morphological characters and 18S rDNA sequence homology analysis,determined the strain YBJ10-2 belongs to Beauveria branch bacillus.The pullulanase at 65-75℃ and pH 5-8 conditions are relatively stable,the optimum pH value is 6.5,the optimum temperature is 72℃,on pullulan and amylopectin catalytic capability is the strongest.It has wide development and application prospect.