玉米秸秆低温降解菌的分离筛选及鉴定

Isolation and Identification of Low-temperature Degrading Strains for Corn Stubble

摘要: 利用从渭源县山地采集的30份样品,采用刚果红染色法和液体摇瓶发酵法筛选出了1株能够在15℃条件下降解羧甲基纤维素、玉米秸秆纤维素和高产纤维素酶的真菌菌株D5,同时测定了该菌株纤维素酶活力和对玉米秸秆的降解能力,并通过ITS rDNA序列分析对该真菌进行了初步鉴定。结果表明,菌株D5液体培养7 d的木聚糖酶活为52.7 U·mL^-1,CMCase酶活为31.5 U·mL^-1,滤纸酶活为29.6 U·mL^-1;菌株D5在玉米秸秆为唯一碳源的培养基里发酵10 d,玉米秸秆的失重率为29.8%。菌株D5经ITS rDNA序列分析初步鉴定为Penicillium sp.,在玉米秸秆降解方面具有较大的应用潜力。

Abstract: Using samples collected from hilly land of Wei Yuan county of Gansu province, a cellulose-degrading fungi strain D5 was isolated through methods of Congon red stain and liquid shake-flask fermentation at 15℃. The cellulase activity and corn stubble degrading ability of strain D5 were determined, and strain D5 was classified according to the analysis of its 18S rRNA gene sequences. The result showed that Xylanase, CMCase and filter paper activity(FPA) of strain D5 were 52.7 U·mL^-1, 31.5 U·mL^-1 and 29.6 U·mL^-1, respectively;Strain D5 possessed high corn stubble degrading ability with degrading rate of 29.8% in 10 days. The strain D5 was identified as Penicillium sp. by ITS sequence analysis, with tremendous potential for degrading corn stubble.