绒毛栓孔菌液体培养过程中胞外酶活性的研究

Studies on Activities of Extracellular Enzymes in Liquid Culture of Trametes pubescens

本研究以绒毛栓孔菌为材料,采用液体培养的方法分析其在发酵过程中胞外酶的活性变化,并对其菌丝体生物量和发酵液pH值进行了测定。结果表明:胞外酶活性与菌丝体生长状况密切相关。菌丝体生物量增长呈"S"型,6～8d增长最快,第12天达到最大值,在此过程中漆酶、锰过氧化物酶、淀粉酶、羧甲基纤维素酶、果胶酶和蛋白酶活性均出现高峰。酶活性的变化表明,在液体培养过程中绒毛栓孔菌首先分解木质素,其次利用淀粉和纤维素作为碳源,蛋白质作为氮源。若要获得最大菌丝体生物量,缩短培养时间,就必须在培养过程中保证碳氮源的均衡供给。本试验说明不同的酶其分泌高峰期可以作为判断菌丝体营养利用情况和培养周期的依据,以此获取最大菌丝体生物量,为工业生产利用奠定基础。

In this study,we employed the fungal strain Trametes pubescens Cui7571 as experimental material to analyze the activities of extracellular enzymes in liquid culture,as well as to measure the mycelial biomass and pH values in liquid culture.The results demonstrated that the activities of extracellular enzymes were correlated with the mycelium growth.The increase of mycelial biomass presented S-like curve,which showed logarithmic increase of mycelial growth at the 6th to 8th days after inoculation then reached its peak on the 12th day.The growth peaks for laccase,manganese peroxidase,amylase,carboxymethylcellulose enzyme,pectinase and protease were all observed during the incubation stage.The variations of enzyme activities indicated that the strain （T.pubescens） decomposed lignin firstly,and then used starch and cellulose as carbon sources,protein as nitrogen source.In order to achieve the maximum mycelial biomass and shorten the culture time,it is necessary to provide the sufficient and balancing carbon and nitrogen sources in liquid fermentation.This study indicated that the secreted peaks of different enzymes might be used as criteria of judging the status of mycelial nutrition utilization and fermentation periods to harvest the maximum mycelial biomass for further large scale production.