CULTURE CONDITIONS FOR THE PRODUCTION OF TREHALOSE-HYDROLYSING ENZYMES FROM METARHIZIUM ANISOPLIAE
绿僵菌产海藻糖水解酶培养条件研究

The filamentous fungus Metarhizium produces several extracellular disaccharide-degrading enzymes, including trehalose-hydrolysing enzymes. These enzymes play an important role in the antagonistic action of Metarhizium against most insects. The effects of different carbon sources and nitrogen sources on the production of trehalose-hydrolysing enzymes from Metarhizium anisopliae var. acridum isolate CQMa102 were compared. The results indicated that CQMa102 could produce trehalose-hydrolysing enzymes in medium using glucose, maltose, sucrose, sorbitol or soluble starch as carbon source, but the best carbon source was soluble starch in terms of trehalose-hydrolysing activity and the number of isozymes produced, followed by sorbitol. Among the nitrogen sources tested, ammonium nitrogen and mixture of NaNO3 and organic nitrogen produced higher trehalose-hydrolysing activity than nitrate nitrogen. Comparison of trehalose-hydrolysing enzyme activity between the extracts of mycelia and the culture filtrate showed that the majority of trehalose-hydrolysing enzymes were secreted into liquid culture, only smaller amount of them were bound on cell wall.