两株真菌降解菜籽饼中植酸的研究

利用选择性培养基从土壤中分离到两株能降解植酸的丝状真菌。这些菌株能利用肌醇作为唯一的碳源和能源而生长。在液态发酵中植酸的降解率分别为74．4％和95．0％；在固态发酵中植酸的降解率为40％左右。某些金属离子对菌株的降解率的提高具有一定的促进作用。对温度、pH和水分等影响因子也进行了初步的探讨。经初步鉴定，这两株菌株中有一株为拟青霉（Paecilomycessp），另一株为青霉（Penicilliumsp．），它们均不产黄曲霉素素。

DEGRADATION OF PHYTIC ACID IN RAPESEED MEAL BY TWO STRAINS OF MOLDS

By using selective media, two strains of molds which are able to degradephytic acid were isolated from soil samples. These molds are able to use inositol asthe sole carb0n and energy sources for growth. In broth cultures, the degradationrates of phytic acid by these molds were 74.4% and 95.0%, respectively. However,in solid-state fermentation which used rapeseed meal as a raw material, thedegradation rate was about 40%. Several metal ions tested were able to enhance thedegradation rate of phytic acid. Factors such as temperature, pH and moisturecontent which affect the growth of molds were also explored. These two strains ofmolds were initially identified as Paecilomyces sp. and Penicillium sp.. They do notproduce any detectable amount of aflatoxins.