康氏木霉诱变株(NN—15B_7)酶粉的致突变性研究

Studies on the Mutagenicity of the Mutant Strain of Trichoderma koningii

给小鼠一次口服康氏木霉诱变株(NN—15B_7)粗酶粉,结果LD_(50)>15g/kg体重,属无毒物.Ames试验,康氏木霉纯酶粉3.83～5000μg/皿的5个试验组,对组胺酸缺陷型鼠伤寒沙门氏菌TA_(97) 、TA_(98)、TA_(100)三株菌在加与不加S_9活化系统中,回变菌落数与自发回变菌落数相近,无剂量效应关系.微核试验,用康氏木霉粗酶粉1.25、2.5和5g/kg体重连续2d给小鼠口服,结果各试验组微核率(1.6‰～1.8‰)均在正常范围内,PCE/RBC比值也与阴性对照组无显著差异.精子畸形试验,精子畸形率(1.88%～1.96%)与阴性对照组(1.78%)比较无显著差异,与阳性对照组(8.35%)比较差异非常显著(P<0.01).因此认为,康氏木霉诱变株(NN—15B_7)酶粉无毒性,无致突变性.

The mutagenicity of cellulase powder of Trichoderma koningii NN- 15B7 was studied by acute toxicity test, Ames test, micronucleus test of polychromatic erythrocytes in bone marrow and sperm abnormality test of mice. The results showed that its LD50 was higher than 15 g/kg b·w. There was no significant difference between the numbers of induced reversion mutation colony in test groups (His- auxotrophs of S. typhimurium: TA97, TA98, TA100) and control group in the presence or absence of metabolic activation system (S9). No relationship between dose and effect was observed. The frequencies of micronucleus of bone marrow in test groups and control group were 1.6‰-1.8‰. The ratioes of PCE/RBC in each test group and control group were similar. The morphological abnormality rates of sperm in test group were 1.88%-1.96%. Thus, it was considered to be nontoxic and nonmutagenic.