解淀粉芽孢杆菌LJ1对实验鼠的急性毒性研究

Acute toxic effect of Bacillus amyloliquefaciens LJ1 on rodents

解淀粉芽孢杆菌LJ1是从土壤中分离得到的1株对瓜类白粉病具有较好防效的细菌。为了解LJ1菌株对动物及人的安全性,测定了该菌株发酵液对实验鼠的急性毒性,以及处理后小鼠体内谷丙转氨酶(AST)、谷草转氨酶(ALT)和碱性磷酸酶(ALP)的含量及6种血相指标。结果发现:LJ1菌株发酵液对小鼠的急性经口毒性和对大鼠的急性经皮毒性均为"低毒"级(LD50>4 640 mg/kg);处理3 d后,小鼠血清中AST、ALT和ALP 3种酶的含量及血液中白细胞、红细胞数和血红蛋白的含量均明显升高,与对照相比差异显著(P<0.05),14 d后各项指标基本恢复至正常水平,与对照无显著差异。说明LJ1发酵液灌胃处理初期对小鼠的脏器功能有一定影响,但14 d后其对脏器的影响可逐渐恢复。因此推断LJ1发酵液对动物机体安全,该菌株有进一步研究开发为生防菌的价值。

Bacillus amyloliquefaciens LJ1 is a bacterium isolated from soil sample which showed good activity against melon powdery mildew. To identify the safety of LJ1 to animals and human beings, the acute toxicity of fermentation broth of LJ1 to rodents was tested, and the content of aspartate aminotransferase （AST）,alanine aminotransferase （ALT）, alkaline phosphatase （ALP） as well as 6 hemogram indexes in treated mice were detected. The results showed that LJ1 has little toxicity on mice by stomach toxicity tests and rats by skin toxicity tests （LDs0 〉 4 640 mg/kg） ;the content of AST, ALT and ALP in serum and the number of white blood cell, red blood cell and hemoglobin in blood of mice increased with significant difference （P 〈 0.05） comparing with that of the control group 3 days after treatment, all of the indexes recovered to normal level and there was no significant difference comparing with that of the control group （ P 〈 0.05 ） 14 days after treatment. The results suggested that the fermentation broth of LJ1 has some side effect on the viscera function of mice at preliminary stage,but that will be restored 14 days later. Therefore, it could be deduced that LJ1 is safe to animals and has potential in developing as biocontrol agent.