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目的比较肉毒梭菌检验食品样本处理、增菌培养基培养效果、温度及增菌液处理方式。方法对不同种类食品进行不同比例稀释,离心测上清液体积;将不同浓度的A型、B型、E型肉毒株分别接种在添加或不添加铁粉的商品化和自制疱肉培养基、胰蛋白酶胰蛋白胨葡萄糖酵母膏肉汤(TPGYT)上,分别在25℃、30℃、35℃进行比对培养,将添加杂菌的培养液用加热、无水乙醇处理及直接接种的方式进行分离比对。结果一般食品样本1∶1稀释上清液可用于毒素检测;自制和商品化疱肉培养基增菌效果无差异,加铁粉对B型和E型生长更好,TPGYT更适合E型肉毒生长;A型和B型肉毒梭菌在35℃左右生长更好,E型在25℃和30℃生长更好。乙醇处理增菌液分离效果良好。结论建议在新版标准中用1∶1稀释样本,使用添加铁粉的疱肉培养基和TPGYT增菌,疱肉培养基35℃增菌,TPGYT 30℃增菌,增菌液使用乙醇处理。
Objective To compare the effects of Clostridium botulinum in food sample processing, enrichment culture medium, temperature and bacteriostasis treatment. Methods The different kinds of food were diluted with different proportion and centrifuged to measure the volume of the supernatant. The different concentrations of A, B and E strains were respectively inoculated into commercial and homemade blister medium with or without iron powder , Trypsin, tryptone, dextrose yeast paste broth (TPGYT), respectively, at 25 ° C, 30 ° C and 35 ° C for comparison culture, the bacteria added to the culture medium with heating, ethanol treatment and direct inoculation Isolation comparison. Results The 1: 1 diluted supernatant of general food samples could be used for the toxin test. There was no difference in the bacteriostasis effect between the homemade and commercial blister cultures. Adding iron powder to grow better on type B and E, TPGYT was more suitable for botulinum toxin E Growth; Clostridium botulinum type A and B grow better at about 35 ° C, type E grow better at 25 ° C and 30 ° C. Ethanol-treated bacteria broth separation effect is good. Conclusion It is suggested that 1: 1 diluted samples should be used in the new standard, and the blister medium supplemented with iron powder and TPGYT should be added. The blister medium is enriched at 35 ℃, TPGYT is added at 30 ℃, and the broth is treated with ethanol.