四株乳酸菌的加工性能

摘要

选用红霉素(Erythromycin)、氯霉素(Chloramphenicol)、四环素(Tetracycline)等常见的抗生素,用于测定4株乳酸菌在不同抗生素中的最高耐受浓度,并比较4株乳酸菌体外模拟胃肠道环境的耐受性.实验结果表明:4株乳酸菌均有不同程度的抗生素抗性作用.肠膜明串珠菌肠膜亚种(Leuconostoc mesenteroides subsp.mesenteroides)BD1710在四环素和氯霉素中的最高耐受浓度分别为1、2 μg/mL;植物乳杆菌ST-Ⅲ(Lactobacillus plantarum ST-Ⅲ)在氯霉素中的最高耐受浓度为1μg/mL;干酪乳杆菌BD0054(Lactobacillus casei BD0054)在四环素和氯霉素中的最高耐受浓度都为1 g/mL;干酪乳杆菌LC2W(Lactobacillus casei LC2W)对氯霉素的最高耐受浓度为1 μg/mL,4株乳酸菌都不耐红霉素.模拟胃肠道环境实验表明,在胃液环境下,ST-Ⅲ、LC2W的生长不受影响,但BD0054受到影响较大;在肠液环境下,ST-Ⅲ、BD1710生长不受影响,LC2W肠道不耐.高温处理过程,EDTA会加重菌体的损伤程度.冷冻干燥处理,存活率在90％～95％之间.%Three kinds of common antibiotic,tetracycline,erythromycin and chloromycetin were selected for measuring the maximum tolerated concentration(MTC) of four strains of lactic acid bacteria in different antibiotics.The in vitro gastrointestinal environmental tolerance of the four strains of lactic acid bacteria were compared.Four strains of lactic acid bacteria had different levels of resistance to three kinds of antibiotics,and the maximum tolerated concentration were obtained:Leuconostoc mesenteroides subsp.Mesenteroides BD 1710,MTC of tetracycline and chloramphenicol was 1,2 μg/mL respectively;Lactobacillus plantarum ST-Ⅲ,MTC of chloramphenicol was 1 μg/mL;Lactobacillus casei BD0054,MTC of tetracycline and chloramphenicol was 1 μg/mL;Lactobacillus casei LC2W,MTC of chloramphenicol was 1 μg/mL.Four strains of lactic acid bacteria were intolerance to erythromycin.The results of simulated gastrointestinal environment experiment demonstrated:in the simulated gastric juice environment,the growth of ST-Ⅲ and LC2W were unaffected,great harm were caused to BD0054;Under the environment of simulated intestinal juice,the growth of ST-Ⅲ and BD1710 were unaffected,LC2W do not endure.When four strains of bacteria were treated with high temperatures,EDTA will enhance the damage to these bacteria.After freeze drying treatment added with 10％ skim milk,the survival rate were 90％ ～95％.