外源诱导及共培养对植物乳杆菌J23合成细菌素Lac-B23的影响研究

Effects of exogenous induction and co-culture on the production of the bacteriocin Lac-B23 from Lactiplantibacillus plantarum J23

中文关键词:  外源诱导  共培养  植物乳杆菌  细菌素  产量

英文关键词:exogenous induction  co-culture  Lactobacillus plantarum  bacteriocin  production

中文摘要:

      目的 研究外源诱导物及共培养对植物乳杆菌J23合成细菌素Lac-B23的影响, 提高细菌素产量。方法 利用双层琼脂牛津杯扩散法测定细菌素活性, 通过单因素实验、自诱导和共培养验证实验探究外源诱导物及共培养对细菌素J23产量的影响。结果 当初始pH为7、37℃培养12 h, 细菌素Lac-B23的产量达到最大值, 为2560 AU/mL。甘油和丙酮酸基本不影响细菌素Lac-B23的合成; 但酪氨酸、苯丙氨酸、精氨酸、谷氨酰胺和亮氨酸则能促进细菌素Lac-B23的产量。此外, 自我诱导研究发现植物乳杆菌J23发酵培养基中含有可以诱导细菌素Lac-B23合成的信号分子。一定浓度范围内, 植物乳杆菌J23与单增生李斯特菌或金黄色葡萄球菌共培养时可以提高细菌素Lac-B23的产量。然而, 诱导菌的灭活菌体和无细胞上清液并不能提高细菌Lac-B23的产量。结论 环境诱导因素对细菌素的合成有较大影响。初始pH、发酵温度、培养时间、酪氨酸、苯丙氨酸、精氨酸、谷氨酰胺和亮氨酸可以作为诱导因子, 提高细菌素Lac-B23的产量。此外, 共培养诱导分子没有分泌到培养基中, 可能需要活的诱导细菌来诱导细菌素Lac-B22的合成。

英文摘要:

      Objective To research the effects of exogenous induction and co-culture on the production of the bacteriocin Lac-B23 from Lactiplantibacillus plantarum J23 in order to increase the production of bacteriocin. Methods Double-agar oxford cup diffusion method was used to determine bacteriocin activity. The effects of exogenous inducers and co-culture on the production of bacteriocin J23 were investigated by single factor experiment, self-induction and co-culture verification experiments. Results At an initial pH of 7, temperature 37℃ and time 12 h, the production of the bacteriocin Lac-B23 reach a maximum, which was 2560 AU/mL. Glycerine and pyruvic acid were not found to increase the production of the bacteriocin Lac-B23. However, tyrosine, phenylalanine, arginine, glutamine and leucine could stimulate the synthesis of the bacteriocin Lac-B23. In addition, the results of self-induction showed that Lactiplantibacillus plantarum J23 fermentation medium contain signaling molecules that could induce the synthesis of bacteriocin Lac-B23. Within a certain concentration range, co-culturing technology could increase the production of the bacteriocin Lac-B23 when co-cultured with Listeria monocytogenes and Staphylococcus aureus. However, the production of the bacteriocin Lac-B23 was not improved by cell-free supernatants of inducer bacteria and heat-treated inducer bacteria. Conclusion Environmental factors play an important role in bacteriocin production. The initial pH, temperature, time, tyrosine, phenylalanine, arginine, glutamine and leucine, as inducible factors, can improve the production of the bacteriocin Lac-B23. In addition, the co-culture inducer molecule is not secreted into the medium, and living inducer bacteria may be necessary to improve the production of the bacteriocin Lac-B23.