植物乳杆菌细菌素高产菌株的诱变选育及其对肉丸的防腐保鲜作用

为了提高细菌素产量并研究细菌素对肉制品的保鲜效果,本研究以植物乳杆菌JL-A65为出发菌株,对其进行常温等离子(ARTP)诱变、甲基硝基亚硝基胍(MNNG)诱变与基因组改组,并将细菌素与双乙酸钠复配后添加到肉丸中。结果表明,ARTP诱变最佳处理时间为40 s,经筛选得到两株突变株A7-10和A8-110,细菌素产量提高率分别为45.1%和48.9%。MNNG诱变的最佳处理浓度为1.5 mg/mL,经筛选得到两株突变株M2-58和M7-111,细菌素产量提高率分别为46.6%和31.3%。对植物乳杆菌进行基因组改组最终得到一株融合菌株F4-23,细菌素产量为413 mg/L,较原始菌株提高了103.48%。细菌素与双乙酸钠之间存在协同作用,可以使肉制品保质期较对照延长5 d。结论:利用理化诱变结合基因组改组可以获得细菌素高产菌株,细菌素与双乙酸钠复配后可以使肉丸保质期较对照延长5 d。细菌素对肉丸具有较好的防腐保鲜效果。

Screeging of High-yield Plantaricin Producing Stains Induced by Mutations and the Fresh-keeping Effect of Plantaricin on the Preservation of Meatballs

In order to obtain a high-yield bacteriocin producing strain,Lactobacillus plantarum JL-A65 was used as the starting stain and mutagenized with atmospheric and room temperature plasma(ARTP),methylnitro nitroguanidine(MNNG),then genome shuffling was applied to the mutants. In order to study the effect of bacteriocin on meatballs,bacteriocin and sodium diacetate were added to the meatball. The results showed that the optimal irradiation time of ARTP was 40 s,two mutants named A7-10 and A8-110 were obtained and their bacteriocin production by the mutants increased by 45.1% and 48.9% respectively compared with the starting strain. The optimum concentration of MNNG was 1.5 mg/mL,two mutant strains named M2-58 and M7-111 were obtained and their bacteriocin production by the mutants increased by 46.6% and 31.3% respectively compared with the starting strain. After four rounds of genome shuffling,a strain named F4-23 was obtained and the yield of it was 413 mg/L,which increased 103.48% compared with the starting stain. There was a synergistic effect between bacteriocin and sodium diacetate. Meat products using them as additives could extend shelf life by 5 days compared with control. Research showed that physical and chemical mutagenesis combined with genome shuffling was an effective method for obtaining high-yield bacteriocin producing strain. Meatballs using bacteriocin and sodium diacetate as additives could extend its shelf life by 5 days compared with control. Bacteriocin had a good antiseptic effect on fresh-keeping.