植物乳杆菌LPL-1产细菌素发酵培养基优化

Optimization of Fermentation Medium of Lactobacillus plantarum LPL-1 for Plantaricin LPL-1 Production by Response Surface Methodology

乳酸细菌素是细胞在转录翻译过程中通过核糖体机制合成,并分泌到菌体体外的一类具有抑菌活性的蛋白质,细菌素具有无抗药性、无毒副作用及易被人体降解的特点,因此是一种天然的食品防腐保鲜剂。为了提高植物乳杆菌LPL-1所产细菌素的产量,以单增李斯特菌为指示菌,相对抑菌效价为效应值,通过响应面法对发酵培养基组成进行优化,确定了最优培养基组成。利用单因素试验与Plackett-Burman试验,确定了主要影响因素为葡萄糖质量分数、胰蛋白胨质量分数与吐温-80体积比,最陡爬坡试验与Box-Behnken响应面试验确定了最优培养基组成为:葡萄糖质量分数2.08%、酵母粉质量分数0.51%、胰蛋白胨质量分数1.02%、牛肉膏质量分数1%、吐温-80体积比1.02 mL/L、磷酸氢二钾质量浓度3 g/L、乙酸钠质量分数0.5%、硫酸镁质量浓度0.2 g/L、硫酸锰质量浓度0.3g/L、柠檬酸氢二铵质量浓度2 g/L、蒸馏水体积1 L。在此条件下细菌素效价(752.11 AU/mL)比优化前(286.67AU/mL)提高了1.62倍。因此,发酵培养基的优化为菌种与细菌素的产业化应用奠定了基础。

Bacteriocins from lactic acid bacteria（LAB） are ribosomally synthesized peptides or proteins that inhibit or kill the closely related species. Based on the merits of easy degradation by proteases,nonresistance and non-toxic side effects, plantaricin LPL-1 is a promising natural and safe biological preservative for food preservation industry. Aiming at the improvement of plantaricin LPL-1 fromLactobacillus plantarumLPL-1,the inhibitory activity（AU/mL） against Listeria monocytogenes 54002 was used as effect index,and the optimized medium composition was determined by response surface methodology. The major factors were determined as glucose,yeast extract and Tween-80 by single factor tests and Plackett-Burman tests. Based on the results of the steepest grade test and response surface methodology,the optimal medium composition was followed as glucose 2. 08%,yeast extract 0. 51%,tryptone 1. 02%,beef extract 1%,Tween-80 1. 02 mL/L,K_2HPO_4 3 g/L,NaAc 0. 5%,MgSO_4 0. 2 g/L,MnSO_4 0. 3 g/L,tri-ammonium citrate 2 g/L,and dd H_2O 1 L. Under the optimal conditions,the inhibitory activity reached up to 752. 11 AU/mL which was increased by 1. 62 times. Finally,the research provided insight into the potential use of bacteriocin as a food preservative in the food industry.