植物乳杆菌YSQ 规模化生产的低成本培养基配方优化

通过单因素试验、Plackett-Burman试验设计及响应面法筛选适于植物乳杆菌YSQ株大规模发酵的低成本培养基。结果表明：单因素试验确定培养基成分：碳源为玉米粉、次粉+蔗糖；氮源为豆粕；番茄汁作为生长因子供体。利用Plackett-Burman试验设计筛选出影响植物乳杆菌生长的4个主要因子：次粉、豆粕、K2HPO4和MnSO4。最陡爬坡、中心优化组合及响应面分析确定培养基各组分的最适添加量为：玉米粉10g/L、豆粕15.5g/L、次粉1.2g/L、蔗糖5g/L、番茄汁150mL/L、K2HPO4 1.1g/L、MnSO4 0.28g/L、MgSO4 0.3g/L。优化后，植物乳杆菌发酵18h的菌落总数从优化前的8.73×108CFU/mL(玉米粉、豆粕、次粉的混合料)提高到2.68×1010CFU/mL。

Optimization of Low-Cost Culture Medium for Large-Scale Production of Lactobacillus plantarum YSQ

One-factor-at-a-time method,Plackett-Burman design and response surface methodology were employed combinedly to optimize a growth medium based on low-cost agricultural by-products,like soybean meal,corn flour,wheat middlings and tomato juice for large-scale cultivation of Lactobacillus plantarum YSQ.The results showed that: 1) According to the results of one-factor-at-a-time experiments,in the culture medium,the carbon source were composed of corn flour,wheat middlings,the nitrogen source was soybean meal,and tomato juice was added as a growth factor.2) As identified by Plackett-Burman design,the main factor that affect the growth of Lactobacillus plantarum YSQ were wheat middlings,soybean meal,K2HPO4and MnSO4.3) Collectively,the results of steepest ascent tests,central composition design and response surface analysis indicated that the optimal growth medium was composed of corn flour 10 g/L,soybean meal 15.5 g/L,bran 1.2 g/L,sucrose 5 g/L,tomato juice 150 mL/L,K2HPO41.1 g/L,MnSO40.28 g/L,MgSO40.3 g/L.The total viable count was 2.68 × 1010CFU/mL after 18 h of culture in the optimized medium,while that obtained with a medium composed of a mixture of corn flour,soybean meal and bran was only 8.73 × 108CFU/mL.