降胆固醇植物乳杆菌I4增菌培养基响应面优化

Optimization of lowering cholesterol Lactobacillus Plantarum I4 enrichment mediumusing response surface method

采用响应面法对降胆固醇植物乳杆菌I4增菌培养基进行优化研究。通过Plackett-Burman试验设计筛选出影响菌体浓度的主要因素为蔗糖、酵母提取物和乙酸钠。经响应面优化后,得到蔗糖、酵母提取物和乙酸钠的最佳浓度分别为2.05%、1.54%、0.31%。优化后的增菌培养基中,菌体密度OD_(620)可达2.458,比MRS培养基OD_(620)值提高了23.7%,菌落单位提高了3.91倍,通过对I4菌发酵剂降胆固醇能力的测试,得出胆固醇降解率为36.2±1.75(%,n=3)。

Response surface methodology was used in lowering cholesterol Lactobacillus I4 enrichment medium optimization studies. Plackett-Burman experimental design was applied in screening the main factors affecting cell concentration of sucrose,yeast extract and sodium acetate. After the response surface to obtain a sugar,yeast extract. The optimum concentration of sodium acetate was 2.05%,1.54%,0.31%,the optimized enrichment medium cell density was up to 2.458 OD_（620）. The OD_（620） value improved 23.7% than in MRS medium,colony unit sincreased 3.91 fold. The test of the cholesterol-lowering ability of the formula indicates a degrading rate of 36.2±1.75（%,n=3）.