植物乳杆菌MA2的生物学特性研究

对Kefir源植物乳杆菌MA2的生物学特性进行了研究,结果显示,MA2菌株在MRS培养基初始pH为6.60,接种量为4%,37℃厌氧条件下培养18 h,活菌数可达到1.2×109cfu/mL。乙酸和乳酸为发酵液中的优势有机酸,且厌氧条件下发酵液中的有机酸的含量较高,厌氧发酵液中检测出的6种脂肪酸中C18∶1的含量最高。降胆固醇试验证明,低聚葡萄糖(GOS)可以促进MA2的胆固醇移除能力,移除率可达到70%;菌体细胞脂肪酸的测定结果显示MA2菌株降胆固醇的机理主要是吸附、吸收同化机理。MA2菌株的牛乳发酵试验结果显示其具有良好的产黏特性,在乳清培养基中胞外多糖产量可达380 mg/L。结合其良好的耐酸、耐胆盐特性,植物乳杆菌MA2具有良好的益生菌应用潜力。

Biological Characteristics of Lactobacillus plantarum MA2

Biological characteristics of Lactobacillus plantarum MA2 Strain from Kefir Grains was studied in this experiment,the results showed: the concentration of strain MA2 could reach 1.2×109 cfu/mL by the 18 h of anaerobic fermentation,when MRS initial pH was 6.60,inoculum was 4 %,temperature was 37 ℃;The quantitative analysis of the organic acids and fatty acid of strain MA2 showed that acetic acid and lactic acid was the main acid in both aerobic fermentation and anaerobic fermentation broth,C18∶1 was the most fatty acid in six kinds of fatty acid methyl ester detected in anaerobic fermentation broth.Additionally,glucose oligosaccharide(GOS) could improve the cholesterol removal of strain MA2,and the removal amount could might reach up to 70 %;The changes of cell fatty acid composition suggested that cholesterol removal mechanism of strain MA2 was mainly binding,absorbing cholesterol into cell and assimilation.Yoghurt fermentation test showed that MA2 has a good sticky characteristics,and the EPS production could reach up to 380 mg/L in whey medium;Combined with its excellent resistance to acid and bile tolerance characteristics,strain MA2 has a good potential probiotics market.