甘露寡糖对纯培养和共培养的乳酸杆菌体外生长的影响

Effects of Mannan-oligosaccharide on the Growth of Lactobacillus Pure Culture and Co-culture

摘要:

三株(S、L和M)猪源乳酸杆菌以甘露寡糖(mannan-oligosaccharide, MOS)为碳源体外纯培养或与猪源致病性大肠杆菌共培养, 研究MOS对乳酸杆菌的选择性生长作用。结果表明, 纯培养时, 三株菌MOS组的OD值和乳酸浓度均高于对照, pH均低于对照, 但菌株之间存在差异。共培养时, 乳酸杆菌和大肠杆菌都可利用MOS进行生长, 但乳酸杆菌的生长强于大肠杆菌, 产生较多的乳酸、显著降低pH(P＜0.05) , 这种促生长作用在最初的12 h较明显。

Abstract:

Effects of mannan-oligosaccharide (MOS) on the growth of Lactobacillus were investigated by pure culture of three swine originated Lactobacillus strains or co-culture with swine pathogenic E. coli. The pure culture results revealed that OD values and lactic acid concentration of three Lactobacillus strains in the MOS supplemented cultures were higher than those of the control group without MOS supplementation, a lower pH was observed for MOS supplement compared with that of the control group. The co-culture results showed that MOS were utilized by both Lactobacillus strains and swine pathogenic E. coli strain. But Lactobacillus grew faster than the latter. A significant increase in lactic acid concentration (P<0.05) and a significant decrease in pH (P<0.05) were observed in the MOS supplemented co-cultures compared with those of the control group or pathogenic E. coli pure culture. Moreover, the changes in numbers of Lactobacillus strains and the pathogenic E. coli strain, the elevation of lactic acid concentration and the reduction of pH were observed to be obvious during the first 12 h fermentation.