乳酸杆菌作用下香蕉抗性淀粉的体外发酵研究

摘要

研究香蕉抗性淀粉在乳酸杆菌作用下的体外酵解作用及其对乳酸杆菌的生长增殖作用.香蕉抗性淀粉经过人工胃液和人工小肠液模拟体外消化后,接种健康大鼠粪便中经选择性培养的乳酸杆菌,模拟在结肠中乳酸杆菌的发酵作用,培养24 h后,观察乳酸杆菌的增殖情况;设定厌氧培养时间分别为0、4、8、12、16、20 h,测定pH值、乳酸和短链脂肪酸(short chain fatty acids,SCFAs)含量在发酵期间的变化.结果表明:培养基中添加香蕉抗性淀粉后,乳酸杆菌的数量增加了3.51 log cfu/mL.随着发酵时间的延长,pH值逐渐降低,短链脂肪酸和乳酸含量逐渐升高;发酵20 h后,短链脂肪酸总酸含量达到113.46 mmol/L,乳酸含量达到4.53 mmol/L.试验证明,经人工胃液和小肠液消化后的香蕉抗性淀粉更有利于肠道中乳酸杆菌的利用,并促进乳酸杆菌的生长繁殖和产酸.%The fermentation of banana resistant starch under the action of lactobacillus and its effect on the growth and proliferation of lactobacillus were studied.Banana resistant starch was digested in vitro by artificial gastric juice and artificial intestinal fluid.Lactobacillus was inoculated from the feces of healthy rats,and then the fermentation effect of banana resistant starch in colon was simulated. To observe the proliferation of lactobacillus,the anaerobic culture time was set at 0,4,8,12,16,20 h.The changes of pH value,lactic acid and short chain fatty acid contents were measured.The results showed that when the banana resistant was added to the medium,the number of lactobacillus increased by 3.51 log cfu/mL.With the prolongation of the fermentation time, pH value decreased and the content of short chain fatty acid and lactic acid increased gradually. After 20 h fermentation, the total acid content of short chain fatty acid was increased to 113.46 mmol/L, and the content of lactic acid was 4.53 mmol/L.It was proved that banana resistant starch digested with artificial gastric juice and small intestinal fluid is more favorable for the utilization of lactobacillus,and promote lactobacillus growth and reproduction and acid production.