双歧杆菌四联活菌体外模拟消化液耐受性的考察

考察双歧杆菌四联活菌中4种益生菌在模拟消化液中的耐受性。

按照现行版《中国药典》配制人工胃液与人工肠液，将4种益生菌分别加入其中，充分混匀，孵育0、15、30、60、90、120、180 min后，稀释、涂布与计数，绘制每种菌存活的衰减曲线，考察其存活率。

在人工胃液（pH 2.5～4.5）孵育3 h后，长双歧杆菌婴儿亚种（GMCC 0460.1）、嗜酸乳杆菌（GMCC 0460.2）、粪肠球菌（GMCC 0460.3）、蜡样芽胞杆菌（GMCC 0460.4）的存活率分别为53.23%～61.30%、75.31%～105.34%、90.76%～100.00%、81.02%～102.58%；在人工肠液（胆汁盐浓度0.03%～0.20%）孵育3 h后，长双歧杆菌婴儿亚种、嗜酸乳杆菌、粪肠球菌、蜡样芽胞杆菌的存活率分别为42.19%～71.49%、16.62%～45.03%、40.80%～69.50%、42.67%～95.43%。

4种益生菌在较长时间内耐受人工胃液（pH 2.5～4.5）和人工肠液（胆汁盐浓度0.03%～0.20%），菌体存活量下降不到1个数量级，对胃酸和胆盐的耐受性较强。由于健康人体内胃肠的环境类似于上述环境，预示其在健康人体消化道内能较好保持菌体生存能力，发挥药效活性。

The tolerance of bifidobacterium-quadruple probiotics to the simulated digestive fluid in vitro

ObjectiveTo observe the tolerance of bifidobacterium-quadruple probiotics in simulated digestive fluid. MethodsThe simulated gastric fluid and simulated intestinal fluid were prepared according to the current version of the Chinese pharmacopoeia. Four kinds of probiotics were separately added in the simulated fluids, thoroughly mixed, and incubated for 0 min, 15 min, 30 min, 60 min, 90 min, 120 min and 180 min respectively, then diluted, coated on the plates and counted. The survival attenuation curve of each bacterium was plotted and its survival rate was observed. ResultsAfter incubation in the simulated gastric fluid (pH 2.5 - 4.5) for 3 hours, the survival rates of Bifidobacterium longum subsp. infantis (GMCC 0460.1), Lactobacillus acidophilus (GMCC 0460.2), Enterococcus faecalis (GMCC 0460.3) and Bacillus cereus (GMCC 0460.4) were 53.23% - 61.30%, 75.31% - 105.34%, 90.76% - 100.00% and 81.02% - 102.58%, respectively. Likely, the survival rates of Bifidobacterium longum subsp. infantis, Lactobacillus acidophilus, Enterococcus faecalis and Bacillus cereus in the simulated intestinal fluid (bile salt concentration 0.03% - 0.20%) were 42.19% - 71.49%, 16.62% - 45.03%, 40.80% - 69.50% and 42.67% - 95.43%, respectively. ConclusionThe four probiotics showed strong tolerance under the conditions of incubation with simulated gastric fluid (pH 2.5 - 4.5) and simulated intestinal fluid (bile salt concentration 0.03% - 0.20%), with the survival numbers of them decreased less than one order of magnitude. The gastrointestinal environment of healthy people is similar to the simulated intestinal fluid, indicating that the four probiotics have strong tolerance to gastric acid and bile salts, which can effectively guarantee their pharmacological activities.