猪源乳酸杆菌与益生元组合筛选及其体外发酵特性

【目的】对3株乳酸杆菌和4种寡糖类益生元进行组合筛选,并探究其对猪结肠微生物体外发酵特性的影响。【方法】将3株乳酸杆菌(罗伊氏乳杆菌L45、植物乳杆菌L47和罗伊氏乳杆菌L63)分别添加至以菊粉(inulin)、低聚果糖(FOS)、低聚半乳糖(GOS)或乳果糖(lactulose)为唯一碳源的培养基中,结合菌株24 h的生长活性和产酸特性,筛选出最优组合;进一步利用体外发酵技术探究所筛选合生元组合对微生物和发酵特性的影响。【结果】L45和L63分别以FOS和Lactulose为碳源发酵时的生长曲线与葡萄糖相似,L47发酵Inulin和FOS的ΔOD600显著高于葡萄糖(P<0.05),且L47发酵Inulin产生的乳酸是葡萄糖的1.20倍,L47+FOS和L47+Inulin组合效应较好。体外发酵结果表明,与对照组相比,L47+FOS和L47+Inulin降低了发酵液中螺旋体门(Spirochaetes)的相对丰度,提高了乳杆菌属(Lactobacillus)和双歧杆菌属(Bifidobacterium)的相对丰度;L47+Inulin和L47+FOS显著提高了总短链脂肪酸含量(P<0.05);与L47+Inulin组相比,L47+FOS组乙酸和丁酸含量更高(P<0.05)。【结论】L47+FOS与L47+Inulin具有较好的组合效应,且具有改善猪结肠体外发酵的能力,提示L47+FOS和L47+Inulin作为合生元的发展潜力,两种组合在体内情况的效果有待深入研究。

Combination screening of lactobacillus spp. with prebiotics and analysis of its in vitro fermentation characteristics

Objective] Three lactobacillus strains and four prebiotics for symbiotic combination were screened and their effects on in vitro colonic fermentation characteristics were investigated. Methods] Lactobacillus reuteri L45, Lactobacillus plantarum L47 and Lactobacillus reuteri L63 were separately added to the medium with inulin, fructo-oligosaccharide, galacto-oligosaccharide or lactulose as the sole carbon source; the growth activity and acid production characteristics of the strains for 24 h were used to select the optimal combination; in vitro fermentation was used to investigate the effects of symbiotics on microorganisms and fermentation characteristics. Results] The growth curves of L45 and L63 fermentation with fructo-oligosaccharide and lactulose as carbon sources were similar to glucose respectively; the OD₆₀₀ of inulin and fructo-oligosaccharide with L47 was significantly higher than glucose (P<0.05), and the lactic acid concentration of inulin was 1.20 times higher than glucose; L47 with fructo-oligosaccharide and L47 with Inulin have better composite effects. In vitro fermentation results showed that the combination of two synbiotics (L47+fructo-oligosaccharide and L47+Inulin) significantly increased the relative abundance of Lactobacillus and Bifidobacterium compare to the control (P<0.05); L47+FOS and L47+Inulin increased the concentration of total short chain fatty acid (P<0.05). Conclusion] L47+fructo-oligosaccharide and L47+Inulin had favorable combination effects, implying that they had the development potential as symbiotics. The effect of both combinations in vivo remains to further investigated.