Animal Biotechnology Centre, National Dairy Research Institute, Karnal, India.
PLoS One. 2009 Dec 1;4(12):e8099. doi: 10.1371/journal.pone.0008099.
Probiotic microorganisms favorably alter the intestinal microflora balance, promote intestinal integrity and mobility, inhibit the growth of harmful bacteria and increase resistance to infection. Probiotics are increasingly used in nutraceuticals, functional foods or in microbial interference treatment. However, the effectiveness of probiotic organism is considered to be population-specific due to variation in gut microflora, food habits and specific host-microbial interactions. Most of the probiotic strains available in the market are of western or European origin, and a strong need for exploring new indigenous probiotic organisms is felt.
An indigenous isolate Lp9 identified as Lactobacillus plantarum by molecular-typing methods was studied extensively for its functional and probiotic attributes, viz., acid and bile salt tolerance, cell surface hydrophobicity, autoaggregation and Caco-2 cell-binding as well as antibacterial and antioxidative activities. Lp9 isolate could survive 2 h incubation at pH 1.5-2.0 and toxicity of 1.5-2.0% oxgall bile. Lp9 could deconjugate major bile salts like glycocholate and deoxytaurocholate, indicating its potential to cause hypocholesterolemia. The isolate exhibited cell-surface hydrophobicity of approximately 37% and autoaggregation of approximately 31%. Presence of putative probiotic marker genes like mucus-binding protein (mub), fibronectin-binding protein (fbp) and bile salt hydrolase (bsh) were confirmed by PCR. Presence of these genes suggested the possibility of specific interaction and colonization potential of Lp9 isolate in the gut, which was also suggested by a good adhesion ratio of 7.4+/-1.3% with Caco-2 cell line. The isolate demonstrated higher free radical scavenging activity than standard probiotics L. johnsonii LA1 and L. acidophilus LA7. Lp9 also exhibited antibacterial activity against E. coli, L. monocytogenes, S. typhi, S. aureus and B. cereus.
The indigenous Lactobacillus plantarum Lp9 exhibited high resistance against low pH and bile and possessed antibacterial, antioxidative and cholesterol lowering properties with a potential for exploitation in the development of indigenous functional food or nutraceuticals.
益生菌微生物有利于改变肠道菌群平衡，促进肠道完整性和蠕动性，抑制有害细菌的生长，提高抗感染能力。益生菌越来越多地用于营养保健品、功能性食品或微生物干扰治疗。然而，由于肠道菌群、饮食习惯和特定的宿主-微生物相互作用的差异，益生菌的有效性被认为是特定于群体的。市场上可用的大多数益生菌菌株都来自西方或欧洲，因此强烈需要探索新的本土益生菌。
一种本土分离株 Lp9 通过分子分型方法鉴定为植物乳杆菌，对其功能和益生菌特性进行了广泛研究，即耐酸和耐胆盐、细胞表面疏水性、自动聚集和 Caco-2 细胞结合以及抗菌和抗氧化活性。Lp9 分离株可以在 pH 值为 1.5-2.0 的条件下孵育 2 小时，并且可以耐受 1.5-2.0%的鹅去氧胆酸胆汁。Lp9 可以去共轭主要胆盐，如甘胆酸和脱氧牛磺胆酸，表明其有降胆固醇的潜力。该分离株表现出约 37%的细胞表面疏水性和约 31%的自动聚集。通过 PCR 证实了存在假定的益生菌标记基因，如粘液结合蛋白 (mub)、纤维连接蛋白结合蛋白 (fbp) 和胆盐水解酶 (bsh)。这些基因的存在表明 Lp9 分离株在肠道中可能存在特定的相互作用和定植潜力，这也被与 Caco-2 细胞系的良好粘附率（7.4+/-1.3%）所证实。该分离株表现出比标准益生菌 L. johnsonii LA1 和 L. acidophilus LA7 更高的自由基清除活性。Lp9 还对大肠杆菌、单核细胞增生李斯特菌、伤寒沙门氏菌、金黄色葡萄球菌和蜡样芽孢杆菌表现出抗菌活性。
本土植物乳杆菌 Lp9 对低 pH 值和胆盐具有高抗性，具有抗菌、抗氧化和降低胆固醇的特性，有潜力开发本土功能性食品或营养保健品。
