Department of Microbiology and Biotechnology Centre, Faculty of Science, The M. S. University of Baroda, Vadodara, Gujarat 390 002, India.
Br J Nutr. 2010 Jun;103(11):1620-8. doi: 10.1017/S0007114509993643. Epub 2010 Jan 14.
Lactobacilli isolated from various sources were identified on the basis of 16S-23S rRNA gene intergenic region amplification and subsequent sequencing of the smaller intergenic region. An in vitro analysis of probiotic properties including binding, ability to tolerate different concentrations of bile, survival in acidic buffer and antimicrobial activity of four different isolates and two standard strains (Lactobacillus plantarum American Type Culture Collection (ATCC) 8014 and L. rhamnosus GG (LGG)) was carried out. The ability of each isolate to stimulate Caco-2 cells, human peripheral blood mononuclear cells (PBMC) and THP-1 cells resulting in immunomodulation of these cells was analysed. Isolates L. rhamnosus CS25 and L. delbrueckii M and standard strain ATCC 8014 showed broad antimicrobial activity, and isolates CS25 (percentage of survival 6.9 % at pH 2.5, 5.1 % at pH 2.0) and L. plantarum CS23 (5.7 % at pH 2.5, 4.9 % at pH 2.0) have shown good tolerance to acidic pH. Isolate CS23 showed a good survival (14 %) after 2 h incubation in de Man, Rogosa and Sharpe (MRS) medium containing 3 % bile salts. Isolates CS23, CS25 and L. fermentum ASt1 could stimulate Caco-2 cells, human PBMC and THP-1 cells for a strong and varied immunomodulatory response in these cells. Though LGG showed poor antimicrobial activity as well as bile and acid tolerance, it was found to be the best binding strain tested. Child faecal isolate CS23 from the present study showed high binding ability (seventeen bacteria/Caco-2), high tolerance to acidic pH and bile salts and significant immunomodulation; therefore it is a good potential probiotic candidate.
从不同来源分离的乳杆菌基于 16S-23S rRNA 基因间隔区扩增，并随后对较小的间隔区进行测序进行鉴定。对包括结合能力、耐受不同浓度胆汁的能力、在酸性缓冲液中的存活能力以及四种不同分离株和两种标准菌株（植物乳杆菌美国典型培养物保藏中心（ATCC）8014 和 L. rhamnosus GG（LGG））的抗菌活性在内的益生菌特性进行了体外分析。分析了每种分离株刺激 Caco-2 细胞、人外周血单核细胞（PBMC）和 THP-1 细胞的能力，以及这些细胞的免疫调节能力。分离株 L. rhamnosus CS25 和 L. delbrueckii M 以及标准菌株 ATCC 8014 表现出广泛的抗菌活性，分离株 CS25（在 pH 2.5 时存活率为 6.9%，在 pH 2.0 时存活率为 5.1%）和 L. plantarum CS23（在 pH 2.5 时存活率为 5.7%，在 pH 2.0 时存活率为 4.9%）对酸性 pH 值具有良好的耐受性。分离株 CS23 在含有 3%胆盐的德氏乳杆菌培养基中孵育 2 小时后，存活率为 14%。分离株 CS23、CS25 和 L. fermentum ASt1 能够刺激 Caco-2 细胞、人 PBMC 和 THP-1 细胞，在这些细胞中产生强烈且不同的免疫调节反应。尽管 LGG 表现出较差的抗菌活性以及耐胆汁和酸的能力，但它被发现是测试的最佳结合菌株。本研究从儿童粪便中分离出的 CS23 具有高结合能力（每 17 个细菌/Caco-2）、高耐酸性和耐胆汁盐能力以及显著的免疫调节作用；因此，它是一种有潜力的益生菌候选菌株。
