Recovery of Indigenous probiotic Lactobacillus plantarum Mut-7 on healthy Indonesian adults after consumption of fermented milk containing these bacteria

Probiotics are live microorganisms that confer health benefits on the host when administered in adequate amounts, such as to support the balance of gut microbiota. In this study, the selected indigenous probiotic strain, Lactobacillus plantarum Mut-7, was used as a starter culture to produce fermented milk. A total of 28 healthy Indonesian youngsters and adults (male/female: 16/12; age 19.4-22.9 years old; normal BMI range 18.6-22.7 kg/m²) were supplemented with the fermented milk. This study aimed to determine the recovery of L. plantarum Mut-7 through molecular analysis from the subjects feces after ingestion of 140 mL fermented milk containing 7.0 log₁₀ CFU/ml of L. plantarum Mut-7 for 15 days. Molecular detection was performed using the rep-PCR technique and sequencing of DNA 16S rRNA. Consumption of fermented milk containing L. plantarum Mut-7 enabled reduction of total E. coli and Coliform non-E. coli in several subjects. It was able to increase the total LAB and total L. plantarum in subjects' feces. The number of L. plantarum and mesophilic LAB increased by 5.5 ± 1.6 log₁₀ CFU/g, 1.8 ± 0.8 log₁₀. On the other side, thermophilic LAB increased by 2.8 ± 3.0 log₁₀ CFU/g in 23 out of 28 subjects. These findings proved that L. plantarum survived in the human gastrointestinal tract. Based on the molecular identification technique using rep-PCR technique and sequencing of gene 16S rRNA, two isolates had similarity to L. plantarum Mut-7 by a coefficient value of 100%.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-021-05046-z.

Oral administration of Lactobacillus plantarum 06CC2 prevents experimental colitis in mice via an anti‑inflammatory response

Dysbiosis of the enteric microbiota causes gastrointestinal diseases, including colitis. The present study investigated the beneficial effect of Lactobacillus plantarum 06CC2 in experimental colitis in mice. An experimental colitis model in C57BL6 mice was induced using dextran sulfate sodium. Mice were orally administered 06CC2 (06CC2 group) or PBS only (control group) by gavage. The disease activity index (DAI), histological grading, and colon tissue and colonic lamina propria mononuclear cells (LPMCs) were examined macroscopically and histopathologically, and the expression levels of inflammation‑associated cytokines (IL‑6, IL‑12, TNF‑α and IL‑10) in these samples were determined. Compared with the control group, the 06CC2 group exhibited a significantly lower DAI (1.5±0.8 vs. 0.2±0.3, respectively; P<0.05) and pathology score (6.3±1.5 vs. 3.8±1.3, respectively; P<0.05). IL‑10 expression in colonic LPMCs was higher in the 06CC2 group than in the control group, although there was no significant difference in IFN‑γ, IL‑6 or IL‑12 expression in colonic LPMCs between the two groups. In addition, 06CC2 stimulated the production of IL‑10 from CD11b‑positive cells and CD11c‑positive cells in the colon. The 06CC2 strain induced IL‑10 production in the colon and attenuated colon inflammation.

Lactobacillus paracasei strain 06TCa19 suppresses inflammatory chemokine induced by Helicobacter pylori in human gastric epithelial cells

Helicobacter (H.) pylori infection is an important risk factor for gastric cancer that causes gastric inflammation. Inflammatory chemokines such as interleukin (IL)-8 and regulated on activation normal T cell expressed and secreted (RANTES) are elevated in the gastric mucosa by H. pylori. This study aimed to investigate the effects of Lactobacillus paracasei strain 06TCa19, a probiotic strain, on IL-8 and RANTES expression and production induced by H. pylori using human gastric epithelial cell lines. Strain 06TCa19 was shown to suppress H. pylori-mediated elevation of gene expression related to these chemokines in MKN45 cells. The strain also suppressed the increase in IL-8 and RANTES products induced by H. pylori in AGS cells as well as in MKN45 cells. In MKN45 cells inoculated with H. pylori, strain 06TCa19 was shown to downregulate the activation of NF-κB and p38 MAPK signaling pathways. Additionally, the level of the CagA virulence protein of H. pylori in the MKN45 cells and the number of viable H. pylori adhering to MKN45 cells decreased with the addition of strain 06TCa19. Moreover, the strain 06TCa19 notably increased lactic acid in the supernatant of MKN45 cells. Thus, lactic acid released from strain 06TCa19 might have inhibited the adhesion of H. pylori to MKN45 cells and prevented the insertion of H. pylori CagA into the cells, and elevation of IL-8 and RANTES genes and proteins might be suppressed by downregulating the NF-κB and p38 MAPK pathways. Therefore, use of strain 06TCa19 may prevent H. pylori-associated gastric inflammation.

Isolation and Identification of Lactic Acid Bacteria from Traditional Dairy Products in Baotou and Bayannur of Midwestern Inner Mongolia and q-PCR Analysis of Predominant Species

In this study, traditional culture method and 16S rRNA gene analysis were applied to reveal the composition and diversity of lactic acid bacteria (LAB) of fermented cow milk, huruud and urum from Baotou and Bayannur of midwestern Inner Mongolia. Also, the quantitative results of dominant LAB species in three different types of dairy products from Baotou and Bayannur were gained by quantitative polymerase chain reaction (q-PCR) technology. Two hundred and two LAB strains isolated from sixty-six samples were identified and classified into four genera, namely Enterococcus, Lactococcus, Lactobacillus, Leuconostoc, and twenty-one species and subspecies. From these isolates, Lactococcus lactis subsp. lactis (32.18%), Lactobacillus plantarum (12.38%) and Leuconosto mesenteroides (11.39%) were considered as the dominated LAB species under the condition of cultivating in MRS and M17 medium. And the q-PCR results revealed that the number of dominant species varied from samples to samples and from region to region. This study clearly shows the composition and diversity of LAB existing in fermented cow milk, huruud and urum, which could be considered as valuable resources for LAB isolation and further probiotic selection.