Reportedly, a relationship exists between intestinal microflora and obesity-related lifestyle diseases. Blautia spp. a major intestinal microbiota, accounts for 3–11% of human intestinal microflora. Epidemiological reports have described that people with more visceral fat have less Blautia hansenii in their intestinal tract irrespective of age or gender. However, the effect of oral administration of heat-sterilized Blautia hansenii on obesity has not been clarified. Therefore, the aim of this study was to evaluate the effects of dietary Blautia hansenii administration on obesity in high-fat-diet-induced obesity in a mouse model. Heat-sterilized cells of Blautia hansenii were used. C57BL/6J mice (normal mice, n = 7) were fed with each experimental diet for nine weeks. Diets for experimentation were: normal-fat (NF) diets, high-fat (HF) diets, and high-fat + Blautia hansenii (HF + Blautia) diets. The HF + Blautia group was administered about 1 × 10⁹ (CFU/mouse/day) of Blautia hansenii. During the periods of experimentation, body weight, food intake, water consumption, and fecal weight were recorded, and glucose tolerance tests were performed. Subsequently, the white adipose tissue (WAT) weight and serum components were measured. Short-chain fatty acid contents in the feces and cecum were analyzed. Furthermore, changes in the intestinal microflora were analyzed using meta-genomics analysis. Results showed that the total weight of WAT in the HF + Blautia group was significantly lower (13.2%) than that of the HF group. Moreover, the HF + Blautia group exhibited better glucose tolerance than the HF group. Productivity of short-chain fatty acids in the intestinal tract was at a significantly (p < 0.05) low level in the HF group; on the other hand, it recovered in the HF + Blautia group. Furthermore, there was a higher ratio of Blautia (p < 0.05) in the intestinal tracts of the HF + Blautia group than in the HF group. These results suggest that Blautia hansenii administration suppresses obesity induced by a high-fat diet.

The purpose of this study was to improve the efficiency of the microbiological assays for biotin, niacin, and pantothenic acid by using lyophilized cells from Lactobacillus plantarum ATCC 8014. The use of lyophilized cells as an inoculum was assessed to avoid time-consuming processes like cell precultivation and washing. The authors also examined the effects of various protectants such as skim milk, sucrose, sorbitol, and trehalose on the assay. The viable cell counts of the lyophilized cells were found to be approximately equal for different protectants. The standard curves for biotin, niacin, and pantothenic acid concentrations obtained using lyophilized cells with sucrose and intact cells gave similar linear ranges. Furthermore, the measured vitamin concentrations of the standard reference material 3280 were in the range of the established values. Therefore, lyophilized cells with sucrose are potential alternative inocula for the turbidimetric method. This will increase the overall convenience associated with microbiological assays.

Reuterin is a broad-spectrum antimicrobial substance produced by lactic acid bacteria, and most previous studies have reported that reuterin is only produced under anaerobic conditions. If there are lactic acid bacteria that also produce it under aerobic conditions, it could be applied to fermented foods. In this study, it was found that Lactobacillus coryniformis WBB05 showed optimal reuterin production (123 mM reuterin from 200 mM glycerol) when incubated aerobically at 20°C. Furthermore, the minimum inhibitory concentration (MIC) of reuterin was determined for starter lactic acid bacteria strains and cheese moulds. MIC toward Penicillium camemberti was 0.125 mM and the white mould starter was much more sensitive than other moulds.

This paper reveals the technological properties of lactic acid bacteria isolated from raw milk (colostrum and mature milk) of Wagyu cattle raised in Okayama Prefecture, Japan. Isolates were identified based on their physiological and biochemical characteristics as well as 16S rDNA sequence analysis. Streptococcus lutetiensis and Lactobacillus plantarum showed high acid and diacetyl-acetoin production in milk after 24 h of incubation at 40 and 30°C, respectively. These strains are thought to have potential for use as starter cultures and adjunct cultures for fermented dairy products.

BACKGROUND: Fermenting soy milk with lactic acid bacteria is challenging. Generally, carbohydrates are added to enhance the acid production in soy milk. However, the yoghurt starter Lactobacillus delbrueckii subsp. bulgaricus did not succeed in fermenting soy milk supplemented with carbohydrates. If this yoghurt starter could be used with soy milk, it is expected that it would produce a yoghurt‐like flavour, making soy yoghurt more appealing. In this study, we aimed to ferment soy milk using Lb. delbrueckii subsp. bulgaricus and pseudovitamin B₁₂‐producing lactic acid bacteria.RESULTS: Loigolactobacillus coryniformis SAB01 was found to produce corrinoid in soy milk, with the highest production being observed at 20 °C. The produced corrinoid was identified as pseudovitamin B₁₂ using ultra‐performance liquid chromatography‐quadrupole time‐of‐flight mass spectrometry. Another bacterial strain, Lb. delbrueckii subsp. bulgaricus NBRC 13953, was examined for its ability to produce lactic acid in soy milk. Compared with soy milk supplemented with glucose or cyanocobalamin alone, the highest lactic acid production was observed in soy milk supplemented with both glucose and cyanocobalamin. These findings indicate that the combined addition of glucose and cyanocobalamin enhances lactic acid production by strain NBRC 13953 in soy milk. We accordingly examined lactic acid production in soy milk inoculated with strains SAB01 and NBRC 13953, and found that a substantial quantity of lactic acid was produced when glucose was added to soy milk.CONCLUSIONS: Our findings in this study indicate that the growth of Lb. delbrueckii subsp. bulgaricus NBRC 13953 was promoted by the pseudovitamin B₁₂ produced by Loigolactobacillus coryniformis SAB01, thereby suggesting a novel symbiotic relationship between these two lactic acid bacteria in soy milk. © 2025 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

This research paper investigated the hypothesis that the high production of 3-methylbutanal by lactic acid bacteria is achieved not only through a direct metabolic pathway but also via an indirect pathway. 3-methylbutanal is a flavour compound that contributes to the sensory profile of various cheeses, often described as nutty, malty, or chocolate-like depending on its concentration and the cheese matrix. Although it is desired in certain cheese varieties, its acceptability varies among different cheese types. Among the various compounds responsible for this nutty scent, 3-methylbutanal plays a pivotal role. Certain strains of lactic acid bacteria are known to produce 3-methylbutanal from leucine, via both direct and indirect pathways. While it has commonly been assumed that the direct pathway is the primary mechanism, this study reports the discovery of Lactococcus cremoris AJ01, which produces 3-methylbutanal predominantly through an indirect pathway. We first investigated the effects of milk fermentation conditions on 3-methylbutanal and acid production by strain AJ01. The effect of leucine supplementation on 3-methylbutanal production was then examined. Finally, we explored the metabolic pathway responsible for 3-methylbutanal synthesis in this strain, determined the nucleotide sequence of the pyruvate dehydrogenase gene involved in the indirect pathway, and evaluated its enzyme activity to assess its contribution to production. When cultured in milk at 20 °C, strain AJ01 produced titratable acidity at >0.6% and 3-methylbutanal at >6 mg/kg within 18 h. Adding leucine to the milk enhanced 3-methylbutanal production, while excessive leucine supplementation inhibited it. Strain AJ01 exhibited activity of pyruvate dehydrogenase, while no activity of α-keto acid decarboxylase, the direct-pathway enzyme, was detected, suggesting that it produces 3-methylbutanal via the indirect pathway. These findings may contribute to the effective management and enhancement of flavour profiles in fermented dairy products, particularly cheeses.