Ingesting probiotic yogurt containing Lactiplantibacillus plantarum OLL2712 improves glycaemic control in adults with prediabetes in a randomized, double-blind, placebo-controlled trial.

AIM: The ingestion of Lactiplantibacillus plantarum OLL2712 (OLL2712) cells has been shown to improve glucose metabolism by suppressing chronic inflammation in murine models and clinical studies. This study aimed to clarify the effect of OLL2712 on glycaemic control in healthy adults with prediabetes. MATERIALS AND METHODS: The study was a randomized, double-blind, placebo-controlled, parallel-group design. Adult participants with prediabetes [n = 148, glycated haemoglobin (HbA1c) range: 5.6%-6.4%, age range: 20-64 years] were assigned randomly to placebo or OLL2712 groups (n = 74/group) and administered daily for 12 weeks either conventional yogurt or yogurt containing >5 × 109 heat-treated OLL2712 cells, respectively. In addition, the participants were followed for 8 weeks after the discontinuation of either yogurt. The primary outcome was the changes in HbA1c levels at weeks 12 and 16 by analysis of covariance. RESULTS: The levels of HbA1c and glycoalbumin decreased significantly in both groups at week 12 in comparison with those at week 0, but only in the OLL2712 group at week 16. HbA1c levels decreased significantly at weeks 12 and 16 in the OLL2712 group in comparison with the placebo group (p = .014 and p = .006, respectively). No significant inter- and intragroup differences in HbA1c levels were observed at week 20. CONCLUSIONS: The ingestion of OLL2712 prevents the deterioration of glycaemic control and maintains the HbA1c levels within the normal range in adults with prediabetes; yogurt probably exhibits similar effects, which may contribute to reducing the risk of developing type 2 diabetes.

Anti-Fatigue Effects of Yogurt Fermented with Lactobacillus delbureckii subsp. bulgaricus OLL1073R-1 in Healthy People Suffering from Summer Heat Fatigue: A Randomized, Double-Blind, Placebo-Controlled Trial.

Fatigue caused by summer heat is a typical indefinite complaint along with anorexia, loss of sleep, stress, lack of motivation and, in some cases, catching a cold. Yogurt fermented with Lactobacillus delbrueckii subsp. bulgaricus OLL1073R-1 has been shown to stimulate the immune system and reduce the risk of catching colds. Here, we conducted a randomized, double-blinded, placebo-controlled trial to investigate whether ingesting this yogurt could ameliorate summer heat fatigue in 49 healthy males (median age 40.0 ± 6.0 years; 30⁻49 years) who felt fatigued every summer. Fatigue was evaluated by visual analogue scales (VAS) and the balance of sympathetic/parasympathetic nervous systems. After 12 weeks of ingestion in early autumn, the VAS fatigue scores in the yogurt group were lower than those of the placebo group. These results indicate that yogurt fermented with L. bulgaricus OLL1073R-1 can ameliorate summer heat fatigue lasting up to early autumn.

Predominant bacteria recovered from a periodontitis site in a hamster model raised by silk-ligature with Porphyromonas gingivalis infection.

We isolated oral bacteria that coexisted with Porphyromonas gingivalis in a hamster periodontitis model. As predominant bacteria in the periodontitis site, Collinsella-reltaed strains, Eubacterium-reltaed strains, Streptococcus suis-related strains, and Veillonella parvula-reltaed strains were detected. In addition, Actinomyces, Bacteroides, and P. gingivalis were also isolated predominantly. The results suggest that the bacterial composition of the periodontitis site in hamsters is complex, as in human periodontitis.

Interactions between salivary Bifidobacterium adolescentis and other oral bacteria: in vitro coaggregation and coadhesion assays.

Coaggregation assays were performed to investigate interactions between oral Bifidobacterium adolescentis and other oral bacterial species. Bifidobacterium adolescentis OLB6410 isolated from the saliva of healthy humans did not coaggregate with Actinomyces naeslundii JCM8350, Streptococcus mitis OLS3293, Streptococcus sanguinis JCM5708, Veillonella parvula ATCC17745 or Porphyromonas gingivalis OB7124, but it did coaggregate with Fusobacterium nucleatum JCM8532. Subsequent examination of biofilm formation on saliva-coated hydroxyapatite discs using FISH revealed that B. adolescentis OLB6410 could not directly adhere to the coated discs. It did, however, adhere to biofilms of A. naeslundii, V. parvula, and F. nucleatum, although it did not coaggregate with A. naeslundii nor with V. parvula. These results suggest that the adhesion of B. adolescentis to tooth surfaces is mediated by other oral bacteria. Heat- or proteinase K-treated F. nucleatum could not coaggregate with B. adolescentis. Similarly, the coaggregation and coadhesion of proteinase K-treated B. adolescentis were strongly inhibited. It is therefore probable that proteinaceous factors on the cellular surface of B. adolescentis and F. nucleatum are involved in their interaction. The data presented in this study add to our understanding of bifidobacterial colonization in the human oral cavity.

Distribution of salivary Lactobacillus and Bifidobacterium species in periodontal health and disease.

We surveyed the distribution of salivary Lactobacillus and Bifidobacterium species in periodontitis patients and healthy subjects. Approximately 700 lactobacilli and 300 bifidobacterial isolates were obtained from 16 young, orally healthy subjects (mean age +/- standard deviation: 21.0+/-2.0 y), 16 periodontitis patients (51.6+/-13.8 y), and 14 well-maintained former periodontitis patients (60.2+/-9.6 y). Among eleven Lactobacillus species detected in saliva, L. salivarius, L. gasseri, and L. fermentum were prevalent, but no species was specifically associated with periodontal health. In contrast, of four Bifidobacterium species, B. adolescentis was specifically (P<0.05) prevalent in young healthy subjects compared with the other two groups. Furthermore, the bifidobacterial count of the well-maintained subjects was the highest (P<0.05) among the groups. These results suggest that bifidobacterial count and species might be associated with periodontal health status and/or age.

Aerobic culture of Propionibacterium freudenreichii ET-3 can increase production ratio of 1,4-dihydroxy-2-naphthoic acid to menaquinone.

This is the first report on the production of both 1,4-dihydroxy-2-naphthoic acid (DHNA) and menaquinone by Propionibacterium freudenreichii ET-3. DHNA can be a stimulator of bifidogenic growth, and menaquinone has important roles in blood coagulation and bone metabolism. During anaerobic culture, DHNA and menaquinone concentrations reached 0.18 mM and 0.12 mM, respectively. The molar ratio between these products was approximately 3:2, which was not affected by culture pH and temperature over the ranges of 6.0-7.0 and 31-35 degrees C, respectively. As for organic acid, propionate and acetate accumulated at concentrations of 0.3 M and 0.15 M, respectively, and the propionate accumulation particularly inhibited further production of DHNA. To improve DHNA production, we switched from anaerobic condition to aerobic condition during the culture when lactose was depleted. DHNA concentration continued to increase even after lactose exhaustion, reaching 0.24 mM. In contrast to DHNA production, menaquinone production stopped after the switch to aerobic condition. The total molar production of DHNA and menaquinone was 0.3 mM irrespective of aerobic culture and anaerobic-aerobic switching culture. Therefore, the anaerobic-aerobic switching culture could increase the production ratio of DHNA to menaquinone. The DHNA concentration obtained from the anaerobic-aerobic switching culture was 1.3-fold higher than that in the anaerobic culture, because P. freudenreichii ET-3 utilized propionate accumulated in the medium via the reversed methylmalonyl CoA pathway under aerobic condition. The culture method proposed in this study could be applicable to industrial-scale fermentation using 1000 l of media, by which 0.23 mM DHNA was produced.

Isolation and identification of a new bifidogenic growth stimulator produced by Propionibacterium freudenreichii ET-3.

We have found a new growth stimulator for bifidobacteria in the culture broth of Propionibacterium freudenreichii ET-3. The bifidogenic growth stimulator (BGS) was purified by Diaion HP-20 column chromatography and preparative HPLC. Spectroscopic methods including 1H-NMR, UV, and LC-ESI-MS experiments indicated that the chemical structure of the bifidogenic growth stimulator was 1,4-dihydroxy-2-naphthoic acid (DHNA). Approximately 10 mg/L of DHNA was found to be produced in the culture broth of P. freudenreichii ET-3.