Effects of Lactocaseibacillus paracasei subsp. paracasei NTU 101 on gut microbiota: a randomized, double-blind, placebo-controlled clinical study.

BACKGROUND: Lactocaseibacillus paracasei subsp. paracasei NTU 101 (NTU101) is a well-known commercial probiotic with multiple health beneficial effects. In this study, the gut microbiota modulation effect of an NTU 101 product, Vigiis 101-LAB, on healthy human was investigated in a randomized, double-blind, placebo-controlled human trial. RESULTS: Vigiis 101-LAB significantly modulated human gut microbiota at fourth and sixth weeks of trial (anosim analysis, P = 0.001). It also significantly improved peristalsis (P = 0.003) and shortened defecation interval of subjects. The shift of gut microbiota is significantly fit with defecation interval (P = 0.009) and stool shape (P = 0.001) of subjects. CONCLUSION: Our results suggest that Vigiis 101-LAB promotes human intestinal health with improvement of peristalsis and fecal quality. The gut modulation effects of Vigiis 101-LAB subsequently raised the abundance of vitamin B7, vitamin K, pyrimidine and purine biosynthesis pathways. Vigiis 101-LAB may promote peristalsis via purinergic pathway and possibly conferring prophylactic benefits against irritable bowel syndrome with constipation. © 2024 Society of Chemical Industry.

Characterization of an antimicrobial substance produced by Lactobacillus plantarum NTU 102.

BACKGROUND/PURPOSE: Lactic acid bacteria (LAB) are used in a variety of bio-industrial processes, including milk fermentation, and have been reported to have bactericidal activities. We previously isolated Lactobacillus plantarum NTU 102 from homemade Korean-style cabbage pickles. The aims of this work were to perform a screen of the antimicrobial substances produced by L. plantarum NTU 102 and to characterize it. METHODS: In this study, we investigated the bactericidal activity of this LAB strain and demonstrated that the cell-free supernatant of L. plantarum NTU 102 had antimicrobial activity. RESULTS: The antibacterial activity was significantly decreased by proteolytic enzymes, including pepsin, proteinase K, and trypsin, suggesting that the antimicrobial substance had proteinaceous properties. Additionally, this activity was heat stable and not affected by alterations in the pH from 1.0 to 4.0. The antibacterial substance produced by L. plantarum NTU 102, which we named LBP102, exhibited a broad inhibitory spectrum. The active compound was identified by nuclear magnetic resonance (NMR) techniques (1H NMR and 13C NMR). The IUPAC name was 2-(2-1 mino-1-hydroxyethoxy) ethyl 2-methylpropanoate. The substance showed antibacterial activity against Vibrio parahaemolyticus, and completely inhibited the growth of V. parahaemolyticus on agar plates at a concentration of 75 µg/mL. CONCLUSION: The proposed antimicrobial substance, LBP102 was found to be effective against V. parahaemolyticus BCRC 12864 and Cronobacter sakazakii BCRC 13988. The remarkable effects of LBP102 against this and other pathogens indicated its potential as a natural preservative/food additive.

The implication of probiotics in the prevention of dental caries.

The current oral health crisis, whose causes are varied and complex, necessitates timely oral evaluation and early detection and treatment of oral health problems. Dramatic changes in eating habits and lifestyles are associated with the recent decline in oral health. Probiotics are "good" bacteria that support digestion and a healthy immune system and offer various health benefits to the host. Traditionally, probiotics have been used to improve gut health; the most common uses have historically been as a treatment or prevention of gastrointestinal infections and disease. During the last decade, studies have additionally suggested the intake of probiotics for oral health purposes. Probiotic use provides an effective strategy to combat oral disease, including the development of dental caries and periodontal infection. The aim of this review is to describe the beneficial roles of probiotic bacteria in the oral cavity and the potential mechanisms by which these bacteria exert their effects on oral health.

Alleviation of metabolic syndrome by monascin and ankaflavin: the perspective of Monascus functional foods.

The metabolites of Monascus with multiple benefits are popular subjects for the development of functional foods. The yellow pigments, monascin and ankaflavin, which are the constituent metabolites of M. purpureus, M. pilosus and M. ruber, are becoming the focus of research on Monascus. Monascin and ankaflavin are azaphilone compounds with similar structures that exhibit multiple beneficial effects including anti-inflammation, anti-oxidation, anti-diabetes, immunomodulation, attenuation of Alzheimer's disease risk factor, and anti-tumorigenic effects. Monascin and ankaflavin not only possess pleiotropic bioactivities, but are also more potent than monacolin K in lowering lipid levels and have lower toxicity. Monascin and ankaflavin act as the activators of PPARγ agonist/Nrf-2 that subsequently ameliorate metabolic syndrome. Following the intensive exploration of Monascus bioactivities in recent years, the focus of research on Monascus-functional foods has shifted from whole fermented products/extracts to specific bioactive compounds. Therefore, the production of monascin and ankaflavin is an important topic with respect to Monascus-functional foods. Although several genomic studies have paved the way for understanding the production of secondary metabolites in Monascus, efforts are still required to effectively manipulate the biosynthesis of secondary metabolites with genetic engineering and/or culture techniques.

Optimization of antimicrobial substances produced from Lactobacillus paracasei subsp. paracasei NTU 101 (DSM 28047) and Lactobacillus plantarum NTU 102 by response surface methodology.

Response surface methodology (RSM) was used to study the effects of medium composition and growth conditions on antimicrobial substances produced by Lactobacillus paracasei subsp. paracasei NTU 101 and Lactobacillus plantarum NTU 102. These strains are used in the food and pharmaceutical industries because of their beneficial effects on the human gastrointestinal tract and in immune modulation. The production of antimicrobial substances was optimized by the Box-Behnken experimental design. An empirical model was developed through RSM to describe the relationship between variables (molasses, soymilk, and incubation temperature). The maximum antimicrobial activity of L. paracasei subsp. paracasei NTU 101 was 12.50 AU/mL with 18.33 g/L molasses and 14.53 g/L soymilk at a temperature of 35.00 °C, whereas in MRS (de Man, Rogosa, and Sharpe) broth, the activity was 14.00 AU/mL. Similarly, the maximum antimicrobial activity of L. plantarum NTU 102 was 15.00 AU/mL with 20.56 g/L molasses and 13.54 g/L soymilk at a temperature of 36.50 °C, whereas in MRS, the activity was 13.50 AU/mL. The antimicrobial activities visualized in response surface plots were 12.26 and 15.59 AU/mL for NTU 101 and 102, respectively. The results derived from RSM regression were close to those obtained with the experimental design treatments. These results revealed that an alternative medium could be used for large-scale commercial production of the antimicrobial substances, with potential prospects for application.

Safety and risk assessment of the genetically modified Lactococci on rats intestinal bacterial flora.

The interaction between Lactococcus lactis NZ9000/pNZPNK and intestinal microflora was evaluated as a method to assess safety of genetically modified microorganisms (GMMs). L. lactis NZ9000/pNZPNK is one kind of GMM and able to produce the intracellular subtilisin NAT (nattokinase) under induction with nisin. The host strain L. lactis NZ9000 was a generally recognized as safe (GRAS) microorganism. Six groups of Wistar rats were orally administered with L. lactis NZ9000/pNZPNK and L. lactis NZ9000 for 6 weeks. Fecal and cecal contents were collected to determine the number of L. lactis NZ9000, L. lactis NZ9000/pNZPNK, Lactobacillus, coliform bacteria, beneficial bacteria Bifidobacterium and harmful bacteria Clostridium perfringens. The liver, spleen, kidney and blood were evaluated for the bacterial translocation. After 6 weeks consumption with GM and non-GM Lactococcus, no adverse effects were observed on the rat's body weight, hematological or serum biochemical parameters, or intestinal microflora. The bacterial translocation test showed that L. lactis NZ9000/pNZPNK did not translocate to any organ or blood. Bifidobacterium was significantly increased in feces after administration of both Lactococcus strains (L. lactis NZ9000 and L. lactis NZ9000/pNZPNK), while C. perfringens remained undetectable during the experiment. These results suggested that L. lactis NZ9000/pNZPNK could be safe in animal experiments and monitoring of the interaction between test strains and intestinal microflora might be applied as a method for other GMM safety assessments.