Probiotic cell-free supernatant as effective antimicrobials against Klebsiella pneumoniae and reduce antibiotic resistance development.

This study evaluated the antimicrobial activity, resistance development, and synergistic potential of cell-free supernatant (CFSs) derived from Levilactobacillus brevis (Lb-CFS) and Lactiplantibacillus plantarum (Lp-CFS) against Klebsiella pneumoniae. Both CFSs exhibited potent growth inhibition, with minimum inhibitory concentrations (MICs) of 128 µg/mL and 64 µg/mL for Lb-CFS and Lp-CFS, respectively, and demonstrated dose-dependent bactericidal activity, achieving complete bacterial eradication at minimum bactericidal concentrations (MBC) within 6 h. The CFSs suppressed the expression of virulence genes (galF, wzi, and manC) and biofilm formation in a dose-dependent manner. Synergistic interactions were observed when combining CFSs with antibiotics, resulting in 2- to fourfold reductions in antibiotic MICs and MBCs. Notably, adaptive evolution experiments revealed significantly slower resistance development in K. pneumoniae against CFSs (twofold MIC/MBC increase) compared to antibiotics (16- to 128-fold increase) after 21 days. Furthermore, CFS-adapted strains exhibited increased antibiotic susceptibility, while antibiotic-adapted strains displayed cross-resistance to multiple antibiotics. No cross-resistance occurred between Lb-CFS and Lp-CFS, suggesting distinct adaptive mechanisms. These findings highlight the potential of probiotic-derived CFSs as effective antimicrobials with a lower propensity for inducing rapid resistance compared to conventional antibiotics, suggesting their promise in combating multidrug-resistant infections.

Coffee Husk By-Product as Novel Ingredients for Cascara Kombucha Production.

Kombucha, a fermented beverage, is gaining popularity due to its numerous beneficial health effects. Various substrates such as herbs, fruits, flowers, and vegetables, have been used for kombucha fermentation in order to enhance the flavor, aroma, and nutritional composition. This study aims to investigate the potential suitability of cascara as a novel ingredient for kombucha production. Our findings suggested that cascara is a suitable substrate for kombucha production. Fermentation elevated the total phenolic and flavonoid content in cascara, which enhanced the antioxidant, antibacterial, and prebiotic characteristics of the product. Furthermore, the accumulation of acetic acid-induced the pH lowering reached 2.7 after 14 days of fermentation, which achieved the microbiological safety of the product. Moreover, 14 days of fermentation resulted in a balanced amalgamation of acidity, sweetness, and fragrance according to sensory evaluation. Our findings not only highlight the potential of cascara kombucha as a novel substrate for kombucha production but also contribute to repurposing coffee by-products, promoting environmentally friendly and sustainable agricultural development.

Development of population pharmacokinetics model and Bayesian estimation of rifampicin exposure in Indonesian patients with tuberculosis.

BACKGROUND: Interindividual variability in the pharmacokinetics (PK) of anti-tuberculosis (TB) drugs is the leading cause of treatment failure. Herein, we evaluated the influence of demographic, clinical, and genetic factors that cause variability in RIF PK parameters in Indonesian TB patients. METHODS: In total, 210 Indonesian patients with TB (300 plasma samples) were enrolled in this study. Clinical data, solute carrier organic anion transporter family member-1B1 (SLCO1B1) haplotypes *1a, *1b, and *15, and RIF concentrations were analyzed. The population PK model was developed using a non-linear mixed effect method. RESULTS: A one-compartment model with allometric scaling adequately described the PK of RIF. Age and SLCO1B1 haplotype *15 were significantly associated with variability in apparent clearance (CL/F). For patients in their 40s, each 10-year increase in age was associated with a 10% decrease in CL/F (7.85 L/h). Patients with the SLCO1B1 haplotype *15 had a 24% lower CL/F compared to those with the wild-type. Visual predictive checks and non-parametric bootstrap analysis indicated good model performance. CONCLUSION: Age and SLCO1B1 haplotype *15 were significant covariates of RIF CL/F. Geriatric patients with haplotype *15 had significantly greater exposure to RIF. The model could optimize TB pharmacotherapy through its application in therapeutic drug monitoring (clinical trial no. NCT05280886).

Multi-Strain Probiotics Enhance the Bioactivity of Cascara Kombucha during Microbial Composition-Controlled Fermentation.

Kombucha is a widely consumed fermented tea beverage with diverse health benefits. In a previous study, we demonstrated that the use of cascara as a substrate results in a special kombucha beverage with high bioactivity. Traditional kombucha fermentation using a symbiotic culture of bacteria and yeast (SCOBY) can lead to inconsistent product quality because of the lack of control over microbial composition. We successfully isolated and identified yeast and bacteria, including Saccharomyces cerevisiae, Komagataeibacter rhaeticus, and Lactobacillus brevis that are appropriate starter cultures for cascara kombucha fermentation. We also demonstrated that a supplementation with lactic acid bacteria (LAB) and a mixture of S. cerevisiae and K. rhaeticus resulted in higher total polyphenol and flavonoid content of cascara kombucha compared with the traditionally fermented product using SCOBY as the inoculum. The free radical scavenging activity, inhibitory effects on α-amylase, tyrosinase activity, and antibacterial properties of cascara kombucha were also enhanced as a result of LAB supplement. These findings provide valuable insights into the controlled microbiological composition required for the fermentation of cascara kombucha, thereby ensuring consistent quality and enhanced bioactivity of the product. Further, the use of cascara as a substrate for kombucha production not only offers various health benefits and biological effects, but also repurposes by-products from the coffee industry, which contributes to sustainable development and is eco-friendly.