Metabolites Potentially Determine the High Antioxidant Properties of Limosilactobacillus fermentum U-21.

Many kinds of Lactobacillus are common occupants of humans' digestive tract that support the preservation of a balanced microbial environment that benefits host health. In this study, the unique lactic acid bacterium strain Limosilactobacillus fermentum U-21, which was isolated from the feces of a healthy human, was examined for its metabolite profile in order to compare it to that of the strain L. fermentum 279, which does not have antioxidant (AO) capabilities. By using GC × GC-MS, the metabolite fingerprint of each strain was identified, and the data were then subjected to multivariate bioinformatics analysis. The L. fermentum U-21 strain has previously been shown to possess distinctive antioxidant properties in in vivo and in vitro studies, positioning it as a drug candidate for the treatment of Parkinsonism. The production of multiple distinct compounds is shown by the metabolite analysis, demonstrating the unique characteristics of the L. fermentum U-21 strain. According to reports, some of the L. fermentum U-21 metabolites found in this study have health-promoting properties. The GC × GC-MS-based metabolomic tests defined strain L. fermentum U-21 as a potential postbiotic with significant antioxidant potential.

Isolation and Characterization of Extracellular Vesicles from Gastric Juice.

EVs are involved in local and distant intercellular communication and play a vital role in cancer development. Since EVs have been found in almost all body fluids, there are currently active attempts for their application in liquid diagnostics. Blood is the most commonly used source of EVs for the screening of cancer markers, although the percentage of tumor-derived EVs in the blood is extremely low. In contrast, GJ, as a local biofluid, is expected to be enriched with GC-associated EVs. However, EVs from GJ have never been applied for the screening and are underinvestigated overall. Here we show that EVs can be isolated from GJ by ultracentrifugation. TEM analysis showed high heterogeneity of GJ-derived EVs, including those with exosome-like size and morphology. In addition to morphological diversity, EVs from individual GJ samples differed in the composition of exosomal markers. We also show the presence of stomatin within GJ-derived EVs for the first time. The first conducted comparison of miRNA content in EVs from GC patients and healthy donors performed using a pilot sampling revealed the significant differences in several miRNAs (-135b-3p, -199a-3p, -451a). These results demonstrate the feasibility of the application of GJ-derived EVs for screening for miRNA GC markers.