The properties of intestinal bacteria/probiotics, such as cell surface hydrophobicity (CSH), auto-aggregation, and biofilm formation ability, play an important role in shaping the relationship between the bacteria and the host. The current study aimed to investigate the cell surface properties of fish intestinal bacteria and probiotics. Microbial adhesion to hydrocarbons was tested according to Kos and coauthors. The aggregation abilities of the investigated strains were studied as described by Collado and coauthors. The ability of bacterial isolates to form a biofilm was determined by performing a qualitative analysis using crystal violet staining based on the attachment of bacteria to polystyrene. These studies prove that bacterial cell surface hydrophobicity (CSH) is associated with the growth medium, and the effect of the growth medium on CSH is species-specific and likely also strain-specific. Isolates of intestinal lactobacilli from fish (Salmo ischchan) differed from isolates of non-fish/shrimp origin in the relationship between auto-aggregation and biofilm formation. Average CSH levels for fish lactobacilli and E. coli might were lower compared to those of non-fish origin, which may affect the efficiency of non-fish probiotics use in fisheries due to the peculiarities of the hosts’ aquatic lifestyles.

Purpose: The implementation of electron beam radiation coupled with the use of probiotics is one of the newest food processing technologies that may be used to ensure food safety and improve shelf life of food products. The purpose of this study was to evaluate the effect of 50–150-Gy electron beam irradiation on the antimicrobial activity of the putative probiotic strain Lactobacillus rhamnosus Vahe. Methods: Low-dose electron beam irradiation of lactobacilli cells was performed using the Advanced Research Electron Accelerator Laboratory’s electron accelerator, and the agar well diffusion method and Verhulst logistic function were used to evaluate the effect of radiation on anti–Klebsiella pneumoniae activity of the cell free supernatant of L. rhamnosus Vahe cells in vitro. Results: Our results suggest that 50–150-Gy electron beam irradiation decreases the viability of the investigated lactobacilli, but does not significantly change the probiotic’s activity against K. pneumoniae. Conclusions: Results indicate that the combined use of irradiation and L. rhamnosus Vahe might be suggested for non-thermal food sterilizing technologies.

Candidate Phyla Radiation bacteria are emerging members of the human microbiota, particularly in oral and gut environments. Saccharibacteria were previously identified in the gut microbiota of healthy individuals and women diagnosed with familial Mediterranean fever (FMF), a monogenic autoinflammatory disorder prevalent in the eastern Mediterranean region, including Armenia. This study aimed to assess the prevalence and diversity of Saccharibacteria spp. and its basebiont Schaalia odontolytica in FMF patients, explore gender differences, and evaluate the modulation potential of two locally produced probiotics: Lactobacillus acidophilus INMIA9602 Er317/402 (Narine^®, VITAMAX-E, Yerevan, Armenia) and Escherichia coli M-17 (Colibacteron^®, VITAMAX-E, Yerevan, Armenia). The abundance and behavior of saccharibacteria and S. odontolytica appear to vary depending on health status and sex. Placebo administration caused both quantitative and qualitative shifts, suggesting a possible interaction between Candidatus saccharibacteria spp. and Schaalia odontolytica, though the underlying biological significance remains to be clarified. Narine administration appeared to increase the abundance of Candidatus saccharibacteria operational taxonomic units (OTUs) in FMF women and S. odontolytica OTUs in FMF men, whereas Colibacteron selectively decreased certain OTUs, predominantly in FMF women. These findings underscore the need to further investigate saccharibacteria’s role in systemic inflammation and probiotic-mediated modulation of the gut microbiota.

Investigation of interbacterial antagonism in mixed cultures requires cultivation conditions that support the growth of physiologically distinct microorganisms. Standard systems often favor one interaction partner and distort observed outcomes, particularly during co-cultivation of Gram-positive and Gram-negative bacteria.

The “One Health” concept, traditionally centered on zoonotic pathogens and infectious disease management, has evolved to embrace the broader ecological interplay between humans, animals, and the environment. In recent decades, the accelerating challenge of antibiotic resistance has highlighted the fluid boundaries between pathogenic and commensal microorganisms, emphasizing that nature tolerates no strict divisions. Antibiotic resistance genes can readily transfer across microbial populations, blurring the lines between healthpromoting and pathogenic species. Consequently, modern “One Health” strategies must not only manage existing pathogenic threats but also foster sustainable microbial ecosystems that prevent future pathogen emergence. In this context, commensal and probiotic microorganisms play a vital role in stabilizing environmental, animal, and human microbiomes, serving as key agents in Green Microbial Technologies. This paper explores the paradigm shift from pathogen‐centered control to microbiome‐centered prevention, proposing that reinforcing beneficial microbial networks offers a sustainable, preventive approach to maintaining One Health at the agroecological interface.

Balanced investigation of interbacterial antagonism in mixed cultures requires cultivation conditions that support the growth of physiologically distinct microorganisms. Standard single-medium systems often favor one interaction partner and distort observed outcomes, particularly during co-cultivation of Gram-positive and Gram-negative bacteria.Lactobacillus spp. are commonly cultivated in De Man, Rogosa and Sharpe (MRS) medium, whereas Pseudomonas aeruginosa grows optimally in Luria–Bertani (LB) or nutrient broth. These media do not permit balanced co-cultivation and may suppress characteristic phenotypic traits associated with surface attachment and quorum sensing in P. aeruginosa.This article describes a composite liquid culture medium formulated by combining MRS broth with LB (Lennox modification) or nutrient broth in a defined volumetric ratio. The formulation enables co-cultivation of Pseudomonas aeruginosa and Lactobacillus spp. under static conditions while supporting surface-associated growth and qualitative assessment of quorum sensing–linked phenotypes. The method provides a standardized in vitro tool for studying antagonistic interactions and growth mode transitions in mixed bacterial cultures.The method can be applied for in vitro screening of antagonistic or quorum sensing–modulating effects in mixed bacterial cultures.