A novel strain of Gram-negative, rod-shaped aerobic bacteria, identified as IY22, was isolated from the root nodules of Astragalus flavescens. The analysis of the 16S rDNA and recA (recombinase A) gene sequences indicated that the strain belongs to the genus Phyllobacterium. During the phylogenetic analysis, it was found that strain IY22 is closely related to P. trifolii strain PETP02^T and P. bourgognense strain STM 201^T. The genome of IY22 was determined to be 6,010,116 base pairs long with a DNA G+C ratio of 56.37 mol%. The average nucleotide identity (ANI) values showed a range from 91.7% to 93.6% when compared to its close relatives. Moreover, IY22 and related strains had digital DNA-DNA hybridization (dDDH) values ranging from 16.9% to 54.70%. Multiple genes (including nodACDSNZ, nifH/frxC, nifUS, fixABCJ, and sufABCDES) associated with symbiotic nitrogen fixation have been detected in strain IY22. Furthermore, this strain features genes that contribute to improving plant growth in various demanding environments. This study reports the first evidence of an association between A. flavescens and a rhizobial species. Native high-altitude legumes are a potential source of new rhizobia, and we believe that they act as a form of insurance for biodiversity against the threats of desertification and drought.

Bacteriophages are currently considered one of the most promising alternatives to antibiotics under the ‘One Health’ approach due to their ability to effectively combat bacterial infections. This study aimed to characterize Vibrio species in hatchery water samples collected from an aquaculture farm and investigate the biocontrol potential of their bacteriophages. Vibrio spp. (n = 32) isolates confirmed by LNA probe-based qPCR were used as hosts. Three Vibrio phages were isolated. IKEM_vK exhibited a broad host range, infecting V. harveyi (n = 8), V. alginolyticus (n = 2), V. azureus (n = 1), and V. ordalii (n = 1). IKEM_v5 showed lytic activity against V. anguillarum (n = 4) and V. ordalii (n = 1), while IKEM_v14 was specific to V. scophtalmi (n = 4). The morphological appearance of phages and their lytic effects on the host were visualized using scanning electron microscopy (SEM). All three phages remained relatively stable within the pH range of 6–11 and up to 60 °C. The lytic activities and biofilm inhibition capabilities of these phages against planktonic Vibrio cells support their potential applications in controlling vibriosis in aquaculture systems.

Schiff and azo-Schiff base derivatives were synthesized, identified and evaluated for their antimicrobial and antifungal activities against gram-positive bacteria, gram-negative bacteria and fungi such as Escherichia coli, Pseudomonas aureginosa, Staphylococcus aureus, Bacillus cereus, Salmonella typhimurium, Saccharomyces cerevisiae and Candida albicans. Chiral amides (2a-e) were synthesised by using D-Phenylglycine, L-Phenylalanine, L-valine, L-isoleucine and L-methionine. Experimental studies include the use of chiral amide derivatives (2a-e) of the five amino acids to synthesize the Schiff and azo-Schiff base derivatives of amides (3a-e, 4a-c and 4e). The structures of the compounds were determined by spectroscopic analyses (FTIR, 1H-NMR, 13C-NMR) and elemental analysis. Among the tested compounds, compound 3b and 3d were found to show the most potent inhibitory action against Gram positive and Gram negative bacteria.