Objective: The increase of multidrug resistance in bacteria has increased the efforts in search of alternative methods. The aim of the present study was to isolate and characterize the lytic phages and assess their lytic activity against a number of gram-negative bacteria. Materials and Methods: The phages and their respective hosts were isolated from wastewater collected from the municipal sewer system of Trabzon, Turkey. The lytic activities of phage were determined using the agar spot test. The identification and antibiotic susceptibility of host bacteria were determined using matrix-assisted laser desorption ionization time-of-flight mass spectrometry and Phoenix 100, respectively. The phages were characterized morphologically using transmission electron microscopy. One of the phages, Enteroc21, which has a broad-host-range, was further characterized by genome restriction endonuclease analysis and burst size. Results: Two phages infected strains of four different species, nine phages were able to infect 2-4 strains belonging to one or two species, and three phages showed lytic activity against only the hosts from which they were isolated. All phages belonged to the Siphoviridae, Myoviridae, and Podoviridae family based on trans- mission electron microscopy morphology. The Enteroc21 had more than 100 kb genome size and a burst size of 180 per infected cell. Most of the host strains were resistant to ampicillin, amoxicillin–clavulanic acid, and in particular, Achromobacter xylosoxidans TRAX 13 was multidrug-resistant showing resistance to cefepime, aztreonam, gentamicin, netilmicin, and ciprofloxacin. Conclusion: This study showed that the isolated phages have the potential to be used in phage therapy against various bacterial infections, including multidrug-resistant bacteria. Cite this article as: Khorshidtalab M, Durukan İ, Tufekci EF, Nas SS, Abdurrahman MA, Kiliç AO. Isolation and characterization of lytic bacteriophages from wastewater with phage therapy potentials against gram-negative bacteria. Eurasian J Med. 2022;54(2):157-164.

The increase in consumer demand for high-quality food products has led to growth in the use of new technologies and ingredients. Resistant starch (RS) is a recently recognised source of fibre and has received much attention for its potential health benefits and functional properties. However, knowledge about the fate of RS in modulating complex intestinal communities, the microbial members involved in its degradation, enhancement of microbial metabolites, and its functional role in body physiology is still limited. For this purpose, the current study was designed to ratify the physiological and functional health benefits of enzymatically prepared resistant starch (EM-RSIII) from maize flour. To approve the beneficial health effects as prebiotic, EM-RSIII was supplemented in rat diets. After 21 days of the experiment, EM-RSIII fed rats showed a significant reduction in body weight gain, fecal pH, glycemic response, serum lipid profile, insulin level and reshaping gut microbiota, and enhancing short-chain fatty acid compared to control. The count of butyrate-producing and starch utilizing bacteria, such as Lactobacillus, Enterococcus, and Pediococcus genus in rat’s gut, elevated after the consumption of medium and high doses of EM-RSIII, while the E. coli completely suppressed in high EM-RSIII fed rats. Short-chain fatty acids precisely increased in feces of EM-RSIII feed rats. Correlation analysis demonstrated that the effect of butyrate on functional and physiological alteration on the body had been investigated during the current study. Conclusively, the present study demonstrated the unprecedented effect of utilising EM-RSIII as a diet on body physiology and redesigning gut microorganisms.

Objective: The current study's objective was to evaluate the antioxidant activity and the phytochemical composition of the leaves of Rosa abyssinica and Justicia schimperiana . Methods: The crude extracts (80% methanol) and solvent fractions (aqueous, ethyl acetate and n-hexane) were prepared utilizing cold maceration and solvent fraction methods, respectively. The total alkaloid content (TAC) was quantified for the dried leaf powders. The total phenolic (TPC) and flavonoid (TFC) contents of the crude extracts were also assessed. The antioxidant activity of the crude extracts and solvent fractions was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and ferric reducing antioxidant power (FRAP) assays. Analysis using fourier transform infrared (FTIR) spectroscopy was also carried out. Results: The leaves of R. abyssinica exhibited a higher TAC (8.89%). Both TPC (11.58 ± 0.35 mg GAE/g of extract) and TFC (13.11 ± 0.97 mg QT/g of extract) were observed to be higher in the crude extract of R. abyssinica. Among all tested extracts, R. abyssinica 's n-hexane fraction (RANF) showed the highest activity specifically in DPPH (IC ₅₀ = 0.24 ± 0.01 mg/ml) and ABTS (IC ₅₀ = 0.15 ± 0.03 mg/ml) radical scavenging activity. The aqueous fraction (RAAF) exhibited the strongest activity in FRAP assay (6.49 ± 0.21 mg AA/g of extract). From the Fourier transform infrared (FTIR) spectroscopic analysis, C-H, C = O, O-H and C-O functional groups were identified in the crude extracts of both plants. Conclusion: These findings provide a basis for future investigation aimed at identifying bioactive compounds and exploring their potential therapeutic applications.

Occurrence of antimicrobial resistance (AMR) and antimicrobial resistance genes (ARGs) in Enterobacteriaceae and Acinetobacter spp. within agricultural environments represents a growing global health concern. Vegetables have been increasingly recognized as reservoirs of multidrug‐resistant (MDR) pathogens. The study aimed to detect ARGs in Enterobacteriaceae and Acinetobacter spp. from vegetable market chains and assess the clonal relationship of isolates. Antimicrobial susceptibility testing was conducted for a total of 170 isolates obtained from vegetables, irrigation water, and soil samples, and ARGs were detected by polymerase chain reaction (PCR). Conjugation assay was conducted, and genetic relatedness among bacterial isolates was assessed by ERIC‐PCR at a 70% similarity cut‐off. High resistance rate was observed to sulfamethoxazole/trimethoprim (34.0%) and cefepime (28.8%). Phenotypically, 23.5% (40/170) of isolates were extended spectrum β ‐lactamase (ESBL) producers and from meropenem resistance isolates 60% (6/10) were carbapenemase producers. Genes encoding for broad‐spectrum β ‐lactamases were detected in 30% (12/40) tested isolates, including those from irrigation water (50%; 3/6), vegetables (30.7%; 8/26) and soil (12.5%; 1/8) samples. Carbapenemase genes were detected in carbapenem resistant isolates from irrigation water (80%; 4/5) and vegetable (40%; 2/5) samples. The most prevalent β ‐lactamase genes identified were bla CTX‐M and AmpC ( n = 5 each), bla SHV ( n = 2), and bla TEM ( n = 1). Among carbapenemase genes bla NDM ( n = 6) was frequently detected, and bla KPC and bla VIM in a single isolate each. A sul1 gene was identified in 33.3% of isolates from vegetable and 15.3% of those from irrigation water. Four transconjugants were detected and successfully transferred resistance genes with conjugation frequency ranging from 1.48 × 10 ⁻⁵ to 3.3 × 10 ⁻⁶ out of 15 tested. ERIC‐PCR revealed diverse clonal lineages, although K. pneumoniae , K. aerogenes and E. coli isolates from vegetables and irrigation water displayed close genetic similarity (100%, 70%, and 78%), respectively. This study provided the first evidence of diverse β ‐lactamases and carbapenemase‐producing Enterobacteriaceae in Ethiopian vegetable market chains. These findings highlight the need for continued surveillance and improved food safety measures to mitigate potential public health risks posed by antimicrobial‐resistant pathogens in the food supply chain.

Introduction: The human immunodeficiency virus (HIV) continued to be the major threat to the world. The Ethiopian National Plan, as well as the UNAIDS target for the year 2021–2025, is to significantly reduce the transmission, enhance the prevention and control strategies to reduce deaths from the disease. Objective: This study aimed to investigate the determinants of knowledge, attitude, and practice (KAP) towards HIV/AIDS among Sayint Preparatory and General Secondary School students. Methods: An institution‐based cross‐sectional study was conducted from August to September 2023. Purposive sampling was used to select the site, and simple random sampling was used to recruit study participants. Results: The majority of the respondents had good knowledge (87.3%), positive attitude (88.9%), and good practice (88.6%). From the multivariate analysis, being from an urban area (AOR = 6.52, CI: 2.22–19.12), Grade 10 (AOR, 2.70; CI: 1.15–6.36), and Grade 11 (AOR, 3.69; CI: 1.47–9.30) and (AOR, 2.41–30.27) were factors associated with the knowledge about HIV/AIDS. Being married (AOR, 3.98, CI: 1.10–14.56) and obtaining information from family members (AOR, 0.30; CI: 0.11–0.80) were variables significantly associated with attitude towards HIV/AIDS. Conclusion: The KAP of the respondents towards HIV/AIDS was high, but misconceptions were also noted. Extensive sex education programs in schools should be devised to solve the risks associated with HIV/AIDS.