Bacteriophages (phages) are nano-sized viruses characterized by their inherent ability to live off bacteria. They utilize diverse mechanisms to absorb and gain entry into the bacterial cell wall via the release of viral genetic material, which uses the replication mechanisms of the host bacteria to produce and release daughter progeny virions that attack the surrounding host cells. They possess specific characteristics, including specificity for particular or closely related bacterial species. They have many applications, including as potential alternatives to antibiotics against multi-resistant bacterial pathogens and as control agents in bacteria-contaminated environments. They are ubiquitously abundant in nature and have diverse biota, including in the gut. Gut microbiota describes the community and interactions of microorganisms within the intestine. As with bacteria, parasitic bacteriophages constantly interact with the host bacterial cells within the gut system and have obvious implications for human health. However, it is imperative to understand these interactions as they open up possible applicable techniques to control gut-implicated bacterial diseases. Thus, this review aims to explore the interactions of bacteriophages with bacterial communities in the gut and their current and potential impacts on human health.

The bioengineering of phages to display ligands leads to specific targeting, reduced toxicity, enhanced cellular uptake of an incorporated drug/gene and, ultimately, increased therapeutic efficacy.

Background: Rapid emergence of multidrug resistant Staphylococcus aureus has resulted to difficulty in treatment of infections caused by such strains. The aim of this meta-analysis study was to determine the pooled prevalence of resistance of S. aureus to different antibiotics in Nigeria. Methods: Literature search for studies was done using Google scholar, PubMed, Science direct, and African Journal Online. The prevalence of S. aureus resistance to different antibiotics was evaluated using the meta-analysis proportion command in MedCalc software version 20.0 adopting a rand effect model. I² statistic and Egger test in MedCalc was used to evaluate the heterogeneity and the presence of publication bias among studies respectively. Results: A total of 40, 682 studies were retrieved through the database search of which 98 studies met the study inclusion criteria. Prevalence of resistance of S. aureus to different antibiotics ranges from 13 to 82%. Results showed a very high degree of resistance to penicillin G (82% [95% confidence interval (CI) 61%, 0.96%]), cloxacillin (77% [95% CI 64%, 88%]), amoxacillin (74% [95% CI 66%, 81%]), cefuroxime (69% [95% CI 51%, 85%]), ampicillin (68% [95% CI 53%, 81%]). Moderately resistance to erythromycin (47% [95% CI 40%, 53%]), chloramphenicol (47% [95% CI 37%, 56%]), methicillin (46% [95% CI 37%, 56%]), ofloxacin (24% [95% CI 18%, 31%]) and rifampicin 24% [95% CI 6%, 48%]). Low resistance was observed in vancomycin 13% (95% CI 7%, 21%). For each individual meta-analysis, high heterogeneity was observed with I² range (79.36–98.60%) at p-values ≤ 0.01). Egger’s tests for regression intercept in funnel plots indicated no evidence of publication bias. Conclusion: This meta-analysis study established that S. aureus in Nigeria has developed resistance to commonly used antibiotics such as the beta-lactam class antibiotics, sulphonamides, tetracyclines, chloramphenicol, and vancomycin. Hence it is imperative to develop programs to promote rational use of antimicrobial agents, infection prevention and control to reduce the incidence of antimicrobial resistance.

Due to the increasing limitations and negative impacts of the current options for preventing and managing diseases, including chemotherapeutic drugs and radiation, alternative therapies are needed, especially ones utilizing and maximizing natural products (NPs). NPs abound with diverse bioactive primary and secondary metabolites and compounds with therapeutic properties. Marine probiotics are beneficial microorganisms that inhabit marine environments and can benefit their hosts by improving health, growth, and disease resistance. Several studies have shown they possess potential bioactive and therapeutic actions against diverse disease conditions, thus opening the way for possible exploitation of their benefits through their application. Pseudoalteromonas spp. are a widely distributed heterotrophic, flagellated, non-spore-forming, rod-shaped, and gram-negative marine probiotic bacteria species with reported therapeutic capabilities, including anti-cancer and -bacterial effects. This review discusses the basic concepts of marine probiotics and their therapeutic effects. Additionally, a survey of the anticancer and antibacterial effects of Pseudoalteromonas spp. is presented. Finally, marine probiotic production, advances, prospects, and future perspectives is presented.

This research work aimed at developing an edible biopolymeric microcapsular wrapping (EBMW) integrating lytic bacteriophage particles for Salmonella enterica, with potential application in poultry feed for biocontrol of that pathogen. This pathogen is known as one of the main microorganisms responsible for contamination in the food industry and in foodstuff. The current techniques for decontamination and pathogen control in the food industry can be very expensive, not very selective, and even outdated, such as the use of broad-spectrum antibiotics that end up selecting resistant bacteria. Hence, there is a need for new technologies for pathogen biocontrol. In this context, bacteriophage-based biocontrol appears as a potential alternative. As a cocktail, both phages were able to significantly reduce the bacterial load after 12 h of treatment, at either multiplicity of infection (MOI) 1 and 10, by 84.3% and 87.6%, respectively. Entrapment of the phage virions within the EBMW matrix did not exert any deleterious effect upon their lytic activity. The results obtained showed high promise for integration in poultry feed aiming at controlling Salmonella enterica, since the edible biopolymeric microcapsular wrapping integrating lytic bacteriophage particles developed was successful in maintaining lytic phage viability while fully stabilizing the phage particles.

Background: Urinary tract infection (UTI) is one of the most chronic infections in humans, as well as the most common cause of multidrug-resistant (MDR) pathogen emergence, necessitating the quest for stringent antibiotic treatment. In the imperative search for effective drugs to combat MDR, silver nanoparticles (AgNPs) are given priority. The objective of this study was to synthesize, characterize, and evaluate the antimicrobial activity of AgNPs synthesized using Nigella sativa on MDR uropathogens. Methods: Urine samples of suspected UTI patients were collected using sterile sample bottles and cultured on different agar media to isolate and identify uropathogens using conventional method. All isolates were screened for multidrug resistance by disk diffusion method following the Clinical and Laboratory Standards Institute guideline with slight modification. N. sativa seed extract was used to synthesize AgNPs from aqueous solution of silver nitrate (AgNO₃). AgNPs formed were characterized using ultraviolet-visible (UV-Vis) spectroscopy, scanning electron microscope (SEM), dynamic light scattering, Fourier transform infrared spectroscopy, and X-ray diffraction spectroscopy (XRD). Antibacterial activities of synthesized AgNPs were assessed (in vitro) by disc diffusion method against MDR isolates, and cytotoxicity was evaluated using brine shrimp lethality assay. The formed AgNPs were characterized using UV-Vis, and antibacterial activity of synthesized AgNPs was assessed (in vitro) by impregnated disc diffusion method against MDR isolates. Results: Escherichia coli, Klebsiella sp., and Staphylococcus aureus were isolated. Multiple antibiotic-resistant indexes of the isolates ranged between 0.4 and 0.75 against the different standard antibiotics tested. The color change from pale yellow to dark brown was indicative of AgNP formation. UV-Vis spectrum of solution containing AgNPs exhibited peak wavelengths of 378 nm. Fourier transform infrared spectroscopic analysis showed that terpenoids, flavonoid, and phenols played an important role in the biosynthesis. Irregular shapes within nanoscale range were detected using SEM. XRD showed that the particles were crystalline in structure with an average size of 32 nm. The mean diameter zone of inhibition (in mm) for the different isolates at the dose of 100 μg/mL concentration showed maximum for E. coli (18 mm) followed by both Klebsiella sp. and S. aureus at 17 mm. Conclusion: The study underscores the efficacy of the plant-mediated nanoparticles as well as their potential for use as broad-spectrum antimicrobial agents for the management of MDR uropathogens.