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The antimicrobial properties of ethanol, hot and cold extracts of some mushroom species (Russula vesca, Auricularia auricular, Pleurotus squarrosulus, Volvariaella vulvae) on some Gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus mirabilis, Salmonella typhi), Gram positive bacteria (Bacillus cereus, Staphylococcus aureus, Streptococcus pneumoniae) and yeast (Candida albicans) were investigated. The Minimum Inhibitory Concentrations (MIC) was evaluated for each of extracts of the mushrooms. Antimicrobial activity was performed by agar disc diffusion. The hot water extracts of R. vesca inhibited growth of E. coli, S. typhi, P. mirabilis and C. albicans. Ethanolic extract of A. auricular showed wide spectrum of antimicrobial effect against test organisms with the exception of S. typhi and P. aeruginosa. P. squarrosulus showed antimicrobial activity against K. pneumoniae (6.14 mm), S. pneumoniae (5.12 mm), and C. albicans (4.10). P. aeruginosa was resistant to almost all extracts of the four species of mushroom except the hot water extract of P. squarrosulus which showed zone of inhibition (3.41 mm). V. vulvae showed antimicrobial activity against S. typhi (4.60 mm). Ethanol and hot water extracts of most of the mushroom species contained more bioactive substance than cold water extract. The significance of antimicrobial activity of mushroom extracts was compared with the standard antibiotics (gentamicin, 5 µg/disc) using chisquare. There were significant difference between the mean zone of inhibition of the ethanol extract of P. squarrosulus and the standard antibiotic against test organisms at 5% level. The results obtained in this study suggest that P. squarrosulus possessed broad-spectrum of activity against microbial isolates used.

Background The 2019-nCoV which is regarded as a novel coronavirus is a positive-sense single-stranded RNA virus. It is infectious to humans and is the cause of the ongoing coronavirus outbreak which has elicited an emergency in public health and a call for immediate international concern has been linked to it. The coronavirus main proteinase which is also known as the 3C-like protease (3CLpro) is a very important protein in all coronaviruses for the role it plays in the replication of the virus and the proteolytic processing of the viral polyproteins. The resultant cytotoxic effect which is a product of consistent viral replication and proteolytic processing of polyproteins can be greatly reduced through the inhibition of the viral main proteinase activities. This makes the 3C-like protease of the coronavirus a potential and promising target for therapeutic agents against the viral infection. Results This study describes the detailed computational process by which the 2019-nCoV main proteinase coding sequence was mapped out from the viral full genome, translated and the resultant amino acid sequence used in modeling the protein 3D structure. Comparative physiochemical studies were carried out on the resultant target protein and its template while selected HIV protease inhibitors were docked against the protein binding sites which contained no co-crystallized ligand. Conclusion In line with results from this study which has shown great consistency with other scientific findings on coronaviruses, we recommend the administration of the selected HIV protease inhibitors as first-line therapeutic agents for the treatment of the current coronavirus epidemic.

Background and Objectives: Antibiotic-resistance among microbiota found within the oral cavity is a growing concern due to extensive use of antibiotics in dental practice both for therapeutic and prophylactic reasons, but has so far received little attention in recent time. The aim of this study was to determine the antibiogram of non-oral bacteria isolates from patients attending dental clinic at Federal College of Dental Technology and Therapy Medical Center Enugu (FEDCODTTEN) Methodology: A total of two hundred (200) oral swab samples were collected from patients with dental disease, placed in sterilized Brain Heart Infusion broth and immediately transported to the Microbiology Laboratory Unit of Federal College of Dental Technology and Therapy Enugu, for bacteriological analysis using standard microbiological methods for isolation and characterization. Antibiogram studies of non-oral bacteria was performed using the Kirby–Bauer disk diffusion method and the results were interpreted using the Clinical Laboratory Standard Institute (CLSI) zone diameter breakpoints. Multiple antibiotic resistance index (MARI) was determined for Multidrug Resistant (MDR) non-oral bacteria. Results: Phenotypic characterization of non-oral bacteria revealed an occurrence rate of S. aureus 35(17.5%) followed by E. coli 18(9.0%), Salmonella typhi 16(8.0 %) and K. oxytoca 4(2.0%) as the least predominant bacteria species. Among the oral site, lower right quadrant showed increase isolation rate of 30(15.0%) bacteria followed by lower left quadrant 23(11.5%) while upper right quadrant accounted 15(7.5 %) with the least isolation rate. There was no statistically significant difference in the prevalence of non-oral bacteria in right quadrant and left quadrant samples from dental disease patients (P < 0.05). Non-oral bacteria isolate exhibited 57.1-100% resistant to Ertapenem, colisitn, amoxillicin, azetronam, colistin, ampicillin and clindamycin with Multiple Antibiotic Resistant Index (MARI) ranged from 0.4-0.7, indicating high level of multi-drug resistance but were susceptible to ciprofloxacin 77.8%, gentamicin 100% and imipenem 100%. Conclusion: The high antibiotic resistant and increase multi-drug resistance outcome reported among non-oral bacteria in this study calls for strengthened efforts in antibiotic stewardship and infection prevention and control measures in dental practices with the need to implement regular awareness programs at time interval to control and manage multi-drug resistance bacteria through judicious use of antibiotic to re-establish dominance over multi-drug resistance non-oral bacteria implicated in dental diseases.

Background and Objectives: The biofilm-forming ability of Methicillin-Resistant Staphylococcus aureus(MRSA) strains have demonstrated the involvement of MRSA biofilm in antibiotic resistance, recalcitrant and persistent infections in humans. Despite a deeper understanding of the biofilm-forming ability of MRSAstrain, it is still essential to extend the research on the identification and antibiotic resistance profile of biofilm-forming MRSA causing infection among orthopedic wound patients. Methodology: A total of three hundred and thirty (303) patient-isolate of non-repeatable Staphylococcus aureus strains were obtained during the period of 2021 until 2022 from fracture and post-surgical orthopedic wound patients with wound duration >2months at the National Orthopedic Hospital, Enugu (NOHE). S. aureus were identified using conventional microbiological cultures Technique followed by confirmation of MRSA strain through Brilliance MRSA 2 Agar. Antibiotic Susceptibility testing (AST) of biofilm-forming MRSA was performed using the Kirby–Bauer disk diffusion method and the results were interpreted using the Clinical Laboratory Standard Institute (CLSI) zone diameter breakpoints. Multidrug Resistance (MDR) was determined for biofilm-forming MRSA. Result:Of the 303 isolate of S. aureus, MRSA strain accounted 86(28.4 %) and 78(25.7 %) from post-surgical wound and fracture wound respectively while biofilm forming MRSA was identified in 101(33.4%) MRSA strain consisting of high proportion 66(21.8 %) fromPost-surgical wound followed by fracture wound samples recording 35(11.6 %). Association between MRSA production and biofilm formation was considered statistically significant at P< .05. The proportion of biofilm-forming MRSA resistance to β-lactam accounted 71.4-100%, macrolide resistance recorded 65.7-92.4 %, lincosamideresistance 74.3-100 %, glycopeptide resistance proportion ranged from 62.8-100 % while low level of resistance to fluoroquinolones 19.7-42.9 % and Aminoglycoside 8.6-10.6 % was observed. Biofilm-forming MRSA isolate were MDR to one or more antibiotic antimicrobial agents in at least three categories withMDRIndex range ≥ 0.3 but majority of the isolate were 91.4% and 100% susceptible to Gentamicin and Imipenem. Conclusion: The invitro expression of biofilm formation among MRSA strain and their antibiotic resistance profile in this study makes them a potential threat and challenging pathogens with the ability to cause persistent infections in humans, especially among orthopedic wound patients. Thus the development of an antimicrobial stewardship program and regular detection of biofilm production is needed for timely intervention while judicious use of Imipenem and Gentamicin as a drug of choice for effective treatment of infection caused by biofilm-forming MRSA among orthopedic patients will avert the severity of infection. Further research of these sort should investigate the genotyping expression of a biofilm gene variant in other human diseases, different bacteria species, and orthopedic medical implant devices.