Microbial contamination of Naira notes circulating in Bauchi metropolis: prevalence, microbial load and detection of extended spectrum beta-lactamase producing Gram-negative bacteria

Background: Globally, contamination of banknotes with various microbial species is increasingly being reported. This usually results from improper handling during exchange of goods and services. In the present study, we aimed to determine the microbial load, prevalence and the presence of Extended Spectrum Beta Lactamase (ESBL) among bacteria isolated from the Nigerian Naira notes circulating in Bauchi metropolis.Methodology: A total of 400 Naira notes of various denominations were randomly collected aseptically, cultured and total viable counts determined. The isolated microbial species were identified using standard microbiological techniques. Antibiotic susceptibility of the isolates and detection of ESBL were determined by Kirby-Bauer’s disc diffusion method and Double Disc Synergy Test (DDST), respectively.Results: All the 400 samples collected were contaminated with various microbial species. The highest mean colony count was detected in 20 Naira notes (28.5%), while the least was observed in 1000 Naira note (3.3%). Fourteen different microbial species were isolated from the contaminated currency notes, predominantly Escherichia coli (25.0%), and Staphylococcus aureus (12.0%). Some fungal species mainly Aspergillus flavus and Aspergillus niger were also isolated. Majority of the bacteria isolates resistant to the third generation cephalosporins (72.1%) were ESBL positive.Conclusion: The study shows that Naira notes circulating in Bauchi metropolis were heavily contaminated with various microbial species, and a high proportion of the isolated Gram-negative bacteria were ESBL producers. Efforts should thus be made to improve hygiene practices in the study area. Importantly, businesses should be encouraged to adopt the use of electronic transactions. Keywords: Currency notes, Naira, Microbial contamination, ESB

Antibacterial and Anti-Biofilm Activities of Neocarya Macrophylla Against Clinical Bacterial Isolates

Background: The increasing threat of bacteria resistant to current antibiotics underscores the need for an alternative source of antimicrobial agents. This study was designed to investigate the antibacterial and antibiofilm activity of Neocarya macrophylla against two important human pathogens commonly associated with biofilm-related infections.Methods: The methanolic extract of N. macrophylla leaves and its n-butanol and ethylacetate fractions were screened in-vitro for their antimicrobial activity using agar well diffusion technique while the antibacterial and antibiofilm activity of the extract and its fractions were investigated against clinical isolates of S. aureus and P. aeruginosa using microbroth dilution technique and microtiter plate method respectively.Results: The methanolic leaf extract and its fractions exhibited substantial antimicrobial activity. The n-butanol and ethylacetate fractions showed highest activity against P. aeruginosa and S. aureus respectively. The MIC and MBC of the extract and its fractions against both S. aureus and P. aeruginosa ranged from 3.125-37.5 mg/ml and 6.25-75 mg/ml respectively. In addition, a concentration-dependent antibiofilm activity against the test organisms was also observed with the ethylacetate fraction exhibiting the highest antibiofilm activity.Conclusion: The extracts and fractions of N. macrophylla exhibited remarkable antibacterial and antibiofilm activities against S. aureus and P. aeruginosa. The plant thus can be considered as a potential source of bioactive principles in the continuous fight against bacterial virulence and resistance.Keywords: Neocarya macrophylla, Antimicrobial activity, Antibiofilm activity, Antimicrobial resistance

Antimicrobial Peptide Design, Molecular Docking and ADMET Studies Against the Methicillin-Resistant Staphylococcus aureus and Carbapenem-resistant and Carbapenemase-producing Pseudomonas aeruginosa: Prediction of novel anti-MRSA and anti-CRPA AMPs

Carbapenem-resistant and carbapenemase-producing Pseudomonas aeruginosa (CRPA) and methicillin-resistant Staphylococcus aureus (MRSA) are two pathogens that are resistant to currently available antimicrobials. As an alternative to effective medication molecules, antimicrobial peptides (AMPs) have the potential to cure superbug-caused infections effectively. Two new AMPs (ama1 and ama2) were designed utilizing a knowledge-based technique with optimal parameters. First, the PEP-FOLD 3.5 server made a de novo prediction of the AMPs' three-dimensional (3D) structure, which was validated using PROCHECK of SAVES v6.0 by checking the amino acid locations in the Ramachandra plot. Then, protein-peptide docking simulations of the predicted AMPs and reference AMP (Aurein 1.2) for positive control were performed using the HPEPDOCK docking web server, followed by the computation of the AMPs' physicochemical parameters and toxicity profile using the ProtParam and vNN-ADMET web servers, respectively. The sequences for ama1 and ama2 were AWGKIKALR and IKWLRLAKP, respectively. Docking analysis revealed that the antibacterial activity of ama1 and ama2 was superior to that of Aurein 1.2 against CRPA-resistant enzyme (6ew3), respectively. However, ama1, ama2, and Aurein 1.2 inhibited the activity of MRSA-resistant protein (4c12). Both the physicochemical qualities and the toxicity profiles were advantageous. Therefore, the in-silico-derived AMPs could serve as a pharmaceutical candidate for developing multidrug-resistant bacteria-effective antimicrobials. HIGHLIGHTS Two cationic antimicrobial peptides (AMPs) were designed. Molecular docking of the AMPs revealed better antimicrobial activity than the reference. The novel AMPs had net positive charge and optimal hydrophobic amino acids

Prevalence of Surgical Site Infection in a Nigerian University Teaching Hospital

Surgical Site Infection (SSI) is a serious complication that limits the benefits of surgical interventions. It is a serious problem globally and particularly in Africa and other developing countries where inadequate resources and skilled personnel among others are contributing to the acquisition and spread of this infection. This study determined the prevalence of SSI and antibiotics susceptibility pattern of surgical site pathogens at a University teaching hospital in Abuja, Nigeria. Medical records of 729 and 825 patients operated and discharged in the year 2013 and 2014 respectively were examined for documentation of SSI based on Centre for Disease Control (CDC) criteria. In the year 2013 and 2014, the prevalence of SSI was found to be 15.6% and 13.58% respectively. In the two years, Staphylococcus aureus was the most prevalent pathogen causing SSI. This was followed by E. coli in 2013 and Klebsiella spp in 2014. In the two years, majority of the isolates were found to be resistant to the commonly used antibiotics in the hospital. The high SSI prevalence rate observed in this study calls for urgent review of infection control policies of the hospital

Chemical composition and antibacterial activity against multidrug-resistant uropathogenic E. coli of essential oils from the Algerian endemic Origanum glandulosum Desf.

Antibiotics are becoming ineffective against resistant bacteria. The use of essential oils (EOs) may constitute an alternative solution to fight against multidrug-resistant bacteria. This study aims to determine the chemical composition of EOs from five populations of the endemic Algerian Origanum glandulosum Desf. and to investigate their potential antibacterial activity against multidrug-resistant uropathogenic E. coli strains. The EOs were obtained by hydrodistillation and their composition was investigated by gas chromatography/mass spectrometry (GC/MS). The antibacterial activity was evaluated by the disc diffusion method against eight E. coli strains (six uropathogenic resistant and two referenced susceptible strains). Minimum inhibitory and bactericidal concentrations (MIC/MBC) were obtained by the broth microdilution method. The main EO components were thymol (15.2–56.4%), carvacrol (2.8–59.6%), γ-terpinene (9.9–21.8%) and p-cymene (8.5–13.9%). The antibacterial tests showed that all the EOs were active against all the strains, including the multidrug-resistant strains. The EO from the Bordj location, which contained the highest amount of carvacrol (59.6%), showed the highest antibacterial activity (inhibition diameters from 12 to 24.5 mm at a dilution of 1/10). To our knowledge, this is the first description of the activity of O. glandulosum EOs against resistant uropathogenic strains. Our study suggests that O. glandulosum EO could be used in some clinical situations to treat or prevent infections (e.g., urinary tract infections) with multidrug-resistant strains

Phenotypic and genotypic characterization of clinical carbapenem-resistant Enterobacteriaceae isolates from Sokoto, northwest Nigeria

Emergence and spread of carbapenemase-producing Enterobacteriaceae (CPE) are two of the major problems currently threatening global public health. In Nigeria, interest in CPE is recent. In Sokoto, northwest Nigeria, there are no data on the prevalence and mechanism underlying carbapenem resistance. In this study, we aimed to investigate the presence of clinical carbapenems-resistant Enterobacteriaceae isolates in two leading hospitals in Sokoto, northwest Nigeria. A total of 292 non-duplicate Enterobacteriaceae isolated from clinical specimens processed in the diagnostic laboratories of two hospitals between January and June 2019 were collected. Of these, 129 (44.2 %) and 19 (6.5%) were resistant to third-generation cephalosporin and carbapenems, respectively. RT-PCR revealed that 10 (7.8%), 19 (14.7%) and 46 (35.7%) of the third-generation cephalosporin-resistant isolates harboured bla(SHV), bla(TEM) and bla(CTX-M) genes, respectively. The modified Carba NP test result showed that only 7 (36.8 %) of the 19 carbapenem-resistant isolates were carbapenemase producing; among them, bla(NDM-5) and bla(OXA-181) genes were identified in five and two isolates, respectively. However, none of the carbapenemase genes investigated, including bla(VIM), bla(KPC) and bla(IMP), was detected in the remaining carbapenem-resistant isolates, suggesting a non-enzymatic mechanism. This study reports for the first time, the emergence of CPE in Sokoto state and the detection of NDM-producing Citrobacter freundii in Nigeria. The observed CPE in this study is a concern in a country where alternative antibiotics are rarely available. (C) 2020 The Authors. Published by Elsevier Ltd