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Background One of the main challenges of wound healing is infection with multi-drug resistant (MDR) bacteria such as Staphylococcus aureus. The spectrum of antibiotics used to treat them is declining; thus, there is a need for alternatives. Our study was designed to evaluate the antimicrobial properties of honey, its pharmacokinetics (ADMET) properties and in-silico analysis of its bioactive compounds against dihydropteroate synthase of S. aureus using trimethoprim as control. Methods Standard protocols were employed in collection and preparation of samples, generation of canonical strings, and conduction of microbiological analyses. Bioactive compounds’ ADMET properties were evaluated using the SWISSADME and the MCULE toxicity checker tools. The MCULE one-click docking tool was used in carrying out the dockings. Results The gas chromatography-mass spectrophotometry revealed twenty (20) bioactive compounds and was dominated by sugars (> 60%). We isolated a total of 47 S. aureus isolates from the wound samples. At lower concentrations, resistance to trimethoprim (95.74 to 100.00%) was higher than honey (70.21 to 96.36%). Only seven (7) isolates meet Lipinski’s rule of five and ADMET properties. The docking scores of the bioactive compounds ranged from -3.3 to -4.6 while that of trimethoprim was -6.1, indicating better binding or interaction with the dihydropteroate synthase. The bioactive compounds were not substrates to P450 cytochrome enzymes (CYP1A2, CYP2CI9 and CYP2D6) and p-glycoprotein, indicating better gastrointestinal tract (GIT) absorption. Conclusion The favourable docking properties shown by the bioactive compounds suggest they could be lead compounds for newer antimetabolites for management of MDR S. aureus.

Background Potable water have been shown to be a source of contamination due to poor handling during its supply chain process. It is common practice for sachet water, a widely consumed potable water across Nigerian and West African cities to be exposed to sunlight for hours daily before they are sold to consumers. This practice coupled with the polyethene plastic packaging could cause leaching of heavy metals and other chemical components of the plastic package into the sachet water, and also cause its biological quality to deteriorate posing great public health concerns which prompted this study. Methods Three (3) sachet water brands (n = 4 per brand) were collected and exposed to sunlight daily for 14, 28, and 48 days were analyzed for heavy metals, total hardness, and other physico-chemical parameters using standard protocols. In addition, we also evaluated total heterotrophic bacteria and coliform counts, and antibiotic susceptibility of resulting isolates. Results All brands of the exposed sachet water recorded increased levels of physico-chemical parameters (except pH) and heavy metals compared to the control group in a linear fashion to exposure time. Zn was the most ingested from sachet water brands. The ADD, HQ, and HI evaluations revealed that consuming these brands of sachet water exposed to different durations of sunlight could be expose consumers to Cr, Cd, Pb, As, and Ni toxicities. The CR of Cr, As, and Ni in all brands of the sachet water exposed to sunlight were above the safe value of 10− 4, indicating a likelihood of the population having cancer after over 60 years of exposure. Ni posed the highest carcinogenic risk in all sachet water brands exposed to sunlight for 42 days. All the brands evaluated failed to meet the World Health Organization and national safety limits for total heterotrophic bacteria and total coliform counts. Six out nine isolates elaborated extracellular amylase while all produced protease, enzymes linked with biofilm formation and pathogenicity, respectively. Furthermore, the isolates showed multi-drug resistance. Conclusion The potential health risk inherent in this practice has significant public health implications for the consumers across Nigeria and the West African region.

Nigeria's most consumed potable water plastic wastes are indiscriminately dumped into agricultural soil despite their ability to become microplastics. The study evaluates the potential impacts of these microplastics on soil physico-chemical parameters, soil bacterial diversity and functions as well as antibiotic resistance. Soil sample was collected using a sterile hand-held auger and its physico-chemical parameters evaluated. Baseline microplastic concentration was determined via the flotation method while microbial isolates were obtained from the test (enriched with microplastics) and control samples using cultural technique and metagenomics. Metagenomic next-generation sequencing (mNGS) was done using the Illumina Miseq platform. The cluster of orthologous genes (COG) tool was used in the prediction of bacterial functional roles. Replicate readings were analysed using analysis of variance (ANOVA) and means compared using the student’s t test. Observed baseline microplastic concentration was 0.08 particles/g of soil. The addition of the microplastics to the soil sample decreased the concentrations of some metals (iron, zinc, lead and nickel) while cobalt concentration, pH level and microbial counts increased. Microbial count and pH clustered together while iron, magnesium, nitrate, nitrite, chromium, cobalt, total organic carbon, zinc, lead, and nickel showed positive loading values suggesting that the addition of microplastics could alter them. Dominant taxa were proteobacteria, unknown, firmicutes at the phyla level. At the level of species, Pseudomonas species dominated microplastics incubated soil while potential pathogenic species such as Klebsiella dominated the control sample. A higher level of multi-drug resistance and altered metabolisms was observed in the test sample. Sachet water microplastics could have serious implications for public health and food security.

Background Staphylococcus aureus has prevailed against the majority of antibiotics currently in clinical use, making it a significant global public health problem. As a safer alternative, bioactive compounds have been explored. Annona muricata has been shown to possess antimicrobial activity. However, there are few reports on the molecular activity of A. muricata bioactive compounds against S. aureus. Thus, this study was aimed at evaluating the antimicrobial activity of its crude extract as well as investigating the potential of its bioactive compounds against the Cap5O capsular polysaccharides (CPS) of S. aureus via molecular docking. Methods Collection of plant leaves, preparation of extracts, anti-nutrient analysis, phytochemical screening via crude method and gas chromatography-mass spectrophotometer (GC-MS), isolation and characterization of S. aureus and the antimicrobial activity test were all done using standard protocols. Molecular docking was done using the MCULE online tool with emphasis on docking scores, toxicity, and other properties. Results Crude screening of the extracts showed the presence of polyphenols, hydroxyanthraquinones, reducing compounds, flavonoids, saponins, glycosides, alkaloids, anthraquinones, phlobatannins and tannins in different concentrations. Anti-nutrient analysis showed the presence of allowable levels of evaluated anti-nutrients. GC-MS revealed a total of twenty-nine (29) bioactive compounds, out of which only 4 (13.80%) docked without toxicity and these were bicyclo[4.1.0]heptan-2-one 6-methyl, trichloromethane, carbonic acid 2-dimethylaminoethyl propyl ester, and 1-methyl-4-phenyl-5-thioxo-1,2,4-triazolidin-3-one on either the NAD-binding or C-terminal substrate binding domain of Cap5O. Conclusion Results obtained show that Cap5O could be a potential drug target for multi-drug resistant S. aureus, however, further studies aimed at evaluating these bioactive compounds individually and in combination are highly needed.