Background: Automobile repair workshops contribute immensely to the generation of soil and water contamination. This study was conducted to compare the soil microbial load, heavy metals, and consequent toxicological effects, in three (3) automobile mechanic sites. Method: Soil samples were randomly collected from 3 different auto mechanic workshop in Abeokuta town of Ogun-State, Nigeria. Bacterial and fungal counts were done via standard procedures. High-performance liquid chromatography was employed for the aflatoxin quantification. Also, 24 Wistar rats were divided into 4 groups (n = 6), group 1—Control animals: orally administered distilled water, Group 2—administered soil sample solution from Ita Oshin mechanic site (I M), Group 3—administered soil sample solution from Ajebo mechanic site (A M), while Group 4—administered soil sample solution from Laderin mechanic site (L M), for two (2) weeks. Conventional methods were used to determine some physical and biochemical parameters in the rat’s serum and tissues. Results: Eight bacterial and fungal genera were identified from the soil samples with Bacillus subtilis and Aspergillus niger occurring most frequently. The levels of heavy metals (lead, zinc, chromium, and cadmium) analyzed were higher than the WHO permissible heavy metal limits in all samples. The activity of liver function enzymes ALP, AST, and ALT was significantly increased in the serum of animals exposed to the 3 soil solution samples when compared with the control group, with the highest recorded at Site II. Conclusion: High level of heavy metals and aflatoxins could predispose to several health-related hazards when humans are exposed to contaminated soil solutions around and within automobile mechanic areas.

This present study was conducted to investigate the efficacy of the essential oils (EO) of Cymbopogon citratus (DC.) Stapf. (Lemon grass) and Zingiber officinale Roscoe (ginger) against bacteria associated with otitis media (OM) in children. Ear swab samples were collected from 12 children diagnosed with OM between the ages of 0 – 5 years. Essential oils were extracted from the plants using the hydro-distillation method. The antibacterial activity of the essential oils was determined using the agar well diffusion method against isolated bacteria including Proteus mirabilis, Staphylococcus aureus, Pseudomonas aeruginosa, Proteus vulgaris, Moraxella catarrhalis, Klebsiella pneumoniae and Staphylococccus epidermidis. The antibiotic susceptibility patterns of the bacteria isolated was determined using 10 standard antibiotics as control. Greater zones of inhibition were observed in essential oil of Lemon grass as compared to Ginger. Minimum inhibitory concentrations (MIC) and Minimum Bactericidal concentrations (MBC) were carried out for each essential oil where higher values (12.5 -100%v/v) were recorded for ginger essential oil than lemon grass (0.78 – 1.56%v/v). Phytochemical analysis of the EOs of ginger and lemon grass carried out using GC-MS showed the presence of zingiberene (26.85%) and generaldehyde (21.13%) respectively as the most abundant phytocompounds. In silico study was carried out through the molecular docking method using the AutoDock version 2.1 by taking two proteins- osmoporin and mevalonate synthetase as targets and different phytocompounds from the essential oils as ligands. Molecular docking highlighted the potential of several phytocompounds in the essential oils to inhibit protein targets required by bacteria for survival.

The deleterious effects of aflatoxin-producing moulds cannot be over-emphasized in traditionally fermented food condiments like 'Ogiri' (melon paste), irrespective of their nutritional properties. Therefore, the use of essential oils as a biocontrol agent to control aflatoxin- producing moulds in food condiments like 'Ogiri' is a potential approach worth exploring. This study aimed to evaluate the antifungal properties of African Star Apple Oil and Cucumber Oil against aflatoxin-producing moulds. A total number of five samples of the ogiri (melon paste) were purchased from five different markets (Ijebu Igbo, Ijebu Awa, Ago-Iwoye, Kuto, and Osiele) in Ogun State, Nigeria. Fungal isolation and identification were carried out on the melon pastes using standard microbiological procedures. Aflatoxigenicity screening of the suspected fungal isolates was carried out using Neutral Red Dessicated Coconut Agar and viewed under an ultra-violet (UV) spectrophotometer at 365nm. The phytochemical properties and the anti-fungal potentials of the oils on the aflatoxin-producing moulds were determined using Gas Chromatography-Mass Spectrometry (GCMS) and disc well diffusion method respectively. Aspergillus flavus, Aspergillus niger, Neurospora spp., and Saccharomyces cerevisiae were the fungi isolated from the ogiri samples, with Aspergillus flavus, Saccharomyces cerevisiae and Neurospora spp. having the least percentage occurrence of 21.0%, 16.0%, and 5.0% respectively while Aspergillus niger had the highest percentage occurrence of 58.0%. The screening for aflatoxin-producing potential among the isolates indicated that only the melon samples from Osiele exhibited positive aflatoxigenicity. The result showed that fermented melon paste were highly contaminated with aflatoxigenic fungi and its consumption could pose aflatoxicosis risk to man. The antifungal efficacy of African star apple and cucumber oil against aflatoxin-producing mould displayed minimal zones of inhibition around the well, signifying limited antimicrobial activity of the oils.