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In this study the microbiota of Clarias gariepinus tissues harvested from e-waste-soil polluted vials were assessed. Soil samples contaminated with e-waste were analyzed using standard analytical protocol while the microbial study was obtained using standard conventional microbiological techniques. The results revealed that the soil was sandy-loamy and blackish in colour. High organic matter (17.60%) and organic carbon (10.17%) were obtained. Also, higher calcium (182.00 mg/kg) and phosphorus (146.65 mg/kg) contents compared to other mineral constituents were recorded while, the heavy metals ranged from 0.32-64.90 mg/kg. Bacterial count ranged from 9.0 × 102 to 4.0 × 103 cfu/L while the fungal count from 4.0 × 102 to 2.3 ×103 sfu/L. The genera of bacteria isolate were identified as Staphylococcus, Proteus, Bacillus, Listeria, Salmonella, Enterobacter, Pseudomonas, Lactobacillus and Corynebacterium and fungal isolates were Penicilliun, Candida, Articulospora, Aspergillus, Rhizopus, Mucor, Zoopage, Varcosporium and Rhodotorula. Microbial species richness of fish tissues from polluted vials indicates a more poly-diverse microbial community compared to those from unpolluted vial. Differences were observed in the occurrence of fungi on the surfaces of catfish tissues in control vial compare to those on fishes from polluted vials. Hence, there is a need for proper water management for fish culturing and caution in the exploration of fishes from polluted natural waters for human consumption.

The study was carried out to determine the microbial and physicochemical identify the bacteria and fungi associated with the fermentation of African Locust Bean (Parkia biglobosa) "Iru" effluent and to assess the biocidal effect of fermented Parkia biglobosa effluent on some selected insects (mosquito, bean and rice weevils). The physicochemical properties of the fermented locust bean effluents were assessed. The results obtained on the effluent physicochemical parameters showed that there were differences between the control effluent and the fermented African locust bean effluent from the laboratory. Specifically, total hardness (614.00-194.00 mg/l), total dissolved solids (102.15-108.53 mg/l), total solids (125.30-131.50mg/l), the total alkalinity (762.50-688.75 mg/l) and the total acidity (as CaCO 3) (206.70-263.40 mg/l). The minerals of the two effluents showed sharp differences in the sodium, potassium, calcium and magnesium composition. Control effluent was higher than the test effluent in sodium (1578.19 mg/l), potassium (4734.19 mg/l) and magnesium (4304.16 mg/l) while the test effluent was only higher in calcium (7259.53 mg/l) compared to that of the control. The microbial types in fermented samples were identified after the fermentation period of 72 hrs. The bacterial profile were Bacillus subtilis, Bacillus cereus, Proteus mirabilis, Staphylococcus aureus, Leuconostoc mesenteroides, Escherchia coli and Enterococcus faecalis. Leuconostoc mesenteroides and Bacillus subtilis had the highest occurrences. The fungi isolates were Fusarium sp., Saccharomyces cerevisiae, Aspergillus fumigatus, Aspergilus niger and Penicillium sp. Evaluation of the effect of fermented African locust bean effluent on bean weevil Callosobruchus maculatus (F.) with respect to insect mortality showed considerable biopesticidal potential on the bean weevil. The results revealed that the fermented locust bean effluent had the highest mortality of six after 20 minutes and the lowest mortality of one after 40 minutes. With further research, fermented African locust bean effluent can be used as biopesticide which would be cheaper, less hazardous to human health and easily accessible to local people to preserve cowpea produce.

This study was designed to investigate the possible variation in bioaccumulation of heavy metals (lead, cadmium, zinc, cobalt, chromium, nickel, and manganese) in the tissue of harvested Oreochromis niloticus (tilapia) and the associated fungi from vials treated with soil from e-waste dumpsite and soil without e-waste. E-waste is electronic waste which contains valuable metals as well as potential environmental contaminants. The heavy metals in soil and fish samples were determined using flame atomic absorption spectrophotometer (AAS) after homogeneity and digestion of samples. The associated fungi were identified using standard microbiological methods. The genera of the associated fungi were: Penicillium, Candida, Articulospora, Aspergillus, Aspergillus, Aspergillus, Rhizopus, Mucor, Zoopage, Varicosporium and Rhodoturula. The quantity of fungi isolated from each pollution treatments showed that the number of fungi were inversely proportional to the quantity of e-waste soil pollution and directly proportional to the quantity of soil without e-waste pollution. The occurrence of the fungi species revealed that the untreated (control) vial had the highest occurrence (191) while the lowest occurrence (103) occurred in the vial polluted with the highest quantity of soil from e-waste dumpsite. The pH and the biochemical oxygen demand (BOD) of the vials were significantly affected by the pollutions. Variations were also observed in the bioaccumulation of the heavy metals by Oreochromis niloticus. Cadmium (0.01 mg/kg) and nickel (0.02 -0.08 mg/kg) were the least recorded metal in the tissue of the fish while cobalt was not detected after the five weeks period. The sequence of the heavy metals concentrations in Oreochromis niloticus tissue samples was Zn > Mn > Pb > Cr > Ni > Cd > Co. The accumulation of the metals in the fish tissue were, however, lower than the international maximum guidelines, except for manganese (0.29 -3.13 mg/kg) that exceeded the 0.01 -0.05 mg/kg threshold levels for manganese by Federal Environmental Protection Agency (FEPA). Protecting the environments from toxic metals is necessary, hence a need for public awareness on the dangers of these toxic metals and law for proper disposal of e-waste.A. I. Sanusi 556

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