Microbial fuel was constructed using two liter plastic transparent chambers representing the cathode and anode poles. The electrodes used were carbon and copper which were utilized in producing a carboncarbon and copper-copper fuel cells respectively. A 1% sodium chloride and 2% agar proton exchange membrane was used to connect both chambers of the fuel cells. Waste water generated from students' hostel in Federal University of Technology Owerri [FUTO], Nigeria, was used as the substrate for pitching both fuel cells. An initial voltage of 308 mV and 338 mV were recorded for both fuel cells. The voltage was monitored for 14 days. During this period a maximum of 0.81 V and 0.62 to 0.02 V were recorded for the copper-copper and carbon-carbon fuel cells, respectively. The voltage production resembled typical growth curve with the performance of the copper-copper fuel cell being better than the carbon-carbon fuel cell in consistency. When both fuel cells were connected in series, a combined voltage of 138 mV (1.38 V) was obtained indicating that arranging the cells in series yielded a maximum output. When the microbial biofilm of both electrodes were analyzed, the microbial population included both aerobic and anaerobic bacteria which included the following: Bacillus spp., Corynebacterium spp., Staphylococcus spp., Enterococcus spp. and Micrococcus spp. This research demonstrates that microorganisms have the capacity to produce electricity using domestic wastewater as substrate.

Effect of plantain (Musa paradisiaca (L) AAB genomic group) peel and stalk extracts were investigated using percentage inhibition test. Complete inhibition of growth (100%) was observed for Aspergillusniger, Aspergillus oryzae and Rhizopus stolonifer at 1.0 mg/ml concentration of stalk extract. Peel extract inhibited A. niger 100%, A. oryzae 76.67% and R. stolonifer 56.67% at the same concentration. As concentration reduces, growth inhibition reduces also up to the minimum inhibitory concentration. The results of this work justify that the plant extracts were able to inhibit and kill the growth of spoilage fungi and this implies that the extract in appropriate doses can be used in food preservation and to treat infections caused by this spoilage fungi. The results further justify the claim that Musa paradisiaca (L) stalk and peel extract demonstrated antifungal action in which methanol was seen to be a better solvent for extracting active ingredients from medicinal plants considering the high susceptibility of test organisms to methanol extract than ethanol extract used in this study. Phytochemical screening showed the presence of hydrogen cyanide, tannin, alkaloid, steroid, saponin and flavonoid. The growth inhibition of A. niger, A. oryzae and R. stolonifer by Musa paradisiaca peel and stalk methanol and ethanol extract in this study suggest the presence of antifungal substance in the plant tissue and the possibility of using the extract to control plant pathogens especially where the spoilage fungi used in this study are involved.

Detection of AmpC-mediated resistance in Gram negative organisms poses a problem due to misleading results in phenotypic tests. There are no recommended guidelines for detection of this resistance mechanism and there is a need to address this issue as much as the detection of extended spectrum beta lactamases (ESBLs) since both may co-exist and mask each other. Several methods have been used to detect the presence of AmpC β-lactamase production in some isolates but most of these methods are not reliable. There is a need for a reliable method of evaluating the presence of AmpC βlactamases in clinical isolates. A total of 81 consecutive non repetitive clinical isolates of Escherichia coli (n=40) and Klebsiella spp. (n=41) were screened for AmpC production by disc diffusion method using cefoxitin (30 µg) disc and confirmed by inhibitor based test using boronic acid as inhibitor. A total of 16 E.coli isolates (40%) and 16 Klebsiella isolates (39.02%) screened harbored AmpC enzymes, of which 43.75% of E.coli and 56.25% of Klebsiella isolates coproduced ESBL enzymes. Pure AmpC production was observed in 56.25% of E.coli and 43.75% of Klebsiella isolates. The inhibitor based test was useful in identifying cefoxitin susceptible AmpC producers and could also effectively differentiate ESBL from AmpC producing isolates.

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