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Bioflocculants of microbial origin have the advantage of being safe, biodegradable and harmless to the environment. Production of bioflocculant by two fungi isolates and the factors affecting its production were investigated in this study. Primary screening of fungi for the production of bioflocculants, efficiencies and conditions for the optimum production of the bioflocculants were determined using standard microbiological and chemical methods. Aspergillus flavus MCB 271 and Aspergillus niger MCBF 08 were the best bioflocculant producers among the fourteen fungal isolates screened. Aspergillus flavus optimally produced bioflocculant with glucose and peptone as sole carbon and nitrogen sources respectively. Calcium ions (Ca2+) at 78.4% served as best cation sources for bioflocculant production with optimal pH of 7 and temperature of 40°C. Aspergillus niger MCBF 08 produced bioflocculant optimally when the media had peptone as a nitrogen source and maltose as a sole carbon source. The two species achieved the maximum flocculating activity of            97% (A. flavus MCBF 271) and 86% (A. niger MCBF 08) at pH values of 7 on the 3rd day of the study and caused a reduction in bacterial load of the wastewater samples by 58.73% and 60.85% respectively. These bioflocculants are thus potential replacement for synthetic flocculants conventionally used for wastewater treatment.

Microbial and physicochemical properties of seven branded, seal tampered refrigerated fruit juices were carried out in this study using standard methods. Coliform counts ranged from 2.079 to3.093 log 10 cfu/ml over the storage period with pineapple juice and citrus juice having the highest and least coliform count respectively. Total bacteria count in the juice ranged from 7.009 to 8.243 log 10 cfu/ml. Citrus fruit juice however had the highest staphylococcal count while pineapple juice had the least (2.344 to 3.881log 10 cfu/ml). Also, osmophilic yeast count ranged from 2.017 to 3.903log 10 cfu/ml, having the highest load in orange fruit juice and lowest load in citrus fruit juice. The pH of the juice samples ranged from 2.9 to 4.2 during the period of refrigeration. Conductivity was highest in apple fruit juice and lowest in orange nectar pulp fruit juice. The total dissolved solids ranged from 0.29 to 1.95 over storage and was recorded highest in apple juice and lowest in orange nectar pulp fruit juice. Turbidity ranged from 5.8-200. These results indicate a reduction in the quality of fruit juices after 5 days of opening and thus reveals that both spoilage and pathogenic organisms could proliferate in juices despite refrigeration.

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