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The global industrialization of chemical dyes used for household products has resulted in various dyes leaching into the soil. Azo dye textile contamination could lead to infertile soil. This study investigates the ecological effect of azo textile dye contamination on bacterial biomass, selective pressure, and associated physicochemical changes in soil samples contaminated with textile azo dye in Itoku, Abeokuta, Nigeria. Microbiological and physicochemical changes of the soil and effluent samples collected were determined using standard procedures.  Results revealed that the average count of total viable bacteria in the contaminated sampling sites ranged from 0.82±021 x 106 cfu/g to 1.65±0.02 x 106 cfu/g which was significantly lower than the control bacterial counts. The dye contaminated and the control soil samples each contained a heterogenous population of bacteria which included Paenibacillus validus, Bacillus licheniformis, Bacillus niacin, Seratia liquefaciens, Staphylococcus gallinarum, Bacillus subtilis, and Bacillus coagulans. The physicochemical analysis of the soil revealed high levels of pH in the azo dye contaminated soil (10.4–11.1) and electrical conductivity was also highest in the effluent (1250 to 2943 units) compared to the control (430 to 480).  Importantly, the control samples were higher in all of the other tested soil parameters including cation exchange, the mean value of the organic matter, water holding capacity, particle density, moisture content, and total porosity. Conclusion- Azo dye contamination caused decreases in bacterial density and many other soil parameters along with higher PH and electrical conductivity which suggests that azo textile dye contaminated soil is unfavorable for agricultural purposes and potentially toxic to the ecosystem.

This investigation was carried out to assess the bacteria associated with cocoa beans at different stages of fermentation and determine the changes in the phytochemical constituents of the fermenting beans. The pour plate technique was used for bacterial isolation while phytochemicals were assessed based on standard qualitative chemical reactions. The total bacterial count on the cocoa beans reduced during fermentation from the initial 86.2±0.02 x 105 CFU/g (day 0) to 1.00±0.00 x 105 CFU/g on day 5. However, there was an increase in the lactic acid bacteria count from 48.7±0.03 x 105 CFU/g (day 0) to 111.7±0.03 x 105 CFU/g on day 3, then reduced to 51.4±0.01 x 105 CFU/g on day 5. Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis, Lactobacillus fermentum, Lactobacillus plantarum and Lactobacillus acidophilus were isolated from the cocoa beans at different stages of the fermentation. There was a gradual increase in the temperature of the fermenting cocoa mass from the initial 25.6°C recorded at the beginning of the fermentation to 42.8°C recorded on day 5. Also, the pH of the fermenting cocoa beans reduced significantly from 6.1 at the commencement of the fermentation to 3.2 on day 5. In the total titratable acidity assay, the acidity of the cocoa beans increased from 3.12% at the beginning of the fermentation to 7.12% on day 5. Further, in the phytochemical screening, only alkaloids, phenols, steroids and flavonoids were detected in the beans throughout fermentation period whereas tannin and saponin were not found in the beans at any stage of fermentation. The preset phytochemicals got reduced in intensity as fermentation advanced. From these results, it can therefore be concluded that fermentation helps to improve the taste quality and phytochemical properties of Nigerian cocoa beans.

In this study, a maize based local snack aadun was formulated from yellow maize flour and ripe plantain blends in a bid to improve its quality. The snacks were subjected to microbial analysis using pour plate method, proximate composition, mineral content and the sensory properties of the snacks were assessed. The results indicated bacterial count ranging from 1.20 to 2.80 x 102 cfu/g. Also, there were no coliforms and enteric bacteria on the aadun samples albeit, there were more bacteria on aadun supplemented with plantain. Two bacteria and three fungi were isolated from the aadun samples, they were Bacillus subtilis, Staphylococcus aureus, Saccharomyces cerevisiae, Aspergillus niger, and Rhizopus stolonifer. The protein and carbohydrate were comparable for the samples while the higher moisture, fiber, ash and carbohydrate were recorded in plantain supplemented aadun with significant increase at a higher content of plantain. Sample C had the highest moisture (6.72%), fiber (7.62%) and ash (2.39%) content in comparison with the other samples whereas, the plain aadun had higher crude fat (32.29%) compared with the aadun containing plantain. The level of calcium and magnesium in the plain and aadun containing plantain were similar without significant differences. However, the level of potassium and phosphorus were significantly higher in aadun supplemented with plantain than in the plain aadun whereas sodium was found to be higher in plain aadun (289.20 mg) than the supplemented samples. There was no significant difference in the appearance and aroma of the plain aadun and plantain supplemented aadun. However, aadun with 50% plantain was ranked as the most preferred samples in terms of taste, texture and overall acceptability with a score of 8.41, 6.31 and 8.33 while the plain aadun had 4.52, 4.22 and 5.79 respectively for these properties. These indicate that aadun may be improved with inclusion of plantainup to 50% proportion.

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