Burukutu is a traditional African alcoholic beverage produced by spontaneous fermentation of malted red or white sorghum. Its unstandardised production often results in variability in microbial composition and product quality. This study investigated the microbial and fermentation profiles of burukutu prepared from both sorghum varieties, with emphasis on yeast population dynamics and acidification patterns. Laboratory-scale fermentation and analyses of locally brewed samples were conducted, with pH monitored over 48 hours. Yeasts were isolated and identified using morphological and microscopic features, alongside carbon assimilation profiles via the API 20C AUX system. Fermentation was characterised by a progressive decline in pH, confirming active microbial metabolism. Seven yeast species were identified: Saccharomyces carlsbergensis, Schizosaccharomyces pombe, Saccharomyces cerevisiae, Candida tropicalis, Candida auringiensis, Candida krusei, and Candida utilis. Among these, S. cerevisiae was predominant (36% of isolates), particularly in traditional samples. Its broad sugar assimilation and strong fermentative capacity underscore its central role in burukutu production. The dominant genera were Saccharomyces and Candida, consistent across both red and white sorghum fermentations. Comparative analysis revealed similar microbial and acidification profiles for the two sorghum varieties, indicating their equal suitability as raw materials. Notably, laboratory-prepared burukutu displayed more consistent yeast populations, suggesting that improved hygienic practices can enhance product quality and reduce microbial variability compared to traditional brewing.Overall, this study highlights the microbial ecology of burukutu fermentation, confirming the predominance of S. cerevisiae and underscoring the potential for process standardisation to improve quality and reproducibility in this indigenous beverage.
As a possible substitute for synthetic insecticides, ethanolic extract of Gliricidia sepium seeds was used as a biopesticide to test its insecticidal activity against the infestation of Callosobruchus maculatus and Sitophilus zeamais in stored cowpea and maize. Four concentrations (0.1, 0.2, 0.3 and 0.4 mL of seed extract/200 g cowpea and maize) were employed in laboratory bioassays with cypermethrin as a standard check, to evaluate contact toxicity to adults, adult emergence and seed viability. Untreated grains were set up as a negative control. Treatments were in triplicate, and all experimental data were analysed using SPSS. Results showed the efficacy of gliricidia seed extract was dose-dependent. Adult S. zeamais and C. maculatus mortality increased with higher concentrations of the extract and more prolonged exposure periods. Gliricidia extract (0.4 mL/200 g) caused 75% mortality to C. maculatus 48 hours (2 days) after application, which was significantly different (p<0.05) from the 100% mortality caused by cypermethrin at the same period. Also, gliricidia extract (0.4 mL/200 g) caused 78.3% mortality to S. zeamais, significantly different from the 100% mortality caused by cypermethrin at 48 hours. Gliricidia extracts at concentrations 0.3 mL and 0.4 mL/200 g cowpea (37.0 % and 24.33% respectively) were better than the control 56.33% in reducing the number of emerged adult C. maculatus while extracts at concentrations 0.3 mL and 0.4 mL/200 g maize (22.33% and 27.67% respectively) were more effective than the control 64.3% in reducing the number of emerged adult S. seamais. The mean percentage germination of the cowpea and maize seeds in each treatment did not vary significantly (p > 0.05). The efficacy of this plant extract serves as scientific evidence to argue for employing the gliricidia extract as a botanical substitute for synthetic insecticides, which stakeholders commonly use to protect grains stored after harvest.