Changes in catalase activities during malting of some improved Nigerian sorghum grain varieties

The catalase activities of ten germinating improved sorghum varieties were monitored over a 4-day period to determine the effect of malting on them. This was done using standard methods that involved catalase assay at the appropriate experimental intervals. Results obtained showed that the different varieties of sorghum differed in their expression of catalase, a difference that was also reflected across the different stages of the malting process. The highest overall catalase activity (20.54 ± 0.74 U) was given by variety SK5912 after 72 hours of germination followed in second place by that from variety Nafelen (18.65 ± 0.99 U) obtained after steeping. The third and fourth highest value (17.88 ± 1.24 U and 17.08 ± 1.64 U) were given by KSV8 and Boboje after 72 and 48 hours of germination respectively. These values are probably indications that no single stage of malting was best for catalase expression among all the varieties. However, the fact that most of them (varieties ICSV 400, SK5912 and KSV 8, CSRO2 and ICSV III) all expressed their highest catalase activities after 72 hours of germination showed that 72 hours is probably the best germination stage for the elicitation of catalase among sorghum grains. The next best stage should be after 48 hours during which point three varieties (Boboje, NRL 3 and KAT 487) had their highest catalase activities. As a unity, all the sorghum varieties had their lowest catalase expression after 24 hours of germination, followed by those obtained after 96 hours germination.Keywords: catalase, sorghum, malting, peroxidase, cereal enzyme

Application of photosynthetic microalgae as efficient pH bio-stabilizers and bio-purifiers in sustainable aquaculture of Clarias gariepinus (African catfish) fry

Chlorella lewinii LC172265 and Scenedesmus dimorphus NIES-93 were grown with BG-11 medium and then transferred to fish seedlings' farm and the effects on changes in the pH, nitrite, total ammonia nitrogen and toxic ammonia were studied. Inoculation of the ponds with C. lewinii, S. dimorphus and the combined culture of C. lewinii and S. dimorphus significantly reduced the rise in the pH of the ponds (p<0.05). With these three cultures, the pond pH increased from 6.3±0.03 to only 6.5±0.2, 6.7±0.6 and 6.4±0.1 respectively within a period of 240 hours, as against control pond's pH which increased from 6.3±0.03 to 9.0±0.1 within the same period. Furthermore, inoculation with S. dimorphus reduced the nitrite concentration in the ponds to zero on the 144th hour and the concentration remained zero throughout the experiment. This was closely followed by the combined culture of C. lewinii and S. dimorphus which reduced the nitrite concentration to zero at 240th hour while C. lewinii was the least in nitrite removal. Toxic ammonia was also zeroed by the combined culture of C. lewinii and S. dimorphus at 144th hour of experiment which was followed by C. lewinii (at 192nd hour). Aquaculture ponds co-cultured with microalgae witnessed a maximum fry death rate of 40% which was much lower than 80% death rate observed in the control ponds. These results show that C. lewinii and S. dimorphus are very efficient in sustaining the quality of aquaculture water, and thus prolonging the length of time water can be used before changing.Keywords: nitrogen removal, ammonia, nitrite, fishery, fish pon

A Brief Review: Saccharomyces cerevisiae Biodiversity Potential and Promising Cell Factories for Exploitation in Biotechnology and Industry Processes – West African Natural Yeasts Contribution

Saccharomyces cerevisiae has been widely applied in the production of both industrial and indigenous/or local alcoholic and non-alcoholic beverages and includes wines, whiskies, gins, and distinct beers. In both small-scale and large-scale industrial production processes, the yeast used is a domesticated version of the organism. The production processes involving domesticated or undomesticated yeast notwithstanding, is one of the most amazing discoveries around the world. Africa, in general, and West Africa in particular have contributed to this amazing discovery involving the application of its local yeast in the food and beverage industry. In the continents of Asia, Europe, and America, the use of yeast strains for both small-scale and large-scale production processes is well documented and most of the yeasts used in major industrial processes originate from the continents of Asia, Europe, and America. Adequate information or documentation on the use of yeast originating and/or traced back to Africa for industrial production application is very scant as such remains an untapped market requiring extensive investigation. This review highlights the potential of yeast strains from West Africa and the diverse properties they possess for consideration of their use to improve the biotechnology industrial applications