Rapid industrialization and growing population result to high demand for energy. Depletion and rise in price of petroleum as well as environmental pollution necessitates the need for alternative source of fuel, hence bioethanol production. Rice bran (Oryza sativa), Corn bran (Zea mays) and Sorghum bran (Sorghum guinense) and saw dusts of Khaya senegalensis (Red wood), Terminalia superba (Black wood), Gmelina arborea (White wood), were used for the study. The yeasts used for the study were isolated from fermented beverages (Sorghum beer, Millet beverage and Palm wine). The results of the lignocellulosic biomass of white saw dust, red saw dust, black saw dust, rice bran, corn bran and sorghum bran revealed cellulose components as 77.78%, 75.55%, 68.59%, 64.83%, 54.82% and 55.14% respectively. A total of 25 yeasts were isolates and identified using API 20C AUX strip. The yeast isolates, K2, B5, B7 and P1 had the highest ethanol tolerance value of 14%. The results showed that the ethanol-producing ability of the yeast isolates ranged from 4.1% to 10.3%. Fourier Transform Infrared Spectrophotometer (FTIR) and Gas Chromatography and Mass Spectrometry (GC-MS) analyses showed that ethanol is the main compound produced by yeasts from the lignocellulosic materials. This study revealed that Saccharomyces cerevisiae isolated from palm wine (P1) is best in ethanol production and tolerance, and this high prolific strain can be exploited or engineered for ethanol production. Therefore, Lignocellulosic biomasses are recommended as raw materials for producing ethanol, which is a promising alternative energy source as against the depleting petroleum.

Pulp waste water, soil from agricultural waste dump site and rotten wood were investigated for the presence of fungi with cellulolysic ability. Fungi Isolates obtained from the samples were identified based on cultural and morphological characteristics. Seven species of fungi namely, Aspergillus niger, Rhizopus oryzea and Fusarium from soil, Penicillium notatum, Mucor resmosus and Aureobasidium sp from rotten wood, Trichoderma citrinoviride, Fusarium salani, A niger and P notatum from pulp waste water were isolated. Among the seven fungi species , A. niger, F. salani, and P. notatum recorded the highest frequency of occurrence, (2), while T. citrinoviride, R. oryzea, Aureobassidium sp recorded frequency occurrence of one (1)each and the cellulytic activity was determined by the ratio of zone of clearing and colony diameter. The difference in zone of clearing produced by the fungi isolates (A. niger, T. citrinoviride, F. salani), on CMC containing plate were not significantly different at (p˂ 0.05). Highest cellulase activity ratio was exhibited by T. citrinoviride (1.39), followed by A. niger from soil (1.30).This result highlights the potential of T citrinoviride as strain for industrial production of cellulolysic enzyme.

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This study investigated the effects of Saccharomyces cerevisiae-induced fermentation on the antioxidant properties of Roselle calyx aqueous extract and determined the physicochemical changes of the fermented extract. Total phenolics, total flavonoid, ascorbic acid content, total monomeric anthocyanin content and DPPH radical scavenging activity of roselle aqueous extract were investigated before and after fermentation. Roselle calyx aqueous extract was fermented for period of 10 days. During fermentation, the extract was evaluated for pH, alcohol (%), titratable acidity (%) and total soluble solids (oBrix). Total soluble solids and pH significantly decreased at the end of the fermentation whereas titratable acidity and alcohol content significantly increased. Fermentation caused significant reduction in total monomeric anthocyanin content from an initial value of 3518±30.8 to 1075±28.2 CGE/100 g dry extract whereas significant increase was observed in total phenolic content from 195.75±76.01 to 455.5±1.41 mgGAE/100 g dry extract and ascorbic acid content from 1392±101 to 2028±108 mg AAE/100 g dry extract and total flavonoids increased from 193.0±74.25 to 291.5±4.95 mgQE/100 g dry extract but it was not significant. There was also a significant increase in 1-1-diphenyl-2-picryl hydrazyl (DPPH) scavenging activity of roselle calyx aqueous extract from an initial value of 44.15% to final value of 71.10% after fermentation, leading to an increase in antioxidant activity. Therefore, the quantity of phenolic compounds increased with fermentation process. This study showed that roselle calyx aqueous extract fermented by Saccharomyces cerevisiae has a better antioxidant activity.

Microorganisms such as fungi can fragment carbon compounds by hydrolytic enzymes. The filamentous fungus, Aspergillus niger is now mostly considered because of its ubiquitous nature, non-fastidious nutritional requirements and it is classified generally as safe. This study was aimed at the production of cellulosic enzymes by A. niger and hydrolytic degradation of cellulosic materials by these enzymes. Standard methods were employed in soil samples collection, isolation of A. niger from the soils and their screening for enzyme production. Results showed that the A. niger isolates exhibited considerable activities of degrading and hydrolyzing cellulose in the agar media. The highest FPase, cellulase and xylanase activities were obtained from white saw dust with concentrations of 0.4059 U/ml, 0.7695U/ml and 1.3488 U/ml respectively. Also, results showed high enzyme activity at pH 6 (0.52U/ml) and temperature of 30ºC (0.72U/ml). Acid hydrolysis of the cellulosic substrates resulted to the release of 6.5% total sugar from white sawdust. The findings of this study revealed that the enzymes produced by A. niger hydrolyzed cellulosic materials but acid is more efficient than the enzymes in the hydrolysis and release of total sugar from cellulosic materials. This study recommends that cellulolytic enzymes used in the industries should be produced locally using filamentous fungus such as Aspergillus niger and cellulosic materials as carbon source.