The preservative potentials of sweet orange seed oil on leather products in Nigeria

Orange seed oil was extracted using the steam distillation method. The fungi isolated from the leather samples were Aspergillus niger, Aspergillus fumigatus, Aspergillus flavus, Paecilomyces sp., Penicillium sp., Rhizopus nigricans and Alternaria sp. However, the fungal species vary from person toperson. The orange seed oil was active against Paecilomyces sp., Penicillium sp. and Rhizopus nigricans at a minimum concentration of 2.0, 3.0 and 3.0%, respectively, whereas the other isolates were inhibited at higher concentrations. There was considerable reduction of the mycelia growth when3% oil extract was introduced into the medium as against growth on only Czapek’s Agar medium. There was no inhibition against Alternaria sp

Antimicrobial screening of Terminalia avicennoides and Acalypha wilkesiana

The antimicrobial activities of extracts of Terminalia avicennoides (Mexican tea) and Acalypha wilkesiana (copper leaf) were screened against Pseudomonas aeruginosa, Bacillus subtilis, Escherichia coli, Klebsiella, Salmonella typhi, Staphyloccus aureus and Candida albicans. The extracts showed a better activity against all organisms but T. avicennoides showed high activity against C. albicans. The antimicrobial activities for both plant extracts were more pronounced at a high concentration than at low concentration of the extracts. The extracts of the two plants can be used in the treatment of diseases where the test organisms are implicated.Keywords: Antimicrobial activities, Terminalia avicennoides, Acalypha wilkesian

Optimization of bio-ethanol production from cassava effluent using Saccharomyces cerevisiae

The ethanol producing capability of Saccharomyces cerevisiae from cassava waste water was enhanced. Enhancement was obtained by varying pH, culture age and nutrient supplementation during fermentation until optimum conditions were attained. Optimum fermentation duration for ethanol production in acid and enzyme hydrolysates was 24 h. The start-up fermentation experiment process with S. cerevisiae resulted in 1.47 and 1.00% (v/w) ethanol in acid and enzyme hydrolysates, respectively. Appropriate adjustment in pH however, yielded 3.60 and 1.88% (v/w) ethanol in both acid and enzyme hydrolysates of cassava waste water. The pH value that resulted in optimum ethanol production by the test isolate was 5.5. Furthermore, culture age that resulted in highest ethanol yield was 3 days old culture. Consequently, when 3 days old cultures were employed in fermentation of acid and enzyme cassava waste water hydrolysates, ethanol generated increased to 3.61 and 2.91% (v/w), respectively. The addition of NPK fertilizer, NaNO3 and K2HPO4 salts to each fermentor further enhanced the glucose utilization capacity of S. cerevisiae and concomitant ethanol generation such that ethanol produced increased to 14.5, 8.15 and 5.74 (%v/w) in acid hydrolysate containing NPK fertilizer, NaNO3 and K2HPO4 salt supplements, respectively. The corresponding ethanol yield in enzyme hydrolysates were 8.30, 5.10 and 3.00 (%v/w) respectively. All the three nutrient supplements proved suitable for enhancing the fermentative capability of S. cerevisiae in a decreasing order NPK > K2HPO < NaNO3. The results reveal that optimum combinations of pH, nutrient concentrations and cultural status play a major role in getting maximum bioconversion of cassava waste water to ethanol.Keywords: Saccharomyces cerevisae, cassava wastewater, hydrolysates, enhancement, nutrient supplemen