Effect of Temperature on Sulphate Removal from Wastewater by Selected Bacterial and Fungal Species

The aim of this study was to investigate the effect of temperature on sulphate removal from wastewater by selected bacterial (Pseudomonas spp., Klebsiella spp., Staphylococcus spp. and Lysinibacillus spp.) and fungal (Aspergillus niger, Aspergillus flavus, Fusarium spp. and Absidia spp.) isolates. The study was carried out under shake flasks conditions at incubation temperatures of 30ºC, 35ºC, 40ºC and 45ºC at shaking speed of 150 rpm. After inoculation with the respective isolates, aliquot wastewater samples were aseptically removed from each flask prior inoculation and every 24 h, for 96 h for the estimation of sulphate levels in the wastewater and pH, using standard procedures. The results revealed optimum temperatures for sulphate removal to range from 30ºC -35ºC and 30ºC – 40ºC, for the bacterial and fungal isolates, respectively. Also observed was a consistent increase in pH of the wastewater throughout the period of incubation. This trend was irrespective of the test microbial isolates and the incubation temperature. The study was able to reveal the role of temperature in sulphate removal ability of the test isolates under the experimental conditions used for investigation.