Removal of Heavy Metals in Cassava Mill Effluents with Saccharomyces cerevisiae isolated from Palm Wine

Abstract

Nigeria is World leading producer of cassava account for 20% of global output. Rudimentary equipment is used for cassava processing into several products such as high quality cassava flour by smallholders that dominate the cassava processing sector in Nigeria. The properties of the wastewater, also called cassava mill effluents, often exceed the limit for effluents discharge onto environment (land and surface water) as specified by Federal Environmental Protection Agency. Cassava mill effluents induce toxicological effects on the environment and its associated biota such as fisheries, flora and fauna as well as humans. This study evaluated the capacity of Saccharomyces cerevisiaeisolated from palm wine to remove heavy metals in cassava mill effluents. The S. cerevisiae was identified using conventional microbiological techniques based on their cultural, morphological and physiological/biochemical characteristics. S. cerevisiae was inoculated into the sterile effluent and incubated for 15 days and triplicate sample were withdrawn at 5 days interval for analysis. The samples were prepared and analyzed using flame atomic adsorption spectrometry. Results showed a decline by 44.52%, 26.26%, 51.54%, 43.20% and 65.19% for copper, zinc, manganese, iron and nickel respectively. The findings of this study showed that S. cerevisiae is a potential microorganism for the remediation of heavy metals in cassava mill effluents.