International Research Journal of Microbiology (IRJM) (ISSN: 2141-5463) Vol. 2(10) pp. 393-398, November 2011 Available online http://www.interesjournals.org/IRJM Copyright © 2011 International Research Journals Full Length Research Paper Analysis of the suitability of yam, potato and cassava root peels for bioethanol production using Saccharomyces cerevisae Akponah, E. And Akpomie, O.O. Delta State University, Abraka, Nigeria. Accepted 01 November, 2011 The feasibility of bio-ethanol production from yam, potato and cassava root peels was investigated. Slurry of each peel was saccharified using acid, commercially available α- amylase and Aspergillus niger which was screened and certified for amylase production. Subsequent fermentation by Saccharomyces cerevisiae followed at room temperature for 72 hours. Composition analysis revealed that yam, potato and cassava root peels contained 46, 96 and 114.5 (mg/g) starch respectively. Glucose yield obtained after hydrolysis of yam peels using amylolytic fungi, enzyme and acid were 51.6, 48.7 and 78.1 (mg/g) respectively. Similarly, glucose levels of the respective potato peel hydrolysates were 160.8, 90.7 and 248.3 (mg/g). Saccharification of cassava root peels resulted into glucose concentrations of 210.4 mg/g, 110.4 mg/g and 250.0mg/g in amylolytic fungi, enzyme, and acid hydrolysates respectively. The ethanol yield after fermentation of yam peels hydrolysed using amylolytic fungi, enzyme and acid were 1.68, 0.56 and2.7 (%v/w) respectively. Ethanol yield from potato peels were 4.02%v/w (amylolytic fungi hydrolysate), 1.94% v/w (enzyme hydrolysate) and 9.38% v/w (acid hydrolysate). Fermentation of the respective cassava peel hydrolysates resulted in 10.5%v/w, 4.07% v/w and 17.52% v/w ethanol. Results obtained suggested that increasing the fermentation duration did not result in a corresponding increase in ethanol production hence maximum ethanol yield in various hydrolysates was at the 24 th hour of fermentation following the order acid hydrolysates > amylolytic fungi hydrolysates > enzyme hydrolysates. Also, in terms of substrate yield, highest ethanol production was from cassava root peels, followed by potato peels while yam peels yielded the least ethanol concentration. This research therefore, indicates that these peels could serve as cheap sources of glucose which can be fermented locally for bio-ethanol production especially in areas where they are in abundance. Keywords: Amylase, Hydrolysates, Bio-ethanol, Saccharomyces cerevisae and Yam Potato and Cassava peels. INTRODUCTION There is an increasing demand for ethanol production through fermentation processes all over the globe as oil reserves are dwindling and prices are soaring (Brooks, 2008). The high prices have led to energy crises in both developing and developed countries that are oil dependent. According to Naylor et al., 2007, “biofuels will remain a critical energy development target in many parts of the world if petroleum prices exceed US $ 55 – 60 per barrel.” *Corresponding author E-mail: bunmakp@yahoo.com At the global level, Brazil has been the world leading producer of biofuel and recently, Nigeria joined the league of biofuel users with the aim of generating wealth (Aisien et al., 2010). The design had generally been production from sugarcane and cassava. Klass (1998) categorized cassava alongside with sweet potato and yam as main starches that serve as staple foods for people through the world’s hot and humid regions. These plants are so proficient at supplying essential calories that they are considered the quintessential subsistent crops. However, the success of these starch crops as staple foods limits their potential development and general economic growth, for instance, cassava which