Production of Bio-ethanol from Molasses by Schizosaccharomyces Species
Shami E. A. Bakhiet *
Department of Microbiology and Molecular Biology, Faculty of Science and Technology, Al-Neelain University, Khartoum, Sudan.
Marwa Abdalrhim Mahmoud
Department of Microbiology and Molecular Biology, Faculty of Science and Technology, Al-Neelain University, Khartoum, Sudan.
*Author to whom correspondence should be addressed.
Abstract
Aims: The aims of this study were isolation of Schizosaccharomyces species and production of bio-ethanol from local sugarcane molasses.
Study Design: The study was designated as an experimental study.
Place and Duration of Study: This study was conducted at the Department of Microbiology and Molecular Biology, Faculty of Science and Technology, Al-Neelain University, Khartoum – Sudan “1st February to 30thMay 2014”.
Methodology: Schizosaccharomyces species were isolated from three different sources (Lentils, Banana and Sorghum Fermented dough) using poured plate technique consisting Yeast Extract Agar (YEA) medium. Physical and microbiological analyses were carried out for molasses samples. Raw Molasses (RM) in range of 100-500 ml and Sucrose-determined molasses in range of 10-50% sucrose were fermented using three isolates for each concentration separately. The bio-ethanol was determined and evaluated.
Results: The moisture content of molasses was found to be 65%. The ash was 6.50%. The pH value was decreased by one unit during the fermentation processes due to the molasses degradation with acid production. Bio-ethanol was produced from two types of molasses preparations (raw molasses and sucrose determined concentration samples). Schizosaccharomyces spp. fermented molasses samples at all concentrations except 100% because the solution was hypertonic and the microorganisms did not tolerate that concentration. The highest volume of ethanol obtained at concentration of 3:300 ml of molasses/row. While the lowest one obtained at concentration of 4:10% of sucrose / row. The final bio-ethanol was appeared to be colourless, clear, bright, and free from turbidity indicating its high specification quality.
Conclusion: The best conditions to obtain a highest volume of bio-ethanol are appropriate concentrations of molasses and suitable pH. The highest volume of bio-ethanol was 23.51 ml which obtained at 85.5 g/solids (molasses) and pH 6. While highest volume of bio-ethanol is sucrose-determined concentration sample was 16.03 ml at 71.25 g/solids and pH 6. We recommended the utilization of Schizosaccharomyces species in large scale production of ethanol to manage the industrial wastes.
Keywords: Schizosaccharomyces, molasses, bio-ethanol, biofuel, distillation, sucrose.