The production of glucose used in ethanol production through an enzymatic hydrolysis of rice mill by Aspergillus niger
Subject Areas : Microbial Biotechnology
Masoud Hatamimanesh
1
(M.Sc., Department of Environment, Faculty of Natural Source and Marine Science, Tarbiat Modares University, Noor, Iran.)
Habibollah Younesi
2
(Associate Professor, Department of Environment, Faculty of Natural Source, Tarbiat Modares University, Noor, Iran.)
Nader Bahramifar
3
(Assistant Professor, Department of Environment, Faculty of Natural Source, Tarbiat Modares University, Noor, Iran.)
Keywords: Saccharomyces cerevisiae, Ethanol, Rice mill, Enzymatic hydrolysis,
Abstract :
Background & Objectives: Rice mill is one of the mostabundant effluent waste waters worldwide. Due to the high starch and organic compound content, it can be used as alternatives source for ethanol production as an environmental sustainable biofuel. This study was aimed to examine the ethanol production through enzymatic hydrolysis of rice mill and fermentation process by using Aspergillus niger and Saccharomyces cerevisiae yeast. Materials & Methods: In order to optimize the enzymatic hydrolysis process by A. niger, an analysis was performed to determine the effects of different concentrations of effluent with initial starch concentrations (20, 40, 50, 60and80 gl-1) and nitrogen source (NH4NO3, NH4SO4 and NH4CL). The levels of sugar and the produced ethanol were determined by DNS and gas chromatography, respectively. Results: The results showed that the effluents containing a starch concentration of 60gl-1 and (NH4 SO4) had the highest influence on glucose production, 32.27 and 31.84 gl-1 respectively. Also the results of ethanol production through hydrolysis of rice mill, with initial glucose concentration 32. 4gl-1, by saccharomyces cerevisiae showed the maximum amount of ethanol production and yield,11.51gl-1 of 0.37 g ethanol/g total sugar. The highest cell dry weight and yield were 2.98 g biomass cell and 0.14 g CDW/g total sugar, respectively. Conclusion: Regarding the abundance of rice mill and the yield of ethanol production of this effluent yield, the rice mill can be used as a suitable substrate for the ethanol production.