Bioethanol production from starch by glucose cerevisiae assessed with Response Surface Methodology (RSM)

Saccaromyces cerevisiae has many different uses such as baker's yeast and bioethanol production. Response surface methodology (RSM) is a complex of statistical techniques for experimental model creation. In this study was done to determination of optimal condition of bioethanol production from starch by yeast using RSM. Initially saccaromyces cerevisiae was proliferated on agar then by α-amylase, dextranase and amyloglucosidase respectively, then starch 5% was hydrolyzed to glucose. 250 cc glucose was put at 30 C° and velocity of 150 rpm for 36 h. Bioethanol quantity was evaluated by dichromate oxidation and ethanol measurement methods and temperature, time and pH variables were considered at 25-98 C°, 1 to 6 weeks and 3 to7, respectively. The highest bioethanol production was 12.5 ml at 30 C°, pH 4 also at 80 C°, pH 7 for 5 weeks. The lowest bioethanol production was 3 ml at 98 C°, pH 7 for 1 week which was practically compatible. Regarding the results, RSM method has many benefits such as increase in efficiency of chemical reactions, prevention of wasting raw material, time, money and energy which could use in different biological reactions.