Screening and Optimization of Fermentation Media for Increased Production of Ethanol from Gracilaria sp. using Response Surface Methodology

The study is aimed at identifying and optimizing physical parameters and
composition of fermentation media for enhanced ethanol production from Gracilaria
sp. (red macroalgae) by Saccharomyces cerevisiae using response surface methodology.
The sea weed was first undergone for acid hydrolysis and enzyme saccharification for
releasing of reducing sugar. These pretreated algal hydrolysates were used for optimization
study. The variables such as algal hydrolysate, incubation period, Na2HPO4 and pH were
found to be significant variables to influence the ethanol production. The identified
variables were optimized by Box Benhen design (BBD). The optimum conditions are: algal
hydrolysates - 8.5%, incubation period - 1.7 days, Na2HPO4 - 0.3gL-1 and pH - 6.1. These
conditions were validated by scale up study which revealed an increased production of
ethanol (23.612 gL-1).