Statistical optimization of microalgal biodiesel production and protein extraction from Chlorella sorokiniana cultivated in dairy effluent

In this study, Chlorella sorokiniana isolated from natural pond water, was evaluated for simultaneous production of biodiesel and protein C. sorokiniana was cultivated under non-sterile conditions in dairy wastewater using large scale outdoor ponds and the biomass was processed for lipid production. Response surface methodology was applied to optimize the transesterification reaction variables and the optimum conditions were found to be reaction time (144 min), temperature (58 °C), oil to methanol ratio (1:6.8) and H 2 SO 4 as catalyst (3% w/v). A maximum yield of 95% (w/w) and 40% (w/w) of crude and decolorized algal biodiesel, was obtained under optimum conditions, respectively. Gas chromatography analysis of decolorized biodiesel confirmed the FAME yield of 88.3%. Amino acid profiling of algal protein revealed glycine (5%), glutamic acid (6%) and phenylalanine (3.3%) as some of the major amino acids.