Optimization of enzymatic cell disruption for improving lipid extraction from schizochytrium sp. Through response surface methodology

Abstract

This study is aimed to explore the optimal conditions of cell disruption in the extraction algae oil process, using alkaline protease to disrupt cell of Schizochytrium sp. to extract oil in this paper. The effects of enzymatic lysis temperature, enzymatic lysis time, enzyme dosage and pH value on oil yield and DHA yield were studied. Through the combination of single factor test and response surface design, the optimal cell disruption conditions were screened out. The fatty acid composition of algal oil was analyzed by gas chromatography-massspectrometry (GC-MS). The results showed that when the conditions were: enzymatic lysis temperature 55℃, enzymatic lysis time 9 h, enzyme dosage 3% of biomass and pH 8,oil yield and DHA yield reached the highest 14.52 g/L and 7.12 g/L, respectively. When the strains were cultured in 50 L fermentor, oil yield reached 26.27 g/L and DHA yield reached 12.89 g/L. They were 1.81 times higher than that in shake-flask cultivation. The optimization experiment provides the basis for the industrial production of Schizochytrium sp.