Application of response surface methodology for statistical optimization of lipase production by penicillium sp. Employing solid state fermentation

Abstract

This study was conducted to determine the economical and optimal in vitro growth requirements of Penicillium sp. for augmented production of lipases. The optimization of eco-cultural parameters was carried out for solid state fermentation. Preliminary batch testing was performed to find out the favourable conditions for enhanced lipase productivity. The results showed maximal lipase productivity when 10g of the sunflower hulls was utilized as a basal substrate for 3 ml inoculum of Penicillium sp. For obtaining the highest enzyme yields the moisture content of the medium was adjusted at 40% with phosphate buffer (pH 6.0), which was in favour of the fermentation performed at 30ºC for 72 h. The best quantified production of extracellular lipases was recorded with Tween-80 as the extraction medium. As per Response surface methodology (RSM) model, Box-Behnken experimental design was employed in order to analyse the interactive effects of critical medium components on lipase yield obtained from Penicillium sp. The optimum concentration of olive oil as additional oil (5%), Tween-80 (3%) and peptone (1%) resulted in maximal enzyme productivity (100.45 U/mg), approximately three times greater than that observed in basal medium. The analysis of variance showed that the devised model was significant (p < 0.05).