Elephant grass (Pennisetum purpureum Schum.) pretreated via steam explosion as a carbon source for cellulases and xylanases in submerged cultivation

• Steam explosion pretreatment elephant grass is a efficient substrate for enzyme production.
• The most promising pretreatment was at 190 °C for 8 and 6 min.
• Steam explosion pretreatments showed a negative result for xylanase.

The cost of hydrolytic enzymes is one bottleneck for economic production of second generation ethanol and the use of low cost substrates is required. The use of elephant grass for the production of hydrolytic enzymes is a promising alternative due its high productivity, but it requires pretreatment. In this context, the steam explosion method appears to be advantageous for producing structural changes in the lignocellulosic material, making the biomass more accessible to enzymatic action. The elephant grass was pretreated via steam explosion – at 180, 190 and 200 °C, with residence times of 6, 8 and 10 min – for the production of cellulases and xylanases by Penicillium echinulatum S1M29 in submerged cultivation was evaluated. The biomass that was pretreated at 190 °C for 8 and 6 min showed a positive result for filter paper activity (FPA), endoglucanases and β-glucosidases, since the biomass is washed with water after the pretreatment. All of the pretreatments showed a negative result for xylanase. The results indicate that elephant grass that has been pretreated using steam explosion can be used as a substrate for the production of enzymes for the hydrolysis of lignocellulosic biomass.