Produção de etanol a partir de torta de mamona (Ricinus communis L.) e avaliação da letalidade da torta hidrolisada para camundongos

Abstract

Recebido em 17/5/07; aceito em 31/10/07; publicado na web em 15/5/08 ETHANOL PRODUCTION FROM CASTOR BEAN CAKE (Ricinus communis L.) AND EVALUATION OF THE LETHALITY OF THE CAKE FOR MICE. The castor bean cake is rich in starch (48 ± 0.53%) and bears a problem linked to the occurrence of a toxic protein (ricin). The chemical hydrolysis (ratio solid:liquid = 1:6; H 2 SO 4 = 0.1 mol L-1 ; 120 °C; 40 min) generated a medium with 27 g L-1 of reducing sugars (hydrolysis efficiency= 32%). The hydrolyzed product was fermented and produced 11 g L-1 of ethanol (volumetric productivity=1.38 g L-1 h-1 and ethanol yield on substrate consumed=0.45 g g-1). In vivo experiments (DL50) revealed a reduction of roughly 240 times in the CBC toxicity (2.11 μg g-1).