Biobutanol Production from Agricultural Raw Materials by Clostridium spp.

Abstract

Spore activation of Clostridium spp. is one of the most important steps in butanol production. Among three different methods (microwave shock, ultrasonic shock and heat shock), heat shock at 80 °C for 1 min was found to be the best method for activation of Clostridium spores for use as an inoculum for butanol production. Evaluation of the performance of four Clostridium spp., i.e., C. beijerinckii JCM 1390, C. acetobutyricum JCM 7829, C. beijerinckii TISTR 1461 and C. beijerinckii TISTR 1462 for butanol production from synthetic medium (P2 medium) containing 60 g l-1 of glucose at 37 °C revealed that C. beijerinckii TISTR 1461 gave the highest butanol concentration (PB, 10.41 g l-1). Three agricultural raw materials, i.e., sweet sorghum juice, sugarcane juice and sugarcane molasses, containing 60 g l-1 of total sugar, were used as butanol production media by C. beijerinckii TISTR 1461. Its PB values were 1.40, 4.37 and 7.45 g l-1, respectively. Additionally, when sugarcane molasses was supplemented with the components of P2 medium (excluding glucose), its PB value increased to 11.48 g l-1. The results demonstrated that sugarcane molasses has high potential for use as a raw material for butanol production.