Journal of Research

Chopped paddy straw (30-40 mm size) was pretreated with Penicillium sp. to enhance its digestibility and biogas production. The potential of microbial pretreatment of paddy straw was investigated at regular interval of 5, 10, 15 and 20 days by determining the change in proximate composition of paddy straw like cellulose, hemicellulose, lignin and silica content. The pretreated straw was used for biogas production in 2 L capacity biogas digesters. Results indicate that the cellulose, lignin and silica contents decreased by 13.6 per cent, 8.5 per cent & 26.7 per cent, respectively. However, hemicellulose content increased by 19.4 per cent. Biogas production also increased by 18.6 per cent in 5 days pretreated sample. The significantly higher reduction of silica as compared to lignin content in the pretreated straw indicates that removal of silica by Penicillium sp. might be more responsible for increasing paddy straw digestibility and biogas production