Evaluation of hydrolytic enzymes in bioaugmented compost of Jatropha cake under aerobic and partial anaerobic conditions

Abstract

An experiment was conducted to analyze and evaluate the effect of microbial bio-augmentation on composting of Jatropha cake in terms of changes in physiochemical and hydrolytic enzymatic parameters. The microbial inoculums consisted of fungal strains, namely, Aspergillus awamori, Aspergillus nidulans, Trichoderma viride, and Phanerochaete chrysosporium,which were further amended with beneficial soil microorganisms like Pseudomonas striata and Azotobacter chroococcum after the thermophilic phase of Jatropha cake composting under aerobic and partial anaerobic conditions. Various physiochemical and enzymatic activities were estimated at various stages of composting. It was observed that the bio-augmented compost resulted in most desirable phosphorus availability (3.25 mg g-1) at the time of maturity. The hydrolytic activities cellulases (FPase, CMCase and cellobiase) and xylanase displayed a significant increase after 60 days indicating their contribution in the process of rapid decomposition. Our results indicate high germination index (80%) of the bio-augmented compost, which was significantly correlated to key enzymatic parameters and phosphorus content of compost. © Springer-Verlag and the University of Milan 2010.