Effects of thermophiles inoculation on the efficiency and maturity of rice straw composting

The present study investigated the effects of separately or simultaneously inoculating thermophilic fungus Aspergillus fumigatus Z5 and bacterium Geobacillus stearothermophilus B5 on lignocellulose degradation, enzyme activities and humification during rice straw composting. The results indicated that inoculation of Z5 accelerated the rise of temperature in the mesophilic phase, and the degradation degree of cellulose and hemicellulose was increased by 25.3% and 20.7%, respectively, due to the higher activities of lignocellulolytic enzymes. Inoculation of B5 increased 5-7 °C of the compost temperature in the thermophilic phase, and also prolonged the duration from 33 to 41 days. Inoculated simultaneously, the secreted hydrolases of Z5 generated more nutrition and promoted the growth of B5. B5 maintained and increased the compost temperature, thus presenting a better hydrolysis environment for extracellular hydrolases. Thermophilic inoculation altered the main physicochemical factors and improved efficiency and maturity in rice straw composting.