Optimization of fermentation factors to enhance rice straw degradation ability using a microbial consortium LZF-12

Abstract

Biological pretreatment has broad application prospects in agricultural waste treatment because of its economic benefits, environmental protection and energy saving characteristics. In this study, a microbial consortium LZF-12 was applied for a biological pretreatment to degrade rice straw. Batch experiments were performed under hydrolysis conditions by using the method of Box-Behnken factorial design (BBD). The results showed that the model multiple correlation coefficient R 2 was 0.9816, and the effects of three factors on the degradation of rice straw of LZF-12 as descending order were the initial rice content, chicken manure content, and initial pH value. The interaction between straw concentration, chicken manure concentration, and initial pH value had significant effects on the degradation of a microbial consortium. Under the optimum conditions of 0.86% rice straw, 0.5% chicken manure and the initial pH value of 7.0, the degradation rate of rice straw reached 72.4%. There is only a small difference of 0.55% between the experimental value and predicted value from BBD model. Therefore, it is feasible for the established model due to the consistent results between the prediction and experimental value. The microbial consortium LZF-12 has high cellulase enzyme activities and degradation ability over a wide range of temperature and pH value, indicating that it has a good development potential and application prospects in waste biodegradation and biomass energy production.

Effects of background fertilization followed by co-application of two kinds of bacteria on soil nutrient content and rice yield in Northeast China

“…Microbial fertilizer refers to a specific type of product containing live microorganisms, which can be used in agricultural production to obtain specific fertilizer effects [13] . In this effect, live microorganisms play a key role [14][15][16] . In 1885, Berthelot's basin experiments showed that microorganisms could convert nitrogen from the air into soil nitrogen that could be absorbed by plants through nitrogen fixation [17] .…”