The Effect of Thermophilic Deodorizing Bacteria on Nitrogen Loss and Promoting Kitchen Waste Composting

ABSTRACT Microbial inoculation represented a promising strategy for mitigating ammonia emissions during kitchen waste composting. Herein, two strains of thermophilic deodorizing bacteria ( Bacillus licheniformis and Bacillus subtilis ) were isolated and formulated as thermophilic microbial (TM) agent. During the 30‐day composting process, compared to control group (CK), the TM agent extended the high‐temperature period in the composting process by 2 days. TM agent significantly reduced the concentrations of NH 3 and H 2 S by 38.88% and 17.47%, whereas the nitrate nitrogen (NO 3 − ‐N) and total nitrogen (TN) content increased by 15.44% and 6.69%, respectively. Furthermore, the application of TM significantly increased humus content by three‐dimensional fluorescence spectroscopy and humus analysis. Additionally, the inoculation of TM agent enriched chitin‐decomposing ( Chitinophaga ) and ammonia‐assimilating ( Streptomyces ) bacteria. From the perspective of nitrogen cycling, the transformation of ammonium nitrogen (NH 4 + ‐N) was the key process for promoting nitrogen retention. The redundancy analysis (RDA) indicated that the transformation of NH 4 + ‐N was the key process for promoting nitrogen retention during the TM agent inoculation. Therefore, thermophilic deodorizing bacteria were identified as a potential inoculant to improve humus formation and enhance nitrogen conservation during kitchen waste composting.