Metagenomic Analysis of Microbial Community Associated with Food Waste Composting.

Abstract

Food waste is an increasing cause of concern in India. Its management through composting plays a vital role in managing the biodegradable fraction of municipal solid waste. However, the existing composting process has many challenges, such as the lack of optimum microenvironment and microbiome knowledge, which limits efficient outcomes. Therefore, the present study aims to bridge the gap by applying metagenomics to study microbial community dynamicity during different stages of composting. The bacterial community analysis showed that genus Marionobacter (9.4%) and Halomonas (7.4%) were prevalent during the mesophilic stage, whereas the Bacillus (12.2%) and Cellulomonas (0.1%) were prevalent during the thermophilic and maturation stage of composting. The functional profiling of metagenome indicated the abundance of genes involved in degradation of polymeric compounds such as carbohydrates, lipids, and proteins. The relative abundance of arginine and proline metabolisms increased during the thermophilic stage. Whereas the relative abundance of genes involved in fatty acid, tryptophan, galactose, and propanoate metabolisms declined. Similarly, the CAZyme tool predicted that the genes encoding for glycoside hydrolase (GH) families were higher during the mesophilic and thermophilic stages of composting. These enzymes play an important role in degradation of complex polysaccharides such as cellulose and hemicellulose. The data obtained from the present study could be utilized for the optimization and improving the composting process.