Identification and characterization of potential compost degrading bacteria from agro-waste

Abstract

Agricultural industry plays a significant role in the global economic growth. It is estimated more than 15% of total waste in Asia are contributed by agro waste. Bacteria is known as one of the useful organisms actively found to surround the waste industry. They are considered as chemical decomposers and act as driving agent of composting that changes the chemistry of organic waste to simple compounds. Thus, this study was conducted to isolate and identify potential compostdegrading bacteria from agriculture waste at several sampling areas in Besut district, Terengganu, Malaysia. A total of 49 bacteria strains were isolated using Tryptic Soya Agar (TSA) from seven groups of raw agro wastes (paddy husk, paddy straw, paddy soil, rock melon waste, rock melon soil, corn waste, and corn soil). Primary screening for potential enzyme production was carried out using selective media containing different substrates (sucrose, xylan, starch, skim milk, and pectin). Only 13 bacterial strains were found positive for protease, nine bacteria strains positive for xylanase, and three bacteria strains were found positive for amylase. Identification of bacteria strains were performed using phenotypic, biochemical tests, and genotypic approaches by 16S rRNA gene sequence. Based on NCBI BLAST analysis, we have identified several bacteria strains: Bacillus cereus (strain B), Alcaligenes faecalis (strain C), Micrococcus sp. (strain D), Pseudomonas stutzeri (strain E), Enterobacter cloacae (strain G), and Serratia marcescens (strain J). Strain F and strain H were identified under distinct family of Enterobacteriaceae, while strain I was identified from Pseudomonadeles order which might represent a new type of proteobacteria strain. These potential waste degrading bacteria could be further analyzed and studies for their true potential in many areas including agriculture and industrial waste management as an approach to reduce waste accumulation in eco-friendly way.