Additional strains acting as key microbes promoted composting process.

Area of Science:

• Environmental Microbiology
• Waste Management
• Biotechnology

Background:

• Microbial inoculums (MIs) are utilized for biofortification in composting.
• Inefficient MIs and unclear mechanisms limit their effectiveness.
• This study addresses these limitations by investigating specific MIs.

Purpose of the Study:

• To evaluate the impact of different microbial inoculums on composting efficiency.
• To elucidate the mechanisms by which MIs enhance composting.
• To identify key microbial strains responsible for improved composting outcomes.

Main Methods:

• Composting experiments with three experimental groups (precise strains, commercial MI, Inoculum HJ) and one control group.
• Analysis of thermophilic period duration, physicochemical parameters (GI, pH, EC, moisture).
• High-throughput sequencing and microbial network analysis to assess microbial community structure and interactions.

Main Results:

• MIs significantly prolonged the thermophilic period (1.5-2.8 times).
• Inoculum HJ improved lignocellulose and organic matter degradation (1.22-1.25 times) and increased specific microbial genera abundance.
• MIs strengthened microbial interactions, with Inoculum HJ showing the most intensive interactions (1.20 times higher).
• Key OTUs in Inoculum HJ acted as hubs, increasing network complexity.

Conclusions:

• Specific microbial inoculums, particularly Inoculum HJ, enhance composting efficiency.
• The addition of MIs prolongs thermophilic phases and accelerates organic matter breakdown.
• Key microbial strains within effective MIs function as hubs, strengthening microbial networks and improving compost quality.