Characterization of Thermophilic Lignocellulolytic Microorganisms in Composting

Author: mycolabadmin
2021-08-11
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Summary

This research examined how heat-loving microorganisms break down plant waste during composting. The study found that different types of microorganisms work together to decompose tough plant materials – bacteria break down certain components throughout the process while fungi handle the more difficult parts later on. This has important real-world applications: • More efficient composting systems for handling organic waste • Development of heat-stable enzymes for industrial applications • Better understanding of how to recycle plant materials into useful products • Potential for creating new environmentally-friendly industrial processes • Improved methods for breaking down agricultural waste materials

Background

Composting involves the selection of microbiota capable of resisting high temperatures and degrading lignocellulose. Understanding the thermophilic microbial community involved in this biotransformation is valuable for improving composting efficiency and providing thermostable biomass-degrading enzymes for biorefinery applications.

Objective

This study investigated the lignocellulose-degrading thermophilic microbial culturome at all stages of plant waste composting, focusing on the dynamics, enzymes, and thermotolerance of each member of such a community. The research aimed to quantify thermophilic microorganisms and their lignocellulolytic representatives during composting, analyze their ability to degrade cellulose, hemicellulose and lignin, determine their thermal tolerance ranges, and select specific strains with potential applications for thermostable enzyme production.

Results

The study found that 58% of holocellulose and 7% of lignin were degraded by the end of composting. The entire fungal thermophilic population showed lignocellulose-degrading activity, while only 8-10% of thermophilic bacteria had this trait, specifically for hemicellulose degradation. The bacterial isolates (159 strains) were mostly Firmicutes (96%) with some Actinobacteria (2%) and Proteobacteria (2%). The most prevalent species were Bacillus licheniformis and Aeribacillus pallidus. Thermophilic fungi (27 strains) comprised only four species: Thermomyces lanuginosus, Talaromyces thermophilus, Aspergillus fumigatus, and Gibellulopsis nigrescens.

Conclusion

The study demonstrated that bacteria and fungi play complementary roles in lignocellulose degradation during composting, with bacteria primarily breaking down hemicellulose throughout the process while fungi handle cellulose and lignin degradation in later stages. Several strains showed potential for thermostable enzyme production, particularly B. thermoamylovorans, G. thermodenitrificans, T. lanuginosus, and A. fumigatus. The research provides insights into microbial adaptation mechanisms during composting and identifies promising candidates for biotechnological applications.

Published in:Frontiers in Microbiology,
Study Type:Experimental Research,
Source: 10.3389/fmicb.2021.697480