Exploration of Multi-Source Lignocellulose-Degrading Microbial Resources and Bioaugmentation Strategies: Implications for Rumen Efficiency

Abstract

Utilizing straw feed is an effective strategy to optimize straw resource utilization by incorporating microbial degradation agents to expedite lignocellulose breakdown and enhance feed efficiency. Lignocellulose-degrading species and microbial communities are present in various Earth ecosystems, including the rumen of ruminants, insect digestive tracts, forest soil, and microbial populations in papermaking processes. The rumen of ruminants harbors a diverse range of microbial species, making it a promising source of lignocellulose-degrading microorganisms. Exploring alternative systems like insect intestines and forest soil is essential for future research. Current studies primarily rely on traditional microbial isolation techniques to identify lignocellulose-degrading strains, underscoring the necessity to transition to utilizing microbial culturomics and genome-editing technologies for discovering and manipulating cellulose-degrading microbes. This review provides an overview of lignocellulose-degrading microbial communities from diverse environments, encompassing bacterial and fungal populations. It also delves into the use of metagenomic, metatranscriptomic, and metaproteomic approaches to pinpoint highly efficient cellulase genes, along with the application of genome-editing tools for engineering lignocellulose-degrading microorganisms. The primary objective of this review is to offer insights for further exploration of potential lignocellulose-degrading microbial resources and high-performance cellulase genes to enhance roughage utilization in ruminant rumen ecosystems.