Research progress in straw-degrading psychrotrophic microorganisms

Abstract:

A large quantity of straw waste is produced in northern China, the main area of agricultural production. The complex three-dimensional structure formed by lignin, cellulose, and hemicellulose makes straw difficult to be degraded. Furthermore, the low temperature environment after harvest enhances the difficulty of straw degradation. Psychrotrophic microorganisms could promote straw degradation at low temperatures. Straw-degrading microorganisms include bacteria and fungi. Among them, fungi are powerful in lignin degradation. Bacteria have low lignin-degrading activities but high tolerance to low temperatures. Because the degradation of straw is coordinated by many enzymes, straw is difficult to be completely degraded by single strains. Psychrotrophic strain combinations with powerful straw decomposition performance are widely used in straw degradation. These combinations can be obtained by screening of strains from the nature, mixing of strains, and acclimation to temperature gradients. This review provides technical reference for efficiently screening straw-degrading microorganisms and promoting straw utilization under low temperature conditions.