Straw lignin degradation by lignin peroxidase from Irpex lacteus cooperated with enzymes and small molecules.

Abstract

Maximizing the utility value of enzymes was achieved by exploring the effects of small molecules on the efficiency of lignin degradation by lignin peroxidase. Using wheat straw as raw material and taking lignin degradation rate as index, it was found that laccase, glucose oxidase, malonic acid, citric acid, ZnSO4, CaCl2 could promote the lignin degradation by the lignin peroxidase from Irpex lacteus, respectively. Moreover, glucose oxidase, malonic acid and CaCl2 had obvious synergy effects on lignin degradation by the lignin peroxidase. The optimal conditions of lignin degradation were obtained by response surface experiment: 4% glucose oxidase, 0.74% malonic acid and 3.29% CaCl2 were added for synergistic degradation at 37℃ with 50% of water content. After 72h quickly enzymatic hydrolysis, the degradation rate of lignin was 45.84%. A new green and efficient method for lignin removal from straw was obtained, which provided a reference for the efficient utilization of straw and lignin peroxidase.