Ting Li, Kehui OuYang, Qinghua Qiu, Xianghui Zhao, Chanjuan Liu
{"title":"A lysing polysaccharide monooxygenase from Aspergillus niger effectively facilitated rumen microbial fermentation of rice straw.","authors":"Ting Li, Kehui OuYang, Qinghua Qiu, Xianghui Zhao, Chanjuan Liu","doi":"10.5713/ab.24.0026","DOIUrl":null,"url":null,"abstract":"<p><strong>Objective: </strong>This study investigated the impact of Aspergillus niger lysing polysaccharide monooxygenase (AnLPMO) on in vitro rumen microbial fermentation of rice straw.</p><p><strong>Methods: </strong>AnLPMO was heterologously expressed in Escherichia coli. Fourier transform infrared spectrometry and X-ray photoelectron spectroscopy analyzed the surface structure of rice straw after AnLPMO treatment. Two in vitro experiments, coupled with 16S highthroughput sequencing and quantitative real-time polymerase chain reaction techniques, assessed the influence of AnLPMO on rumen microbial fermentation of rice straw.</p><p><strong>Results: </strong>AnLPMO exhibited peak activity at 40°C and pH 6.5, with a preference for rice straw xylan hydrolysis, followed by Avicel. AnLPMO application led to the fractional removal of cellulose and hemicelluloses and a notable reduction in the levels of carbon elements and C-C groups present on the surface of rice straw. Compared to the control (no AnLPMO), supplementing AnLPMO at 1.1 to 2.0 U significantly enhanced in vitro digestibility of dry matter (IVDMD, p<0.01), total gas production (p<0.01), and concentrations of total volatile fatty acids (VFA, p<0.01), acetate (p<0.01), and ammonia-N (p<0.01). Particularly, the 1.4 U AnLPMO group showed a 14.8% increase in IVDMD. In the second experiment, compared to deactivated AnLPMO (1.4 U), supplementing bioactive AnLPMO at 1.4 U increased IVDMD (p = 0.01), total gas production (p = 0.04), and concentrations of total VFA (p<0.01), propionate (p<0.01), and ammonia-N (p<0.01), with a limited 9.6% increase in IVDMD. Supplementing AnLPMO stimulated the growth of ruminal bacterial taxa facilitating fiber degradation, including Proteobacteria, Spirochaetes, Succinivibrio, Rikenellaceae_RC9_ Gut_Group, Prevotelaceae_UCG-003, Desulfovibrio, Fibrobacter succinogenes, Ruminococcus albus, R. flavefaciens, Prevotella bryantii, P. ruminicola, and Treponema bryantii.</p><p><strong>Conclusion: </strong>These findings highlight AnLPMO's potential as a feed additive for improving rice straw utilization in ruminant production.</p>","PeriodicalId":7825,"journal":{"name":"Animal Bioscience","volume":" ","pages":"1738-1750"},"PeriodicalIF":2.4000,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11366511/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Animal Bioscience","FirstCategoryId":"97","ListUrlMain":"https://doi.org/10.5713/ab.24.0026","RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/5/7 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"AGRICULTURE, DAIRY & ANIMAL SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
Objective: This study investigated the impact of Aspergillus niger lysing polysaccharide monooxygenase (AnLPMO) on in vitro rumen microbial fermentation of rice straw.
Methods: AnLPMO was heterologously expressed in Escherichia coli. Fourier transform infrared spectrometry and X-ray photoelectron spectroscopy analyzed the surface structure of rice straw after AnLPMO treatment. Two in vitro experiments, coupled with 16S highthroughput sequencing and quantitative real-time polymerase chain reaction techniques, assessed the influence of AnLPMO on rumen microbial fermentation of rice straw.
Results: AnLPMO exhibited peak activity at 40°C and pH 6.5, with a preference for rice straw xylan hydrolysis, followed by Avicel. AnLPMO application led to the fractional removal of cellulose and hemicelluloses and a notable reduction in the levels of carbon elements and C-C groups present on the surface of rice straw. Compared to the control (no AnLPMO), supplementing AnLPMO at 1.1 to 2.0 U significantly enhanced in vitro digestibility of dry matter (IVDMD, p<0.01), total gas production (p<0.01), and concentrations of total volatile fatty acids (VFA, p<0.01), acetate (p<0.01), and ammonia-N (p<0.01). Particularly, the 1.4 U AnLPMO group showed a 14.8% increase in IVDMD. In the second experiment, compared to deactivated AnLPMO (1.4 U), supplementing bioactive AnLPMO at 1.4 U increased IVDMD (p = 0.01), total gas production (p = 0.04), and concentrations of total VFA (p<0.01), propionate (p<0.01), and ammonia-N (p<0.01), with a limited 9.6% increase in IVDMD. Supplementing AnLPMO stimulated the growth of ruminal bacterial taxa facilitating fiber degradation, including Proteobacteria, Spirochaetes, Succinivibrio, Rikenellaceae_RC9_ Gut_Group, Prevotelaceae_UCG-003, Desulfovibrio, Fibrobacter succinogenes, Ruminococcus albus, R. flavefaciens, Prevotella bryantii, P. ruminicola, and Treponema bryantii.
Conclusion: These findings highlight AnLPMO's potential as a feed additive for improving rice straw utilization in ruminant production.