AUTHOR=Ma Yulin , Chen Xu , Zahoor Khan Muhammad , Xiao Jianxin , Liu Shuai , Wang Jingjun , Alugongo Gibson Maswayi , Cao Zhijun 

TITLE=Biodegradation and hydrolysis of rice straw with corn steep liquor and urea-alkali pretreatment

JOURNAL=Frontiers in Nutrition

VOLUME=9

YEAR=2022

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2022.989239

DOI=10.3389/fnut.2022.989239

ISSN=2296-861X

ABSTRACT=<p>The current study evaluated the corn steep liquor (CSL) and urea-alkali pretreatment effect to enhance biodegradation and hydrolysis of rice straw (RS) by ruminal microbiome. The first used RS (1) without (Con) or with additives of (2) 4% CaO (Ca), (3) 2.5% urea plus 4% CaO (UCa) and (4) 9% corn steep liquor + 2.5% urea + 4% CaO (CUCa), and then the efficacy of CSL plus urea-alkali pretreatment was evaluated both <italic>in vitro</italic> and <italic>in vivo</italic>. The Scanning electron microscopy, X-ray diffraction analysis, cellulose degree of polymerization and Fourier-transform infrared spectroscopy, respectively, results showed that Ca, UCa, and CUCa pretreatment altered the physical and chemical structure of RS. CSL plus Urea-alkali pretreated enhanced microbial colonization by improving the enzymolysis efficiency of RS, and specially induced adhesion of <italic>Carnobacterium</italic> and <italic>Staphylococcus</italic>. The CUCa pretreatment could be developed to improve RS nutritional value as forage for ruminants, or as feedstock for biofuel production.</p>