title: Multifaceted characterization of cell wall decomposition products formed during ammonia fiber expansion (AFEX) and dilute acid based pretreatments.
abstract: Decomposition products formed/released during ammonia fiber expansion (AFEX) and dilute acid (DA) pretreatment of corn stover (CS) were quantified using robust mass spectrometry based analytical platforms. Ammonolytic cleavage of cell wall ester linkages during AFEX resulted in the formation of acetamide (25mg/g AFEX CS) and various phenolic amides (15mg/g AFEX CS) that are effective nutrients for downstream fermentation. After ammonolysis, Maillard reactions with carbonyl-containing intermediates represent the second largest sink for ammonia during AFEX. On the other hand, several carboxylic acids were formed (e.g. 35mg acetic acid/g DA CS) during DA pretreatment. Formation of furans was 36-fold lower for AFEX compared to DA treatment; while carboxylic acids (e.g. lactic and succinic acids) yield was 100-1000-fold lower during AFEX compared to previous reports using sodium hydroxide as pretreatment reagent.
authors.affiliation: Biomass Conversion Research Laboratory, Chemical Engineering and Materials Science, Michigan State University, 3900 Collins Road, Suite 1045, Lansing, MI 48910, USA. chundawa@msu.edu
authors.forename: Shishir P S
authors.initials: SP
authors.lastname: Chundawat
authors.forename: Ramin
authors.initials: R
authors.lastname: Vismeh
authors.forename: Lekh N
authors.initials: LN
authors.lastname: Sharma
authors.forename: James F
authors.initials: JF
authors.lastname: Humpula
authors.forename: Leonardo
authors.initials: L
authors.lastname: da Costa Sousa
authors.forename: C Kevin
authors.initials: CK
authors.lastname: Chambliss
authors.forename: A Daniel
authors.initials: AD
authors.lastname: Jones
authors.forename: Venkatesh
authors.initials: V
authors.lastname: Balan
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Dale
mesh_terms: D000468:Alkalies / Q000494:pharmacology; D000641:Ammonia / Q000378:metabolism*; D001709:Biotechnology / Q000379:methods*; D002244:Carbon / Q000032:analysis; D002264:Carboxylic Acids / Q000494:pharmacology; D002473:Cell Wall / Q000187:drug effects* / Q000378:metabolism*; D005663:Furans / Q000378:metabolism; D006868:Hydrolysis / Q000187:drug effects; D008031:Lignin / Q000378:metabolism; D009584:Nitrogen / Q000032:analysis; D009844:Oligosaccharides / Q000378:metabolism; D010100:Oxygen / Q000032:analysis; D012995:Solubility / Q000187:drug effects; D013464:Sulfuric Acids / Q000494:pharmacology*; D003313:Zea mays / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*
chemical_list: D000468:Alkalies; D002264:Carboxylic Acids; D005663:Furans; D009844:Oligosaccharides; D013464:Sulfuric Acids; D002244:Carbon; D000641:Ammonia; D008031:Lignin; D009584:Nitrogen; C033158:sulfuric acid; D010100:Oxygen