BioChem - DOS

Probing the nature of AFEX-pretreated corn stover derived decomposition products that inhibit cellulase activity

Bioresource technology : biomass, bioenergy, biowastes, conversion technologies, biotransformations, production technologies

Humpula, J.F.; Uppugundla, N.; Vismeh, R.; Sousa, L.; Chundawat, S.P.S.; Jones, A.D.; Balan, V.; Dale, B.E.; Cheh, A.M.

Sequential fractionation of AFEX-pretreated corn stover extracts was carried out using ultra-centrifugation, ultra-filtration, and solid phase extraction to isolate various classes of pretreatment products to evaluate their inhibitory effect on cellulases. Ultra-centrifugation removed dark brown precipitates that caused no appreciable enzyme inhibition. Ultra-filtration of ultra-centrifuged AFEX-pretreated corn stover extractives using a 10kDa molecular weight cutoff (MWCO) membrane removed additional high molecular weight components that accounted for 24-28% of the total observed enzyme inhibition while a 3kDa MWCO membrane removed 60-65%, suggesting significant inhibition is caused by oligomeric materials. Solid phase extraction (SPE) of AFEX-pretreated corn stover extractives after ultra-centrifugation removed 34-43% of the inhibition; ultra-filtration with a 5kDa membrane removed 44-56% of the inhibition and when this ultra-filtrate was subjected to SPE a total of 69-70% of the inhibition were removed. Mass spectrometry found several phenolic compounds among the hydrophobic inhibition removed by SPE adsorption.

2014

Elsevier Applied Science

0960-8524

152

pp.38-45

10.1016/j.biortech.2013.10.082

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART68367046

AFEX; Ultra-filtration; Fractionation; Cellulase; Inhibition