Recently, great emphasis has been placed on 2nd-generation biofuels produced from lignocellulosic feedstocks to elude the ethical problems that may arise from the use of food crops. The biochemical route has focused much research, presenting potentially a greater cost reduction than the thermochemical route. During steam-explosion (SE) pretreatment, mandatory for cellulose accessibility, lignocellulosic biomasses release, among the others, phenolic compounds that inhibit or inactivate to some extent the biocatalysts involved in the hydrolysis or fermentation step. This study focusses on the effect that selected phenolics causes on the stability and activity of cellulase. To this end continuous stirred UF-membrane reactors have been used to follow enzyme activity in long term-runs that lasted at least 100 h. The inhibiting and/or inactivating effects of components released during SE were studied at different concentrations in the enzymatic hydrolysis of commercial cellulose. p-Hydroxybenzoic acid and syringaldehyde (2 g L-1) appears to be the extreme limits in the inactivating effect being the half-lives 12.6 and 82.5 h, respectively.
The Impact of Lignocellulose Degradation Compounds on the Activity and Stability of Cellulase during CMC-Hydrolysis Performed in Continuous UF-Membrane Reactors
CANTARELLA, Laura;
2013-01-01
Abstract
Recently, great emphasis has been placed on 2nd-generation biofuels produced from lignocellulosic feedstocks to elude the ethical problems that may arise from the use of food crops. The biochemical route has focused much research, presenting potentially a greater cost reduction than the thermochemical route. During steam-explosion (SE) pretreatment, mandatory for cellulose accessibility, lignocellulosic biomasses release, among the others, phenolic compounds that inhibit or inactivate to some extent the biocatalysts involved in the hydrolysis or fermentation step. This study focusses on the effect that selected phenolics causes on the stability and activity of cellulase. To this end continuous stirred UF-membrane reactors have been used to follow enzyme activity in long term-runs that lasted at least 100 h. The inhibiting and/or inactivating effects of components released during SE were studied at different concentrations in the enzymatic hydrolysis of commercial cellulose. p-Hydroxybenzoic acid and syringaldehyde (2 g L-1) appears to be the extreme limits in the inactivating effect being the half-lives 12.6 and 82.5 h, respectively.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
