Table 3.

Inhibition effects of different WSL on enzymatic hydrolysis

Lignin type	Enzyme	Substrate	Enzymatic hydrolysis	Hydrolysis yield	Refs.
Commercial sodium LS from poplar	Cellic CTec 2	Whatman filter paper	2% (w/v), pH = 4.8, 50 °C, 200 rpm and 72 h	Improved by 30.0% to 46.0% with low Mw fraction	[129]
LS from hydrolysate of sulfite pretreated lodgepople pine	Celluclast and Novozyme 188	Lodgepople pine	2% (w/v), pH = 5.5, 50 °C, 200 rpm and 72 h	Improved from 51.0 to 90.0%	[119]
Reax 85A	Cellic CTec 2	Acid bisulfite pretreated poplar	2% (w/v), pH = 5.4, 50 °C, 180 rpm and 48 h	Improved from 76.4 to 83.5%	[120]
Commercial sodium LS	Cellic CTec 2	Kraft pulping produced lodgepole pine	2% (w/v), pH = 4.8, 50 °C, 200 rpm and 72 h	Improved from 33.0 to 55.0%	[121]
LS from sulfite pretreated poplar	Cellulase mixture	Sulfite pretreated poplar	2% (w/v), pH = 4.8 or 5.2, 50 °C, 200 rpm and 96 h	Improved by 5% to 9%, respectively, at pH 4.8 and pH 5.2	[130]
LS from poplar sulfite pulping	Cellic CTec 2	A mixture of the cellulose	2% (w/v), pH = 4.8, 50 °C, 200 rpm and 72 h	Improved from 52.0 to 67.0%	[123]
Water-soluble alkaline lignin	Cellic CTec 2	Sodium hydroxide pretreated wheat straw	2% (w/v), pH = 4.8, 50 °C, 180 rpm and 72 h	Improved from 66.8 to 76.9%	[122]
Reax 85A (sulfomethylated softwood kraft lignin)	Cellic CTec 2	GLMP	5% (w/v), pH = 4.8, 50 °C, 180 rpm and 96 h	Improved from 42.0 to 75.0%	[16]