Enhancement of Lignin Biopolymer Isolation from Hybrid Poplar by Organosolv Pretreatments

Table 1

Yields (% Klason lignin) and neutral sugar compositions (% dry weight, w/w) of the alcohol lignin fractions extracted from hybrid poplar.

	Lignin preparations^a
	MOL	EOL	POL	BOL
Yield^b (%)	45.5	72.1	51.4	5.7
Total sugars (%)	1.16	1.41	1.46	7.53
Arabinose	0.07	0.06	ND^c	0.70
Galactose	0.10	0.10	0.05	0.43
Glucose	0.22	0.20	0.11	2.45
Xylose	0.77	1.05	1.30	3.28
Mannose	ND	ND	ND	0.45
Rhamnose	ND	ND	ND	0.09
Glucuronic acid	ND	ND	ND	0.13

MOL, EOL, POL, and BOL represent lignin fractions extracted with aqueous methanol, ethanol, 1-propanol, and 1-butanol, respectively.
^bYield means the percentage of the extracted lignin to the initial wood Klason lignin content.
^cND: not detected.