Title of article :
Characterization of galactoglucomannan extracted from spruce (Picea abies) by heat-fractionation at different conditions
Author/Authors :
Lundqvist، نويسنده , , Jon and Jacobs، نويسنده , , Anna and Palm، نويسنده , , Magnus and Zacchi، نويسنده , , Guido and Dahlman، نويسنده , , Olof and Stهlbrand، نويسنده , , Henrik، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2003
Pages :
9
From page :
203
To page :
211
Abstract :
Water-soluble hemicelluloses were extracted from spruce chips by microwave heat-fractionation. The galactoglucomannan (GGM) extraction was evaluated on the basis of weight-average molecular weight (MW), yield and carbohydrate composition of the GGM. The MW was determined by size-exclusion chromatography with column calibration using off-line MALDI-MS analysis, and determination of mannan content in the fractions collected. Water impregnated spruce chips were heat-fractionated at three different temperatures (180, 190, and 200 °C). The spruce chips were also impregnated in NaOH solutions of different concentrations, and then heat-fractionated at 190 °C for 5 min. The highest mannan yield (78% based on the amount in the raw material) was obtained from water impregnated spruce chips heat-fractionated at 190 °C for 5 min (MW of 3800). The highest MW (14,000) was obtained from impregnation with 2% NaOH (190 °C, 5 min), but the yield of mannan was very low (3%). Impregnation with 0.025% NaOH and heat-fractionation at 190 °C for 5 min resulted in extraction of GGM with MW of 9500 and a mannan yield of 31%. When the spruce chips were impregnated with ≤0.05% NaOH an O-acetyl-galactoglucomannan was extracted, whereas when higher NaOH charges were used in the impregnation, the extracted GGM lacked acetyl groups.
Keywords :
Hemicellulose , O-acetyl-galactoglucomannan , Spruce (Picea abies) , Microwave oven , size-exclusion chromatography , MALDI-MS
Journal title :
CARBOHYDRATE POLYMERS
Serial Year :
2003
Journal title :
CARBOHYDRATE POLYMERS
Record number :
1612752
Link To Document :
بازگشت