1. |
|
|
2. |
|
|
3. |
|
|
4. |
|
|
5. |
- Shaw, Philip, et al.
(författare)
-
Genre across cultures
- 2004
-
Ingår i: World Englishes. - 0883-2919 .- 1467-971X. ; 23:3, s. 385-401
-
Tidskriftsartikel (refereegranskat)
|
|
6. |
- Stålbrand, Henrik, et al.
(författare)
-
Isolation, characterization, and enzymatic hydrolysis of acetyl-galactoglucomannan from spruce (Picea abies)
- 2004
-
Ingår i: Hemicelluloses. Science and Technology (ACS Symposium Series). - 0097-6156. - 9780841238428 - 0841238421 ; 864, s. 66-78
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Water-soluble hemicelluloses were extracted from spruce chips by heat-fractionation using microwave treatment. A screening of conditions (pH, temperature and residence time) was performed for the extraction of O-acetyl-galactoglucomannan (AcGGM). The yield and the average molecular weight of the extracted mannan were analysed using HPLC, size-exclusion chromatography (SEC) and mass-spectrometry. The pH during heat fractionation influenced the yield and the structure of AcGGM. The highest yield (78%) of AcGGM (average molecular weight 3800) was achieved with heat-fractionation in water at 190degrees C for 5 minutes. With 0.025% NaOH, an average molecular weight of 9500 was obtained at a yield of 30%. AcGGM molecular weight standard molecules were prepared using SEC. The structure of the AcGGM was determined using H-1-NMR. The enzymatic hydrolysis of AcGGM was studied using beta-mannanase and alpha-galactosidase.
|
|