Huang et al., "Identification of three important amino acid residues of xylanase AfxynA from Aspergillus fumigatus for enzyme activity and formation of xylobiose
as the major product," Process Biochemistry, vol.
The presence of readily metabolizable carbon sources like glucose, cellobiose, xylobiose, or xylose represses the synthesis of xylanase enzymes for the utilization of certain carbon sources such as xylan or cellulose and the process is known as catabolite repression.
The synthesis of xylanases and cellulases is repressed if easily metabolizable carbon source like glucose, cellobiose, xylose, or xylobiose is present .
Molecular weight standard mix containing xylose, xylobiose
, xylotriose, xylotetraose, xylopentaose, and xylohexaose (Megazyme) was the gift from Professor Khanok Ratanakhanokchai, KMUTT, Thailand.
Endo-[beta]-1,4-xylanase (EXN) depolymerizes xylan to shorter xylobiose
and xylooligomers  while [beta]-1,4-xylosidases (XYL) hydrolyzes xylobiose
and xylooligomers to D-xylose generated by the action of endo-xylanases (EXN).
The concentration of xylooligosaccharides (Xylobiose
) (Megazyme, Ireland) in the enzymatic hydrolysate was determined by high performance liquid chromatography (HPLC, Waters pump 515 model) equipped with Waters 2414 refractive index (RI) detector.
Invertase, the enzyme that catalyzes the hydrolysis of sucrose to D-glucose and D-fructose, sugars that are important sources of energy for microorganisms (Jin et al., 2009); xylanase, the enzyme that hydrolyzes xylan to release xylobiose
and xylose; and urease activity all diminished in soils fertilized with N[P.sub.2][O.sub.5]K and copper sulfate ([Cu.sub.2]S[O.sub.4]) (Butt et al., 2008).
The reducing disaccharides are maltose, isomaltose, cellobiose, gentiobiose, xylobiose
, mannobiose, and lactose.
Method for obtaining saccharide liquid consisting essentially of xylobiose
from hemicellulose liquor.
Takamizawa, "Purification and characterization of Aeromonas caviae ME-1 xylanase V, which produces exclusively xylobiose
from xylan," Applied and Environmental Microbiology, vol.