K-XYLX6-2V | endo-Xylanase Assay Kit (XylX6 method 200A)

Product code: K-XYLX6-2V

The XylX6 assay reagent for the measurement of endo-xylanase (endo-1,4-β-xylanase) contains two components; 1) 4,6-O-(3-Ketobutylidene)-4-nitrophenyl-β-D-45-glucosyl-xylopentaoside and 2) β-xylosidase. The ketone blocking group prevents any hydrolytic action by the β-xylosidase or other exo-acting glycosidases on the XylX6 substrate. Incubation with an endo-xylanase generates a non-blocked colourimetric oligosaccharide that is rapidly hydrolysed by the ancillary β-xylosidase. The rate of formation of 4-nitrophenol is therefore directly related to the hydrolysis of XylX6 by the endo-xylanase. The reaction is terminated and the phenolate colour is developed on addition of Tris buffer solution (pH = 10.0).


Colourimetric method for the determination of endo-1,4-β-xylanase in any sample type including crude enzyme extracts, fermentation broths or commercial enzyme preparations

(1) 3-Ketobutylidene-GX5-β-PNP + H2O → Blocked-GXY + X(5-Y)-β-PNP

(2) X(5-Y)-β-PNP + H2O → D-xylose + PNP

(alkaline solution)
(3) PNP → phenolate ion (yellow colour)
Note: PNP = 4-nitrophenol

Kit size:
K-XylX6-1V 100 assays (manual) / 200 (auto-analyser)
K-XylX6-2V 200 assays (manual) / 400 (auto-analyser)

Method:                         Spectrophotometric at 400/405 nm
Total assay time:           10 min
Detection limit:                5.3 x 10-4 U/mL
Application examples:
Fermentation broths, industrial enzyme preparations, animal feed, biofuels research, barley
malt analysis
Method recognition:     Novel method