木聚糖酶检测底物

• 型   号：JKY/T-XYZ200
• 价   格：

木聚糖酶检测底物 型号:JKY/T-XYZ200

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木聚糖酶检测底物 型号:JKY/T-XYZ200

库号：M316808

外观 颜色 灰色片重约60毫克。
比重 不适用。
溶解度不溶于水，但膨胀，从而形成凝胶。
pH值 中性
气味 无
形态 片
稳定性 稳定 室温为10年以上

成分:木聚糖酶检测底物 型号:JKY/T-XYZ200
名称 比例
中德安联，小麦25％的阿拉伯木聚糖
乳糖 74.5％
硬脂酸镁（流平剂） 0.5％

Xylazyme （100 mg tablets）
For the assay of endo-1,4-ß-D-xylanase. [Containing AZCL-arabinoxylan （wheat）]. This substrate is the same as Xylazyme AX except for the larger tablet size （i.e. 100 mg cf. 60 mg） and slightly different assay format.

Catalogue Number: T-XYZ200
Content: 200 Tablets

Appearance Grey coloured tablets weighing approximay 60 mg.
Specific Gravity Not applicable.
Solubility in Water Not soluble, but swells to form a gel.
pH Value Neutral
Odour None
Form Tablet 型号:JKY/T-XYZ200
Stability Stable at room temperature for ten or more years
Ingredients Name CAS Proportion
AZCL-Wheat Arabinoxylan 25%
Lactose 74.5%
Magnesium stearate （flow agent） 0.5%

SUBSTRATE:
The substrate employed is azurine-crosslinked arabinoxylan （AZCLArabinoxylan）,
which is prepared by dyeing and cross-linking highly
purified wheat-flour arabinoxylan to produce a material which
hydrates in water but is water insoluble. Hydrolysis by endo-（1-4）-ß-
D-xylanase （xylanase） produces water soluble dyed fragments, and the
rate of release of these （increase in absorbance at 590 nm） can be
related directly to enzyme activity. The substrate is supplied
commercially in a ready-to-use tablet form, Xylazyme tablets.
BUFFER CONCENTRATE:
（Sodium acetate buffer, 200mM, pH 4.7） containing sodium
azide （0.02 %）.
Add 11.6 g of glacial acetic acid （1.05 g/mL） to 900 mL of distilled
water. Adjust the pH of this solution to 4.7 by the addition of 2 M
（8 g/100 mL） sodium hydroxide solution （approx. 50 mL is required）.
Adjust the volume to 1 litre. Add 0.2 g of sodium azide as a
preservative.
EXTRACTION/DILUTION BUFFER:
（Sodium acetate buffer, 25 mM, pH 4.7） containing sodium
azide （0.02 %）.
Add 125 mL of extaraction buffer to 850 mL of distilled water and
add 0.2 g of sodium azide. Adjust the pH to pH 4.7 by dropwise
addition of 2 M hydrochloric acid, and adjust the volume to 1 litre.
ENZYME EXTRACTION AND DILUTION:
Using a positive displacement dispenser, add 1 mL of liquid enzyme
preparation to 99.0 mL of extraction/dilution buffer （pH 4.7） and mix
thoroughly. Dilute an aliquot of this solution （original extract）
10-fold by transferring 0.5 mL to 4.5 mL of extarction/dilution buffer.
Mix thoroughly. Repeat this process of 10-fold dilution until a
concentration of enzyme suitable for assay is obtained. For example,
with the industrial enzyme preparation Laminex BG （from Trichoderma
sp.; Genencor International, U.S.A.） a further dilution of the original
extract of 200-fold is required.
1
NOTE:
Do not add the sodium azide until the pH is adjusted. Acidification
of sodium azide releases a poisonous gas.
With powder enzyme preparations, add 1.0 g of the material to
100 mL of extraction/dilution buffer and mix on a magnetic stirrer for
10 min, or until the sample is compley dispersed or dissolved.
Clarify the solution by centrifugation （1,000 g, 10 min） or filtration
through Whatman No. 1 （9 cm） filter circles. Dilute an aliquot of this
solution 10-fold by transferring 0.5 mL to 4.5 mL of extraction/
dilution buffer. Mix thoroughly. Repeat this process of
10-fold dilution until a concentration of enzyme suitable for assay is
obtained. For example, with the industrial enzyme preparation
Bioxylanase 10P （from Aspergillus niger; Kerry Ingredients, Cork,
Ireland） a further dilution of the original extract of 2000-fold is
required.
ASSAY PROCEDURE:
Pre-equilibrate a 1.0 mL aliquot of suitably diluted enzyme
preparation in buffer （25 mM, pH 4.7） at 40°C for 5 min. Add a
Xylazyme tablet to initiate the reaction. The tablet hydrates rapidly.
The suspension should not be stirred. Terminate the reaction after
exactly 10 min by adding 10.0 mL of Trizma Base solution （2 % w/v,
Sigma cat. no.T-1503） with vigorous stirring on a vortex mixer. Leave
the tube standing at room temperature for 4-5 min and stir the slurry
again. Filter the solution through a Whatman （9 cm） filter circle.
Prepare a substrate/enzyme blank by adding 10 mL of Trizma Base
solution to the enzyme solution before adding the Xylazyme tablet.
After adding the tablet, stir the tube vigorously and allow the tube to
stand at room temperature for approx. 10 min. Then filter the slurry
through Whatman No. 1 filter paper.
STANDARDISATION:
Standard curves relating the activity of purified Aspergillus niger
xylanase on wheat arabinoxylan and Xylazyme （Lots 40301 and
70805） are shown in Figure 1. Xylanase activity was standardised
using wheat arabinoxylan （10 mg/mL） in 100 mM sodium acetate
buffer （pH 4.7） as substrate, performing incubations at 40°C and
measuring increase in reducing sugar level using the Nelson/Somogyi
reducing sugar procedure