阿拉伯聚糖检测试剂盒 Arabinan Assay Kit 货号：K-ARAB Megazyme中文站

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阿拉伯聚糖检测试剂盒

英文名：Arabinan Assay Kit

货号：K-ARAB

规格：100 assays per kit

The Arabinan test kit is suitable for the measurement and analysis of Arabinan in fruit juice concentrates.

 

 

Advantages

  • Very rapid reaction due to inclusion of galactose mutarotase (patented technology)
  • Very cost effective
  • All reagents stable for > 2 years after preparation
  • Only enzymatic kit available
  • Very specific
  • Simple format
  • Mega-Calc™ software tool is available from our website for hassle-free raw data processing
  • Standard included

 

UV-method for the determination of Arabinan in plant
materials and juices

Principle:
(endo-arabinanase + α-L-arabinofuranosidase)
(1) Arabinan + H2O → L-arabinose

(galactose mutarotase)
(2) α-L-Arabinose ↔ β-L-arabinose

(β-galactose dehydrogenase)
(3) β-L-Arabinose + NAD+ → L-arabinonic acid + NADH + H+

Kit size:                           100 assays
Method:                           Spectrophotometric at 340 nm
Reaction time:                  ~ 10 min
Detection limit:                1.3 mg/L
Application examples: 
Fruit juices and other materials
Method recognition:         Novel method

Q1. Should the pH of the sample be adjusted even for samples in acidic media?

The pH of the assay solution after the sample is added should be the same as that of the assay buffer that is supplied with the kit.
Low sample volumes (e.g. 0.1 mL) are not likely to affect the pH of the assay solution and therefore may not require pH adjustment.
Samples above 0.1 mL are more likely to affect the pH of the assay solution and therefore the pH of these samples should be adjusted as described in the data booklet, prior to addition to the assay.

Q2. I have purchased sugar beet arabinan plus rye and wheat flour arabinoxylans. I would like any information that you could provide on the structures of these polymers.

Sugar Beet Arabinan – this is a polymer of 1,5-α-L-linked arabinofuranose units which is highly substituted by 1,3- and (1-2) linked single a-L-arabinofuranose residues.  About 50% of 1,5 linked arabinosyl residues in the main chain are substituted by 1,3 or 1,2 linked arabinofuranosyl branches.
Rye/Wheat Arabinoxylan – These simply are composed of 1,4-β-D-linked xylan main chains (about 500-1000 residues); substituted by α-L-arabinofuranosyl residues linked 1,3-α or 1,2-α.  They differ in the extent of substitution by α-L-arabinofuranose.  They also contain some ferulic acid residues (linked to arabinose).

Q3. There is an issue with the performance of the kit; the results are not as expected.

If you suspect that the Megazyme test kit is not performing as expected such that expected results are not obtained please do the following:

  1. Ensure that you have tested the standard sample that is supplied with the Megazyme test kit.
  2. Send the results of the kit standard, blank samples and the results obtained for your sample,  in the relevant MegaCalc spreadsheet (if available) to Megazyme (cs@megazyme.com). Where available the relevant MegaCalc spreadsheet can be downloaded from where the product appears on the Megazyme website.
  3. State the kit lot number being used (this is found on the outside of the kit box).
  4. State which assay format was used (refer to the relevant page in the kit booklet if necessary).
  5. State exact details of any modifications to the standard procedure that is provided by Megazyme.
  6. State the sample type and describe the sample preparation steps if applicable.

Q4. What is the molecular weight of Arabinan (Polysaccharide)?

The molecular weight is approximately 15,000 daltons based on HPLC on Fractogel TSK G4000 PN.