木聚糖酶M3[长枝木霉] endo-1,4-β-Xylanase M3 (Trichoderma longibrachiatum) 货号:E-XYTR3 Megazyme中文站

木聚糖酶M3[长枝木霉]

英文名:endo-1,4-β-Xylanase M3 (Trichoderma longibrachiatum)

货号:E-XYTR3

规格:8000 Units

High purity endo-1,4-beta-Xylanase M3 (T. longibrachiatum) for use in research, biochemical enzyme assays and in vitrodiagnostic analysis.

EC 3.2.1.8

From T. longibrachiatum. Electrophoretically homogeneous, pI 9.0). 
In 3.2 M ammonium sulphate.

Specific activity: 132 U/mg (40oC, pH 6.0, wheat flour arabinoxylan as substrate).

Stable at 4oC for > 4 years.

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Beta葡聚糖[大麦;中黏度] Beta-Glucan (Barley;Med Viscosity) 5g 货号:P-BGBM Megazyme中文站

Beta葡聚糖[大麦;中黏度]

英文名:Beta-Glucan (Barley;Med Viscosity) 5g

货号:P-BGBM

规格:5 grams

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 1. Which barley beta-glucan do you recommend for the glucanase assay? There are three kinds of barley beta-glucan availabale from Megazyme – high viscosity, medium viscosity and low viscosity.

For glucanase assay, we recommend the medium viscosity beta-glucan.  We now offer low, medium and high viscosity wheat arabinoxylans, and we think that the low viscosity material will be best (easiest) to use in the reducing-sugar assay.

2. Both substrates; barley beta-glucan and wheat arabinoxylan, are standardised to a specific viscosity, e.g. 23-24 cSt. Are the substrates adjusted to give this viscosity?

The substrates are enzymically treated to yield the required viscosity (20 ~ 30 cSt). Modification of the viscosity of beta-glucan is required for IOB viscometric malt beta-glucanase test (which works well).

3. I would like to vacuum dry the standards instead of measuring the moisture content. I wish to dry them at a temperature lower than used in the preparation in Megazyme. Would you please give me some suggestions?

We suggest that you dry the β-glucan powders further in a vacuum oven at about 50˚C.  This will lower the moisture content to approximately 1-2%.

4. I understand a specific polymer can be used for the assay of malt β-glucanase and celluloses. I would very much like to know which polymer this β-glucan is?

The polymer you require is barley beta-glucan (medium viscosity).  The beta-glucan that we supply is pure 1,3:1,4-beta-D-glucan.  Barley β-glucan is also susceptible to hydrolysis by cellulase.

5. Although not specified on the beta-glucan data sheet, is the ratio of 1-3 to 1-4 bonds measured? If so, what is the ratio and would you expect it to remain standardised over a number of different batches?

The content of 1,3 bonds in barley beta-glucan is about 32% (from literature).  We would not expect this to change much (if at all) over different batches.

6. We have measured the molecular weight of beta-glucan originating from barley ordered from your company. Can you please tell us which method have you used for measuring molecular weight?

The MW’s were determined by Multiangle laser light scattering technique.

7. I have purchased barley beta-glucan (lot 30108) and carob galactomannan low viscosity (lot 30702) and would like to know what else there might be in these substrates.

Barley beta-glucan lot 30108 would contain about 3-4% arabinoxylan (this was produced in 1993).  Material supplied post 1995 contains < 0.5% arabinoxylan.  Carob galactomannan is quite pure (> 96%).

8. Low, Medium, High Viscosity β-Glucans, are they naturally occurring at these MW’s or are the MW fractions obtained by some other process?

The high molecular weight beta-glucan is the naturally occurring; this is enzymically modified to give the other viscosities. 

33-α-L-阿糖呋喃-xylotetraose(XA3XX) 33-α-L-Arabinofuranosyl-xylotetraose (XA3XX) 货号:O-XA3XX Megazyme中文站

33-α-L-阿糖呋喃-xylotetraose(XA3XX)

英文名:33-α-L-Arabinofuranosyl-xylotetraose (XA3XX)

货号:O-XA3XX

规格:30 mg

33-α-L-Arabinofuranosyl-xylotetraose (XA3XX)

CAS: 84666-93-3
Molecular Formula: C25H42O21
Molecular Weight: 678.6
Purity: > 95%

High purity 33-α-L-arabinofuranosyl-xylotetraose (XA3XX) for use in research, biochemical enzyme assays and in vitro diagnostic analysis. It can be used as an analytical standard or as a substrate to help characterise the activities of arabinoxylan degrading enzymes including endo-xylanase, β-xylosidase and α-L-arabinofuranosidase. This compound was prepared by the controlled enzymatic hydrolysis of wheat arabinoxylan.

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木聚糖酶[混联] endo-1,4-β-Xylanase (Cellvibrio mixtus) 货号:E-XYNBCM Megazyme中文站

木聚糖酶[混联]

英文名:endo-1,4-β-Xylanase (Cellvibrio mixtus)

货号:E-XYNBCM

规格:1500 Units

High purity recombinant endo-1,4-beta-Xylanase (Cellvibrio mixtus) for use in research, biochemical enzyme assays 
and in vitro diagnostic analysis.

EC 3.2.1.8 
CAZy Family: GH10

Recombinant. Catalytic domain of Xyn10B from Cellvibrio mixtus. 
In 3.2 M ammonium sulphate.

Specific activity: ~ 25 U/mg (40oC, pH 6.5 on wheat arabinoxylan); ~ 45 U/mg (50oC, pH 6.5 on wheat arabinoxylan).

Store at 4°C.

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L-鼠李糖检测试剂盒 L-Rhamnose Assay Kit 货号:K-RHAMNOSE Megazyme中文站

L-鼠李糖检测试剂盒

英文名:L-Rhamnose Assay Kit

货号:K-RHAMNOSE

规格:50 / 100 assays (manual) / 550 assays

This product (K-RHAMNOSE) supersedes the original L-Rhamnose Assay Kit (K-RHAM) which has been discontinued. K-RHAMNOSE provides a more rapid reaction (~ 5 min.) and much improved reagent stability compared to the previous kit.
The L-Rhamnose test kit is a simple, rapid, reliable and accurate method for the measurement of L-rhamnose in plant extracts, culture media/supernatants and other materials.
Suitable for manual, auto-analyser and microplate formats.

UV-method for the determination of L-Rhamnose in hydrolysates
of plant material, polysaccharides, culture media / supernatants
and other materials. Suitable for use with manual, microplate
and auto-analyser formats

Principle:
(L-rhamnose dehydrogenase)
(1) L-Rhamnose + NAD+ → L-rhamno-1,4-lactone + NADH + H+

Kit size: 50 / 100 assays (manual) / 550 (microplate)
/ 550 (auto-analyser)
Method: Spectrophotometric at 340 nm
Reaction time: ~ 5 min at 25°C or ~ 4 min at 37°C
Detection limit: ~ 1.2 mg/L
Application examples:
Hydrolysates of plant material and polysaccharides, culture media /
supernatants and other materials
Method recognition: Novel method

Advantages

  • Very cost effective
  • All reagents stable for > 2 years after preparation
  • Only test kit available
  • Simple format
  • Rapid reaction (~ 5 min at 25°C or ~ 4 min at 37°C)
  • Mega-Calc™ software tool is available from our website for hassle-free raw data processing
  • Standard included
  • Suitable for manual, microplate and auto-analyser formats

 

 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. Sometimes a negative absorbance change is obtained for the blank samples, is this normal? Should the real value (negative absorbance change) or “0” be used in the calculation of results?

Sometimes the addition of the last assay component can cause a small negative absorbance change in the blank samples due to a dilution effect and in such cases it is recommended that the real absorbance values be used in the calculation of results.

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. Can the sensitivity of the kit assay be increased?

For samples with low concentrations of analyte the sample volume used in the kit assay can be increased to increase sensitivity. When doing this the water volume is adjusted to retain the same final assay volume. This is critical for the manual assay format because the assay volume and sample volume are used in the calculation of results.

Q5. How much sample should be used for the clarification/extraction of my sample?

The volume/weight of sample and total volume of the extract can be modified to suit the sample. This will ultimately be dictated by the amount of analyte of interest in the sample and may require empirical determination. For low levels of analyte the sample:extract volume ratio can be increased (i.e. increase the sample and/or decrease the total extraction volume).

Alternatively, for samples with low concentrations of analyte, a larger sample volume can be added to the kit assay. When altering the sample volume adjust the distilled water volume added to the assay accordingly so that the total assay volume is not altered.

Q6. Can the test kit be used to measure biological fluids and what sample preparation method should be used?

The kit assay may work for biological fluids assuming that inositol is present above the limit of detection for the kit after any sample preparation (if required). Centrifugation of the samples and use of the supernatant directly in the kit assay (with appropriate dilution in distilled water) may be sufficient. However, if required a more stringent sample preparation method may be required and examples are provided at the following link:http://www.megazyme.com/docs/analytical-applications-downloads/biological_samples_111109.pdf?sfvrsn=2

The test kit has not been tested using biological fluids as samples because it is not marketed or registered as a medical device. This will therefore require your own validation.

Q7. Can the manual assay format be scaled down to a 96-well microplate format?

The majority of the Megazyme test kits are developed to work in cuvettes using the manual assay format, however the assay can be converted for use in a 96-well microplate format. To do this the assay volumes for the manual cuvette format are reduced by 10-fold. The calculation of results for the manual assay format uses a 1 cm path-length, however the path-length in the microplate is not 1 cm and therefore the MegaCalc spreadsheet or the calculation provided in the kit booklet for the manual format cannot be used for the micropalate format unless the microplate reader being used can.

There a 3 main methods for calculation of results using the microplate format:

  1. The easiest method is to use a microplate reader that has a path-length conversion capability (i.e. the microplater reader can detect the path-length of each well and convert the individual readings to a 1 cm path-length). This will allow values to be calculated using the MegaCalc calculation software which can be found where the product is located on the Megazyme website.
  2. Perform a standard curve of the analyte on each microplate that contains test samples and calculate the result of the test samples from the calibration curve (concentration of analyte versus absorbance).
  3. Perform a standard curve of the analyte in both the cuvette format (i.e. with a 1 cm path-length) and the 96-well microplate format and use these results to obtain a mean conversion factor between the cuvette values and the microplate values. Subsequent assays in the microplate format can then be converted from the calculated conversion factor.

Q8. How can I work out how much sample to extract and what dilution of my sample should be used in the kit assay?

Where the amount of analyte in a liquid sample is unknown, it is recommended that a range of sample dilutions are prepared with the aim of obtaining an absorbance change in the assay that is within the linear range.
Where solid samples are analysed, the weight of sample per volume of water used for sample extraction/preparation can be altered to suit, as can the dilution of the extracted sample prior to the addition of the assay, as per liquid samples.

Q9. I have some doubts about the appearance/quality of a kit component what should be done?

If there are any concerns with any kit components, the first thing to do is to test the standard sample (control sample) that is supplied with the kit and ensure that the expected value (within the accepted variation) is obtained before testing any precious samples. This must be done using the procedure provided in the kit booklet without any modifications to the procedure. If there are still doubts about the results using the standard sample in the kit then send example results in the MegaCalc spread sheet to your product supplier (Megazyme or your local Megazyme distributor).

Q10. Can oligosaccharides or polysaccharides be measured using the kit assay?

The kit assay will only measure the non-covalently linked monosaccharide.

Oligosaccharides or polysaccharides can be measured after hydrolysis to the monosaccharide. Generally acid hydrolysis can be achieved by boiling the oligo/polysaccharide in 1.3 M HCl for 1 h. It is recommended that scientific literature is consulted for information on hydrolysis conditions for the particular oligo/polysaccharide that is being measured.

Q11. Must the minimum absorbance change for a sample always be at least 0.1?

No. The 0.1 change of absorbance is only a recommendation. The lowest acceptable change in absorbance can is dictated by the analyst and equipment (i.e. pipettes and spectrophotometer) and therefore can be can be determined by the user. With accurate pipetting, absorbance changes as low as 0.02 can be used accurately.
If a change in absorbance above 0.1 is required but cannot be achieved due to low concentrations of analyte in a sample, this can be overcome by using a larger sample volume in the assay to increase the absorbance change and thereby increase sensitivity of the assay. When doing this the increased volume of the sample should be subtracted from the distilled water volume that is added to the assay so that the total assay volume is unaltered. The increase sample volume should also be accounted for when calculating final results. 

Q12. Can the sensitivity of the kit assay be increased?

Yes. Samples with the lower concentrations of analyte will generate a lower absorbance change. For samples with low concentrations of analyte, a larger sample volume can be used in the assay to increase the absorbance change and thereby increase sensitivity of the assay. When doing this the increased volume of the sample should be subtracted from the distilled water volume that is added to the assay so that the total assay volume is unaltered. The increase sample volume should also be accounted for when calculating final results.

Q13. When using this kit for quantitative analysis what level of accuracy and repeatability can be expected?

The test kit is extremely accurate – at Megazyme the quality control criteria for accuracy and repeatability is to be within 2% of the expected value using pure analytes.

However, the level of accuracy is obviously analyst and sample dependent.

Q14. Is it possible to add a larger volume then 2 μL of enzyme to the microplate assay? In some instances 2 μL can be difficult to pipette manually.

Yes, instead of adding 2 μL of enzyme suspension an alternative is to dilute the enzyme and add a larger volume to the microplate assay.

Dilute the assay buffer 10-fold with distilled water and use this as the diluent to dilute an aliquot of the enzyme suspension also by 10-fold. Instead of 2 μL, use 20 μL of the diluted enzyme in the microplate assay.

Alpha淀粉酶[苔藓杆菌] Alpha-Amylase (B. licheniformis) 货号:E-BLAAM-10ML Megazyme中文站

Alpha淀粉酶[苔藓杆菌]

英文名:Alpha-Amylase (B. licheniformis)

货号:E-BLAAM-10ML

规格:10mL – 3000 units/mL

High purity alpha-Amylase (B. licheniformis) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

EC 3.2.1.1
CAZy Family: GH13

Alpha-Amylase. From Bacillus licheniformis. Highly purified. For use in Megazyme Total Starch and Dietary Fiber methods. Stabilised solution.

Specific activity: 55 U/mg (40oC, pH 6.0, Ceralpha reagent as substrate).

Stable at 4oC for > 4 years.

Data booklets for each pack size are located in the Technical Resources tab.

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磷酸葡糖异构酶[枯草杆菌] Phosphoglucose isomerase (Bacillus subtilis) 货号:E-PGIBS-5KU Megazyme中文站

磷酸葡糖异构酶[枯草杆菌]

英文名:Phosphoglucose isomerase (Bacillus subtilis)

货号:E-PGIBS-5KU

规格:5000 units

High purity Phosphoglucose isomerase (B. subtilis) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

EC 5.3.1.9

From Bacillus subtilis. Electrophoretically homogeneous (MW 51,500). Several bands on isoelectric focusing (pI 4.8-5.0).
In 3.2 M ammonium sulphate.

Specific activity: 250 U/mg of protein (25oC, pH 7.6) or 483 U/mg of protein (40oC, pH 7.6).

Stable at 4oC for > 4 years.

Data booklets for each pack size are located in the Technical Resources tab.

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普鲁兰酶/极限醍醐精检测试剂盒 Pullulanase/Limit-Dextrinase Assay Kit (PULLG6 Method) 货号:K-PULLG6 Megazyme中文站

普鲁兰酶/极限醍醐精检测试剂盒

英文名:Pullulanase/Limit-Dextrinase Assay Kit (PULLG6 Method)

货号:K-PULLG6

规格:100 assays (manual)

PULLG6 assay for the measurement of pullulanase employs a water soluble defined substrate, namely 4,6-O-benzylidene-4-nitrophenyl-63-α-D-maltotriosyl-maltotriose (BPNPG3G3), coupled with the ancillary enzymes α-glucosidase and β-glucosidase. Upon hydrolysis of the substrate at the 1,6-α-linkage by pullulanase or limit-dextrinase, the released 4-nitrophenyl-β-maltotrioside is immediately hydrolysed to glucose and 4-nitrophenol by the concerted action of the α-glucosidase and β-glucosidase enzymes in the reagent mixture. The reaction is terminated and phenolate ions are developed by addition of dilute alkali. The absorbance is read at 400 nm and the value obtained correlates directly with pullulanase activity.

Colourimetric method for the determination of pullanase
or limit-dextrinase

Principle:
(pullulanase/limit-dextrinase)
(1) Benzylidene-G3-(α-1,6)-G3-β-PNP + H2O → Benzylidene-G3
+ G3-β-PNP

(thermostable α-glucosidase and β-glucosidase)
(2) G3-β-PNP + H2O → D-glucose + PNP

(alkaline solution)
(3) PNP → phenolate ion (yellow colour)

Note: PNP = 4-nitrophenol

Kit size: 100 assays
Method: Spectrophotometric at 400 nm
Total assay time: 10 min for pullanase preparations
30 min for malt extracts containing
limit-dextrinase
Detection limit: 0.18 U/mL for pullulanase preparations
(50-fold dilution)
0.01 U/g for limit dextrinase in milled malt
Application examples: Assay of microbial pullulanase preparations
Measurement of limit-dextrinase in
malt extracts
Method recognition: Novel method

Advantages

  • High sensitivity
  • Suitable for manual and auto-analyser formats
  • No transglycosylation interference
  • Very cost effective
  • All reagents stable for > 1 year after preparation
  • Very specific

  • Simple format

  • Standard included

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六乙酰壳六糖 Hexaacetyl-Chitohexaose- 10mg 货号:O-CHI6 Megazyme中文站

六乙酰壳六糖

英文名:Hexaacetyl-Chitohexaose- 10mg

货号:O-CHI6

规格:10 mg

CAS: 38854-46-5
Molecular Formula: C48H80N6O31
Molecular Weight: 1237.2
Purity: > 90%

High purity Hexaacetyl-chitohexaose for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

Prepared from chitin.

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Beta淀粉酶[大麦] Beta-Amylase (Barley; liquid) 50KU 货号:E-BARBL-50KU Megazyme中文站

Beta淀粉酶[大麦]

英文名:Beta-Amylase (Barley; liquid) 50KU

货号:E-BARBL-50KU

规格:50000 units

High purity beta-Amylase (Barley) liquid enzyme for use in research, biochemical enzyme assays and in vitro diagnostic analysis.
EC 3.2.1.2
CAZy Family: GH14
From barley flour. Crystalline.
In 3.2 M ammonium sulphate.
Specific activity: ca. 620 U/mg (40oC, pH 6.0, soluble starch as substrate).
Stable at 4oC for > 4 years.
Powder enzyme form (2000°L) is for use in AACC and ASBC α-amylase assay procedures (see E-BARBP).
Data booklets for each pack size are located in the Technical Resources tab.

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异淀粉酶[糖原6-葡萄糖苷酶] Isoamylase (Glycogen 6-glucanohydrolase) 货号:E-ISAMY Megazyme中文站

异淀粉酶[糖原6-葡萄糖苷酶]

英文名:Isoamylase (Glycogen 6-glucanohydrolase)

货号:E-ISAMY

规格:600 Units

High purity Isoamylase (Glycogen 6-glucanohydrolase) for use in research, biochemical enzyme assays and in vitrodiagnostic analysis.

EC 3.2.1.68 
CAZy Family: GH13

From Pseudomonas sp. Electrophoretically homogeneous.
In 3.2 M ammonium sulphate.

Specific activity: 280 U/mg (40oC, pH 4.0, oyster glycogen) (equivalent to 3 MU Sigma Units/mg).

Stable at 4oC for > 4 years.

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六乙酰壳六糖 Hexaacetyl-Chitohexaose- 10mg 货号:O-CHI6 Megazyme中文站

六乙酰壳六糖

英文名:Hexaacetyl-Chitohexaose- 10mg

货号:O-CHI6

规格:10 mg

CAS: 38854-46-5
Molecular Formula: C48H80N6O31
Molecular Weight: 1237.2
Purity: > 90%

High purity Hexaacetyl-chitohexaose for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

Prepared from chitin.

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外切-1,3 – β-D-葡聚糖酶(米曲霉)(重组) exo-1,3-β-D-Glucanase (Aspergillus oryzae) (Recombinant) 货号:E-EXG5AO Megazyme中文站

外切-1,3 – β-D-葡聚糖酶(米曲霉)(重组)

英文名:exo-1,3-β-D-Glucanase (Aspergillus oryzae) (Recombinant)

货号:E-EXG5AO

规格:500 Units at 40°C

High purity exo-1,3-beta-Glucanase (Aspergillus oryzae) (Recombinant) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

EC 3.2.1.58 
CAZy Family: GH5

Glucan 1,3-beta-glucosidase
3-beta-D-glucan glucohydrolase

Recombinant from Aspergillus oryzae.
In 3.2 M ammonium sulphate.

Specific activity: ~ 370 U/mg (50oC, pH 5.0 on laminarin); ~ 280 U/mg (40oC, pH 5.0 on laminarin).
Stability: > 4 years at 4oC.

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Azo-木聚糖(桦木) Azo-Xylan (Birchwood) 100ml 2 vials 货号:S-AXBL Megazyme中文站

Azo-木聚糖(桦木)

英文名:Azo-Xylan (Birchwood) 100ml 2 vials

货号:S-AXBL

规格:2 x 100 mL (1% w/v)

High purity dyed and crosslinked soluble Azo-Xylan (Birchwood) for the measurement of enzyme activity, for research, biochemical enzyme assays and in vitro diagnostic analysis.

Substrate for the specific assay of endo-1,4-ß-D-xylanase.

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普鲁兰酶M1[植生克雷伯氏菌] Pullulanase M1 (Klebsiella planticola) 货号:E-PULKP Megazyme中文站

普鲁兰酶M1[植生克雷伯氏菌]

英文名:Pullulanase M1 (Klebsiella planticola)

货号:E-PULKP

规格:700 Units

High purity Pullulanase M1 (K. planticola) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

EC 3.2.1.41 
CAZy Family: GH13

From Klebsiella planticola. Electrophoretically homogeneous.
In 3.2 M ammonium sulphate.

Specific activity: 34 U/mg (40oC, pH 5.0, 1% pullulan). 

Stable at 4oC for > 4 years. 
Recommended pullulanase for research on starch structure.

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蛋白酶[枯草杆菌][对地衣芽孢杆菌] Protease Subtilisin A (from Bacillus licheniformis) Powder 货号:E-BSPRPD Megazyme中文站

蛋白酶[枯草杆菌][对地衣芽孢杆菌]

英文名:Protease Subtilisin A (from Bacillus licheniformis) Powder

货号:E-BSPRPD

规格:1 gram powder

High purity Protease (Subtilisin A from B. licheniformis) (Powder) for use in research, biochemical enzyme assays and 
in vitro
 diagnostic analysis.

EC 3.4.21.14

Protease.

From Bacillus licheniformis. Highly purified. Powder form. For use in Megazyme Total Dietary Fiber test method. 

Specific activity: > 10 U/mg of protein; (40oC, pH 8.0, casein as substrate). 

Stable at -20oC for > 4 years.

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麦芽Beta葡聚糖酶和纤维素内切酶检测片剂 (200) Beta-Glucazyme (100mg) 1000 Tablets 货号:T-BGZ-200T Megazyme中文站

麦芽Beta葡聚糖酶和纤维素内切酶检测片剂 (200)

英文名:Beta-Glucazyme (100mg) 1000 Tablets

货号:T-BGZ-200T

规格:200 Tablets

High purity dyed and crosslinked beta-Glucazyme tablets for the measurement of enzyme activity, for research, biochemical enzyme assays and in vitro diagnostic analysis.

RACI Standard Method. For the assay of malt ß-glucanase and endo-cellulase. Containing AZCL-Barley ß-glucan.

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甘油检测试剂盒 Glycerol GK Assay Kit 货号:K-GCROLGK Megazyme中文站

甘油检测试剂盒

英文名:Glycerol GK Assay Kit

货号:K-GCROLGK

规格:70 assays (manual) /700 assays (microplate

The Glycerol GK test kit is a simple, reliable and accurate method for the measurement and analysis of glycerol in beverages, foodstuffs and other material. Based on use of ADP-glucokinase and increase in absorbance on conversion of NAD+ to NADH.
Extended cofactors stability. Dissolved cofactors stable for > 1 year at 4oC.
Suitable for manual, auto-analyser and microplate formats.

UV-method for the determination of Glycerol in foodstuffs,
beverages and other materials

Principle:
(glycerokinase)
(1) Glycerol + ATP → L-glycerol-3-phosphate + ADP

(ADP-GK)
(2) ADP + D-glucose → G-6-P + AMP

(glucose-6-phosphate dehydrogenase)
(3) G-6-P + NAD+ → gluconate-6-phosphate + NADH + H+

Kit size: 70 assays (manual) / 700 (microplate)
/ 600 (auto-analyser)
Method: Spectrophotometric at 340 nm
Reaction time: ~ 7 min
Detection limit: 0.37 mg/L
Application examples:
Wine (and grape juice), beer, spirits, vinegar, marzipan, fruit juices,
soft drinks, toothpaste, honey, tobacco, paper (and cardboard),
cosmetics, pharmaceuticals, soap and other materials (e.g. biological
cultures, samples, etc.)
Method recognition: Novel method

Advantages

  • Novel tablet format for increased stability
  • Very competitive price (cost per test)
  • All reagents stable for > 2 years as supplied
  • Very rapid reaction
  • Positive reaction (assay proceeds with an increase in absorbance)
  • Mega-Calc™ software tool is available from our website for hassle-free raw data processing
  • Standard included
  • Suitable for manual, microplate and auto-analyser formats

 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. Is the K-GCROLGK Assay Kit suitable for measurement using cell culture media samples?

Yes, assuming that the concentration of the analyte in the sample (after sample preparation) is above the limit of detection for the kit.  It may be sufficient to use the sample directly in the assay after clarification by centrifugation / filtering followed by dilution (if required) in distilled water. 

Q3. Is K-GCROLGK specific for glycerol?

K-GCROLGK is highly specific for glycerol.
Some compounds that are known not to react or interfere with the assay include:
Polyethylene glycol
Ethylene glycol
Propylene glycol 

Q4. Sometimes a negative absorbance change is obtained for the blank samples, is this normal? Should the real value (negative absorbance change) or “0” be used in the calculation of results?

Sometimes the addition of the last assay component can cause a small negative absorbance change in the blank samples due to a dilution effect and in such cases it is recommended that the real absorbance values be used in the calculation of results.

Q5. 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.

Q6. The pH of my sample is low (pH ~ 3.0), do I need to adjust this before I use the sample in the kit assay?

The final pH of the kit assay after the sample is added should not change from what it should be (as stated in the kit for the assay buffer). If it does change then the sample will require pH adjustment. In most cases the sample volume being used is low relative to the final assay volume and in this case the pH of the kit assay is unlikely to be affected.

Q7. How can I work out how much sample to extract and what dilution of my sample should be used in the kit assay?

Where the amount of analyte in a liquid sample is unknown, it is recommended that a range of sample dilutions are prepared with the aim of obtaining an absorbance change in the assay that is within the linear range.
Where solid samples are analysed, the weight of sample per volume of water used for sample extraction/preparation can be altered to suit, as can the dilution of the extracted sample prior to the addition of the assay, as per liquid samples.

Q8. Can you explain, step by step, how to follow the method and perform the kit assay?

For users who are not familiar with how to use the Megazyme tests kits then it is recommended that they follow this example, e.g. D-Fructose/D-Glucose Assay kit K-FRUGL (http://secure.megazyme.com/D-Fructose-D-Glucose-Assay-Kit):

1. The kit components are listed on pages 2-3 of the kit booklet.
2. Prepare the kit reagents as described on page 3.
3. For separate measurements of glucose and fructose follow procedure A on page 4.
4. Pipette the volumes listed for water, sample, solution 1 and solution 2 into 3 mL, 1 cm pathlength cuvettes. Duplicate sample assays and duplicate blanks are recommended. Mix the contents of each cuvette by inversion (seal the cuvette using parafilm or a plastic cuvette cap – do not use a finger) then after ~3 min record the first absorbance reading of each cuvette at 340 nm (this is reading A1).
5. Then add suspension 3 and mix the contents of each cuvette by inversion. Incubate for 5 minutes then record the absorbance reading of each cuvette at 340 nm (this is reading A2). NB. It is essential that the reaction is compete. To assess this, record the absorbances at ~ 2 minute intervals and until the absorbance plateaus. A stable absorbance indicates that the reaction is complete. If the absorbance continues to increase then continue to record absorbances until it plateaus and only then record absorbance reading A2.
6. Then add suspension 4 and mix the contents of each cuvette by inversion. Incubate for 5 minutes then take absorbance reading of each cuvette at 340 nm (this is reading A3). NB. As above, assess that the reaction has completed by take subsequent readings at ~2 min intervals.
7. For simple, automated results analysis, input the absorbance readings (A1, A2, A3) for samples and blanks into the 
K-FRUGL MegaCalc.

To ensure that the assay is working, and being performed correctly it is recommend that the test is performed using the standard sample that is provided with the kit and to obtain the expected values before proceeding to test real samples.
It is recommend that new users also watch 
this video which highlights how to perform the assays.
Many of the other Megazyme test kits follow a similar format.

Q9. I have some doubts about the appearance/quality of a kit component what should be done?

If there are any concerns with any kit components, the first thing to do is to test the standard sample (control sample) that is supplied with the kit and ensure that the expected value (within the accepted variation) is obtained before testing any precious samples. This must be done using the procedure provided in the kit booklet without any modifications to the procedure. If there are still doubts about the results using the standard sample in the kit then send example results in the MegaCalc spread sheet to your product supplier (Megazyme or your local Megazyme distributor).

Q10. Can the sensitivity of the kit assay be increased?

For samples with low concentrations of analyte the sample volume used in the kit assay can be increased to increase sensitivity. When doing this the water volume is adjusted to retain the same final assay volume. This is critical for the manual assay format because the assay volume and sample volume are used in the calculation of results.

Q11. How much sample should be used for the clarification/extraction of my sample?

The volume/weight of sample and total volume of the extract can be modified to suit the sample. This will ultimately be dictated by the amount of analyte of interest in the sample and may require empirical determination. For low levels of analyte the sample:extract volume ratio can be increased (i.e. increase the sample and/or decrease the total extraction volume).

Alternatively, for samples with low concentrations of analyte, a larger sample volume can be added to the kit assay. When altering the sample volume adjust the distilled water volume added to the assay accordingly so that the total assay volume is not altered.

Q12. Can the test kit be used to measure biological fluids and what sample preparation method should be used?

The kit assay may work for biological fluids assuming that inositol is present above the limit of detection for the kit after any sample preparation (if required). Centrifugation of the samples and use of the supernatant directly in the kit assay (with appropriate dilution in distilled water) may be sufficient. However, if required a more stringent sample preparation method may be required and examples are provided at the following link:http://www.megazyme.com/docs/analytical-applications-downloads/biological_samples_111109.pdf?sfvrsn=2

The test kit has not been tested using biological fluids as samples because it is not marketed or registered as a medical device. This will therefore require your own validation.

Q13. Can the manual assay format be scaled down to a 96-well microplate format?

The majority of the Megazyme test kits are developed to work in cuvettes using the manual assay format, however the assay can be converted for use in a 96-well microplate format. To do this the assay volumes for the manual cuvette format are reduced by 10-fold. The calculation of results for the manual assay format uses a 1 cm path-length, however the path-length in the microplate is not 1 cm and therefore the MegaCalc spreadsheet or the calculation provided in the kit booklet for the manual format cannot be used for the micropalate format unless the microplate reader being used can.

There a 3 main methods for calculation of results using the microplate format:

  1. The easiest method is to use a microplate reader that has a path-length conversion capability (i.e. the microplater reader can detect the path-length of each well and convert the individual readings to a 1 cm path-length). This will allow values to be calculated using the MegaCalc calculation software which can be found where the product is located on the Megazyme website.
  2. Perform a standard curve of the analyte on each microplate that contains test samples and calculate the result of the test samples from the calibration curve (concentration of analyte versus absorbance).
  3. Perform a standard curve of the analyte in both the cuvette format (i.e. with a 1 cm path-length) and the 96-well microplate format and use these results to obtain a mean conversion factor between the cuvette values and the microplate values. Subsequent assays in the microplate format can then be converted from the calculated conversion factor.

Q14. When using this kit for quantitative analysis what level of accuracy and repeatability can be expected?

The test kit is extremely accurate – at Megazyme the quality control criteria for accuracy and repeatability is to be within 2% of the expected value using pure analytes.

However, the level of accuracy is obviously analyst and sample dependent.

Q15. Is it possible to add a larger volume then 2 μL of enzyme to the microplate assay? In some instances 2 μL can be difficult to pipette manually.

Yes, instead of adding 2 μL of enzyme suspension an alternative is to dilute the enzyme and add a larger volume to the microplate assay.

Dilute the assay buffer 10-fold with distilled water and use this as the diluent to dilute an aliquot of the enzyme suspension also by 10-fold. Instead of 2 μL, use 20 μL of the diluted enzyme in the microplate assay.

Q16. Must the minimum absorbance change for a sample always be at least 0.1?

No. The 0.1 change of absorbance is only a recommendation. The lowest acceptable change in absorbance can is dictated by the analyst and equipment (i.e. pipettes and spectrophotometer) and therefore can be can be determined by the user. With accurate pipetting, absorbance changes as low as 0.02 can be used accurately.
If a change in absorbance above 0.1 is required but cannot be achieved due to low concentrations of analyte in a sample, this can be overcome by using a larger sample volume in the assay to increase the absorbance change and thereby increase sensitivity of the assay. When doing this the increased volume of the sample should be subtracted from the distilled water volume that is added to the assay so that the total assay volume is unaltered. The increase sample volume should also be accounted for when calculating final results. 

Q17. Can the sensitivity of the kit assay be increased?

Yes. Samples with the lower concentrations of analyte will generate a lower absorbance change. For samples with low concentrations of analyte, a larger sample volume can be used in the assay to increase the absorbance change and thereby increase sensitivity of the assay. When doing this the increased volume of the sample should be subtracted from the distilled water volume that is added to the assay so that the total assay volume is unaltered. The increase sample volume should also be accounted for when calculating final results.

Q18. To measure fermentation samples contain high microbial cell density, is cell disruption required?

Cell disruption is only require to measure glycerol within microbial cells.

To measure glycerol in the extracellular media only then cell disruption is not required and centrifugation of the sample may be sufficient, e.g.:

(a) Determination of glycerol in cell culture media/supernatants. In general, the concentration of glycerol in cell culture media/supernatants can be determined without any sample treatment (except clarification by centrifugation/filtering or dilution according to the dilution table, if necessary). Typically, no clarification or dilution is required, and a sample volume of 0.1 mL is satisfactory.

If interference is suspected then sample clarification/deproteinisation using carrez reagents or perchloric acid should be used (methods are provided in the kit booklet).

五乙酰壳五糖 Pentacetyl-Chitopentaose- 20mg 货号:O-CHI5 Megazyme中文站

五乙酰壳五糖

英文名:Pentacetyl-Chitopentaose- 20mg

货号:O-CHI5

规格:20 mg

CAS: 36467-68-2
Molecular Formula: C40H67N5O26
Molecular Weight: 1034.0
Purity: > 95%

High purity Pentaacetyl-chitopentaose for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

Prepared from chitin.

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谷氨酸草酰乙酸转氨酶[大肠杆菌] Glutamate oxaloacetate transaminase (E. coli) 货号:E-GOTEC Megazyme中文站

谷氨酸草酰乙酸转氨酶[大肠杆菌]

英文名:Glutamate oxaloacetate transaminase (E. coli)

货号:E-GOTEC

规格:5000

谷氨酸草酰乙酸转氨酶[大肠杆菌]

High purity Glutamate oxaloacetate transaminase (E. coli) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

EC 2.6.1.1
From E. coli. In 3.2 M ammonium sulphate. Electrophoretically homogeneous.
Specific activity: ~ 40 U/mg (25°C, pH 8.5).
Stable at 4°C for > 4 years

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转化酶 呋喃果糖苷酶(酵母) Invertase (fructofuranosidase) (yeast) 货号:E-INVRT Megazyme中文站

转化酶 呋喃果糖苷酶(酵母)

英文名:Invertase (fructofuranosidase) (yeast)

货号:E-INVRT

规格:100 mL; 200000 Units. 2000 U/mL

High purity Invertase (beta-Fructofuranosidase) (liquid) for use in research, biochemical enzyme assays and in vitrodiagnostic analysis.

EC 3.2.1.26

From yeast. Chromatographically purified. 
In 50% glycerol.

Specific activity: 300 U/mg protein (40oC, pH 4.5, 1% sucrose). 2,000 U/ml. 

Stable at 4oC for > 4 years.

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Alpha葡[萄]糖苷酶[麦芽糖酶][酵母] α-Glucosidase (yeast maltase) 货号:E-MALTS Megazyme中文站

Alpha葡[萄]糖苷酶[麦芽糖酶][酵母]

英文名:α-Glucosidase (yeast maltase)

货号:E-MALTS

规格:2000 Units

High purity alpha-Glucosidase (yeast maltase) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

EC 3.2.1.20

From yeast. Electrophoretically homogeneous. Ammonium sulphate suspension.

Specific activity: > 123U/mg (40oC, pH 6.8, pNP-α-Glucosidase as substrate).

Store at 4oC.
Stable for > 4 years at 4oC.

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酒石酸检测试剂盒 Tartaric Acid Assay Kit 货号:K-TART Megazyme中文站

酒石酸检测试剂盒

英文名:Tartaric Acid Assay Kit

货号:K-TART

规格:200 assays (manual) / 2000 assays (microplate)

Colourimetric method for the determination of myo-Inositol 
in various sample matrices

Principle:
                (myo-inositol dehydrogenase)
(1) myo-Inositol + NAD+ →
                   2,4,6/3,5-pentahydroxycyclohexanone + NADH + H+


                          (diaphorase)
(2) INT + NADH + H+ → NAD+ + INT-formazan

Kit size:                            50 assays
Method:                            Spectrophotometric at 492 nm
Reaction time:                  ~ 10 min
Detection limit:                 0.8 mg/L
Application examples:
Animal feeds, food, baby milk formulation and other materials
Method recognition:        Novel method

Q1. 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.

Q2. 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.

Q3. Can you explain, step by step, how to follow the method and perform the kit assay?

For users who are not familiar with how to use the Megazyme tests kits then it is recommended that they follow this example, e.g. D-Fructose/D-Glucose Assay kit K-FRUGL (http://secure.megazyme.com/D-Fructose-D-Glucose-Assay-Kit):

1. The kit components are listed on pages 2-3 of the kit booklet.
2. Prepare the kit reagents as described on page 3.
3. For separate measurements of glucose and fructose follow procedure A on page 4.
4. Pipette the volumes listed for water, sample, solution 1 and solution 2 into 3 mL, 1 cm pathlength cuvettes. Duplicate sample assays and duplicate blanks are recommended. Mix the contents of each cuvette by inversion (seal the cuvette using parafilm or a plastic cuvette cap – do not use a finger) then after ~3 min record the first absorbance reading of each cuvette at 340 nm (this is reading A1).
5. Then add suspension 3 and mix the contents of each cuvette by inversion. Incubate for 5 minutes then record the absorbance reading of each cuvette at 340 nm (this is reading A2). NB. It is essential that the reaction is compete. To assess this, record the absorbances at ~ 2 minute intervals and until the absorbance plateaus. A stable absorbance indicates that the reaction is complete. If the absorbance continues to increase then continue to record absorbances until it plateaus and only then record absorbance reading A2.
6. Then add suspension 4 and mix the contents of each cuvette by inversion. Incubate for 5 minutes then take absorbance reading of each cuvette at 340 nm (this is reading A3). NB. As above, assess that the reaction has completed by take subsequent readings at ~2 min intervals.
7. For simple, automated results analysis, input the absorbance readings (A1, A2, A3) for samples and blanks into the 
K-FRUGL MegaCalc.

To ensure that the assay is working, and being performed correctly it is recommend that the test is performed using the standard sample that is provided with the kit and to obtain the expected values before proceeding to test real samples.
It is recommend that new users also watch 
this video which highlights how to perform the assays.
Many of the other Megazyme test kits follow a similar format.

Q4. The pH of my sample is low (pH ~ 3.0), do I need to adjust this before I use the sample in the kit assay?

The final pH of the kit assay after the sample is added should not change from what it should be (as stated in the kit for the assay buffer). If it does change then the sample will require pH adjustment. In most cases the sample volume being used is low relative to the final assay volume and in this case the pH of the kit assay is unlikely to be affected.

Q5. How can I work out how much sample to extract and what dilution of my sample should be used in the kit assay?

Where the amount of analyte in a liquid sample is unknown, it is recommended that a range of sample dilutions are prepared with the aim of obtaining an absorbance change in the assay that is within the linear range.
Where solid samples are analysed, the weight of sample per volume of water used for sample extraction/preparation can be altered to suit, as can the dilution of the extracted sample prior to the addition of the assay, as per liquid samples.

Q6. I have some doubts about the appearance/quality of a kit component what should be done?

If there are any concerns with any kit components, the first thing to do is to test the standard sample (control sample) that is supplied with the kit and ensure that the expected value (within the accepted variation) is obtained before testing any precious samples. This must be done using the procedure provided in the kit booklet without any modifications to the procedure. If there are still doubts about the results using the standard sample in the kit then send example results in the MegaCalc spread sheet to your product supplier (Megazyme or your local Megazyme distributor).

Q7. Can the sensitivity of the kit assay be increased?

For samples with low concentrations of analyte the sample volume used in the kit assay can be increased to increase sensitivity. When doing this the water volume is adjusted to retain the same final assay volume. This is critical for the manual assay format because the assay volume and sample volume are used in the calculation of results.

Q8. How much sample should be used for the clarification/extraction of my sample?

The volume/weight of sample and total volume of the extract can be modified to suit the sample. This will ultimately be dictated by the amount of analyte of interest in the sample and may require empirical determination. For low levels of analyte the sample:extract volume ratio can be increased (i.e. increase the sample and/or decrease the total extraction volume).

Alternatively, for samples with low concentrations of analyte, a larger sample volume can be added to the kit assay. When altering the sample volume adjust the distilled water volume added to the assay accordingly so that the total assay volume is not altered.

Q9. Can the test kit be used to measure biological fluids and what sample preparation method should be used?

The kit assay may work for biological fluids assuming that inositol is present above the limit of detection for the kit after any sample preparation (if required). Centrifugation of the samples and use of the supernatant directly in the kit assay (with appropriate dilution in distilled water) may be sufficient. However, if required a more stringent sample preparation method may be required and examples are provided at the following link:http://www.megazyme.com/docs/analytical-applications-downloads/biological_samples_111109.pdf?sfvrsn=2

The test kit has not been tested using biological fluids as samples because it is not marketed or registered as a medical device. This will therefore require your own validation.

Q10. Can the manual assay format be scaled down to a 96-well microplate format?

The majority of the Megazyme test kits are developed to work in cuvettes using the manual assay format, however the assay can be converted for use in a 96-well microplate format. To do this the assay volumes for the manual cuvette format are reduced by 10-fold. The calculation of results for the manual assay format uses a 1 cm path-length, however the path-length in the microplate is not 1 cm and therefore the MegaCalc spreadsheet or the calculation provided in the kit booklet for the manual format cannot be used for the micropalate format unless the microplate reader being used can.

There a 3 main methods for calculation of results using the microplate format:

  1. The easiest method is to use a microplate reader that has a path-length conversion capability (i.e. the microplater reader can detect the path-length of each well and convert the individual readings to a 1 cm path-length). This will allow values to be calculated using the MegaCalc calculation software which can be found where the product is located on the Megazyme website.
  2. Perform a standard curve of the analyte on each microplate that contains test samples and calculate the result of the test samples from the calibration curve (concentration of analyte versus absorbance).
  3. Perform a standard curve of the analyte in both the cuvette format (i.e. with a 1 cm path-length) and the 96-well microplate format and use these results to obtain a mean conversion factor between the cuvette values and the microplate values. Subsequent assays in the microplate format can then be converted from the calculated conversion factor.

Q11. When using this kit for quantitative analysis what level of accuracy and repeatability can be expected?

The test kit is extremely accurate – at Megazyme the quality control criteria for accuracy and repeatability is to be within 2% of the expected value using pure analytes.

However, the level of accuracy is obviously analyst and sample dependent.

Q12. Is it possible to add a larger volume then 2 μL of enzyme to the microplate assay? In some instances 2 μL can be difficult to pipette manually.

Yes, instead of adding 2 μL of enzyme suspension an alternative is to dilute the enzyme and add a larger volume to the microplate assay.

Dilute the assay buffer 10-fold with distilled water and use this as the diluent to dilute an aliquot of the enzyme suspension also by 10-fold. Instead of 2 μL, use 20 μL of the diluted enzyme in the microplate assay.

Q13. Must the minimum absorbance change for a sample always be at least 0.1?

No. The 0.1 change of absorbance is only a recommendation. The lowest acceptable change in absorbance can is dictated by the analyst and equipment (i.e. pipettes and spectrophotometer) and therefore can be can be determined by the user. With accurate pipetting, absorbance changes as low as 0.02 can be used accurately.
If a change in absorbance above 0.1 is required but cannot be achieved due to low concentrations of analyte in a sample, this can be overcome by using a larger sample volume in the assay to increase the absorbance change and thereby increase sensitivity of the assay. When doing this the increased volume of the sample should be subtracted from the distilled water volume that is added to the assay so that the total assay volume is unaltered. The increase sample volume should also be accounted for when calculating final results. 

Q14. Can the sensitivity of the kit assay be increased?

Yes. Samples with the lower concentrations of analyte will generate a lower absorbance change. For samples with low concentrations of analyte, a larger sample volume can be used in the assay to increase the absorbance change and thereby increase sensitivity of the assay. When doing this the increased volume of the sample should be subtracted from the distilled water volume that is added to the assay so that the total assay volume is unaltered. The increase sample volume should also be accounted for when calculating final results.

半乳聚糖酶检测片剂 Galactazyme – 200 Tablets 货号:T-GLZ-200T Megazyme中文站

半乳聚糖酶检测片剂

英文名:Galactazyme – 200 Tablets

货号:T-GLZ-200T

规格:200 Tablets

High purity dyed and crosslinked Galactazyme tablets for the measurement of enzyme activity, for research, biochemical enzyme assays and in vitro diagnostic analysis.

For the assay of endo-1,4-ß-D-galactanase.Containing AZCL-Galactan potato.

半乳聚糖酶检测片剂

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