淀粉总量HK检测试剂盒 Total Starch HK Assay Kit 货号:K-TSHK Megazyme试剂盒

淀粉总量HK检测试剂盒

英文名: Total Starch HK Assay Kit

货号:K-TSHK

规格:100 assays per kit

市场价: 5300

A modification of AOAC Method 996.11 AACC Method 76-13.01 RACI Standard Method for the measurement and analysis of total starch in cereal flours and food products. This kit contains an improved α-amylase that allows the amylase incubations to be performed at pH 5.0 (as well as pH 7.0). The method has been further modified by adjusting the D-glucose determination to a hexokinase/glucose-6-phosphate dehydrogenase/NADP+ based format.

UV-method for the determination of Total Starch in grains,
animal feeds, foodstuffs and other materials

Principle:
(α-amylase, 100°C + DMSO)
(1) Starch granules + H2O → maltodextrins

(amyloglucosidase)
(2) Maltodextrins + H2O → D-glucose

(hexokinase)
(3) D-Glucose + ATP → G-6-P + ADP

(glucose-6-phosphate dehydrogenase)
(4) G-6-P + NADP+ → gluconate-6-phosphate + NADPH + H+

Kit size: 100 assays
Method: Spectrophotometric at 340 nm
Total assay time: ~ 90 min
Detection limit: 1-100% of sample weight
Application examples:
Cereal flours, food products and other materials
Method recognition:
AOAC (Method 996.11), AACC (Method 76-13.01), ICC (Standard
Method No. 168), and RACI (Standard Method)

Advantages

  • Very competitive price (cost per test)
  • All reagents stable for > 2 years after preparation
  • Simple format
  • Mega-Calc™ software tool is available from our website for hassle-free raw data processing
  • Standard included

 

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D-葡萄糖[HK法]检测试剂盒 D-Glucose HK Assay Kit 货号:K-GLUHK-110A Megazyme试剂盒

D-葡萄糖[HK法]检测试剂盒

英文名:D-Glucose HK Assay Kit

货号:K-GLUHK-110A

规格:110 assays (manual) / 1100 (microplate) / 1000 (auto-analyser)

市场价: 2862

分析物意义:常见食品组分,在某些情况下非常重要,如糖尿病产品   

Megazyme检测试剂盒优点:选择简单可用的方法,葡萄糖氧化酶/过氧化酶 /己糖激酶/6-磷酸葡萄糖脱氢酶。试剂稳定

High purity reagents for the assay of D-glucose in plant and food products. Can be used in combination with other Megazyme products that require glucose determination. Content:110 assays per kit

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

Principle:
(hexokinase)
(1) D-Glucose + ATP → G-6-P + ADP

(glucose-6-phosphate dehydrogenase)
(2) G-6-P + NADP+ → gluconate-6-phosphate + NADPH + H+

Kit size: (K-GLUHKR)
110 assays (manual) / 1100 (microplate)
/ 1000 (auto-analyser) or
(K-GLUHKL)
220 assays (manual) / 2200 (microplate)
/ 2000 (auto-analyser)
Method: Spectrophotometric at 340 nm
Reaction time: ~ 5 min
Detection limit: 0.66 mg/L
Application examples:
Wine, beer, fruit juices, soft drinks, milk, jam, dietetic foods, bakery
products, candies, fruit and vegetables, tobacco, cosmetics, pharmaceuticals
(e.g. infusions), feed, paper (and cardboard) and other materials (e.g.
biological cultures, samples, etc.)
Method recognition:
Methods based on this principle have been accepted by AOAC, EN,
NEN, NF, DIN, GOST, OIV, IFU, AIJN and MEBAK

Advantages

  • Very competitive price (cost per test)
  • All reagents stable for > 2 years after preparation
  • Rapid reaction
  • Mega-Calc™ software tool is available from our website for hassle-free raw data processing
  • Standard included
  • Extended cofactors stability
  • 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. Is it possible to detect glucose when it is bound via a glycosidic linkage?

No.  The K-GLUHKL test kit is specific for the measurement of “free” D-glucose.  It will not detect glucose that is bound by a glycosidic linkage to another sugar molecule. 

Q5. Can K-GLUHKL be used to measure glucose in biological samples?

Yes.  It is possible that biological samples may be used directly after appropriate sample dilution in distilled water, however some biological samples may require deproteinisation with perchloric acid prior to addition to the assay.  The deproteinisation method can be found at the following link on the Megazyme website: Deproteinisation Method

Dilution during sample preparation must be taken into account in the final calculation.

Q6. Can K-GLUHKL be used to measure glucose as a component of polysaccharides in plant material?

Yes.  Determination of D-glucose in polysaccharides and fibrous plant material: 
Mill plant material or polysaccharide to pass a 0.5 mm screen using a Retsch centrifugal mill, or similar.  Accurately weigh approx. 100 mg of material into a Corning screw-cap culture tube (16 x 125 mm).  Add 5 mL of 1.3 M HCl to each tube and cap the tubes.  Incubate the tubes at 100˚C for 1 h.  Stir the tubes intermittently during the incubation.  Cool the tubes to room temperature, carefully loosen the caps and add 5 mL of 1.3 M NaOH.  Quantitatively transfer the contents of the tube to a 100 mL volumetric flask using distilled water and adjust the volume to 100 mL with distilled water.  Mix thoroughly by inversion and filter an aliquot of the solution through Whatman No. 1 filter paper or centrifuge at 1,500 g for 10 min.  Typically, no further dilution is required and a sample volume of 0.1 mL is satisfactory. 

Q7. 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.

Q8. 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.

D-葡萄糖[HK法]检测试剂盒 D-Glucose HK Assay Kit 货号:K-GLUHK-220A Megazyme试剂盒

D-葡萄糖[HK法]检测试剂盒

英文名:D-Glucose HK Assay Kit

货号:K-GLUHK-220A

规格:220 assays (manual) / 2200 (microplate) / 2000 (auto-analyser)

市场价: 4982

分析物意义:常见食品组分,在某些情况下非常重要,如糖尿病产品   

Megazyme检测试剂盒优点:选择简单可用的方法,葡萄糖氧化酶/过氧化酶 /己糖激酶/6-磷酸葡萄糖脱氢酶。试剂稳定

High purity reagents for the assay of D-glucose in plant and food products. Can be used in combination with other Megazyme products that require glucose determination. Content:110 assays per kit

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

Principle:
(hexokinase)
(1) D-Glucose + ATP → G-6-P + ADP

(glucose-6-phosphate dehydrogenase)
(2) G-6-P + NADP+ → gluconate-6-phosphate + NADPH + H+

Kit size: (K-GLUHKR)
110 assays (manual) / 1100 (microplate)
/ 1000 (auto-analyser) or
(K-GLUHKL)
220 assays (manual) / 2200 (microplate)
/ 2000 (auto-analyser)
Method: Spectrophotometric at 340 nm
Reaction time: ~ 5 min
Detection limit: 0.66 mg/L
Application examples:
Wine, beer, fruit juices, soft drinks, milk, jam, dietetic foods, bakery
products, candies, fruit and vegetables, tobacco, cosmetics, pharmaceuticals
(e.g. infusions), feed, paper (and cardboard) and other materials (e.g.
biological cultures, samples, etc.)
Method recognition:
Methods based on this principle have been accepted by AOAC, EN,
NEN, NF, DIN, GOST, OIV, IFU, AIJN and MEBAK

Advantages

  • Very competitive price (cost per test)
  • All reagents stable for > 2 years after preparation
  • Rapid reaction
  • Mega-Calc™ software tool is available from our website for hassle-free raw data processing
  • Standard included
  • Extended cofactors stability
  • 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. Is it possible to detect glucose when it is bound via a glycosidic linkage?

No.  The K-GLUHKL test kit is specific for the measurement of “free” D-glucose.  It will not detect glucose that is bound by a glycosidic linkage to another sugar molecule. 

Q5. Can K-GLUHKL be used to measure glucose in biological samples?

Yes.  It is possible that biological samples may be used directly after appropriate sample dilution in distilled water, however some biological samples may require deproteinisation with perchloric acid prior to addition to the assay.  The deproteinisation method can be found at the following link on the Megazyme website: Deproteinisation Method

Dilution during sample preparation must be taken into account in the final calculation.

Q6. Can K-GLUHKL be used to measure glucose as a component of polysaccharides in plant material?

Yes.  Determination of D-glucose in polysaccharides and fibrous plant material: 
Mill plant material or polysaccharide to pass a 0.5 mm screen using a Retsch centrifugal mill, or similar.  Accurately weigh approx. 100 mg of material into a Corning screw-cap culture tube (16 x 125 mm).  Add 5 mL of 1.3 M HCl to each tube and cap the tubes.  Incubate the tubes at 100˚C for 1 h.  Stir the tubes intermittently during the incubation.  Cool the tubes to room temperature, carefully loosen the caps and add 5 mL of 1.3 M NaOH.  Quantitatively transfer the contents of the tube to a 100 mL volumetric flask using distilled water and adjust the volume to 100 mL with distilled water.  Mix thoroughly by inversion and filter an aliquot of the solution through Whatman No. 1 filter paper or centrifuge at 1,500 g for 10 min.  Typically, no further dilution is required and a sample volume of 0.1 mL is satisfactory. 

Q7. 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.

Q8. 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.

果聚糖[HK法]检测试剂盒 Fructan HK Assay Kit 货号:K-FRUCHK Megazyme试剂盒

果聚糖[HK法]检测试剂盒

英文名:Fructan HK Assay Kit

货号:K-FRUCHK

规格:50 assays per kit

市场价: 5194

分析物意义:许多食品如洋葱和种子中的常见组分

Megazyme检测试剂盒优点:方法新颖、反应快、试剂稳定 

The Fructan HK test kit is suitable for the specific measurement and analysis of all fructo-oligosaccharides (reducing and non-reducing) and of fructan polysaccharide.

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

Principle:
(sucrase + maltase)
(1) Sucrose + maltosaccharides + H2O → D-glucose + D-fructose

(exo-inulinase + endo-inulinase)
(2) Fructan + H2O → D-glucose + D-fructose

(hexokinase)
(3) D-Glucose + D-fructose + ATP → G-6-P + F-6-P + ADP

(glucose-6-phosphate dehydrogenase)
(4) G-6-P + NADP+ → gluconate-6-phosphate + NADPH + H+

(phosphoglucose isomerase)
(5) F-6-P ↔ G-6-P

Kit size: 50 assays
Method: Spectrophotometric at 340 nm
Total assay time: ~ 90 min
Detection limit: 1-100% of sample weight
Application examples:
Flours, plant materials (e.g. onion), food products and other materials
Method recognition:
This method is a modification of AOAC Method 999.03 and AACC
Method 32-32.01

Advantages

  • Very cost effective
  • All reagents stable for > 12 months after preparation
  • Fructan kits are available only from Megazyme
  • Simple format
  • Mega-Calc™ software tool is available from our website for hassle-free raw data processing
  • Standard included

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. 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.

Q5. 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).

Q6. 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.

Q7. 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.

Q8. 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.

Q9. 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.

Q10. 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.

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.

Megazyme 溶解淀粉 操作视频

Megazyme 试剂盒样品前处理准备操作视频

Megazyme果聚糖[HK法]试剂盒FructanHK操作视频(K-FRUCHK)