淀粉總量HK檢測試劑盒 Total Starch HK Assay Kit 貨號:K-TSHK Megazyme中文站

淀粉總量HK檢測試劑盒

英文名: Total Starch HK Assay Kit

貨號:K-TSHK

規格:100 assays per kit

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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1,4-b-D-半乳糖內切酶[黑曲霉] endo-1,4-β-Galactanase (Aspergillus niger) 貨號:E-EGALN Megazyme中文站

1,4-b-D-半乳糖內切酶[黑曲霉]

英文名:endo-1,4-β-Galactanase (Aspergillus niger)

貨號:E-EGALN

規格:1000 Units

High purity endo-1,4-β-Galactanase (Aspergillus niger) for use in research, biochemical enzyme assays and in vitrodiagnostic analysis.

EC 3.2.1.89
CAZy Family: GH53
CAS: 58182-40-4

arabinogalactan endo-beta-1,4-galactanase; arabinogalactan 4-beta-D-galactanohydrolase

From Aspergillus niger.
In 3.2 M ammonium sulphate.

Specific activity: ~ 400 U/mg (40oC, pH 4.0 on potato galactan).

Stability: > 4 years at 4oC.

 

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

33-α-L-阿糖呋喃-xylotetraose(XA3XX)

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

貨號:O-XA3XX

規格: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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轉化酶(粉末)[酵母] Invertase Powder 貨號:E-INVPD-5G Megazyme中文站

轉化酶(粉末)[酵母]

英文名:Invertase Powder

貨號:E-INVPD-5G

規格:5 grams

High purity Invertase (powder) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

EC 3.2.1.26

β-Fructofuranosidase. Sucrase. Saccharase.

Specific activity: 300 U/mg of solid; 900 U/mg protein.

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

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阿拉伯樹膠七糖[純度>95%][粉] Arabinoheptaose (powder) – 15mg 貨號:O-AHP Megazyme中文站

阿拉伯樹膠七糖[純度>95%][粉]

英文名:Arabinoheptaose (powder) – 15mg

貨號:O-AHP

規格:15 mg

CAS: 190852-27-8
Molecular Formula: C35H58O29
Molecular Weight: 924.8
Purity: > 95%

High purity Arabinoheptaose (powder) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

Purity ~ 95%

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淀粉葡萄糖苷酶 Amyloglucosidase (Aspergillus niger) 貨號:E-AMGFR-100MG Megazyme中文站

淀粉葡萄糖苷酶

英文名:Amyloglucosidase (Aspergillus niger)

貨號:E-AMGFR-100MG

規格:100mg

High purity Amyloglucosidase (A. niger) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

EC 3.2.1.3 
CAZy Family: GH15

From Aspergillus niger. Lyophilised powder. Electrophoretically homogenous. 

High purity. Recommended for use in AOAC Method 997.08 (fructan). 

Specific activity: ~ 35 U/mg (40oC, pH 4.5, soluble starch as substrate).

Stable at -20oC for > 4 years.

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

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黃遞酶[大腸桿菌] Diaphorase (E. coli) 貨號:E-DIAEC Megazyme中文站

黃遞酶[大腸桿菌]

英文名:Diaphorase (E. coli)

貨號:E-DIAEC

規格:1000 Units

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

EC 1.8.1.4

From E. coli. 
In 3.2 M ammonium sulphate.

Specific activity: 69 U/mg (25oC, pH 9.0).

Stable at 4oC for > 2 years.

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麥芽淀粉酶標準液 Malt Amylase Standard 貨號:E-MAST Megazyme中文站

麥芽淀粉酶標準液

英文名:Malt Amylase Standard

貨號:E-MAST

規格:100 mL; α-amylase 950 U/mL;

High purity Malt Amylase Standard for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

A malt extract in which the levels of α-amylase and β-amylase have been standardised. The preparation is designed for use as a standard in the determination of α-amylase and dextrinising power.

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1,4-β-D- Cellotetraitol(硼氫化還原纖維四糖) 1,4-β-D-Cellotetraitol (borohydride reduced cellotetraose) 貨號:O-CTERD Megazyme中文站

1,4-β-D- Cellotetraitol(硼氫化還原纖維四糖)

英文名:1,4-β-D-Cellotetraitol (borohydride reduced cellotetraose)

貨號:O-CTERD

規格:50 mg

CAS: 5548-55-0
Molecular Formula: C24H44O21
Molecular Weight: 668.6
Purity: > 95%

High purity 1,4-β-D-Cellotetraitol (borohydride reduced cellotetraose) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

Tetrasaccharides from hydrolysis of cellulose and borohydride reduced.

Store at room temperature.

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乙酰基木聚糖酯酶檢測底物 Acetylxylan esterase (Orpinomyces sp.) 貨號:E-AXEAO-1KU Megazyme中文站

乙酰基木聚糖酯酶檢測底物

英文名:Acetylxylan esterase (Orpinomyces sp.)

貨號:E-AXEAO-1KU

規格:1000 units

High purity recombinant Acetylxylan esterase (Orpinomyces sp.) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

EC 3.1.1.72
CAZy Family: CE6
CAS: 188959-24-2/9000-82-2

acetylxylan esterase

Recombinant. From Orpinomyces sp.
In 3.2 M ammonium sulphate.

Specific activity: ~ 290 U/mg (40oC, pH 6.7 on 4-nitrophenyl acetate)

Stability: > 2 years at 4oC.

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

DESCRIPTION

Acetylxylan esterase (Orpinomyces sp.)

EC 3.1.1.72
CAZy Family: CE6
CAS: 188959-24-2 / 9000-82-2

Synonyms
acetylxylan esterase

Form:
In 3.2 M ammonium sulphate.

Stability:
> 2 years at 4oC.

Specific activity:
~ 290 U/mg (40oC, pH 6.7 on 4-nitrophenyl acetate).

Unit definition:
One Unit of acetylxylan esterase activity is defined as the amount of enzyme required to release one μmole of p-nitrophenol per minute from 4-nitrophenyl acetate in sodium phosphate buffer (100 mM), pH 6.7 at 40oC.

Specificity:
Catalyses the hydrolysis of acetyl groups from polymeric xylan, acetylated xylose, acetylated glucose, α-napthyl acetate and 4-nitrophenyl acetate but not from triacetylglycerol. Does not act on acetylated mannan or pectin.

Applications:
Applications established in carbohydrate research and biofuel industries.

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α-鼠李糖苷酶[來源于原核生物] α-Rhamnosidase (prokaryote) 貨號:E-RHAMS Megazyme中文站

α-鼠李糖苷酶[來源于原核生物]

英文名:α-Rhamnosidase (prokaryote)

貨號:E-RHAMS

規格:3000 Units at 50°C

High purity recombinant alpha-Rhamnosidase (prokaryote) for use in research, biochemical enzyme assays and in vitrodiagnostic analysis.

EC 3.2.1.40 
CAZy family: GH78

α-L-rhamnoside rhamnohydrolase.

Recombinant from a prokaryote. 
In 3.2 M ammonium sulphate. 

Specific activity: ~ 190 U/mg (50oC, pH 6.5 on p-nitrophenyl-α-L-rhamnoside)

Store > 2 years 4oC.

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木聚糖酶檢測底物(1000) Xylazyme (100mg) – 1000 Tablets 貨號:T-XYZ-1000T Megazyme中文站

木聚糖酶檢測底物(1000)

英文名:Xylazyme (100mg) – 1000 Tablets

貨號:T-XYZ-1000T

規格:1000 Tablets

High purity dyed and crosslinked Xylazyme (100 mg 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-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.

木聚糖酶檢測底物

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磷酸轉乙酰酶[枯草桿菌] Phosphotransacetylase (Bacillus subtilis) 貨號:E-PTABS Megazyme中文站

磷酸轉乙酰酶[枯草桿菌]

英文名:Phosphotransacetylase (Bacillus subtilis)

貨號:E-PTABS

規格:3000 Units

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

EC 2.3.1.8

Acetyl-CoA: orthophosphate acteyltransferase; Phosphate acetyltransferase.

Recombinant from B. subtilis. 
In 3.2 M ammonium sulphate. This enzyme is commonly used, in conjunction with 
acetate kinase, for the measurement of acetic acid.

Specific activity: 18,325 U/mg (25oC, pH 7.4).

Stable at 4oC for > 2 years. 

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葡萄糖-6-磷酸脫氫酶(大腸桿菌) Glucose 6-phosphate dehydrogenase (E. coli) 貨號:E-GPDHEC Megazyme中文站

葡萄糖-6-磷酸脫氫酶(大腸桿菌)

英文名:Glucose 6-phosphate dehydrogenase (E. coli)

貨號:E-GPDHEC

規格:5000 Units

High purity recombinant Glucose 6-phosphate dehydrogenase (E. Coli) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

EC 1.1.1.49

Recombinant from E. coli. 
In 3.2 M ammonium sulphate.
Supplied at ~ 1,250 U/mL. 

Specific activity: 172 U/mg (25oC, pH 7.6, D-glucose-6-phosphate).

Stable at 4oC for > 2 years.

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乳糖/蔗糖/D-葡萄糖檢測試劑盒 Lactose/Sucrose/D-Glucose Assay Kit 貨號:K-LACSU Megazyme中文站

乳糖/蔗糖/D-葡萄糖檢測試劑盒

英文名:Lactose/Sucrose/D-Glucose Assay Kit

貨號:K-LACSU

規格:100 assays of each per kit

分析物意義:常見加工食品組分,在某些情況下,精確的數值很重要,如 “無乳糖”產品 

Megazyme檢測試劑盒優點:K-LACGAR試劑盒反應快(室溫,5min)、試劑穩定

The Lactose/Sucrose/D-Glucose assay kit is suitable for the measurement and analysis of sucrose, lactose and D-glucose in flour mixtures and other materials.

Colourimetric method for the determination of Lactose, Sucrose
and D-Glucose in foodstuffs, beverages and other materials

Principle:
(invertase)
(1) Sucrose + H2O → D-glucose + D-fructose

(β-galactosidase)
(2) Lactose + H2O → D-glucose + D-galactose

(glucose oxidase)
(3) D-Glucose + H2O + O2 → D-gluconate + H2O2

(peroxidase)
(4) 2H2O2 + p-hydroxybenzoic acid + 4-aminoantipyrine →
quinoneimine + 4H2O

Kit size: 100 assays of each
Method: Spectrophotometric at 510 nm
Reaction time: ~ 60 min
Detection limit: 100 mg/L
Application examples:
Flours, beverages, dairy products, milk, foodstuffs containing milk,
cosmetics, pharmaceuticals and other materials (e.g. biological cultures,
samples, etc.)
Method recognition:
Used and accepted in food analysis

Advantages

  • Very competitive price (cost per test)
  • All reagents stable for > 12 months after preparation
  • Simple format
  • Very specific
  • Rapid reaction
  • Mega-Calc™ software tool is available from our website for hassle-free raw data processing
  • Standard included

 Q1. Would your kit K-LACSU (Lactose/Sucrose/D-Glucose) allow us to analyse for lactose in dairy by-products?

The K-LACSU kit will allow measurement of lactose in any materials.

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 your Lactose/Sucrose/D-Glucose Kit (K-LACSU) be used for measuring sucrose in wort and during fermentation?

The Lactose/Sucrose/D-Glucose Kit should work fine for wort.

Q4. With regard to your Lactose/Sucrose/D-Glucose Kit (K-LACSU), is it possible to measure lactose alone in a mixture of material in which sucrose and glucose could be present?

Yes, it is possible to specifically measure lactose in a mixture of sucrose, lactose and glucose.  Of course, it is also necessary to measure free glucose (i.e. with no added beta-galactosidase).

Q5. Would your kits – K-LACSU (Lactose/Sucrose/D-Glucose) and K-TSTA (Total Starch) allow us to analyse mixed feedstuff for total sugars?

The Lactose/Sucrose/D-Glucose Kit will allow measurement of sucrose, lactose and  glucose (not total sugars).  We can supply reagents separately for sucrose or lactose determination (or Glucose).

Q6. 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 ([email protected]). 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.

Q7. It states on the box that the kit should be stored at 0-5?C. The kit was not shipped at this temperature and the average temperature in our country is 30?C. Can we now use this kit or not?

The kits we supply are stable at room temperature for several months.  Thus we ship at room temperature.  When you get the kit, it should be stored as recommended and it will be stable for several years.  The kit will be perfectly fine at 30?C for the shipping time.

4-甲基 – α-吡喃甘露糖苷 4-Methylumbelliferyl-α-mannotetraoside 貨號:O-4MUAM4 Megazyme中文站

4-甲基 – α-吡喃甘露糖苷

英文名:4-Methylumbelliferyl-α-mannotetraoside

貨號:O-4MUAM4

規格:10 mg

Molecular Formula: C34H48O23
Molecular Weight: 824.7
Purity: 98%

High purity 4-Methylumbelliferyl-α-mannotetraoside for use in research, biochemical enzyme assays and in vitro diagnostic analysis. This is a potential colourimetric substrate for research into β-1,4-mannan degrading enzymes.

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α-L-阿拉伯呋喃糖苷B25(卵形類桿菌) α-L-Arabinofuranosidase B25 (Bacteroides ovatus) 貨號:E-ABFBO25 Megazyme中文站

α-L-阿拉伯呋喃糖苷B25(卵形類桿菌)

英文名:α-L-Arabinofuranosidase B25 (Bacteroides ovatus)

貨號:E-ABFBO25

規格:200 Units

High purity α-L-arabinofuranosidase (Bacteroides ovatus) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

EC 3.2.1.55
CAZy Family: GH43
CAS: 9067-74-7

non-reducing end alpha-L-arabinofuranosidase; alpha-L-arabinofuranoside non-reducing end alpha-L-arabinofuranosidase

Recombinant. From Bacteroides ovatus.
In 50% Glycerol.
Supplied at ~ 100 U/mL. 

Specific activity: ~ 16 U/mg protein (on wheat arabinoxylan) at pH 7.5 and 40oC.

Stability: > 4 years at -20oC.

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麥芽β-葡聚糖酶/β-葡聚糖酶檢測試劑盒 Malt β-Glucanase/Lichenase Assay Kit (MBG4 Method) 貨號:K-MBG4 Megazyme中文站

麥芽β-葡聚糖酶/β-葡聚糖酶檢測試劑盒

英文名:Malt β-Glucanase/Lichenase Assay Kit (MBG4 Method)

貨號:K-MBG4

規格:100 assays (manual) / 400 assays (auto-analyser)

alt β-glucanase:                  
100 assays (manual format) / 400 assays (auto-analyser format)
Lichenase:                            
100 / 200 assays (manual format) / 330 assays (auto-analyser format)

The MBG4 reagent contains a single substrate, namely 4,6-O-benzylidene-2-chloro-4-nitrophenyl-β-(31-β-D-cellotriosyl-glucoside) (BCNPBG4). The benzylidene acetal group prevents any hydrolytic action by exo-acting hydrolytic enzymes such as β-glucosidase or cellobiohydrolase. Mixed linkage 
β-glucanase (endo-1,3:1,4-β-glucanase) / lichenase (EC 3.2.1.73) acts specifically to release 2-chloro-4-nitrophenol (CNP) from this substrate. The rate of release of CNP is directly related to the β-glucanase/lichenase activity in a sample. The reaction is terminated and the phenolate colour is developed on addition of Tris buffer solution (pH = 10.0).

Note that the substrate is not hydrolysed by β-glucosidase or cellobiohydrolase. The substrate can be hydrolysed by certain endo-cellulases (e.g.Trichoderma sp.) but this does not result in an increase in absorbance.

Data calculators are located in the Documentation tab.

DESCRIPTION

Catalase (Aspergillus niger)

EC 1.11.1.16
CAS: 9001-05-2

Synonyms:
catalase; hydrogen-peroxide:hydrogen-peroxide oxidoreductase

Form:
In 3.2 M ammonium sulphate.
Supplied at ~ 18,000 U/mL.

Stability: 
> 2 years at 4oC.

Specific activity:
~ 4,960 U/mg protein (using A240 method) at pH 7.0 and 25oC.

Unit definition:
One Unit of catalase activity will decompose 1 micromole of H2O2 per minute at pH 7.0 and 25oC, while the H2O2 concentration falls from 10.3 mM to 9.2 mM. The rate of disappearance of H2O2 is followed by observing the rate of decrease in the absorbance at 
240 nm (A240).

Specificity:
Decomposition of hydrogen peroxide into water and oxygen.

 

Applications:
For use in research.

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琥珀酸/丁二酸檢測試劑盒 Succinic Acid Assay Kit 貨號:K-SUCC Megazyme中文站

琥珀酸/丁二酸檢測試劑盒

英文名:Succinic Acid Assay Kit

貨號:K-SUCC

規格:20 assays (manual) / 200 assays

The Succinic Acid test kit is suitable for the specific assay of succinic acid in wine, cheese, eggs, sauce and other food products.
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 Succinic Acid in foodstuffs,
feed, wine and other materials

Principle:
(succinyl-CoA synthetase)
(1) Succinic acid + ATP + CoA → ADP + succinyl-CoA + Pi

(pyruvate kinase)
(2) ADP + PEP → ATP + pyruvate

(L-lactate dehydrogenase)
(3) Pyruvate + NADH + H+ → NAD+ + L-lactic acid

Kit size: 20 assays (manual) / 200 (microplate)
/ 270 (auto-analyser)
Method: Spectrophotometric at 340 nm
Reaction time: ~ 6 min
Detection limit: 0.26 mg/L
Application examples:
Wine, fruit and vegetables, soy sauce, cheese, egg, egg products
and other materials (e.g. biological cultures, samples, etc.)
Method recognition:
Methods based on this principle have been accepted by EEC

Advantages

  • Very competitive price (cost per test)
  • All reagents stable for > 2 years as supplied
  • Very rapid reaction (even at room temperature)
  • 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. Is the Succinic Acid Assay Kit (K-SUCC) 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. 

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. 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.

Q4. 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 ([email protected]). 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.

Q5. 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.

Q6. 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.

Q7. 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.

Q8. 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).

Q9. 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.

Q10. 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.

Q11. 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.

Q12. 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.

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.

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半乳糖脫氫酶[土壤原核生物] Galactose dehydrogenase (soil prokaryote) 貨號:E-GALDH Megazyme中文站

半乳糖脫氫酶[土壤原核生物]

英文名:Galactose dehydrogenase (soil prokaryote)

貨號:E-GALDH

規格:200 Units

High purity recombinant Galactose dehydrogenase (soil prokaryote) for use in research, biochemical enzyme assays andin vitro diagnostic analysis.

EC 1.1.1.48

Recombinant from soil procaryote. This recombinant enzyme has been expressed in E. coli and purified by affinity chromatography. Electrophoretically homogeneous (MW 36,659). In 3.2 M ammonium sulphate.

Specific activity: 390 U/mg (25oC, pH 8.6, on galactose).

Stable at 4oC for > 2 years.

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淀粉葡萄糖苷酶 Amyloglucosidase (Aspergillus niger) 貨號:E-AMGFR-500MG Megazyme中文站

淀粉葡萄糖苷酶

英文名:Amyloglucosidase (Aspergillus niger)

貨號:E-AMGFR-500MG

規格:500mg

High purity Amyloglucosidase (A. niger) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

EC 3.2.1.3
CAZY Family: GH15
From Aspergillus niger. Lyophilised powder. Electrophoretically homogenous.

High purity. Recommended for use in AOAC Method 997.08 (fructan).

Specific activity: ~ 35 U/mg (40°C, pH 4.5, soluble starch as substrate).
Stable at -20°C for > 4 years.

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

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