for analysis of the inhibition activity of a component in foods

α-Glucosidase Inhibitory Activity Assay Kit

α-Glucosidase decomposes disaccharides into glucose, and increases blood glucose levels. Therefore, an increase in blood glucose can be suppressed by inhibiting the activity of α-Glucosidase. α-Glucosidase inhibitors have been discovered in various plants and their use is being explored for foods that will not cause an increase in blood glucose levels. This kit can, in combination with LabAssay™ Glucose (sold separately), measure the α-Glucosidase inhibitory effect of food products and the like.

Kit Components

Reagent name Pkg. size Number of the vial The principal ingredient
Enzyme 1 mL 2 α-Glucosidase
Buffer For 50 mL 2 Maleic Acid/Disodium Maleate
Substrate 1 For 20 mL 2 D-(+)-Maltose
Substrate 2 For 20 mL 2 Sucrose
Positive control 100 mg 1 Acarbose

Other supplies required

  • LabAssay™ Glucose
  • 96 well transparent microplate
  • Plate reader (with an absorption filter at 505 nm)
  • Micro-pipettes and pipette tips
  • Incubator (capable of keeping at 37°C)

Principle

Principle of the Assay

00421_img04.png

Procedure 1

Reagent Preparation

00421_img05.png

Preliminary Test for Determination of the Dilution Rate

Maltose Sucrose
Substrate solution Maltose solution 50 μL Sucrose solution 50 μL
Purified water 25 μL
Warm for 3 minutes at 37°C
Enzyme Diluted enzyme solution 25 μL
(Example: 5, 10, 20 fold diluent)
Diluted enzyme solution 25 μL
(Example: 1 (neat), 2.5, 5 fold dilution)
Mix, and keep accurately for 30 minutes at 37°C
Purified water 400 μL
Heat immediately in boiling water for 3 minutes, then keep in ice

【Quantification of glucose】
1. Aliquot 100 mL of enzyme reaction solution and diluted glucose standard solution (Concentration: 15, 10, 5, 2.5 mg/dL) into 96 wells microtiter plate, add 150 mL of chromogen reagent (included LabAssay™ Glucose), then mix thoroughly.
2. Warm for 10 minutes at 37°C, and measure the absorbance at 505 nm.
3. Determine the dilution rate as the amount of produced glucose becomes the following concentrations.
  For maltose: 10 mg/dL, For sucrose: 5 mg/dL

Note:
1) The package insert written in Japanese is attached. If you need the package insert in English, please contact us.
2) For the determination method of glucose, please refer the package insert of LabAssay™ Glucose.

Procedure 2

Reagent Preparation

Sample Preparation

Maltose Sucrose
Substrate solution Maltose solution 50 μL Sucrose solution 50μL
Sample or positive
control solution
(purified water as the negative control)
25 μL
Warm for 3 minutes at 37°C
Diluted enzyme solution Diluted enzyme solution 25 μL
(At the dilution rate determined
by the preliminary test)
Diluted enzyme solution 25 μL
(At the dilution rate determined
by the preliminary test)
Mix, and keep accurately for 30 minutes at 37°C
Purified water 400 μL
Heat immediately in boiling water for 3 minutes, then keep in ice

Blank Preparation

Maltose Sucrose
Substrate solution Maltose solution 50 μL Sucrose solution 50μL
Sample solution or purified water 25 μL
Purified water 400 μL
Diluted enzyme solution Diluted enzyme solution 25 μL
(At the dilution rate determined
by the preliminary test)
Diluted enzyme solution 25 μL
(At the dilution rate determined
by the preliminary test)
Heat immediately in boiling water for 3 minutes, then keep in ice

Glucose Quantification

Perform the same method using LabAssay™ Glucose as the preliminary test.

Calculation

IC50 Calculation

A) Set the yield of glucose of negative control as 100% α-Glucosidase activity. Calculate the specific activity of each concentration of samples.

B) Plot the concentration of sample/positive control at X-axis of semi logarithmic paper and specific activity of α-Glucosidase activity at Y-axis. The concentration of positive control should be the final concentration in enzyme reaction solution. Calculate the concentration at the point of the specific activity is 50% (IC50) from approximate curve.

00421_img06.png

Product List

  • Open All
  • Close All

α-Glucosidase Inhibitory Activity Assay Kit

LabAssay™ Glucose

Inhibitors

For research use or further manufacturing use only. Not for use in diagnostic procedures.

Product content may differ from the actual image due to minor specification changes etc.

If the revision of product standards and packaging standards has been made, there is a case where the actual product specifications and images are different.

+49-2131-311-271

Reception hours: Mon-Fri 9:00 - 15:00 (CET)For other hours than the above, please contact us via the inquiry form.