Contents of the Kit:
|| Enzyme B
||:2 tubes |
||:2 tubes |
||:1 ml x 2
|| Indicator solution
||:5 ml x 2 |
Storage Condition: 0-5°C
Shipping Condition: ambient temperature
Required Equipment and Materials
plate reader with 450 nm filter; 96-well culture plate, 2-20 μl, 20-200 μl, 100-1000 μl and multi-channel pipettes; 37ºC incubator, Disposable syringe (1 ml)
The kit is used for the determination of ACE inhibition activity. ACE works in the Renin-Angiotensin system, which is one of the mechanisms of blood pressure control, to convert Angiotensin I to the vasopressor Angiotensin II. This enzyme also contributes to elevated blood pressure due to its role in breaking down the antihypertensive peptide Bradykinin. In recent years, food and supplements containing ingredients that block ACE have received attention for their use in preventing high blood pressure. The conventional method of measuring ACE inhibition employs the synthetic substrate Hippuryl-His-Leu. Hippuric acid from the synthetic substrate is extracted with ethyl acetate, condensed, redissolved, and then read at an absorbance of 228 nm. This method is cumbersome and measurement is subjected to error due to residual ethyl acetate. ACE inhibition Assay Kit enzymatically detects 3-Hydroxybutyric acid (3HB), which is made from 3-Hydryoxybutyryl-Gly-Gly-Gly (3HB-GGG). Using a 96-well format, it is possible to test multiple samples at one time. In addition, there is no need to use harmful organic solvents, resulting in a safe, simple, and highly reproducible assay.
Fig. 1 Principle of the assay system to determine ACE activity or inhibition activity.
1) L. H. Lam, T. Shimamura, K. Sakaguchi, K. Noguchi, M. Ishiyama, Y. Fujimura and H. Ukeda, "Assay of angiotensin I-converting enzyme-inhibiting activity based on the detection of 3-Hydroxybutyric acid", Anal. Biochem., 2007, 364, 104.
2) L. H. Lam, T. Shimamura, S. Manabe, M. Ishiyama and H. Ukeda, "Assay of Angiotensin I-converting Enzyme-inhibiting Activity Based on the Detection of 3-Hydroxybutyrate with Water-soluble Tetrazolium Salt", Anal. Sci., 2008, 24, 1057.
3) C. C. Lau, N. Abdullah and A. S. Shuoib, "Novel angiotensin I-converting enzyme inhibitory peptides derived from an edible mushroom, Pleurotus cystidiosus O.K. Miller identified by LC-MS/MS", BMC Complement. Altern. Med., 2013,13, 313.
4) K. Yamaki, "Screening Research Methods for α-glucosidase Inhibitors and Angiotensin-converting Enzyme Inhibitors in Fermented Soybean Products and Fermented Milk Products", JARQ, 2014, 48, 41.
5) R. Nakabayashi, Z. Yang, T. Nishizawa, T. Mori and K. Saito, "Top-down Targeted Metabolomics Reveals a Sulfur-Containing Metabolite with Inhibitory Activity against Angiotensin-Converting Enzyme in Asparagus officinalis", J. Nat. Prod., 2015, 78(5), 1179.
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