Alpha-amylase, inhibition

Preparations of BSA, asparaginase (aspa), alpha amylase (amy), and lysozyme (lyso) to which the indicated number of 1-thioglycopyranosides had been attached by amidi-nation. 6 Determined by the inhibition assay described in Ref. 97. c RIP = relative... 

Lo Piparo E, Scheib H, Frei N, Williamson G, Grigorov M, Chou CJ. 2008. Flavonoids for controlling starch digestion Structural requirements for inhibiting human alpha-amylase. J Med Chem 51 3555-3561. 

The inhibitor constants, Kj, may be determined by measuring the variation of v with [S] at different concentrations of the inhibitor. Lineweaver—Burk plots can then be used to find K/ from measurements made in the presence, and absence, of inhibitor (see Fig. 2 and Table I). The kinetics of the inhibition of such enzymes as alpha-amylase, hefo-amylase, and phosphorylase have been studied, and inhibitor constants evaluated. 

Heavy-metal ions, such as those of mercury, silver, copper, and lead inhibit alpha-amylases in general, mercury is more effective than copper or lead. fllphfl-Amylases from higher plants are also inhibited by ammonium molybdate and L-ascorbic acid. The mechanism of inhibition is not yet known. 

Estimations of and inhibition studies are, however, more valid, because determinations of absolute rates of bond scission are not necessary. The Michaelis constants for several alpha-amylases have been determined, and are shown in Table XI it may be seen that wide variations occur. For hog-pancreas alpha-amylase, it has been claimed that the value of depends on the degree of hydrolysis of the substrate this is probably true for all alpha-amylases when high degrees of hydrolysis are reached. 

Mammalian alpha-amylases are activated by monovalent anions, especially chloride. Equations, similar to those for enzyme inhibition (see p. 290), may be written for the formation of enzyme—activator complexes, and kinetic parameters may be derived. Dissociation constants of salivary alpha-amylase—anion complexes have been determined. ... 

An ethyl acetate extract of Sicilian sumac inhibited alpha-amylase, a glycoside hydrolase, indicating hypoglycemic activity of this extract. The IC50 was 28.7 jig/ml (Giancarlo et al. 2006). 

Etxeberria, U., de la Garza, A. L., Campion, J., Martinez, J. A. and Milagro, F. I., 2012. Antidiabetic effects of natural plant extracts via inhibition of carbohydrate hydrolysis enzymes with emphasis on pancreatic alpha amylase. Expert Opinion on Therapeutic Targets 16(3), 269-297. 

Mehrabadi, M., Bandani, A.R., Saadati, R (2010). Inhibition of Sunn pest, Eurygaster integriceps, alpha-amylases by alpha-amylase inhibitors (T-alpha-AI) from Triticale. Journal of Insect Science, Vol. 10, pp. 179-185, ISSN 1536-2442 Molinari, G. (2009). Natural products in drug discovery present status and perspectives. 

Yuldasheva, G.A., Zhidomirov, G.M., Ilin, A.I. (2011). A quantum-chemical model of the inhibition mechanism of viral DNA HIV-1 replication by Iodine complex compounds. Natural Science, Vol. 3, No. 7, pp. 573-579, ISSN 2150-4091 Zemke, K.J., Muller-Fahrnow, A., Jany, K. (1991). The three-dimensional structure of the bifunctional proteinase K/ alpha-amylase inhibitor from wheat (PK13) at 2.5 A resolution. PEES, Vol. 397, pp.240-242, ISSN 1742-4658... 

Gowri, P. M, Tiwaii, A. K, Ali, A. Z, Rao, J. M. Inhibition of alpha-glucosidase and amylase by bartogenic add isolated from Barringtonia racemosa Roxb. seeds. Phytothe-raphy Research. (2007). 

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