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S Kikumoto

Publications and source records attributed to S Kikumoto.

6 recordsLinked to original sources
PubMed1978

An improved assay method for amylase activity using an amylodextrin fraction as substrate.

A rapid and simple method for determination of amylase activity, by using a fraction of amylo-oligosaccharide (amylodextrin, 1) as substrate, is described. The sample solution is incubated with a solution of 1 and the substrate consumed is estimated by measuring the difference in absorbance at 460 nm. The Km value of 1 is about half that of starch. The homogeneity of 1 in its chemical structure and molecular weight facilitated the specification of amylase units according to the international definition. This procedure was applied for assay of human-serum amylase with excellent reproducibility. This method did not require a large dilution factor, as the standard curve showed a linear relationship over a wide range of amylase concentrations.

Amylases↗
PubMed1977

The TcO4-binding to human serum albumin --the stoichiometry and characteristics of the binding equilibrium.

The stoichiometry and the characteristics of the TcO4-binding equilibrium to human serum albumin were investigated by the use of 99TcO4-. Based on the Scatchard plots, the number of binding sites and the association constants were obtained at pH 7.38,6.04, 5.10, 4.18, 2.80 and 0.65, respectively. From the parameters at pH 7.38, it was estimated that 64% of TcO4- added was bounded to human serum albumin under physiological condition. Variance in the values at pH 7.38, 6.04 and 5.10 shows that these bindings are stabilized by electrostatic forces. Below pH 4.18, the number of binding sites increased and the association constants constants diminished. These phenomena may be attributed to the conformation change of human serum albumin.

Binding Sites↗