Methods of quantitative determination of glutathione peroxidase were reinvestigated with respect to reliability and specificity. The determination of product (GSSG) by a coupled enzymatic oxidation of NADPH, as described by PAGLIA and VALENTINE, had to be modified as follows: 1. The concentration of GSH was lowered to a maximum of 1 mM in the incubation mixture to avoid product inhibition of GS...

Within a number of classes of hydrolytic enzymes are certain enzymes whose activity is modulated by a specific inhibitor-protein that binds to the enzyme and forms an inactive complex. One unit of a specific inhibitor-protein activity is often defined as the amount necessary to inhibit one unit of its target enzyme by 50 %. No objective quantitative means is available to determine this point of...

Glycolysis is the core metabolic pathway supplying energy to cells. Whereas the vast majority of studies focus on specific aspects of the process, global analyses characterizing simultaneously all enzymes involved in the process are scarce. Here, we demonstrate that quantitative label- and standard-free proteomics allows accurate determination of titers of metabolic enzymes and enables simultan...

protein hydro-lysate was prepared from gold striped sardine (sardinella gibossa) by papain. hydrolysis conditions (time, temperature, and enzyme activity) were optimized by response surface methodology (rsm) using a factorial design and anti-oxidative activity was the dependent variable. results of the total determination coefficient, adjusted r2 and predicted r2 indicating the validity of pred...

A modification of the method of Fishman, Springer, and Brunetti (1948) for determining serum beta-glucuronidase activity is described. Normal values are presented and some of the factors which might influence the serum enzyme determination have been investigated.

An enzyme inhibiton method for the determination of serum levels of DDMP is described. This has proved to be a simple, practical, and reliable method for the clinical monitoring of patients.

Background and aim: Malassezia species are part of the resident skin flora of humans. These yeasts are associated with various superficial diseases, including seborrheic dermatitis, atopic dermatitis, dandruff, and psoriasis. Various DNA-based molecular methods have been recently described to differentiate species of Malassezia. In this survey, a simple, reliable, and cost effective PCR-b...

An enzyme electrode was developed using the enzyme sulfite oxidase (EC1.8.3.1) immobilized onto pig intestine. Hydrogen peroxide produced was monitored amperometrically. All experimental parameters such as pH, temperature, buffer constituent concentration, were thoroughly investigated and optimized when appropriate. The response to sulfite concentration was linear in the range 5.2´...

Serum cortisol level was measured by an enzyme immunoassay (EIA) using the enzyme penicillinase as a label without prior extraction and purification. Polyclonal antibodies were raised against cortisol-3-ortho-carboxymethyl-oxime (cortisol-3-0-CMO) conjugated to bovine serum albumin (BSA). This antibody showed a very low cross-reactivity with structurally related steroids (3.7% for corticos...

Fats and oils as major dietary components are involved in the development of chronic diseases. In this paper the physiological relevance and some methodological aspects related to the determination of two enzymes enrolled in metabolism of fat – pancreatic lipase and arylesterase – are discussed. Pancreatic lipase has been extensively used to study the triacylglycerol fatty acid composition and ...