Thrombin is the central enzyme of haemostasis. Information on the production and inhibition of thrombin in plasma is important for evaluating the state of the coagulation system. Measurement of thrombin generation in plasma using small oligopeptide chromogenic substrates gives rise to a signal that not only reflects the enzymatic activity of free thrombin, but also contains a contribution of th...

An automated Cobas Fara method was developed determining the activity of recombinant M. thermophila laccase (rMtL). The chromogenic substrate used was syringaldazine. Under aerobic conditions, rMtL catalyses the oxidation of syringaldazine forming tetrametoxy-azo bis methylene quinone. The developed violet colour was measured kinetically at 530 nm as an expression of the enzyme activity, rMtL i...

The concentration of heparin in plasma was measured using a chromogenic substrate. It appeared that the measurement of heparin concentration in plasma was important in therapeutic control and evaluation of heparin. There was a correlation between the activated partial thromboplastin time (APTT) and heparin concentration in plasma, but since the gradients of regression line differed in each of t...

One of the latest techniques that used in recent decade to rapid detection of pathogenic agent in water and food is chromogenic media. These media are very specific and their component act as substrate for specific enzyme and depending on enzyme exhibit special color. This study is an introduction to chromogenic media as a powerful tool to rapid identification of bacterial and fungal agent in w...

The purpose of this study was to devise an algorithm utilizing chromogenic media for the detection and presumptive identification of Candida species in a clinical microbiology laboratory. In order to select one chromogenic medium, a limited evaluation of 3 commercially available yeast chromogenic media: BBL CHROMagar Candida, BioRad CandiSelect 4, and Oxoid OCCA, was conducted with 12 C. albica...

Parisi, Joseph T. (Duquesne University, Pittsburgh, Pa.). Significance of chromogenic variants in studies of virulence factors of Staphylococcus aureus. J. Bacteriol. 92:589-591. 1966.-Large numbers of chromogenic variants were isolated from cultures of a parent strain of Staphylococcus aureus growing in Brain Heart Infusion (Difco). The parent strain and four selected chromogenic variants were...

A chromogenic Limulus amoebocyte lysate (LAL) endpoint assay was found to be an accurate and rapid means of gauging levels of beef carcass microbial contamination within 10 min. The assay demonstrated a high correlation with the total mesophilic bacterial and coliform surface populations from inoculated beef carcass surface tissues. This assay was tested on a set of actual beef carcass surface ...

A new cephalosporin with a highly reactive beta-lactam ring was found to give an immediate color change in the presence of beta-lactamases from many bacteria, including staphylococci, Bacillus species, Enterobacteriaceae, and Pseudomonas. The reaction is confined to organisms producing beta-lactamases, but it is sufficiently sensitive to indicate the presence of this enzyme is small amounts in ...

Methods employing chromogenic substrates for the photometric determination of prothrombin time have several advantages over conventional coagulometric methods. We evaluated the analytical qualities of two recently introduced reagents for the photometric determination of prothrombin time. The assays were performed on a centrifugal analyser. Both reagents showed good precision, even with sample v...

We compared the modes of action of human pancreatic, human salivary, and porcine pancreatic amylases on Cibachron Blue F3GA-amylose. Both human enzymes showed similar catalytic activity with almost equal Vmax but dissimilar apparent Km's. The ratios of soluble dyed oligosaccharides to reducing substances were identical. Porcine pancreatic amylase exhibited less than half the Vmax of the human e...