A series of studies in this laboratory have focused on how an indigenous microbiota influences the activities of alkaline phosphatase, phosphodiesterase I, and thymidine kinase in the enterocytes of the upper small intestine of mice. To draw conclusions about the role of the microflora in determining levels of enzymatic activity, we found it necessary to develop a procedure by which cell suspen...

We describe an enzymatic method for measuring phosphatidylglycerol (PG) at concentrations as low as 0.2 mumol/L in amniotic fluid. Amniotic fluid (1.5 mL) is centrifuged at 10,000g for 20 min to obtain a lamellar body pellet, which is reconstituted with 0.5 mL of buffer. The PG is measured by a two-step enzymatic scheme. Recovery studies demonstrated that the pellet contains > 97% of the PG pre...

Delgado-Andrade C., Rufián-Henares J. A., Morales F. J. (2008): Optimised procedure to analyse Maillard reaction-associated fluorescence in cereal-based products. Czech J. Food Sci., 26: 339–346. Fluorescent Maillard compounds measurement provides more specific information on the extent of the Maillard reaction than other unspecific tools to monitor the reaction, and is suitable, as the first a...

The reversal of the proteolytic cleavage of the peptide bond by proteases leads to the enzymatic peptide synthesis. In contrast to the chemical synthesis enzymes form the peptide bond without the danger of racemisation. The coupling can be conducted in aqueous buffer, no hazardous chemicals are necessary. Quite often side chain protection of the amino acids can be omitted, thus simplifying the ...

The low incidence of group B streptococcal (GBS) invasive neonatal disease in Mexico has been attributed to the low prevalence of serotype III strains, a major serotype in developed countries. In addition, nontypeable strains account for 12% of the isolates in Mexico and < 1% of the isolates in the United States. In this study, 57 GBS isolates (28 nontypeable by the Lancefield procedure) from c...

A simple procedure for determining the galacturonic acid and methanol contents of soluble and insoluble pectins, relying on enzymatic pectin hydrolysis and colorimetric quantification, is described. Pectin samples are incubated with a commercial pectinase preparation, Viscozyme, then the galacturonic acid content of the hydrolyzed pectin is quantified colorimetrically using a modification of th...

We describe a sensitive method for quantifying the extent of cholesterol ester cleavage during enzymatic assay of total cholesterol in serum. Lipids are extracted from the assay mixture with chloroform/methanol (1/1 by vol), concentrated, then quantified by "high-performance" thin-layer chromatography. Although with conventional enzymatic reagents for determination of serum total cholesterol th...

nineteen bread wheat genotypes were selected to examine the effect of glycine betaine (gb, 100 mm) on various photosynthetic gas exchange parameters under drought stress and to study the relationship of these parameters with non-enzymatic antioxidants. drought stress caused a significant decline in net co2 assimilation rate (pn), stomatal conductance (gs), intercellular co2 concentration (ci) a...