Six different methods for alpha-amylase determination were compared by assaying human serum samples covering a wide range of alpha-amylase values. All the methods studied use as substrate a maltooligosaccharide with a chromophore group at the reducing end; some are chemically blocked at the nonreducing end. Intermethod comparison by regression and correspondence analyses showed significant diff...

α-Amylase from Trichoderma harzianum was covalently immobilized on activated wool by cyanuric chloride. Immobilized α-amylase exhibited 75% of its initial activity after 10 runs. The soluble and immobilized α-amylases exhibited maximum activity at pH values 6.0 and 6.5, respectively. The immobilized enzyme was more thermally stable than the soluble one. Various substrates were hydrolyzed by imm...

Addition of albumin, gamma-globulin, alpha-casein or submaxillary mucin to the assay system for chromogenic measurement of human or rat amylase with blue starch increased the amylase activity, albumin having the most effect. These proteins seemed to increase the activity by protecting amylase from inactivation. Amylase activity was higher in urine samples showing proteinuria than in urine sampl...

When embryonated and de-embryonated cotyledons of cowpea (Vigna unguiculata L.) were kept for germination, only embryonated cotyledons (EC) developed into seedlings. alpha-Amylase activity appeared late in de-embryonated cotyledons (DEC), but increased and matched with that of EC on 4th day, and thereafter started declining. A higher content of reducing sugars may be one of the factors in down ...

Biochemical analysis and immunohistochemical techniques support the theory that hyperamylasaemia in lung cancer is due to amylase production in carcinoma cells. The vast majority of amylase-producing carcinomas are adenocarcinomas with amylase isoenzyme similar to the salivary type. This prospective study assesses alpha-amylase expression in resectable lung cancer. Seventy four patients with re...

The Nelson photoelectric method for the determination of glucose in biological fluids (1) has proved to be the method of choice in this laboratory and in many others, owing to its reproducibility, stability of color, and excellent agreement with the Beer-Lambert law. Nelson, however, states that the method is unsuitable for the determination of diastatic activity. Since it is convenient and eco...

A saccharogenic method is described for estimating amylase activity in human urine. Results accord with those reported elsewhere except that in this study the peak in the beta zone is a new finding. Comparison between normal and pathological urines suggests that the amylase activity of the beta peak is not of pancreatic origin.

The alpha-amylases in the salivary glands of Lygus hesperus Knight and L. lineolaris (Palisot de Beauvois) were isolated and purified by ion exchange chromatography, and by isoelectric focusing, respectively. The alpha-amylase from L. hesperus had an isoelectric point (pI) of 6.25, and a pH optimum of 6.5. The specific activity of alpha-amylases in the salivary glands of L. hesperus was 1.2 U/m...

The Nelson photoelectric method for the determination of glucose in biological fluids (1) has proved to be the method of choice in this laboratory and in many others, owing to its reproducibility, stability of color, and excellent agreement with the Beer-Lambert law. Nelson, however, states that the method is unsuitable for the determination of diastatic activity. Since it is convenient and eco...

A glucosyl and a glucosyl-glucan transferase activity from spinach (Spinacia oleracea L. var. Matador) leaves have been partially purified and characterized. The latter activity (fraction 1 after diethylaminoethylcellulose chromatography) is responsible for the transfer of glucosyl as well as of maltosyl, maltotriosyl, and higher homologous residues to glucose giving rise to maltose and the cor...