Starch Substrate Research Articles

A qualitative and quantitative histochemical investigation of the effects of pilocarpine stimulation on amylase levels in rat submaxillary and parotid glands.

A histochemical study, using the starch substrate film technique, was done to compare amylase activity in fresh-frozen cryostat sections of paired male rat parotid and submaxillary-sublingual glands, before and after pilocarpine stimulation. A quantitative procedure was followed on the same material. Amylase depletion was apparent in sections of parotid gland incubated on starch films for short periods. Quantitative estimations on adjacent sections showed an amylase depletion of about 50%. In the submaxillary-sublingual gland, amylase was demonstrable in the blood vessels in both unstimulated and stimulated material and there appeared to be a higher concentration of the enzyme in the latter. Quantitative assays on adjacent sections demonstrated a very considerably raised level of amylase activity in the stimulated submaxillary gland. It was concluded that the histochemically demonstrable amylase in the blood vessels of the submaxillary and sublingual glands was blood amylase and that the raised level following pilocarpine stimulation might be interpreted as a passage to the blood of enzymes produced by other glands under the same stimulus.

Evidence for amylase in avian salivary glands.

AbstractFour glands of the house sparrow, chicken and turkey were examined histologically and for their content of amylase. These were the external and intermediate mandibular glands, the maxillary gland and glandula anguli oris of the sparrow and the anterior and posterior mandibular, maxillary and anguli oris glands of the chicken and turkey. Amylase was determined by a starch substrate slide method and by biochemical assay. General morphology and mucopolysaccharide staining are described.All four glands of the sparrow demonstrated significant amylolytic activity by the assay. In the external mandibular and anguli oris glands this activity could be traced to mucous and seromucous cells of origin by means of the starch substrate slide procedure. None of the glands of the chicken or turkey displayed significant amylolytic activity.

Cytochemical localization and antigenicity of ?-amylase in barley aleurone tissue

Gibberellic-acid(GA3)-induced α-amylase has been localised in barley aleurone layers using cytochemical methods and light microscopy. Evidence obtained from the use of a starch substrate film method as well as immunofluorescence indicated that the first amylase to appear in the cell was associated with aleurone grains, apparently with the outer membrane, and also with the peripheral cytoplasm. In GA3-treated tissue, the amylase distribution was much more diffuse, although patchy, throughout the cytoplasm and it tended to accumulate in the endosperm side of the cell. The possibility that the aleurone grain membrane is the site of gibberellin-induced enzyme synthesis and that it proliferates to become rough endoplasmic reticulum is considered. Immunological information was obtained which supports earlier indications that induced α-amylase consists of two different proteins, each with molecular heterogeneity.

澱粉基質膜法によるティラピアおよびブルーギルの消化器官におけるアミラーゼ活性の局在

The purpose of this study is to detect the localization of amylase activity of fish which are possessed of the stomach or both the stomach and the pyloric caeca by a starch substrate film method, and to make clear the question whether other organs than the pancreas are concerned with the secretion of amylase. In Mozambique mouthbrooder amylolytic activity was found in the pancreatic exocrine tissues, at the luminal surfaces and the lumen of the intestine, and at the outer- and outside of the tracts of the stomach and the intestine. In bluegill the activity was found also in the pancreatic exocrine tissues; at the luminal surfaces and the lumen of the esophagus, the stomach, the pyloric caeca and the intestine; and at the outer- and outside of the wall of the pyloric caeca and the intestine. In both the examined species the mucosa and submucosa showed to be amylase-negative throughout the digestive tract. In sections of the pyloric caeca of bluegill and of the intestine of both species, stained with hematoxylin and eosin, pancreatic ramifications were found to be embedded in or adhere to the wall of the tracts. From the present evidences it seems that amylase production is confined to the pancreatic exocrine cells alone and the mucosal epithelial cells of the digestive tract are not associated with production or secretion of amylase. The present results are accordant with those obtained for the carp, a stomachless fish, which was earlier examined.

Determination of amylase activity in serum and urine using blue starch substrate

An investigation of the recently developed chromogenic method for the determination of amylase in serum and urine, the Phadebas Amylase Test, has been performed.The results show that it is a simple and reproducible test. The color released by the reaction is very stable and not influenced by hemoglobin, bilirubin or sugars.Addition of albumin to urine samples has made possible to determine amylase activity in protein-positive urines.

Effects of prepubertal castration on development of granular tubules and amylase activity in the male mouse submandibular gland

Male CD-1 mice were castrated between 12 and 14 days of age. Between 20 and 60 days of age the development of the submandibular glands were compared with those of normal males, normal females, and sham-operated males. Although granular tubules were apparent in the normal male at 25 days and in the normal female at 35–40 days, no distinct granular tubules were observed in castrated males until 60 days of age. An extensive development of striated ducts, however, was apparent in the castrated male submandibular gland between 35 and 60 days of age. Amylase activity, observed with a starch substrate film method, was first apparent in the normal male at 25 days and in the normal female at 35 days. In each case, the reaction was localized to the granular tubules. Amylase activity increased in direct relation to the increasing differentiation of granular tubules. In the prepubertally castrated male, weak amylase activity was detectable at 30 days in some striated ducts. This activity increased slowly up to 60 days, the age at which the granular tubules first appeared. Although the submandibular glands of castrated males and normal females appeared generally similar in morphology and amylase activity by 60 days of age, the achievement of these similarities had been attained by distinctly different patterns of development in the two groups.

On the function of granular tubules in rodent submandibular glands: Histochemical observations on Octodon degas

The submandibular gland of the Chilian rodent, Octodon degas, was studied histochemically with Alcian blue, Azure A, toluidine blue, PAS with diastase controls, and a starch substrate film method for amylase. Granular tubules were well developed in both males and females. The acini were amylase-positive. There were no apparent sexual differences in amylase activity. The Alcian blue and Azure A reactions, in addition to toluidine blue metachromasia, indicated that the acini were also acid mucosubstance-positive. The granular tubules were negative for both acid mucosubstances and amylase. The PAS reaction was intense in male acinar cells and moderate in female acinar cells. The granular tubules had a faint PAS reaction.

Localization and onset of amylase activity in mouse salivary glands determined by a substrate film method.

A starch substrate film technique was used to determine the localization and onset of amylase activity in the major salivary glands of mice. The earliest activity occurred in the parotid gland of males and females at 8 days of age. The intensity of the reaction rapidly increased so that by day 16 the entire parotid gland was amylase-positive. The submandibular gland exhibited the sexual dimorphism that has been characterized for the adult gland. Amylase activity was observed in the male at 24 days of age, shortly after the first morphologic differences between the submandibular glands of males and females became apparent. The female showed positive results at 36 days of age. Amylase activity in the submandibular glands was localized to the convoluted tubules. As the gland developed, the amylase activity increased in correlation with the increasing concentration of these tubules. The sublingual gland was always amylase-negative.

Continuous conversion of starch to glucose with immobilized glucoamylase.

AbstractPartially purified glucoamylase from Aspergillus awamori NRRL 3112 was immobilized on diethylaminoethyl cellulose in the presence of low ionic‐strength acetate buffers at pH 4.2. The active enzyme–cellulose complex was used to convert starch substrates continuously to glucose in stirred reactors. Substrate concentrations as high as 30% could be quantitatively converted to glucose at a rate of more than 25 mg/min/liter at 55°C for periods of 3 to 4 weeks in a 4‐liter reactor. Shutdowns were due to mechanical problems and not to loss of enzymes, which could be recovered with no appreciable loss of specific activity. Transfer products, such as isomaltose and panose, were present in immobilized enzyme‐produced syrups but to no greater degree than in soluble glucoamylase digests of starch.

Comparison of Two Methods for Determining Amylase Activity in Serum and Urine

Abstract Two methods for estimating amylase activity in serum and urine are compared. A method that uses a chromogenic substrate in a kit was shown to be preferable over the older amyloclastic procedure, which uses starch substrates. The precision of both methods was determined.

The coulometric determination of amylase in serum

The saccharogenic procedure for serum amylase involves the determination of reducing sugars present both before and after incubation of the serum sample with starch substrate. The standard incubation conditions are those of Somogyi. Following the incubation period, a deproteinizing step is performed and the reducing sugars present are then determined. In the present method the reducing sugars are determined by coulometric titration with generated bromine. An analysis may be performed on as little as 100 μl of serum. Turbid solutions do not interfere in the coulometric procedure. The accuracy and precision of the coulometric and a colorimetric method are comparable. Both are limited by difficulties in the steps preceding measurement rather than in the measurement step itself.

A new automated method for the determination of serum α-amylase

A simple automated method for the determination of serum α-amylase is described. It is based on a fluorescent starch substrate, possesses high sensitivity, linearity up to at least 1000 Somogyi units and permits processing of 30 samples per hour.

Salivary amylase. I. An assay method of alpha-amylase.

A micromodification of Somogyi’s starch-iodine colour method for determination of α-amylase in media from salivary gland tissue cultures, as well as homogenates of such tissues and in saliva, is described. The method was based on photometric determination of the starch-iodine colour changes during enzymic degradation of starch substrate at wavelengths 550 or 610 nm. No additional, apparently amylolytic effect, such as seen in serum, was observed by addition to the samples of 1 mg/ml of albumin and globulin, or about 1 mg/ml of proteins from homogenate of spleen. The test allows a reproducible and rapid way of calculating arbitrary units of α-amylase.

A new and rapid method for the clinical determination of α-amylase activities in human serum and urine. optimal conditions

A new type of α-amylase starch substrate rendered insoluble by cross-linking and coloured by a dye marker, was shown to be hydrolyzed by α-amylase from Hyland standard serum, Versatol-E and Enzatrol. The various conditions for enzymatic hydrolysis of such a blue starch polymer were studied. It was possible, with considerable accuracy, to determine α-amylase over more than a thousandfold range of enzyme concentration. It is felt that such a novel substrate may assume a unique importance for determination of α-amylase in various human body fluids

Stability of α‐amylase in model brewery mashes

AbstractExperiments with model mashes, of partly purified malt α‐amylase added to a grist of ethanol‐extracted pale‐ale malt confirmed that decreasing the concentration of the mash or increasing mash temperature caused an acceleration in the rate of α‐amylase destruction. the experimental mashes were devoid of proteolytic activity and contained high levels of calcium ions. the mash temperature was below that needed to inactivate the enzyme in solution, so that the instability of the enzyme was unexpected. α‐Amylase was estimated by a convenient reducing power method using a reduced starch substrate, and ‘hollow plug’ accelerated ion exchange for the removal of interfering substances.

DETERMINATION OF SERUM AMYLASE BY MEASUREMENT OF MALTOSE AND OTHER PRODUCTS FROM STARCH SUBSTRATE.

SummaryA modification of Somogyi's saccharogenic method for serum amylase is presented in which maltose and other products formed in the enzymatic hydrolysis of starch are determined photometrically by reaction with ethylamine. Various aspects of this method were studied and results compared with the Henry-Chiamori modification of Somogyi's method.

MODIFIED PROCEDURE FOR THE DETERMINATION OF DIASTATIC ACTIVITY AND α-AMYLASE ACTIVITY

Diastatic activity (Lintner value) and α-amylase activity can be determined by the same colorimetric measurements of reducing sugars formed by the action of malt extract on a starch substrate. For the determination of α-amylase activity, the β-amylase is differentially inactivated by a phenyl mercuric salt before diastasis. Measurement of reducing sugars produced is based on their reaction with 3,5-dinitro-salicylic acid. Total amylase and α-amylase activities may be recorded in the same units, or they may be converted to Lintner or SKB standard units with which they are closely correlated. There is considerable reduction in operating time and the methods are applicable in plant breeding projects or in quality control.

A starch substrate film method for the histochemical localization of amylase

A starch substrate film method for the histochemical localization of amylase

Enzymic Hydrolysis of Wheat Starch II. The effect of pH on the degradation products of wheat and corn starch substrates and their role in titanium dioxide retention

Enzymic Hydrolysis of Wheat Starch II. The effect of p_H on the degradation products of wheat and corn starch substrates and their role in titanium dioxide retention

Enzymes and their Application in Textile Processing, especially Desizing

The origin of enzymes and their general properties are outlined in brief. A variety of industrial uses is mentioned and the application of enzymes in the textile industry is discussed in some detail. Starchsplitting enzymes, amylases, are discussed in particular. Their properties are shown to be dependent on their source of origin. The mechanism of amylase action on a starch substrate is explained and distinction is made between α‐ and β‐amylase. Present‐day textile finishing has led to greater importance being given to cloth preparation and to an increasing acceptance of continuous processes. Enzymic and other desizing techniques are outlined. Mention is made of sizing materials other than starch. Removal of these substances is often materially assisted by enzyme preparations; reference is made to proteins and gums.