Showing papers on "Amylase published in 1968"

Enzyme method for determination of α-linked glucose polymers in biological materials

Abstract: A review of methods available for the determination of starch suggested, for reasons given, that none was satisfactory for the determination of α-linked glucose polymers in biological materials. Therefore, a method was devised in which the specific hydrolysis of starch completely to glucose is achieved by means of an amyloglucosidase. Glucose is estimated using glucose oxidase. Contents of α-linked glucose polymers in a number of biological samples were determined, and compared with those obtained using 0.36 N-H2SO4 to effect hydrolysis.

Chemically coupled enzymes

Abstract: 1283958 insolubilized enzymes CORNING GLASS WORKS 3 Sept 1969 [5 Sept 1968] 43514/69 Heading C3H An insolubilized enzyme comprises an enzyme coupled covalently to an inorganic carrier having available hydroxyl or oxide groups, said enzyme being coupled to the carrier by means of an intermediate silane coupling agent wherein the silicon portion of the molecule is attached to the carrier and the organic portion of the molecule is attached to the enzyme. The enzyme may be papain, ficin, pepsin, trypsin, chymotrypsin, bromelin, keratinase, Bacillus subtilis alkaline protease, cellulase, amylase, maltase, pectinase, chitinase, lipase, cholinesterase, lecithinase, alkaline or acid phosphatase, ribonuclease, desoxyribonuclease, arginase, asparaginase, glutaminase, urease, glucose oxidase, catalase, peroxidase, lipoxidase, cytochrome reductase, glutamic-pyruvic transaminase, glutamic-oxalacetic transaminase, transmethylase or phosphopyruvic transphosphorylase. The carrier may be porous glass, colloidal silica, wollastonite, dried silica gel, bentonite, alumina, hydroxy-apatite, or nickel oxide.

Hyperamylasemia from the Binding of Serum Amylase by an 11S IgA Globulin

Abstract: A patient with persistent hyperamylasemia and a low renal clearance of amylase was found to have an abnormally large serum amylase (11S). This large amylase, as shown by preparative ultracentrifugation and gel filtration, comprised 95 per cent of amylase in serum and 5 per cent of that in fasting small-bowel contents. Remaining amylases in serum, intestinal fluid, urine and saliva were of normal size (4–5S). The abnormal amylase was specifically precipitated with anti-IgA antiserum. Mercaptoethanol reduced the sedimentation coefficient of the large amylase to 7–8S; treatment at pH 3.4 reduced its sedimentation coefficient to normal (4–5S). Gel filtration at pH 3.4 resulted in the separation of an amylase that was normal in size and enzyme kinetics. The globulins isolated by acid dissociation bound amylase present in normal serum and increased its size to 11S. These observations are consistent with the hypothesis that hyperamylasemia and large-sized amylase result from the binding of normal amylas...

Correlated changes of some enzyme activities and cofactor and substrate contents of pea cotyledon tissue during germination

Abstract: 1. The activities of six enzymes (hexokinase, phosphoglucose isomerase, phosphofructokinase, aldolase, glucose 6-phosphate dehydrogenase and amylase) in extracts of pea cotyledons were determined. The activities during the first 10 days after germination showed individual and characteristic changes that indicate a specific control of both synthesis and destruction of enzymes. 2. Tissue contents of glucose, inorganic phosphate, glucose 6-phosphate, fructose 6-phosphate, ATP, ADP, AMP, NAD and NADP were also determined, and a correlation is reported between the substrate concentrations at day 1 and the subsequent enzymic activity. 3. The initial NAD+/NADH ratio value of 1 changed to about 3 by day 4; the NADP content was lower and changes in the oxidation state were less striking. The ratio of ATP to ADP and AMP remained virtually constant.

Antibacterial Activity of the Purified Peroxidase from Human Parotid Saliva

Abstract: The peroxidase of human parotid saliva has been purified by concentration, gel filtration on Sephadex G-200, and ion exchange chromatography on Amberlite CG-50. The purified product was devoid of amylase activity, lysozyme activity, and immunoglobulin A (IgA). However, it had an inhibitory effect on the growth of Lactobacillus acidophilus in complete growth medium and on lysine accumulation by L. acidophilus in a buffer-glucose medium, when combined with thiocyanate ions. The concentrations of peroxidase and thiocyanate ions employed were within the range found in saliva. The fractions which contained IgA did not have an anti-bacterial effect on L. acidophilus under the conditions employed. Parotid saliva also contained low molecular weight inhibitors of peroxidase activity. These studies support the involvement of the salivary peroxidase in an antibacterial system in saliva.

Effect of Auxin on Cell Wall Degrading Enzymes

Abstract: The effect of auxin on the activities of amylase, cellulase, β-1, 3- and/or β-l, 6-glucanase and hemieellulase were observed using etiolated barley coleoptile and pea epicotyl internode segments. The activities of β-1, 3- and/or β-l, 6-glueanase and hemicellulase of barley were increased by indole-3-acetic acid in a 3 hours' treatment. Amylase activity was not influenced by the auxin. Cellulase activity was not detected under the experimental conditions. 2, 4-Dichlorophenoxyacetic acid increased hemicellulase activity, but not cellulase and amylase activities, in pea epicotyl segments in 3 hours. Fungal β-1, 3-glucanase exogenously applied induced the elongation of barley coleoptile segments. The elongation induced by the enzyme was as high as that induced by indole-3-acetic acid at least for the first 1 to 3 hours.

Inhibition of wheat α‐amylase by bran phytic acid

Abstract: A proportion of the wheat samples tested for α-amylase activity by the Hagberg penetrometer method during the 1961 New Zealand harvest gave higher results on flours than on wheatmeals milled from the same wheats. This effect is due to the lower level of calcium available as enzyme cofactor in the meals, caused by combination with phytic acid. Because of this effect and because the internal distribution of α-amylase in wheat grains is variable, testing for sprout damage in milling wheat is best carried out on flours rather than wheatmeals.

Ethylene Enhanced Release of α-Amylase From Barley Aleurone Cells

Abstract: Ethylen,e iniduces var,ious physiological effe,cts in higher plants (3) and recenit evidence suggests thait at least some oif these events are mediated by influtencting protein synthesiis (1, 5). T'hi,s paper describes the ef fects of ethylene on the synthesis anid release of a-amylase from barley alleurone layers. Varne,r and co-workers (10, 11), have shown that a-amyla'se is produced de novo in aleuro,ne Ilayers following treatment with gibberellic acid (GA,) and that amyliaise is secreted from the aleuirone l,ayers by a specific secretory mecihanism. The met'hods usecl for preiparation of ba,rley aleurone layers and determination of a-amylase are simiilar to those descrilbed by Chrispeels and Varner (4) anid Jones and Varner (6). The amount of a-amylase obtained from the incuibaiting atleurone layers was expressed in terms of uin,its of a-amylase AL OD X Tv using the formula whe-re T, total t X v voilu-me of incubate: t time of inlcuibation of starch with saimple; v samp.le voluime (6). Incutbation of aleurone layers was accomplished in vaccine-ca(pped flasks ainld eothylene wias introduced through the caps using gas-tight syringes. The secretion of a-amylase inlto the mediulll surrooun(ling aleurone cellls folllows a char-acter,istic patterni. During the first 5 to 8 hours fo1llowing GA, applicationino a-amv'lase is secreted, this is referred to as the lag pericdtl. Following this lag p)eriod, a-amvlase oseoretion is lineear with time for approximately 12 to 18 hours a.fter which secretion declines. Consequently, in most experiments the flasks were sampled after 18 hlours oif incubation. Simultaneou-s addition of ethylene and GA3 t-o alenrone layers resullited in an increase in the am,ount

Effects of Soil Salinity and Growth Regulators on Germination and Seedling Metabolism of Wheat

Abstract: Germination studies were carried out with the wheat varieties NP823, Karchia, Sonora 63, Sonora 64, Mayo 64 and Lerma Rojo in artificially salinized soil maintained at ECe 2, 8, 12 and 16 mmhos/cm at 25°C. Early seedling growth and metabolism of variety NP 823 was studied in salt solutions alone and with addition of the growth regulators GA3 and Cycocel (2-chloroethyl trimethylammonium chloride). Soil salinity both depressed and delayed the germination. Among the varieties tested NP 823 and Karchia were relatively less susceptible to salt injury while Lerma Rojo exhibited a maximum susceptibility. Salt supply also brought about a reduction in the early seedling growth, the release of reducing sugar and the amylase activity. The adverse effect on amylase activity was not mediated through the synthesis of enzyme protein but by an inhibition of the enzyme activity. Exogenous supply of GA3 counteracted the adverse effect of salt on amylase activity and the release of reducing sugar but not on the early seedling growth.

Kaffircorn malting and brewing studies XIX.—gibberellic acid and amylase formation in kaffircorn

Abstract: Gibberellic acid had little effect on amylase development in normal kaffircorn. Only immature seeds and very large grains produced more amylase when treated with gibberellic acid, but this effect was much smaller than that found with barley. Addition of gibberellic acid to isolated sorghum endosperms failed to stimulate significant amylase formation. Isolated endosperms also failed to produce amylase after normal contact with their embryos for up to 48 hours of germination. Amylase formation in sorghum appears, therefore, to be preponderantly a function of the embryo.

Serum Amylases, Isoenzymes, and Pancreatitis I. Effect of Substrate Variation

Abstract: Four plant starches were used to study human amylase activity in normal serum and urine, "pancreatitis" serum, duodenal fluid (secretin stimulated), saliva, and pancreatic extract. The starches were derived from waxy maize, high amylose corn, potato, and corn (pearl), and were lintnerized. It was shown that the rate of digestion of starch by each of the fluids tested depends on the plant starch selected as substrate. Digestion of waxy maize was most rapid. The advantages of using waxy maize as a substrate are indicated as a means of markedly enhancing the sensitivity of serum amylase determination. It was also found that normal serum, urine, and saliva digested potato starch at a greater rate than corn starch with few exceptions, while pancreatitis serum, secretin-stimulated duodenal fluid, and pancreatic extract digested corn starch at a greater rate than potato. These findings suggest that organ-specific amylases exist, and that plant starches might be used to distinguish them.

Distribution of Soluble Proteins and Enzymes During Early Development of Pisum Sativum

Abstract: Changes in soluble protein and in peroxidase, esterase, and amylase enzymes during development of the pea plant (P. sativum) have been investigated using a horizontal method of acrylamide gel electrophoresis. Both qualitative and quantitative variation between organs at different stages of physiological development are recorded.

Exocrine function of the chick pancreas as affected by dietary soybean meal and carbohydrate.

Abstract: Chicks develop an enlarged pancreas when fed unheated soybean meal. Autoclaving the meal destroys or inactivates the heat-labile component(s) which cause this effect on the pancreas 5. Recent histological studies in our laboratory 24 have confirmed that this enlargment is due to hyperplasia of the pancreatic acinar cells, but the cause of this hyperplasia is not known 2. Homogenates of the enlarged pancreas have lower amounts of amylase, but higher levels of trypsin and chymotrypsin 20. Grossman et al. 9. and more recently Desnuelle et al. 6, suggested that differences in levels of pancreatic enzymes could be due to different rates of synthesis in response to dietary composition and/or an altered rate of secretion of enzymes from the pancreas. Most of the published results on pancreatic changes were obtained with pancreatic homogenates, a technique that precludes distinction between the suggested alternatives.The purpose of the present study was to determine the effect of changing the nature, or source, o...

Fine Mapping Analysis Of The Amylase Gene In Bacillus Subtilis By Transformation

Abstract: To make genetic analysis of the amylase gene (amy) of Bacillus subtilis, selective markers linked to amy were looked for. As the result, phe96 (phenylalanine) and aro116 (aromatic amino acids) were found to be linked to amy. The two mutations were closely linked each other.By use of the linked markers, fine mapping of amylase negative mutations was carried out by transformation. Sixteen amylase negative mutations so far isolated were mapped in a single locus.