Soluble Starch Solution Research Articles

Rheological Properties of Coating Colors Containing Biobased Latex

This paper focuses on the understanding of basic properties of water-swollen crosslinked starch nanoparticles as a function of crosslink density. The extent of their water swelling is decreased with increasing particle crosslink density and solid concentration and vice versa. This study elucidates the unique rheological properties of starch nanoparticle dispersions and paper coating formulations in comparison with water-soluble cooked starch and synthetic latex counterparts. These rheological studies extend over many decades of shear rates, using several different rheometers. Low shear viscosities were obtained using a Cannon-Fenske viscometer and a TA AR-2000 stress rheometer with double concentric cylinder geometry. Intermediate shear rate rheology was evaluated with a Hercules rheometer. High shear rates were studied with ACAV A2 ultra-high shear capillary and slit rheometers. Unlike conventional cooked and soluble starch solutions, starch nanoparticle latex dispersions are colloids that consist of internally crosslinked particles. With increasing intra-particle crosslink density these biobased colloids have been found to behave much like petroleum based synthetic latex colloids. However, at ultra-high shear their rheological properties are relatively more shear thinning compared to hard particles, including synthetic latex and pigment particles, which exhibit shear-thickening and dilatancy. The implications of the rheological data on high-speed coater runnability are discussed.

Combined Effects of a Dietary Fiber Mixture and Wheat Albumin in a Rat Model of Type 2 Diabetes Mellitus.

As bioactive ingredients of functional foods, dietary fiber and wheat albumin (WA) are known to suppress hyperglycemia in patients with type 2 diabetes mellitus. The combined effects of these bioactive ingredients were examined using an animal model of type 2 diabetes mellitus. First, oral starch tolerance tests (OSTTs) with the simultaneous intake of a dietary fiber mixture (DF) and WA were performed as an acute study. Male Goto-Kakizaki rats received a soluble starch solution [700 mg/kg body weight (bw)] containing DF and/or WA (each 300 mg/kg bw). In these OSTTs, the combined intake of DF and WA suppressed hyperglycemia much more effectively than each separate intake. Second, in a chronic intake study, diets containing DF and/or WA were administered to male Zucker diabetic fatty rats over 84 d. The combined effects of DF and WA were not observed in glycosylated hemoglobin concentration levels or fasting blood glucose levels, but appeared as an improvement in liver lipid contents. Variations in the liver lipid contents were similarly reflected in those of the plasma lipid concentrations. In conclusion, this study found that the simultaneous intake of bioactive DF and WA improved the postprandial hyperglycemia and the chronic lipid metabolism disorders in rat models of type 2 diabetes mellitus.

Synthesis of silver nanoparticles in DMSO solutions of starch: a comparative investigation of native and soluble starches

time. The starches acted as reducing and stabilizing agents simultaneously. The kinetics of the process and its activation energy were determined by using UV-vis spectroscopy. The DMSO solution of soluble starch was characterized by better reductive activity than the native starch solution. The morphology and dispersion characteristics of AgNPs sols were evaluated from transmission electron microscopy (TEM). Sols, including spherical particles with mean diameter (Dm) 42.8 nm and metal rod-like particles, were obtained by using the native starch solution. Morphologically uniform sols of spherical AgNPs with Dm=37.2 nm were formed in the soluble starch solution. On the basis of zeta potential measurements, it was shown that the stability of a AgNPs dispersion in the soluble starch solution was higher in comparison to the native starch solution.

The regulatory effects of resistant starch on glycaemic response in obese dogs

The purpose of this study was to examine the inhibitory effects of resistant starch on postprandial glycaemic response in obese dogs. The changes in blood glucose concentrations and glycaemic index (GI) were chronologically determined after the administration of resistant and normal starches by nasal feeding. Resistant starch contained indigestible dextrin (IDD) and β-cyclic dextrin (β-CD). Soluble starch (SS) served as a control starch. Glucose concentrations reached their maximum 15 min after the administration of SS solutions, and decreased gradually during the experimental period. In contrast, after the administration of IDD solutions, increased glucose concentrations rapidly decreased to the initial values. After the administration of β-CD solutions, glucose concentrations remained unchanged during this study. GI levels remained constant in the following order: β-CD < IDD < SS. GI levels of dogs receiving IDD and β-CD solutions were significantly lower as compared with those animals receiving SS solutions. In this study, nasal tube feeding was an effective method for evaluating glycaemic responses to various starches accurately. The present data revealed that resistant starches were useful materials in controlling nutritionally glucose concentrations in obese dogs. These results raise the possibility that resistant starches are valuable for dietetic treatment of diabetes and obesity in dogs.

Study on Characteristics in the Removal Process of Ammonia Nitrogen and Nitrate Nitrogen by an Isolated Heterotrophic Nitrification-Aerobic Denitrification Strain Rhodococcus Sp.

Removal of ammonia nitrogen and nitrate nitrogen by an heterotrophic nitrification-aerobic denitrification strain is an economical and effective method. In this article, a kind of heterotrophic nitrification-aerobic denitrification strain which has aerobic denitrification and heterotrophic nitrification ability was selected, and then was identified as rhodococcus sp. by 16S rRNA sequencing analysis and morphological observation. After that, carbon source utilization and nitrification- denitrification activity of this strain in different C/N, initial nitrogen concentration were studied. In addition, the assimilation and denitrification activities of ammonia and nitrate were also researched under the condition of nitrate and ammonia coexisted in the solution. The results show that the strain can grow in sodium acetate, glucose, sodium succinate and sodium citrate solutions, and it can not survive in sodium oxalate, sucrose and soluble starch solutions. Initial concentration and C/N were important for nitrogen removal rate. This strain can completely remove nitrate/ammonia when nitrate/ammonia concentration was lower than 15 mg l-1/80 mg l-1. the C/N of 10 and of 12 were the optimum C/N ratio in the nitrate and ammonia removal process respectively. pH value rose up sharply in the denitrification process and it increased relatively slowly in the nitrification process, which shows that pH is one of the most important factor inhibiting the denitrification removal process. Nitrite concentration was much higher in denitrification process than in nitrification process. In addition, this strain gave priority to utilizing ammonia as nitrogen source when ammonia and nitrate coexisted in the solution.

Accurate evaluation and verification of varietal ranking for flooding tolerance at the seedling stage in barley (&lt;i&gt;Hordeum vulgare&lt;/i&gt; L.)

Soil flooding or waterlogging is a major abiotic stress in upland crops. In barley, there have been several reported studies of selection for flooding-tolerant genotypes, but it is difficult to obtain varietal rankings that are consistent among researchers. Our objectives were to establish experimental conditions that could be applied by other research groups and to verify the varietal ranking conducted in an earlier study. We conducted greenhouse experiments on 14 barley varieties. At the 2.5-leaf stage, they were flooded with 0% or 0.1% soluble starch solution (mimicking reducing conditions). At 13 to 15 days after the start of treatment, the degree of leaf injury and the shoot dry weight ratio (treatment:control) were recorded. Reliable and highly repeatable results were obtained for the criterion of leaf injury under reducing conditions, whereas shoot dry weight ratio was unstable. The varieties OUJ820 and OUA301 were highly tolerant, whereas OUA002 and OUJ247 were sensitive; these results matched those of the earlier study. The experimental conditions that we developed here may be useful for selection testing and genetic analysis of flooding tolerance in other laboratories.

Green synthesis and characteristic of core-shell structure silver/starch nanoparticles

An eco-friendly method was put forward to synthesize Ag nanoparticles (Ag NPs) by using biodegradable starch as a stabilizing agent. The silver ion from AgNO 3 was reduced by glucose in soluble starch solution. Morphological observation and characterization of Ag NPs were performed by using high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD) and UV–vis absorption spectroscopy. HRTEM showed that Ag NPs were covered by starch layer to form spherical core-shell Ag/starch NPs with diameter ranging from 5 to 20 nm. XRD pattern confirmed the presence of Ag NPs with face-centered cubic (fcc) structure. All these results indicated that starch played an important role in stabilizing Ag NPs.

Production of cyclodextrin by poly-lysine fused Bacillusmacerans cyclodextrin glycosyltransferase immobilized on cation exchanger

Bacillus macerans cyclodextrin glycosyltransferase (CGTase) fused with 10 lysine residues at its C-terminus (CGTK10ase) was immobilized onto a cation exchanger by ionic interaction and used to produce α-cyclodextrin (CD) from soluble starch. Poly-lysine fused immobilization increased the V m of the immobilized CGTase by 40% without a change in K m. The activation energies of thermal deactivation ( E a) were 41.4, 28.1, and 25.9 kcal mol −1, respectively, for soluble wild-type (WT) CGTase, soluble CGTK10ase, and immobilized CGTK10ase, suggesting destabilization of CGTase by poly-lysine fusion and immobilization onto a cation exchanger. Maximum α-CD productivity of 539.4 g l −1 h −1 was obtained with 2% soluble starch solution which was constantly fed at a flow rate of 4.0 ml min −1 ( D = 240 h −1) in a continuous operation mode of a packed-bed reactor. The operational half-life of the packed-bed enzyme reactor was estimated 12 days at 25 °C and pH 6.0.

Effect of substrate presoaking treatment of support materials on the activity of immobilized glucoamylase

The activity of immobilized glucoamylase was remarkably increased by presoaking treatment of the supports in soluble starch solution. Pig bone (PB) particles-100 showed the largest substrate presoaking effect among some representative support materials, increasing the activity of immobilized glucoamylase by 10 times. The improvement in the activity was due to the increase in the specific activity of immobilized proteins. In order to get sufficient substrate presoaking effect, a rapid crosslinking treatment of the enzyme and the substrate-presoaked support was required. The glucoamylase immobilized on PB sheet was very stable and gave a high starch hydrolysis of DE95 (dextrose equivalent) for about 1 month in continuous process.

Disposable Capillary Fill Device for the Colorimetric Determination of p-Aminophenol as Indophenol Blue

Abstract The construction of a disposable capillary fill device, by which p-aminophenol in the range 10-40 μg ml−1 can be determined by a visual comparison method, is described. The inside face of one glass plate of which the device is constructed is coated with a reagent layer produced by brushing on to it a soluble starch solution containing sodium hydroxide, potassium dihydrogen phosphate, and phenol, which is subsequently dried. When a sample solution containing p-aminophenol is taken up into the device by capillary action, the reagent layer dissolves and indophenol is formed by oxidation of the p-aminophenol with phenol in the alkaline conditions by dissolved oxygen in the sample solution. The p-aminophenol concentration of sample solutions is determined by visual inspection compared with the known colour produced by a series of standards.

High rates of exogenous carbohydrate oxidation from starch ingested during prolonged exercise

This study compared the gastric emptying and oxidation of two 15% carbohydrate (CHO) solutions: a 22-chain-length glucose polymer (GP) and soluble starch (SS). Six endurance-trained subjects ingested 1,200 ml of either GP or SS while cycling for 90 min at 70% of maximal oxygen consumption (VO2max). Whereas the calculated total CHO oxidation (GP 266.8 +/- 41.9 g; SS 263.6 +/- 28.9 g) and the volume emptied from the stomach (GP 813 +/- 130 ml; SS 919 +/- 116 ml) were similar, the appearance of the 14C label in plasma occurred more rapidly from ingested SS than from GP (P less than 0.001). This resulted in a significantly greater rate of SS oxidation than that from GP (SS 105.9 +/- 21.9 g, GP 49.6 +/- 10.2 g; P less than 0.001). Exogenous CHO oxidation from GP accounted for 19% of total CHO oxidation, whereas the corresponding value for SS was 40%. This study suggests that the oxidation of SS and GP solutions ingested during exercise at 70% VO2max is not limited by gastric emptying. Rather, it appears to be either the rate of digestion or absorption of these solutions that determines their utilization.

Raw starch adsorption-desorption purification of a thermostable β-amylase from Clostridium thermosulfurogenes

The β-amylase from Clostridium thermosulfurogenes was readily adsorbed onto raw starch. The adsorbed β-amylase was eluted from raw starch by using boiled soluble starch solution as an clutant. The soluble starch treated β-amylase could not adsorb onto raw starch which indicates that the soluble and insoluble substrate binding sites of the β-amylase may be the same. The β-amylase was purified to homogeneity by raw starch adsorption-desorption techniques and octyl-Sepharose chromatography. It had a specific activity of 4188 units/mg protein. The insoluble substrate adsorption-desorption technique may be used for the purification of other enzymes.

Immobilized cyclomaltodextrin glucanotransferase of an alkalophilic Bacillus sp. No. 38‐2

Cyclomaltodextrin glucanotransferase [1,4-alpha-D-glucan-4-alpha-D-(1,4-alpha-D-glucano)-transferase (cyclizing), E.C.-2.4.1.19] of an alkalophilic Bacillus sp. No. 38-2 (ATCC 21783), which contains three types of enzymes (acid, neutral, and alkaline enzymes), was immobilized on synthetic adsorption resin. No distinguishing changes in pH or thermal stabilities of enzyme were observed due to the immobilization. Since acid-enzyme activity had disappeared, the optimum pH of immobilized enzyme was 9.0. Optimum temperature for the enzyme activity changed from 50 to 55 degrees C. The enzyme converted starch to cyclodextrins without significant loss of activity under the conditions of continuous reaction for about two weeks by using the column system (60 degrees C at pH 8.0). About 63% of soluble starch solution [4% (w/v)] was changed to cyclodextrins, as tested so far.

Immobilization of alpha-amylase, glucoamylase and glucose isomerase on CNBr activated Sepharose-6MB

Two enzymes (Glucoamylase from Rhizopus Sp. and Glucose isomerase from Streptomyces fradiae) or three enzymes (the above two and α-amylase from Bacillus subtilis) were coupled to CNBr activated Sepharose-6MB. Some of the parameters such as the pH and temperature activity relationships of the immobilized enzyme systems are described. A 5% soluble starch solution was converted by the enzyme system into a mixture of glucose and fructose within 6 hr at 60° C.

Quantitative gel-electrophoretic determination of serum amylase isoenzyme distributions.

I report a direct, sensitive, quantitative method for determining serum amylase isoenzyme activity with commercially available reagents. Day-to-day reproducibility (CV) was 3--4% for the isoenzymes in normal serum; within-run precision was 8, 3, and 2% for low, normal and high isoenzyme activities. Amylase isoenzymes, separated into the pancreatic and salivary types by electrophoresis in polyacrylamide gel, are then quantified by directly incubating the gels in soluble-starch solution, staining with iodine, and densitometry. The proportion of pancreatic isoenzyme (47 normal sera) was 43 +/- 8% (mean +/- SD). Isoenzyme activities as low as 2% of normal can be measured accurately in 10 micro L of serum. The reproducibility, precision, and sensitivity indicate that the method is applicable to differential diagnosis of hyperamylasemia or hypoamylasemia, and is suited for monitoring the subtle changes in serum amylase isoenzyme distribution that may accompany disease progression or therapy.

でんぷんのリンと生でんぷんの酵素分解

Raw potato and wheat starch granules were digested by B, subtilis alpha-amylase(crystalline) at 45°C with constant shaking and the molecular properties of digested granules were examined. The contents of phosphates, total (Pt) and located at C-6 of a glucose residue, of digested potato starch decreased significantly and its blue value and unit chain-length increased slightly with the progress of the digestion. While, the contents of Pt and choline compounds of digested wheat starch increased appreciably (these remained nearly quantitatively in the digested residue) and its blue value and unit chain length increased slightly. These results suggest that the vicinities of the phosphates-bound sites of potato amylopectin are preferentially eroded by the enzyme and the amylose-phospholipids complexes of wheat starch are immune from the action of the enzyme. The immunity of amylose-phospholipids complex from the action of the enzyme was supported by the facts that the hydrolysis of a soluble starch solution by the enzyme was partly inhibited in the presence of palmytoyl-L-a-lysophosphatidyl choline but that of amylodextrin (d, p, per reducing and nonreducing ends are 20.4 and 10. 3, respectively) was not inhibited by the lysolecithine at all.

粒状固定化酵素カラムによる可溶性でんぷんの加水分解

Guucoamylase was immobilized by amidination reaction on the granular polyacrilonitrile resin which had been preliminarily treated with dry HCl in methanol. The granular polyacrilonitrile resin was made by drop-wise addition of the dimethylf ormamide solution of polyacrilonitrile to methanol. Continuous hydrolysis of soluble starch was operated in a column which was packed with the immobilized glucoamylase (granularity : 1 mmφ). Estimated values of apparent MICHAELIS constant (Km) with the immobilized glucoamylase depended on flow rates in the column and were found to be higher than that with the native glucoamylase in the batch system. The immobilized glucoamylase column was connected in a series with a column of the immobilized a-amylase (granularity : 30-200 μmφ). And, a soluble starch solution was firstly passed through the immobilized α-amylase column and then through the immobilized glucoamylase column. The effect of the pretreatment of soluble starch in the immobilized α-amylase column on the rate of hydrolysis was recognized with regard to the balance between amount of immobilized α-amylase and the degree of the hydrolysis in terms of reducing sugar unit. A similar effect was observed in the pretreatment of soluble starch with native α-amylase in a batch system. The molecular weight distribution of the reaction product of α-amylase processing was analyzed by the gel filtration (Sephadex G-75)method for the higher molecular weight fraction and by the thin layer chromatographic method for the lower molecular weight fraction up to DP 12. On the basis of these results, the pretreatment with α-amylase was thought to be significant particularly in that the effective concentration of the substrate was increased through the fission of the glucoside chains. The endurance test of the immobilized glucoamylase column was pursued by the continuous operation for two weeks with a flow rate of 0.5 ml/min at room temperature and 40°C. Similar situations were referred to in the previous study was obtained.

Chemically activated collagen for amyloglucosidase attachment. Use in a helicoidal reactor.

Amyloglucosidase was covalently bound to collagen sheets by a previously described method. The time of acidic methylation (first step of the collagen activation process) was important to obtain a good enzymatic surfacic activity. Homogeneity of the coupling procedure on the surface of collagen films was shown. Some properties of free enzyme were not affected after grafting; optimum pH and temperature, activation energy, and Km for maltose. Heat stability of the bound enzyme was slightly better; Km for soluble starch increased fivefold. In contrast, the maximal velocity in the presence of soluble starch remained four times that of maltose hydrolysis. Amyloglucosidase collagen membranes were used in a helicoidal reactor to produce glucose from maltose or soluble starch solutions. Tracer studies have shown that the helicoidal reactor behaved as a CSTR. The influence of maltose concentration and flow rate on conversion was studied and confirmed the absence of diffusional limitations for maltose. Recycling of concentrated solutions of maltose and soluble starch indicated strong diffusional restrictions for soluble starch. The catalytic support kept all its activity for 18 days continuous operation at 40 degrees C and 80% after 17 months storage at 4 degrees C.

Microdetection of pharmaceuticals having amide, imide or amino groups on thin-layer chromatogram utilizing &lt;I&gt;tert&lt;/I&gt;-butyl hypochlorite

The plate was prepared with Silicagel G, Merck Co., suspended in 1.5% aqueous soluble starch solution. It was activated at 90°C for 1 h. Following solvent systems were employed in the development: A, petroleum ether-acetone-methylethylketone (8 : 1 : 1) ; B, chloroform-acetone (9 : 1) ; C, cyclohexane-acetone (3:1); D, carbon tetrachloride-99% ethanol (8 : 1) ;E, 99% ethanol-acetic acid-water (5 : 0.1 : 2) ; F, 99% ethanol-water (5 : 2). Solvent system A and B were proved to be excellent for the separation of amides and imides tested. Solvent system E was suitable for antibiotics. The plate was dried at 100°C for 15 min when the solvents A-D were used and for 30 min when solvents E and F were used. The dried plate was placed in a Petri dish in which two drops of 10% tert-butyl hypochlorite in acetic acid had previously been added. The plate was supported by a twisted glass rod and its silicagel layer should be faced towards the bottom of the dish to assure fast reaction with the vapor of the reagent. The Petri dish was immediately covered with its lid and allowed to stand for 2 min. The plate was then taken out and left for 10 min at room temperature to remove excess hypochlorite. The plate was sprayed with 1% potassium iodide to give blue-brown spots on a almost colorless background. The color was stable overnight when the layer was covered with polyethylene film.The present method was found to be markedly sensitive and simple. Limits of detection for barbiturates and hydantoins tested were 10 ng. On the other hand, antibiotics having amino sugar moieties showed limit of detection of 400 ng.

A Proposition for a Unified Method of Glucoamylase Activity Determination in Microbial Material

AbstractA unified method for glucoamylase activity GA determination in microbial material is presented and proposed. The method based on the enzyme action on a 2% soluble starch solution, 30 min 30°C at pH 4.5, and successive determination of the produced glucose by means of glucose oxidase‐peroxidase reagent. The suggested method is simple and facilitates serial analysis. The reproducibility of the assay is very good; the standard deviation from the mean is ± 2%. α‐Amylase present in the tested preparations in the amount up to 0.1 SKB units per 1 ml has no influence on the result of determination. The unit of glucoamylase activity (GA) has been defined as the amount of enzyme, which, in described conditions, will liberate 1 μmol of glucose from starch in the course of one minute.