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The purpose of the researchis to study the cumulative effect and subchronic toxicity of supramolecular complex of fenbendazole (SMCF).Materials and methods.The cumulative effect of SMCF was studied on 20 outbred white rats weighing 180 g that were divided into experimental and control groups of 10 animals each. SMCF was administered intragastrically to rats of the experimental groups for 24 days at the dose of 2000 mg/kg (1/10 of the previously established single LD50 (20000 mg/kg)) on the first day, then the dose was increased by 1.5 times every four day. The main criterion for evaluation of the results was the death of animals; we also observed the overall condition and behavior of rats. Subchronic toxicity was studied on 40 male white rats weighing 220–240 g. The animals were divided into 4 equal groups. The drug was administered daily to rats of the 1st, 2nd and 3rd experimental groups intragastrically using the doses of 1/5 (4000 mg/kg), 1/10 (2000 mg/ kg) and 1/20 (1000 mg/kg) of LD50 (20000 mg/kg) respectively for 7 days. The control group received 1% starch paste in an appropriate volume throughout the experiment. During the experiment, we observed physical signs and behavior of animals, food and water consumption; weight gains of animals on the 1st, 3rd, 5th and 7th days of the experiment. After the drug administration, animals were sacrificed by cervical dislocation. The laboratory examinations for hematological parameters and biochemical parameters were performed after treatment. Samples of organs (liver, heart, lungs, kidneys, spleen) were taken during necropsy to calculate mass coefficients and to make macroscopic examinations.Results and discussion. We found that the SMCF did not have any cumulative properties. The overall condition and behavior of rats was within the physiological range; animals consumed food and water and showed no signs of intoxication after oral administration of SMCF at doses of 1/5, 1/10 and 1/20 of LD50 for 7 days. The drug did not have influence on weight gains of animals. Hematological and biochemical parameters did not undergo significant changes and were comparable with the parameters of the control group. The mass coefficients of the internal organs did not differ statistically in experimental and control groups of rats.

Sodium trimetaphosphate (STMP) at different levels (1, 3 and 5%) was used to prepare cross-linked (CL) barnyard millet starch. The starches were studied for their physicochemical, pasting, steady shear rheological and thermal properties. Further, films were formulated from these starches and assessed for their functional and mechanical behavior. Amylose content of native starch (15%) decreased upon cross-linking (7.86–9.65%). CL starches had lower swelling power (SP) and solubility than native starch. CL starches showed lower peak (7049–9649 mPa.s), breakdown viscosities (BV) (1073–3172 mPa.s) but higher pasting temperature (PT) (79.7–80.8 °C) than native starch. Pasting properties were more affected for CL (5%) starch. Steady shear properties revealed lower yield stress (σo) values of CL starch pastes (1.39–2.37 Pa) than native starch paste (15.40 Pa). Flow behavior index was

Understanding how starch constituent in frozen dough affected bread quality would be valuable for contributing to the frozen products with better quality. To elucidate the underlying mechanism, starch was fractionated from multiple freezing-thawing (F/T) treated dough and reconstituted with gluten. Results showed that F/T treatment destructed the molecular and supramolecular structures of starch, which were more severe as the F/T cycle increasing. These structural disorganizations made water molecules easier to permeate into the interior of starch granules and form hydrogen bonds with starch molecular chains, which elevated the peak, breakdown, setback and final viscosity of starch paste. In addition, F/T treatment resulted in decreased specific volume (from 1.54 to 0.90 × 103 m3/Kg) and increased hardness (from 42.98 to 52.31 N) for steamed bread. We propose the strengthened water absorption ability and accelerated intra- and inter-molecular rearrangement of starch molecules and weak stability of “starch-gluten matrices” would allow interpreting deteriorated bread quality.

Pongamia pinnata seed (PPS) starch was studied for its physicochemical, thermal, rheological and morphological properties. As PPS starch is a novel starch, it was compared with corn, mung bean, potato, pearl millet and mango kernel starches. Peak, trough and final viscosity of PPS starch was found the lowest as compared to other starches. Plots of shear stress versus shear rate for starch pastes were plotted and fitted to Herschel-Bulkley model. Yield stress and consistency index value of starch pastes varied between 6.5 and 58.9 Pa and 1.4–10.6 Pa s, respectively. During frequency sweep testing, G′ and G′′ values of starch pastes varied between 33 and 484 Pa and 18–71 Pa, PPS starch paste had the lowest values. Transition temperatures (Tο, Tp, Tc) for PPS starch was 61.5, 72.1 and 82.9 °C, respectively. Scanning electron microscopy of PPS starch showed small to large and round to oval shape starch granules with small pitches on their surface.

This study aimed at exploring the effects of exogenous seed crystals on the starch recrystallization. A-type and B-type seed crystals from rice starch were added to rice starch paste during cooling to analyze the changes in retrogradation process. DSC results indicated that B-type seed improved the uniformity of crystal size and the degree of crystal perfection; it also affected the nucleation mode of retrograded starches at 4 °C, while A-type seed did not affect these properties. The XRD showed that the unit cell was compact, and the crystal grain became larger upon the introduction of B-type seed, while A-type seemed to loosen the cell. The SAXS reflected that B-type seed increased the thickness of the imperfect lamellar structure formed during recrystallization, while A-type seed decreased it. These findings might be due to the molecular segment arrangement on the nuclei growth surface affecting the arrangement of starch molecular segments approaching the nuclei.

The novel hyperbranched poly(trimellitic glyceride) (PTG) starch plasticizer synthesized in our previous study was neutralized with different alkaline metal hydroxides. Mixed with starch, the effects of different alkaline metal cations, M+, on gelatinization of starch suspensions and thermal behaviors of the films were analyzed using RVA and DMA, respectively. The structures of the starch suspensions, films and freeze-dried samples (S/PTG-M) were investigated using DSC, XRD and FTIR spectroscopy, respectively. M+ increased the gelatinization temperature of starch suspensions in the order of S/PTG-Li > S/PTG-Na > S/PTG-K. The formation of a complex between M+ and starch in the films observed using FTIR spectroscopy improved the stability of the starch paste and gel, and increased the gel temperature of starch dispersions. The corresponding starch gel was relatively thermostable, but not shear-resistant. PTG decreased the Tg of starch films with different paired M+. PTG-Li and PTG-K, but not PTG-Na, strengthened the mechanical properties of starch films.

The modification greatly improved konjac glucomannan (KGM) characteristics and expanded its application range. For this purpose, the combination of acidolysis with oxidation was chosen to modify KGM in a heterogeneous system. In this study, we mainly discussed the effect of acidolysis and oxidation on the structure and properties of KGM. The experimental results indicated that the acidolysis and oxidation destroyed the structure of KGM particles, and reduced its crystalline degree. The size of derivatives was greater than that of KGM, and their surface became very rough. The acidolysis and oxidation decreased obviously the swelling capacity of KGM, but increased the acid and alkali resistance. The thermal characteristic parameters of KGM such as onset decomposition temperature, onset temperature, peak temperature, enthalpy change, and so on were affected by the acidolysis and oxidation. The oxidation of hydrogen peroxide did not led to any carboxyl groups being introduced into KGM molecular chains, whereas it resulted in the reduction in the viscosity of KGM. There is no synergistic effect between KGM or its derivatives and starch paste.

The study was carried out in order to determine and establish the functional characters of starch extracted from yam bean (Pachyrhizus erosus (L) Urban) compared with cassava starch. Yam bean is a tropical tuber legume easily grown and holds a great potential as a new source of starch. Yam bean starch shows functional properties which are peculiar to those of most starch root crops. Gelatinization temperature (53-63 degrees C) and the pasting temperature (64.5 degrees C) are less than those of cereal starch, however, the swelling power is high (54.4 g gel/g dried starch). Yam bean starch paste presents a high viscosity profile, high retrogradation tendency and low stability on cooking. The functional properties of yam bean starch, similar to those of cassava starch, allows yam bean to be used as a potential new source of starch.

High pressure processing is a promising non-thermal technology for the development of fresh-like, shelf-stable foods. The effect of high pressure on starch has been explored by many researchers using a wide range of techniques. In general, heat and pressure have similar effects: if sufficiently high, they both induce gelatinization of starch in excess water, resulting in a transition of the native granular structure to a starch paste or gel. However, there are significant differences in the structural and rheological properties between heated and pressurized starches. These differences offer benefits with respect to new product development. However, in order to implement high-pressure technology to starch and starch-containing products, a good understanding of the mechanism of pressure-induced gelatinization is necessary. Studies that are published in this area are reviewed, and the similarities and differences between starches gelatinized by pressure and by temperature are summarized.

Starch paste viscosity plays an important role in estimating the cooking, eating, and processing quality of rice. The inheritance of starch paste viscosity in glutinous rice remains undefined. In the present study, 118 glutinous rice accessions were collected, and the genotypes of 17 starch synthesis-related genes (SSRG) were analyzed by using 43 gene-specific molecular markers. Association analysis indicated that 10 of 17 SSRGs were involved in controlling the rapid visco analyzer (RVA) profile parameters. Among these, the PUL gene was identified to play an important role in control of peak viscosity (PKV), hot paste viscosity (HPV), cool paste viscosity (CPV), breakdown viscosity (BDV), peak time (PeT), and paste temperature (PaT) in glutinous rice. Other SSRGs involved only a few RVA profile parameters. Furthermore, interactions between SSRGs were found being responsible for PeT, PaT, and BDV. Some of the RVA parameters, including PKV, HPV, CPV, CSV, and PaT, were mainly governed by single SSRG, whereas other parameters, such as BDV, SBV, and PeT, were controlled by a few SSRGs, functioning cooperatively. Further, three near-isogenic lines (NIL) of a japonica glutinous cv. Suyunuo as genetic background, with PUL, SSIII-1, and SSIII-2 alleles replaced with those of indica cv. Guichao 2, were employed to verify the genetic effects of the various genes, and the results were consistent with those obtained from the association analysis. These findings indicated that starch paste viscosity in glutinous rice had a complex genetic system, and the PUL gene played an important role in determining the RVA profile parameters in glutinous rice. These results provide important information for potentially improving the quality of glutinous rice.

An Onlator[○!R], a heat exchanger, was utilized as a continuous starch paste supplier for a fluidized-bed granulator. Ascorbic acid was used as a model drug substance and cornstarch as the binder. To control the temperature of cooking starch paste, modes of proportional control (P control) and proportional integral deviation (PID control) were used to distinguish their respective effects on the tablet properties. It was shown that the PID control caused less variation in the temperature of cooking starch paste and, in accordance with this, that variation in disintegration time for the resultant tablets was less. there was, however, little difference in tablet hardness between these two modes of control.

Particle size distribution of fine granules produced by agitation granulation was investigated as a function of the concentration of starch paste. The time course of granulation was investigated in a high speed type mixer using 5% starch paste having a good fluidity and 15% starch paste having no fluidity at all, like a gel. In agitation granulation, aggregation and deaggregation of particles and/or granules occurred simultaneously.At a low concentration of starch paste, massing of the granules, namely the growth of granules, occured mainly during the agitation granulation, since the relatively large amount of free water was available from the paste. Therefore, in this case, only the mean size shifted toward a larger measurement without any change in the width of the granules during the granulation.At a high concentration of starch paste, rapid deaggregation of granules by shear force applied occurred following the formation of large granules immediately after the addition of paste. Since a small amount of water exudes from the paste during the agitation, massing proceeds slowly. This means that in the case of granulation using a high concentration of starch paste, deaggregation proceeds predominantly, so that the size distribution of the granules becomes more narrow. Fine granules may be produced by agitation granulation when a high concentration of starch paste is used and when granulation is executed under sufficient shear or rotation speed that guarantees satisfactory dispersion of the gel.

The critical concentration of a starch paste is the limiting concentration above which structural flow is apparent. The inverse of the critical concentration, termed the effective volume, is the minimum volume of solution per gram of starch below which structural flow is apparent. The critical concentrations and effective volumes have been measured for series of pastes of acid-modified corn and potato starches, and the effective volume has been shown to decrease with increasing degree of modification. The specific viscosities per unit concentration of these pastes, at concentrations below the critical, increases linearly with the effective volume, and the proportionality constants found are compared with those derived from the equations of Einstein and of Hatschek. The effects of phase-volume ratio and ease of deformation of the dispersed phase on the viscosity of a system are discussed, and previous relations applied to experimental data obtained in the present instance. Residual structure below the critical concentration is discussed. Above the critical concentration, the viscosity is dependent on the rate of shear, and the equation F = KPn expresses the experimental data well, where F is the flow, P is the pressure, K and n are constants. For two starches investigated, within the range of concentrations used n has been found to increase linearly with the concentration c, dn/dc being dependent on the elasticity or deformability of the granules.The form of lyophilic colloids in solution is discussed and agreement is expressed with the conception of Haller that the long-chain molecules, owing primarily to the free rotatability of the valence linkages, are irregularly bent and tangled in solution, as opposed to Staudinger's conception of straight rigid chains. These molecules occupy on the average a form approximating to the spherical, and solvation is due chiefly to immobilization. A dextrin in solution was found to have a [Formula: see text] ratio close to that of a pasted starch, and the forms of the two are probably similar. A lyophilic sol is considered heterogeneous and similar in many respects to an emulsion, with a very highly deformable discontinuous phase. The viscosity of such a system is due to phase-volume relations, modified by the ease of deformation of the dispersed phase, and the particular characteristics of these important sols admit of explanation on this basis.

1. 1. Measurement of the flow properties of starch pastes with the precision and accuracy required for industrial purposes is feasible. The methods described utilize the Corn Industries viscometer and a modified Stormer viscometer. The former provides a continuous record of the change in flow properties during pasting at a controlled cooking temperature; the latter supplements the data obtained during pasting with a rate of shear-shearing stress curve from which the apparent viscosity, expressed in poises, can be computed at any given rate of shear. 2. 2. Rheological data on a variety of commercial starches were obtained. The effect of rate of shear, concentration of the starch, and other factors are discussed. In all cases a curve typical of pseudoplastic flow was obtained. 3. 3. Continuous decrease in apparent viscosity occurs during the pasting process with the greatest change in the first hour; for many starches a fairly level viscosity is obtained after one hour cooking at 90–92°C. Vigorous agitation, in contrast to that obtained with low-speed sweep agitators, produces a more rapid decrease in viscosity, but differences in agitation apparently do not alter the nature of the pasting process. 4. 4. The effect of rate of shear on the computed values for apparent viscosity is great. Satisfactory measurements can be made only when the rate of shear is constant or when the magnitude can be determined and specified. The measuring methods described are reproducible and characterize the starches with respect both to rate of pasting and the flow properties of a given paste at different rates of shear. Industrial measurements can be made more precise by these means, and discrepancies in standardization and grading can be largely eliminated.

A new mothod for examining the disintegration of a tablet and a granule continuously and in detail was proposed. The beginning of disintegration, the time necessary for the maximum surface area of tablet ingredient, and the time required for a powder to dissolve completely were determined precisely. This method was applied to the tablet of calcium carbonate in the acetate buffer of pH 4.2 and the following conclusions were drawn. a) The tablet prepared from CaCO3 powder by direct compression disintegrated and dissolved very rapidly, and difference between the original powder and the tablet was not recognized. b) The disintegration and solution rate of CaCO3 granule that contained starch paste was not rapid and larger particles remained undissolved in the final stage. c) It was evidenced that the tablet prepared from CaCO3 granule disintegreted more slowly than the tablet prepared by direct compression.

THE wartime importance of starch makes interesting some of the recent advances made in the study of this carbohydrate in different countries. In India, where the cowpea ( Vigna catjang ) is an important food crop, studies of its properties have been made (2). Analysis of seeds from the long-podded variety showed 39.2 per cent starch and 11.12 per cent soluble carbohydrate. Methods similar to those used commercially in producing cereal starches were applied to the cowpea in the laboratory, and the yields were 20 per cent white starch (87.3 per cent starch, 10.02 per cent moisture, and 0.14 per cent ash) and 74.4 per cent pulp (36.22 per cent protein, 23.1 per cent crude fiber, 27.55 per cent starch, 8.17 per cent moisture, and 4.4 per cent ash). A 3 per cent cowpea starch paste heated to 90° C had a viscosity somewhat higher than that of wheat starch, but lower than that of Indian corn ...

THE introduction of a satisfactory chemical method for the early debridement of burns would simplify a perplexing problem. For many years attempts have been made to find some agent that would selectively digest or remove the necrotic slough that follows severe burning. Since Connor and Harvey1 in 1944 first reported the use of pyruvic-acid starch paste as a suitable agent, few clinical reports have been published on the use of this method of debridement. With a severe burn the open wound is largely responsible for serious electrolytic and protein aberrations resulting from the tremendous loss of serum. The persistence of . . .