bluuebunny/crossref_metadata_2025_split huggingface dataset:
Catalytic Properties of Bacillus megaterium Amylase
Authors: David M.‐H. , Günther H. , Röper H. 
Published: November 2006

AbstractA new amylolytic enzyme from Bacillus megaterium is described, which is produced as a trace contaminant in a complex protein mixture, with β‐amylase as the major enzyme. By genetic engineering, the productivity could be increased by a factor 10000, and the enzyme is free of other amylases. Compared to pullulanase, which catalyses pullulan degradation to maltotriose, B. megaterium amylase (BMA) does not attack 1,6‐linkages and hydrolyses pullulan exclusively to panose. Furthermore, it hydrolyses crosslinked Phadebas starch, used for determination of α‐amylases and it also catalyses transfer reactions. Those are strongly enhanced in presence of suitable acceptors, which can be sugar molecules with the same configuration as dextrose in C2, C3, C4‐position. In the industrial dextrose process, about 1% of oligosaccharides remains from starch which is difficult to be hydrolysed, thus reducing yield and quality of the final product. The structure elucidation showed 35% 1,6‐linkages being present. These oligosaccharides can be degraded and eliminated by BMA through panosyl transfer to dextrose, under formation of 63‐α‐glucosylmaltotriose, which is degraded by glucoamylase to dextrose.
Properties of Starches Isolated from Western Samoan Breadfruit Using a Traditional Method
Authors: Tumaalii F. , Wootton M. 
Published: November 2006

AbstractStarches were isolated from the pulp of seven varieties of mature Western Samoan breadfruit using a traditional method. Proximate analysis, starch damage and amylose contents were measured. Isolated starches were further examined by image analyser to determine particle size distribution and by X‐ray diffraction. Gelatinisation was studied by Visco‐Amylograph, and by swelling power and solubilisation during heating in water. The starches were as low in non‐starch materials except protein (0.37‐ 1.08%) as commercial starches from most other sources. Breadfruit starch showed the B‐type X‐ray diffraction pattern common in tuberous starches and resembled potato starch in its gelatinisation behaviour. Variations in particle size, gelatinisation behaviour, starch damage and amylose level existed between starches from the different varieties and would influence selection as a starch for specific purposes.
Auswirkungen einer Feuchtkonservierung von Mais auf die Stärkequalität
Authors: Haase N. U. , Kempf W. 
Published: November 2006

AbstractDie Maisstärkegewinnung aus einheimischem Körnermais ist mit Einschränkungen möglich. Aufgrund von Feuchtegehalten der Körner zwischen 30 und 40% bei der Ernte wurde statt einer Trocknung eine Feuchtkonservierung erprobt. Bei den Versuchen mit Natriumhydrogensulfit traten hinsichtlich der qualitativen Aspekte der isolierten Stärken über die Versuchsdauer von 24 Wochen keine wesentlichen Unterschiede zu nicht gelagerten Referenzstärken auf. Die Silierung von Maiskorn‐Spindel‐Gemischen in Form einer Milchsäuregärung führte ebenfalls zu Stärken einer gleichmäßig guten Qualität. Somit sind beide Formen der Feuchtkonservierung als vorgeschaltete Lagerungsverfahren der Maisstärkegewinnung geeignet.
Absolute Measurements of the Rheological Properties of Gelatinized Starches.
Authors: Windhab E. , Tegge G. , Tiemeier U. 
Published: November 2006

AbstractDie Beschreibung des rheologischen Verhaltens von Stärkepasten wird im allgemeinen auf der Grundlage von Messungen vorgenommen, welche nur die empirische Beurteilung zulassen. Der Grund dafür ist die Verwendung von Meßgeräten, die keine rheometrische Strömung realisieren. Unter Verwendung von Absolutrheometern (Rotations‐und Kapillarrheometer) ist es möglich, bei Berücksichtigung der rheologischen Parameter, Zeitverhalten (Thixotropie) und Wandgleitverhalten, reproduzierbare geräteunabhängige Fließfunktionen zu bestimmen. Die Fließgrenze verkleisterter Stärkepasten als wichtiger charakteristischer Parameter zur Kennzeichnung der “dickenden” Wirkung wurde mittels einer neu entwickelten Meßeinrichtung gemessen. Auf der Grundlage dieser Meßtechnik erfolgte die Quantifizierung des Einflusses der Parameter: Kochzeit, Stärkekonzentration, Stärkeart, Temperatur und Alter der Stärkepaste auf die rheologischen Kenngrößen der Stärkepasten.
Benefits of Bacillus megaterium Amylase in Dextrose Production
Authors: Hebeda R. E. , Styrlund C. R. , Teague W. M. 
Published: November 2006

AbstractA Bacillus meguterium amylase (BMA) has the ability to convert branched saccharides to a form that is easily hydrolyzed by glucoamylase. Concequently, dextrose production can be improved by using a combination of BMA and glucoamylase in saccharification. Benefits provided by BMA are similar to those achieved with a debranching enzyme. For instance, BMA is effective in increasing dextrose yield, while at the same time, nearly eliminating tetra‐ and higher saccharides. BMA can also be used to increase saccharification rate, reduce glucoamylase dosage, or maintain normal dextrose level at higher solids. Benefits of BMA have been quantified by evaluating the enzyme in combination with glucoamylase using typical industrial saccharification conditions.
Graft Copolymerization of Acrylonitrile on to Guar Gum by Hydrogen Peroxide Initiation
Authors: Raval D. K. , Patel R. G. , Patel V. S. 
Published: November 2006

AbstractGrafting of acrylonitrile on to guar gum by hydrogen peroxide initiation in aqueous media was achieved at different reaction conditions. Effects of hydrogen peroxide concentration and the amount of guar gum on grafting parameters have been discussed. Increasing H2O2 concentration (i. e. from 5 mmol to 20 mmol) increased the conversion of monomer and % add‐on, whereas the average molecular weight of grafts and the grafting frequency decreased. An increase in the amount of guar gum also increased the conversion of monomer and grafting frequency but decreased the % add‐on and increased the average molecular weight of the grafts. The graft copolymer is also characterized by infrared spectrophotometry.
Coupling Reaction of Bacillus macerans Cyclodextrin Glucanotransferase on Glucosyl‐α‐cyclodextrin and Glucose
Authors: Kobayashi S. , Ashraf H.‐R. Lee , Braun P. , French D. 
Published: November 2006

AbstractTreatment of glucosyl‐α‐cyclodextrin with radioactive glucose in the presence of Bacillus macerans cyclodextrin glucanotransferase, yielded radioactive maltose, maltotriose, and four kinds of glucosyl branched oligosaccharides. The branched oligosaccharides formed had identical Rf values as those of branched oligosaccharides of 5‐8 glucose unit on paper chromatography using the solvent system of 1‐butanol: pyridine: water (6/4/4), (Fractions B5‐B8). Individual oligosaccharides were isolated and their structures determined using the action of porcine pancreatic α‐amylase, β‐amylase, pullulanase, isopullulanase and glucoamylase. The structure of the main component of the fraction B5 was 64‐O‐α‐glucosylmaltotetraose, B6 was 64‐O‐α‐glucosylmatopentaose, B7 was 65‐O‐α‐glucosylmaltohexaose, and B8 was 66‐O‐α‐glucosylmaltoheptaose. Fraction B8, which formed at the initial stage of the reaction, contained 64, 65 and 66‐O‐α‐glucosylmaltoheptaose. Reducing end 14C‐labelled 64‐O‐α‐glucosylmaltotetraose was degraded to 63‐O‐α‐glucosylmaltotriose and radioactive glucose by the exhaustive action of Bacillus macerans cycloamylose glucanotransferase, and 63‐O‐α‐glucosylmaltotriose was completely non‐reactive to the enzyme. From these results, we proposed a model of the active site of the enzyme.
Beseitigung von Weizenstärkeindustrie‐Abwässern – Ein Wirtschaftlichkeitsvergleich
Authors: Witt W. , Kröner H. 
Published: November 2006

AbstractDie Produktion von Weizenstärke spielte an der Gesamtstärkeproduktion aus Mais, Kartoffeln und Weizen in der Vergangenheit eine untergeordnete Rolle. Neue Verfahrenstechniken zur Gewinnung von Weizenstärke sowie entsprechende EG‐Marktregelungen lassen die Produktion von Stärke aus Weizen bzw. Weizenmehl in jüngster Zeit interessanter erscheinen. Aufgrund der größeren Verarbeitungsleistung in Weizenstärkefabriken sind daher alternative Abwasser‐Behandlungsmethoden zu der Verregnung gefragt. Hier sind zu nennen die vollbiologische Reinigung in einer Belebungsanlage, die Eindampfung, Filtration, Eiweißkoagulation, Vermarktung als Viehfutter, Fermentation und die anaerobe Reinigung. Welche dieser Abwasserbehandlungsmethoden sich großtechnisch durchsetzen, hängt nicht nur von der Verfahrenstechnik und der Reinigungsleistung, sondern auch wesentlich von der Wirtschaftlichkeit ab. Hier rückt in letzter Zeit die anaerobe Reinigung organisch hochbelasteter Abwässer immer mehr in den Vordergrund. Ein Vergleich der verschiedenen Behandlungsmethoden zeigt, daß die Kosten sehr stark vom Abwasserfaktor, d. h. der Abwassermenge pro Tonne verarbeitetes Mehl, und den Strom‐ bzw. Energiekosten abhängig sind. Bei der Berechnung der Kosten müssen Kosten für eine evtl. Nachklärung in einer kommunalen Kläranlage und Erlöse für Biogas oder Konzentrat berücksichtigt werden.
Change in Digestibility of Gamma‐Irradiated Starch by Low Temperature Cooking
Authors: Kume T. , Rahman Saifur , Ishigaki I. 
Published: November 2006

AbstractCombination effect of irradiation and low temperature cooking on starch digestibility has been investigated as a basic research for application of radiosterilization on starch fermentation. The digestion of corn starch by glucoamylase after cooking at low temperature was enhanced by γ‐irradiation and the required cooking temperature was decreased from 75‐80°C to 65°C by 25 kGy. Gelatinization of starches except tapioca starch was enhanced by irradiation and it corresponds to the digestibility. The digestibility of potato starch which has a high viscosity was especially enhanced at low temperature cooking because the viscosity was markedly decreased by irradiation. These results show that the irradiation of starches is useful not only for the sterilization of fermentation broth but also for the enhancement of digestion.
Structure and Properties of Water Chestnut (Trapa natans L. var. bispinosa Makino) Starch
Authors: Hizukuri S. , Takeda Y. , Shitaozono T. , Abe J. , Ohtakara A. , Takeda C. , Suzuki A. 
Published: November 2006

AbstractThe Brabender amylogram (6% concentration) of water chestnut (Trapa natans L. var. bispinosa Makino) starch showed that its pasting temperature was 71°C and its viscosity was low (max, 310 B. U.) which remained constant during heating and increased slightly on cooling. The starch showed a Cc or Ca type X‐ray diffraction pattern, and the susceptibility of the granules to amylases was intermediate between those of corn and potato starches. The number‐ and weight‐average degrees of polymerization (D.P.) of the amylose were 800 and 4210, respectively. The apparent d. p. distribution was 160–8090. The amylose was composed of 3 components differing in molecular size and the number of chains, and 89%, by number, of the molecules were linear. The amylopectin contained 44 ppm of phosphorus, and its number‐ and weight‐average chain lengths were 22 and 26, respectively.
Gel Chromatography of Residue and Extract Obtained from Starch Granules by Hot Aqueous 1 ‐Butanol Solution Treatment
Authors: Taki M. , Suzuki K. , Taki A. , Hisamatsu M. , Yamada Tetsuy A. 
Published: November 2006

AbstractStarch granules of corn starches (normal, waxy, amylo and amylowaxy) and potato starch were treated with hot aqueous solution saturated with 1‐butanol and fractionated. These fractionated starches were subjected to an advanced gel chromatography with a column system of Toyopearl HW 75 F. Amylose of normal maize and potato starches was perfectly leached out from the granules, but that of amylo maize was not perfectly extracted. Amylo and amylowaxy maize starches were proved to have large amount of low‐molecular weight material. Normal and amylo maizes, and potato starches contained a high‐molecular‐weight material recognized as amylose type, and it is strongly suggested that amylopectin of normal maize is not same as that of waxy maize. It was found that the GPC analysis was a very important step to estimate an amylose content since a part of amylopectin made a precipitable complex with 1‐butanol.
Effect of the Hard‐to‐Cook Phenomenon on Some Physicochemical Properties of Bean Starch
Authors: Paredes‐López O. , Maza‐Calviño E. C. , Montes‐Rivera R. 
Published: November 2006

AbstractTwo bean varieties of outstanding agronomic performance were seeded, harvested and a portion stored for 135 days under high temperature and humidity. These varieties were Negro Qro and Canario with black and light yellow seeds, respectively. Hard‐to‐cook (HTC) defect developed in aged seeds as assessed by the Mattson cooker and Instron texturemeter. Fresh and HTC beans were used in order to determine physicochemical changes in starch and to evaluate its contribution in textural defects. The damaged starch content, water absorption and swelling were higher for isolated starches from HTC seeds than for the controls. Starch damage was generated by enzymatic attack and/or by mechanical action during milling. Pasting properties examined with the Brabender viscograph showed that peak viscosity increased and stability and retrogradation capacities declined after storage. These results might be ascribed to the starch damage and also to changes undergone by the residual impurities of isolated starches. In agreement with the previous observations, scanning electron microscopy of starch isolated from HTC samples revealed the presence of some swollen granules and many others with fissures, while those from controls had smooth surfaces and with no evidence of damage. Differential scanning calorimetry (DSC) evaluations showed that gelatinization temperatures and transition enthalpies were not significantly influenced by storage; results in agreement with birefringence studies. It is suggested that the changes in the starch from defective seeds were not sufficient to modify the gelatinization performance.
Rheological Properties of Leucaena glauca Gum in Aqueous Solutions
Authors: Raval D. K. , Patel R. G. , Patel V. S. 
Published: November 2006

AbstractThe flow properties of Leucaena glauca gum solutions were studied in the range of shear rates 1.5 to 1310 s−1, using a rotational viscometer Rheotest 2. The flow behaviour of aqueous solutions of the polysaccharide is pseudoplastic, and transition from Newtonian to pseudoplastic behaviour occurs in the low shear rate range at concentrations of interest to the industry. The flow of polysaccharide solutions is described by equation of state proposed by M. M. Cross. The basic rheological parameters, like zero shear rate viscosity (ηo), infinite shear rate viscosity (ηα) and a constant associated with the rupture of linkages (α) were calculated applying simple and established relations. The effect of concentration and temperature on rheological parameters have been studied. The Cross equation is found to be applicable to the data with a good degree of accuracy over a wide range of shear rates.
Synthesis and Properties of Polyacrylamide‐Starch Graft Copolymers
Authors: Hebeish A. , Bayazeed A. , El‐Alfy E. , Khalil M. I. 
Published: November 2006

AbstractGraft polymerization of acrylamide onto rice starch was investigated under different conditions using potassium persulphate, benzoyl peroxide or potassium permanganate as initiator. This has led to establishment of the most appropriate grafting conditions for each of these initiators. Under these conditions grafting was characterized by two rates regardless of the initiator used. The first rate occurred during the initial stages of polymerization while the second during the later stages. The first rates of grafting for the three initiators were very close indicating the insignificant effect of the nature of the initiator on grafting during the initial stages of the reaction. On the other hand, the second rates of grafting exhibited the order: potassium persulphate < benzoyl peroxide < potassium permanganate, reflecting the role played by the nature of initiator during the later stages of the reaction. Substantial differences in solubility were observed between polyacrylamide‐starch graft copolymers and unmodified starch as well as among copolymers prepared using the three initiators. Although the copolymers acquired higher solubility percent than the unmodified starch, yet nature of initiator, graft yield, structural changes in the copolymer occuring during grafting and the temperature of solubility measurement determined the solubility percent. Copolymers prepared using benzoyl peroxide or potassium persulphate showed lower viscosity than the unmodified starch. The opposite was the case with respect to copolymer prepared using potassium permanganate.
Neuer Erkenntnisse zur Struktur des Wassers in der Stärke
Authors: Lechert H. , Scoggins W. C. , Basler W. D. , Schwier I. 
Published: November 2006

AbstractUntersuchungen der Protonen‐ und der Deuteriumresonanzlinien an Wasser in Kartoffelstärkeproben zeigen eine Aufspaltung, die bei etwa 1% des Wertes der statischen Aufspaltung liegt und eine anisotrope Umorientierung der Wassermolekeln andeutet. Diese Einschränkung der Wasserbeweglichkeit erfolgt bis zu einem Wassergehalt von etwa 50% H2O/TS entsprechend einer Wasseraktivität nahe eins. Der weite Bereich dieser Beeinflussung und die geringe Breite der Komponenten insbesondere der D‐Resonanzen legen die Annahme eines weitestgehend einheitlichen Bewegungsmechanismus der Wassermolekeln nahe. Niedrige Selbstdiffusionskoeffizienten und Unempfindlichkeit der Linienformen gegen das Ladungs‐Radius‐Verhältnis sowie paramagnetische Momente eingetauschter lonen scheiden eine translatorische Beweglichkeit als Mittelungsmechanismus über das Stärkekorn aus. Verschiedene Möglichkeiten der Rotation der Wassermolekeln werden für diese Mittelung diskutiert. Die beobachteten Effekte lassen sich durch die Annahme von Tetraedersprüngen des Wasserstoffs in einer Matrix geringer translatorischer Beweglichkeit der Wassermolekeln deuten. Vergleichende Untersuchungen an deuterierter Baumwolle machen eine bevorzugte Orientierung dieser Bewegung längs der Helixachsen wahrscheinlich.
Scanning Electron Microscopy Study of Starch Granule Degradation in Chick‐Pea Cotyledons. Influence of Endogenous Dihydrozeatin and Calcium Chloride on Degradation Processes
Authors: Rodríguez A. , Villalobos N. , Nicolás G. , Martín L. 
Published: November 2006

AbstractTreatment of excised cotyledons with both endogenous dihydrozeatin (DHZ) and Ca2+ or Ca2+ plus the ionophore A‐23187 produces a similar effect to that of the embryonic axis on the catabolism of starch granules. Under the three kinds of treatment a progressive degradation of the granules occurs from the adaxial to the abaxial zone on the 4th day of incubation and by the 10th day the starch polyhaedrals that are characteristic of seeds on the 10th day of germination are observed.
Crosslinked Starch Entrapped in Agarose‐Beads. An Affinity Matrix for the Preparation of α‐D‐Mannose/α‐D‐Glucose Specific Lectins
Authors: Sawhney S. Y. , Nandedkar U. N. , Bhide S. V. , Kale N. R. 
Published: November 2006

AbstractA simple biospecific affinity matrix like crosslinked starch entrapped in agarose‐beads is used for the isolation of α‐D‐mannose/α‐D‐glucose specific lectins such as Concanavalin A. pea and lentil. The adsorption capacities of these lectins for crosslinked starch are compared with those of Sephadex G‐50. The purified lectins were found to be identical to those obtained by using Sephadex G‐50 as an affinity matrix, as judged from their electrophoretic patterns (PAGE ‐ pH 4.5, SDS‐PAGE) and hemagglutination of papain treated rabbit erythrocytes.
Modified Starch‐Natural Rubber Blend. Effect of Cyanoethylation of Starch Xanthide on Biodegradability of Vulcanizates
Authors: Hota A. K. , Maiti M. M. 
Published: November 2006

AbstractBiodegradability of starch xanthide‐ and cyanoethylated starch xanthide ‐ natural rubber vulcanizates ‐ has been studied by subjecting them to field tests. It has been observed that resistance to biodegradation increases with the degree of substitution of starch. Cyanoethyl group as the substituent appears to offer much higher resistance to biodegradation than xanthide groups.
Die Beziehung zwischen dem Gehalt an Stärke und an Kalium in Kartoffelknollen
Authors: Miča B. 
Published: November 2006

AbstractDie Beziehung zwischen dem Gehalt an Kalium und dem Gehalt an Stärke in Kartoffelknollen wurde untersucht. Es wurde festgestellt, daß bei einer Auswertung die Angaben in Prozent der Frischsubstanz deutlichere Ergebnisse zeigen als die Angaben in Prozent der Trockensubstanz. Die statistische Auswertung zeigt, daß die Beziehung Kalium: Stärke hoch positiv gesichert ist (in % der Frischsubstanz) und daß diese Beziehung dagegen in % der Trockensubstanz negativ hoch gesichert ist.
A Histological and Histochemical Study of Starch Granule Degradation in the Cotyledons of Lens culinaris
Authors: Revilla M. A. , Fernández Tárrago J. 
Published: November 2006

AbstractThe pattern of starch granules degradation and amylase development in cotyledons of Lens culinaris Medik var. Castellana, was investigated by means of fluorescence microscopy and starch film method, respectively. Starch granules degradation in lentil cotyledons during germination started at the peripheral abaxial side and advanced towards the internal adaxial side of the cotyledon. However, amylase activity development took place from the whole periphery towards the center of the cotyledon. These results show the absence of a relationship between the zone of amylase activity and the degradation of starch granules. The absence of an embryonic axis did not affect the location of amylase activity but, on the other hand, did hinder the degradation of starch.
Gelatinisation and Liquefaction of Cassava Flour: Effect of Temperature, Substrate and Enzyme Concentrations
Authors: Vijayagopal K. , Balagopalan C. , Moorthy S. N. 
Published: November 2006

AbstractThe effect of concentration and temperature on the gelatinisation of cassava flour was studied. It was found that at the same temperature, higher concentration of flour led to higher viscosity and early gelatinisation. Increasing concentration also resulted in higher breakdown in viscosity. Temperature increase brought about increase in viscosity. These results showed that viscosity depended both on concentration and temperature. The effect of α‐amylase on gelatinisation and liquefaction of cassava flour was also examined. Three concentrations of the enzyme were tried on three flour concentrations. The amount of enzyme required for liquefaction and the temperature to be used for gelatinisation‐liquefaction in presence of amylase, appeared to be less than previously reported.
The Development and Properties of the of the Potato (Solanum tuberosum L.). The Pattern of Growth in the Field: Bolbography
Authors: Meredith P. 
Published: November 2006

AbstractA technique is demonstrated for the study of the growth of the population of tubers in a potato crop. Results suggest that many periods of initiations occur and that tubers tend to grow as cohorts of similar size from common initiation events. There is a compaction of the range of tuber sizes during the maturing period in the ground after senescence; this observation may be of commercial importance.