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Starch modification by chemical reaction is widely used to improve the properties of native starch. Modified by citric acid, starch is characterized by specific properties resulting from the presence of citrate residues and as a result of cross-linking starch. The chemicals used for preparing starch citrates are safe for human health and the natural environment compared to the harsh chemicals used for conventional modifications. Starch citrates are traditionally produced by heating starch–citric acid mixtures in semi-dry conditions or by a heat moisture treatment. The conditions of the modification process (roasting temperature, heating time, citric acid dose) and the botanic source or genotype of starch determine the degree of substitution and the properties of the obtained preparations. Changes of starch properties occurring during esterification lead to reduced relative crystallinity, resulting in a decrease in the affinity for water, the gelatinization parameters, and the viscosity of starch citrate. However, one of the most important outcome of the modification is the formation of resistant starch (RS), which has increased resistance to the action of amylolytic enzymes. Currently, new methods for producing starch citrates with improved functional and rheological properties while maintaining the highest possible content of resistant starch are being sought. The article presents an overview of recent studies on the production, properties. And applicability of starch citrates with special attention paid to their role as preparations of resistant starch (RS). The use of citric acid for modification of starch is better for the technology process, while using cross-linking is better than simply using esterification.

The Arabian leopard (Panthera pardus nimr) is critically endangered by the International Union for Conservation of Nature, with an effective population of 150-250 across its entire range in the Arabian Peninsula. Isolation and preservation of multipotent mesenchymal stem cells is beneficial both for medical and research purposes. The optimal protocol for collection, handling, culturing and preserving the Arabian leopard mesenchymal stem cells acquired from bone marrow was established. Anesthesia with combination of medetomidine and tiletamine-zozalepam is the safest option even for old animals with concurrent disease including chronic kidney disease.Keywords: Anesthesia, Arabian leopard, Bone marrow, Mesenchymal stem cells, Panthera pardus nimr

Objective: An article on the acceptance of a custom designed Intraosseous Transcutaneous Amputation Prosthesis (ITAP) fitted to the left hind limb of a female Arabian tahr (Arabitragus jayakari) and the factors needed to optimize recovery, rehabilitation and successful reunion with the herd. Study Design: A Case Report. Sample Population: A 4 year old, 15kg Arabian female tahr from the Omani Mammals Breeding Centre. An implant was inserted 4 months after amputation of the hind left leg at the level of one third distal tibia. Method: The distal limb amputation was due to a trauma allowing the possibility to insert the custom designed ITAP into the tibia. 2 weeks after the surgery an exoprosthesis was attached to the limb. 3 months post implantation a myiasis complication was observed in the junction between the skin and the implant. Immediate, aggressive treatment prevented implant infection and failure. The outcome of the surgery was measured by means of subjective assessments of the limb function and radiographic examination. Results: Skin integration with the ITAP was achieved within 28 days and shortly after the attachment of the exoprosthesis the Arabian tahr exhibited no signs of discomfort whilst walking. The tahr was successfully reunited with the breeding herd. Conclusion: Application of the ITAP to the left tibia of the Arabian tahr resulted in positive functional outcomes. 6 months post-surgery observations confirmed ambulation was restored in a pain free manner. Reintroduction to the breeding group continues to ensure conservation of endangered species. Clinical Relevance: ITAP offers a viable option to restore functionality and ambulation in wildlife despite possible post amputation problems thus saving individual animals contributes to conservation and breeding programs of endangered species.

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The study was aimed on the determination of biodegradation rate of extruded starch carriers, with or without immobilized microorganisms in diversified storage conditions. The research was conducted on potato starch, in which Saccharomyces cerevisiae yeast cells were immobilized. Preparations with and without yeasts were than placed for 84 days in the environments of: light soil, heavy soil, compost, water and activated sludge. After 0, 7, 14, 21, 49 and 84 days of storage the preparations were perfused with water and analyzed. In the recovered samples the following tests were carried out: the force causing fracture, the elongation caused by the mentioned force, the mass and the diameter of the carrier. Due to the degradation the size and the mechanical properties of the samples were decreased. The rate of the degradation was strongly dependent on the environment of the storage. The fastest degradation of the carriers were observed for compost and heavy soil, while the slowest biodegradation was observed for the samples placed in the water environment. The rate of biodegradation was also influenced by the Saccharomyces cerevisiae yeasts. The rate of biodegradation was faster in the samples containing yeast cells, than in the extrudates without the microorganisms.

Celem pracy było określenie czasu i warunków przechowywania na właściwości ekstrudatów otrzymanych ze skrobi oraz mieszaniny skrobi i kaolinu. Skrobię ziemniaczaną oraz mieszaninę skrobi ziemniaczanej i kaolinu w ilości 50% poddano procesowi ekstruzji w jednoślimakowym ekstruderze firmy Brabeder – typ 20DN. Wytworzone preparaty przechowywano w komorze suszarniczej oraz w komorze klimatycznej przez okres: 1, 3, 6, 9, 14 i 21 dni. Po tym czasie w ekstrudatach określono: zawartość wody, stopień ekspansji, odkształcenie przy złamaniu oraz moment gnący. Właściwości preparatów różniły się w zależności od rodzaju ekstrudowanej mieszanki oraz czasu i warunków przechowywania. Ekstrudaty wytworzone z mieszanki z dodatkiem kaolinu charakteryzowały się mniejszą ekspansją, mniejszym pochłanianiem wilgoci oraz mniejszym odkształceniem w chwili złamania i mniejszym momentem gnącym w porównaniu z ekstrudatami wytworzonymi z naturalnej skrobi ziemniaczanej. Preparaty przechowywane w warunkach większej wilgotności odznaczały się większym stopniem ekspansji oraz mniejszym odkształceniem i mniejszym momentem gnącym w stosunku do preparatów przechowywanych w niższej wilgotności.

The objective of this study was to establish the effect of the concentration of a starch paste subjected to freezing on the properties of the produced retrograded starch, and to determine its susceptibility to acetylation with acetic acid anhydride. A starch paste (1, 4, 10, 18 or 30 g/100 g) was produced from native potato starch that was frozen, defrosted and dried. Al preparations of retrograded starch had the same chemical structure determined with the technique of nuclear magnetic resonance (NMR) and diversified physical form visible on photos taken with an electron microscope (SEM). An increase in the concentration of paste, used to produce the preparations, resulted in decreased: amylose content (from 25.0 to 20.4/100 g), solubility in water (from 41.1 to 20.1/100 g), swelling power (from 45.0 to 19.3/g), and susceptibility of the preparations to the action of amyloglucosidase (from 95.4 to 83.6/100 g). The heat of phase transition of solubilisation determined with differential scanning calorimetry (DSC) ranged from 3.8 to 7.1 J/g, and the initial temperature of transition was increasing from 43.4 to 49.7 °C along with an increasing concentration of the paste subjected to retrogradation. The 1–10/100 g concentration of the paste used to produce preparations was observed to increase, whereas that between 10 and 30/100 g to decrease the susceptibility to acetylation and viscosity of the prepared pastes, determined both with a Brabender viscograph and a Haake oscillating-rotational viscosimeter.

The aim of this study was to determine selected properties of extrudates produced from potato starch with the addition of ethyl alcohol. Ethyl alcohol at 5, 10, 15, and 20% concentration was added to potato starch with moisture content of 18 and 23%; the starch was then extruded in single-screw extruder. The extrusion process was carried out in three temperature variants. The resultant extrudates were determined for color, expansion ratio, and mechanical properties. Properties of the extrudates were found to depend on parameters of the extrusion process, moisture content of the extruded sample and ethanol content. Morphological characteristics of the extrudates produced were affected by temperature of the extrusion process, i.e., increasing extrusion temperature resulted in a higher expansion ratio, a lower density, and higher saturation of white color. The extrudates produced from starch with the addition of ethanol were whiter, than those prepared without ethanol. The samples produced with ethanol addition were characterized by a higher number of air spaces and thinner walls, when compared to the those prepared from starch moistened only with water. All mechanical properties were lower in the samples prepared with the addition of ethanol, as compared to the extrudates without its addition.

The aim of this study was to determine the properties of single- and double-extruded starch. Single-extruded starch was obtained using a single screw extruder at temperatures of 50–60–70°C, 90–100–120°C and 140–150–170°C, whereas double-extruded starch was obtained after grinding each of the three single-extruded starch samples and their re-extrusion at temperatures of 90–100–120°C and 140–150–170°C. The samples were determined for solubility in water and absorption capacity at a temperature of 30 and 80°C. Flow curves of the prepared pastes were plotted. Properties of double-extruded potato starch differed from those of the single-extruded starch. The study shows that the extent and direction of these changes depended on the number of the conducted extrusion processes and on their temperatures. Each successive process of extrusion and the increase in process temperatures resulted in an increased solubility of the preparations and a decrease in their water absorption capacity. Values of the rheological properties of pastes prepared from double-extruded potato starch were lower than those of the pastes produced from single-extruded potato starch.

Gelatinization characteristics of the starch and kaolin mixtures were investigated with the Brabender viscograph at starch concentration of 40 g/l and different kaolin concentrations from 0 to 60 g/l. The properties of starch gelatinization were affected by the addition of kaolin. Above a kaolin concentration of 12 g/l had, an additional viscosity peak was seen at 73 °C. Further increase of kaolin concentration up to 60g/l led to an increase is the additional peak at 73 °C, while the value of maximum viscosity peak decreased. The rheological features of gelatinized starch and kaolin mixtures were also investigated. Dependence of shear stress on shear rate was obtained with the use of Haake RS 100 rheometer with Z 38 AL sensor. Shear rate was first increased from zero to 200 s−1 and then decreased from 200 s−1 to zero within 400 s period. Those measurements were obtained at the 20, 40, 60 and 70 °C for the mixtures containing 10 or 20 g/l of starch and for kaolin concentrations ranging from 0 to 15 g/l. The results showed the independence between final viscosity and kaolin concentration in the mixtures. Viscosity was affected only by the temperature of the measurment and the starch concentration (10 or 20 g/l). A mathematical model for the rheological behavior of gelatinized starch, was developed which contains the number and volume of macromolecule aggregates as well as the number of bonds between aggregates. According to this model, the bonds energy between the aggregates reached the value of 2–8 kJ/mol, which seemed to be close to the Van der Waals bonds energy.

Though modification of starch through acetylation is known for about 150years, it is still an object of extensive studies at various research centers worldwide. This manuscript presents an overview of literature from the last 5years concerning starch acetylation. It also describes the applied raw materials, production procedures of acetylated starch and correlations between the degree of substitution with acetyl groups and properties of the modified preparations.

The analysis of phytates in extrudates containing rye bran was done by a colorimetric method with the Wade reagent. The changes in profiles of myo-inositol phosphates indicate that, although no isomers with positive physiological functions (such as I(1,4,5)P3, I(1,2,3)P3 or I(1,3,4,5)P4) were formed, the beneficial impact of extrusion is the reduction of phytates, as compared to the raw material. The obtained snacks containing rye bran received acceptable to desirable sensory scores.

Ein Teil der Knollen wurde mit Gammastrahlen (150 Gy) bestrahlt und ein anderer Teil nicht. Alle Knollen wurden 6 Monate bei +4°C, +7°C und +13°C gelagert. Die Eigenschaften der aus den bestrahlten und gelagerten Knollen gewonnenen Starke unterscheiden sich nicht nur in den Eigenschaften der aus ungelagerten Knollen gewonnenen Starke, sondern auch in der aus unbestrahlten Knollen gewonnenen Starke. Die Grose und Richtung der Veranderungen der Starkeeigenschaften waren von der Lagerungstemperatur abhangig. The Properties of Starch Obtained from Irradiated and at Various Temperatures Stored Potato Tubers. Potato tubers were either exposed to gamma irradiation (150 Gy) or not. They were stored at temperatures of +4°C, +7°C and +13°C for six months. The properties of the starch obtained from the irradiated tubers after storage were different from the starch obtained from the tubers before storage and from the starch obtained from the tubers not exposed to gamma irradiation. Range and trends of changes in starch properties depended on the temperature of storage.

Background. The frequency of occurrence of anesthesiological complications is closely associated with the type of operation being performed and the chosen method of inducing anesthesia. The present study described complications encountered during anesthesia for various types of surgery to correct scoliosis. The characteristic features of these operations make it possible to identify some additional risk factors associated with anesthesia. A qualitative and quantitative analysis of the data on adverse events enables comparison with published reports. The goal of this study is to compare our results with those reported by other authors, and to address the question of whether or not specific problems occurring during anesthesia for surgical correction of scoliosis have an impact on the types and frequency of complications. Material and methods. We performed a retrospective analysis of the anesthesiological documentation from the period 1998-2002 for patients who underwent surgical reconstruction by the posterior approach (329 cases) or anterior approach (108 cases). The complications reported in these two groups were analyzed. Results. We found 31 complications (9.4%) in patients operated with the posterior approach, and 10 complications (9.3%) in those operated with the anterior approach. Conclusions. The frequency of complication in the study population did not differ from that in published reports. Qualitative differences depend on the type of surgical technique used.

The optical density at the wavelength from 300 to 800 nm and the rheological behavior of gelatinized starch at its concentration from 3 to 30 g/L and the medium pH from 2 to 11 were investigated. The volume concentration of the swelling associates of macromolecules or their globules increases when pH of gelatinized starch rises. An influence of the volume concentration of gelatinized starch on the dependence of the shear stress on shear rate was studied. The dynamic viscosity is proportional to the volume concentration at the gelatinized starch concentration lower than 25% and proportional to the logarithm of the volume concentration at the starch concentration greater than 25%. Proposed mathematical model takes into account an influence of the volume concentration of swelling starch globules and the concentration of glucoside links of macromolecules between the globules of macromolecules or their associates on the dynamic viscosity of gelatinized starch. This model allows to describe the experimental data obtained.

The properties of starch separated from potato tubers were studied regarding the following storage temperatures: +20 °C, +8 °C, +4 °C and 0 °C. The study included also potato tubers having been frozen, thawed and refrozen as well as potato tubers before storage. Starch separated from the stored potato tubers showed differences in chemical composition, reducing power, granularity, whiteness and viscosity as well as gelatinization temperatures in comparison with the starch separated from potato tubers before storage. Quantity and direction of the changes within starch properties depended on storage temperatures. The smallest changes in the properties were observed during potato storage at +4 °C and +8 °C. Eigenschaften der Starke aus durch unterschiedliche Temperaturen beeinflusten Kartoffelknollen. Die Eigenschaften der aus Kartoffelknollen gewonnenen Starke wurden unter Berucksichtigung der folgenden Lagerungstemperaturen untersucht: +20 °C, +8 °C, +4 °C und 0 °C. In die Untersuchung wurden auch Kartoffelknollen einbezogen, die gefroren, aufgetaut und wieder gefroren waren oder zuvor nicht gelagert waren. Die aus den gelagerten Kartoffeln gewonnene Starke zeigte Unterschiede hinsichtlich chemischer Zusammensetzung, Reduktionsvermogen, Korngrosenverteilung, Weisgehalt, Viskositat sowie Verkleisterungstemperatur im Vergleich zu der aus ungelagerten Kartoffelknollen abgetrennten Starke. Grose und Richtung der Veranderungen der Starkeeigenschaften hingen von den Lagerungstemperaturen ab. Die geringsten Veranderungen der Eigenschaften wurden bei Lagerungstemperaturen von +4 °C und +8 °C beobachtet.

Starch separated from frozen potato tubers differed from that separated from unfrozen material in the initial pasting temperature and viscosity of 7% pastes. The starch separated from frozen and thawed potato tubers was characterized by higher temperatures of pasting than starch obtained from unfrozen potato tubers. Moreover, it showed some differences in granularity, phosphorus, calcium, sodium and potassium content as well as viscosity of 7% pastes in comparison with starch obtained from unfrozen potato tubers. Die Eigenschaften der aus gefrorenen und aufgetauten Kartoffelknollen gewonnenen Starke. Die aus gefrorenen Kartoffelknollen abgetrennte Starke unterschied sich von derjenigen aus ungefrorenem Material in der Anfangs-Verkleisterungstemperatur und in der Viskositat 7%iger Kleister. Die aus gefrorenen und aufgetauten Kartoffelknollen gewonnene Starke war durch hohere Verkleisterungstemperaturen charakterisiert als sie bei der Starke aus ungefrorenen Kartoffelknollen gefunden werden. Daruber hinaus zeigte sie gewisse Unterschiede in der Korngrosenverteilung, dem Phosphor-, Calcium-, Natrium- und Kaliumgehalt sowie auch in der Viskositat 7%iger Kleister im Vergleich zu der aus ungefrorenen Kartoffelknollen gewonnenen Starke.