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Abstract  

Cysteine was chelated with 99m/99Tc in a freeze-dried kit containing tin(II) ions, and the green 99m/99Tc-cysteine complex (complex III) was separated to study the biodistribution. The biodistribution of 99m/99Tc-cysteine complexes was performed in mice. The renal excretion patterns of rats were studied with and without the renal tubular transport inhibitor 2,4-dinitrophenol. The carrier of Tc-cysteine complex in the blood and also the radioactive compounds in the urine were studied by HPGFC and SDS-PAGE electrophoresis. The kidney was confirmed as the target organ; serum albumin functions as a carrier to transport Tc-cysteine complex to the kidney. The protein-bound Tc-cysteine complex was the primary form in excreta, and renal tubular secretion was the foremost excretory pathway.

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A lipase from the thermophilic isolate Bacillus coagulans BTS-3 was produced and purified. The enzyme was purified 40-fold to homogeneity by ammonium sulfate precipitation and DEAE-Sepharose column chromatography. Its molecular weight was 31 kDa on SDS-PAGE. The purified lipase was immobilized on silica and its binding efficiency was found to be 60%. The enzyme took 60 min to bind maximally onto the support. The pH and temperature optima of immobilized lipase were same as those of the free enzyme, i.e. 8.5 and 55ºC, respectively.  The immobilized enzyme had shown marked thermostability on the elevated temperatures of 55, 60, 65 and 70ºC. The immobilized enzyme was reused for eigth cycles as it retained almost 80% of its activity. The catalytic activity of immobilized enzyme was enhanced in n-hexane and ethanol. The immobilized enzyme when used for esterification of ethanol and propionic acid showed 96% conversion in n-hexane in 12 h at 55ºC.

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Ultracentrifugation was used as a non-destructive method to separate dough into liquid, gel, gluten, starch and bottom phases. The protein composition in the different phases was investigated for dough prepared from spring wheat (Triticum aestivum L.). The SDS-PAGE, SE-HPLC and RP-HPLC methods were used for the analysis. The wheat protein composition of the liquid and gel phases consisted of albumins, globulins and traces of gliadins and glutenins. The gluten phase contained proteins extractable with all the extraction buffers used. A similar protein composition was found in the starch and bottom phases, but in considerably lower amounts. Specific LMW glutenin subunits were identified in the gluten phase by RP-HPLC. The albumin composition differed in the gel phase compared to the gluten and bottom phases.  Differences in protein composition due to mixing methods were detected only for the albumin composition in the liquid phases.

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A new bacterial strain, capable of degrading poly(3-hydroxybutyrate) (PHB) was isolated from soil. This organism, identified as Streptoverticillium kashmirense AF1, secreted PHB depolymerases both on solid as well as in liquid mineral salt medium containing poly(3-hydroxybutyrate) as sole carbon source. The optimum production of PHB depolymerase was observed at pH 8 and 7, at 45 °C, 1% substrate concentration and in the presence of lactose as an additional carbon source. The extracellular PHB depolymerase was purified by gel permeation chromatography using Sephadex G-75. The Streptoverticillium kashmirense AF1 produced two types of PHB depolymerases having molecular weights of about 37 and 45 kDa as determined by SDS-PAGE. The difference in dry cell mass and amount of CO 2 evolved in the test and control calculated gravimetrically through Sturm test indicated the degradative capabilities of Streptoverticillium kashmirense AF1.

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Acta Phytopathologica et Entomologica Hungarica
Authors: S. Babu, R. Nandakumar, S. Sriram, R. Jaisankar, V. Shanmugam, T. Raguchander, R. Samiyappan, and P. Balasubramania

Mutants of Rhizoctonia solani were developed using UV irradiation of the mycelia of isolate RS7, which is the field isolate causing sheath blight in rice. The mutants showed reduced virulence, as compared to RS7 in detached leaf sheath and intact rice plants. All the mutants produced some toxin but in varied quantities. The amount of toxin produced by the mu­tants was positively correlated with disease development on rice plants and detached leaf sheaths. The wild isolate RS7 and mutant RSU7 pro­duced more quantity of toxic material, which in turn related to severe sheath blight symptoms. Sclerotial production on the infected rice sheath also showed significant variation among the mutants and the virulent and less virulent isolates. SDS-PAGE analysis of the mycelial proteins show­ed many proteins of different molecular weights varying among mutants and wild isolate at different stages of mycelial growth. Correlation bet­ween reduction in toxin production and disease severity is statistically significant.

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A collection of 35 accessions of the tetraploid wild wheat Aegilops geniculata Roth (MM, UU) sampled in northern Algeria was evaluated for morphological and biochemical variability. Morphological and ecological analyses based on morphological traits and bioclimatic parameters, respectively, were assessed using principal component analysis (PCA). Accessions were differentiated by width characters, namely spike’s width, and a weak relationship between morphological traits and ecological parameters was found. Polymorphism of high molecular weight (HMW) glutenin subunits was carried on by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Among accessions analyzed, 27 alleles were identified at the two loci Glu-M1 and Glu-U1: resulting in twenty-nine patterns and a nomenclature was proposed. Two alleles at the Glu-U1 locus expressed a new subunit with a slightly slower mobility than subunit 8. These results provide new information regarding the genetic variability of HMW glutenin subunits, as well as their usefulness in cultivated wheat quality improvement.

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The probiotic characteristics of Lactobacillus brevis BG18 and Lb. plantarum BG33, isolated from traditional Turkish Tulum cheese were assessed. These two bacteriocinproducer strains exhibited good probiotic characteristics such as resistance in media containing 0.3% bile salt, pepsin (3 mg mL−1), and pancreatine (1 mg mL−1) as well as acid resistance at pH 2. They were also adhered to Caco-2 epithelial cells in a manner comparable to Escherichia coli LMG3083 (ETEC) and Salmonella Typhimurium SL1344. The strains produced a heat-stable antimicrobial compound that was shown to be proteinaceous in nature, and therefore, referred to as bacteriocins. The bacteriocins were able to inhibit growth of a number grampositive bacteria such as Listeria monocytogenes, Clostridium botulinum, Staphylococcus aureus and Bacillus cereus. Tricine-SDS-PAGE of the active fraction resulted in single bands with estimated molecular masses of 2.5 kDA and 2.7 kDA for Lb. brevis BG18 and Lb. plantarum BG33 bacteriocins, respectively.

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Prolamins are alcohol-soluble fraction of cereal proteins involved in immunological response of patients with celiac disease. The aim of this study was to analyse the similar protein complex of selected varieties of cereal, pseudocereal and legume grains by comparison of protein fractions, amino acids composition and SDS-PAGE electrophoresis. The immunoreactivity was tested by Western blot and ELISA methods. ELISA analysis recognizes celiac active epitopes in wheat gliadin (which is reference protein in determination of celiac activity), and also corresponding epitopes in other grain proteins responsible for immunological response of patients with celiac disease. Estimated quantity of celiac active sequences (calculated as gliadin content) below 20 ppm was found in species of amaranth, buckwheat and millet, as well as rice, maize, chickpea and chickling vetch. Immunological reaction with polyclonal antibody was negative for all crops, except oat, maize, millet and foxtail millet.

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Acta Alimentaria
Authors: B. Csehi, E. Szerdahelyi, K. Pásztor-Huszár, B. Salamon, A. Tóth, I. Zeke, G. Jónás, and L. Friedrich

In the experiments pork loin and beef sirloin were treated by pressures of 100 to 600 MPa by 100 MPa steps for 5 min. Colour changes of samples and the changes of proteins were investigated. The latter were examined with isoelectric focusing and SDS polyacrylamide gel electrophoresis. We found that myoglobin behaved completely differently in case of the two different species. Myoglobin has mostly lost its native state at 300 MPa pressure in case of pork, but the beef myoglobin could remain native even up to 500 MPa. The treatment at 300 MPa or higher pressure values caused almost complete aggregation and denaturation in case of pork and beef proteins. The results of SDS-PAGE and the colour measurement confirmed this finding.

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Acta Alimentaria
Authors: D. Filipović, J. Kasapović, S. Pejić, A. Nićiforović, S. B. Pajović, and M. B. Radojčić

Specific composition, protein profiles and total SOD activity were analysed in full milk samples obtained from five farms of the Milk Company IMPAZ. The effects of several laboratory treatments on milk proteins SDS-PAGE profiles and the respective SOD activity were also followed. The total SOD activity was detected in all full milk samples, and its values varied between 2 and 3 U mg-1 protein. The enzyme could be partially purified, up to »5 U mg-1 protein, by ethanol extraction. The recovered SOD activity in ethanol extract was proportional to the initial full milk SOD activity. The disruption of casein micelles by Ca2+ removal was followed by a significant decrease in SOD activity to 1.24-0.18 U mg-1 protein. The loss of enzyme activity was ascribed to the changes in milk milieu induced by dissociation of casein micelles.

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