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This study aimed to isolate and comprehensively characterize chitinase-producing bacterial isolates collected from diverse aquatic stations in the Red Sea. Out of twenty nine isolates, chitinase-producing marine Enterococcus hirae (OR064172) and Enterococcus faecalis (OR053873) were biochemically and genetically identified. The two isolates have primary specific activity of 10.7 and 11.5U/ mg for E. hirae and E. faecalis, respectively. To enhance the purity of the chitinase enzymes, ammonium sulfate precipitation was employed, yielding 12.9 and 13.47U/ mg for 70% fractions of E. hirae and E. faecalis, respectively. Afterward, DEAEcellulose chromatography was utilized for the purification process, resulting in two peaks for E. hirae and one peak for E. faecalis. The results of chitinase characterization indicated optimal conditions with a temperature of 37°C, a pH of 6.5, and a salt tolerance of up to 1% for both strains. The indepth kinetic chitinase analysis unveiled the optimum Km (0.03 and 0.07) and Vmax (0.124 and 0.0003) conditions for chitinase activity for both E. hirae and E. faecalis, respectively. The application of the previous strains at the economic level involves the production of chitinase using marine shrimp waste in an attempt to extract beneficial products. The solid state fermentation process of this waste for both isolates was also tested, with results indicating that the specific activity of the produced enzyme was 8.48 and 11.38U/ mg, respectively, achieving the highest production after 48 hours. This study adeptly accomplished the isolation and identification of chitinase-producing marine bacterial isolates. The rigorous purification and comprehensive characterization of chitinase enzymes offer valuable insights into their production, refinement, and utilization across diverse industries, particularly within aquaculture and waste management. [ABSTRACT FROM AUTHOR]

Arginase was purified from human serum of healthy and patient with type II Diabetes mellitus subjects. The purification steps included, DEAE-cellulose chromatography and gel filtration on Sepharoe6B.The molecular weight of native arginase was find to be (94 Kd), by gel filtration. The purified human serum arginase is characterized by optimum pH of (9.5), optimum pH of stability is between (9-10), optimum temperature (350C), temperature of stability is between (30-500C) in both healthy and patient subjects. [ABSTRACT FROM AUTHOR]

The use of a modified, four-stage purification scheme allowed us to obtain electrophoretically homogeneous preparations of constitutive forms of succinate dehydrogenase from maize (Zea mays L.) scutellum in the late stages of seed germination. It has been established that the isoenzymes differed significantly in their quaternary structure. Thus, succinate dehydrogenase 1 turned out to be a heterotetramer, and succinate dehydrogenase 2 turned out to be a heteroterodimer. It was found that their main catalytic and kinetic characteristics also differed, in particular, by their affinity to the substrate (succinate) and the value of pH optimum of the catalyzed reaction. Succinate dehydrogenase 2 was characterized by enhanced resistance to a specific inhibitor—malonate. [ABSTRACT FROM AUTHOR]

L-Asparaginase (L-asparagine amido-hydrolase, EC 3.5.1.1) is an industrially and pharmaceutically important enzyme that catalyses the hydrolysis of asparagine into aspartic acid and ammonia. In this study, L-asparaginase was produced from Fusarium sp. LCJ273. The crude L-asparaginase produced was precipitated using ammonium sulphate precipitation followed by purification using ion exchange chromatography. The molecular weight of L-asparaginase was found to be approximately 66 kDa by SDS-PAGE. The culture filtrate, ammonium sulphate precipitate and partially purified Lasparaginase exhibited optimum activity in pH 7.0 at 30°C. The partially purified L-asparaginase from Fusarium sp. LCJ273 showed 100% relative activity towards the natural substrate L-asparagine. Further, the kinetics studies of partially purified L-asparaginase revealed that Km value was 24.2 mM and Vmax value was 125 mM min-1. The in vitro anticancer activity of partially purified L-asparaginase was investigated. Different concentration of partially purified enzyme was tested on three different cell lines namely MCF-7 (breast cancer cell line), Hep-2 (human laryngeal carcinoma cells) and vero cell lines by MTT assay (3-4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide). Purified L-asparaginase reduced cell viability of MCF-7 (16.61%), Hep-2 (8.12%) and vero cell line (88.73%) after 72 hours with IC50 value of 33.21, 9.28 and 622.99 µg/mL respectively and showed better toxicity on the cell lines at a concentration of 120 µg/mL. [ABSTRACT FROM AUTHOR]

5-Hydroxy-isoxazolidinic heterocycles can be easily prepared from hydroxamic acids and suitable α,β- unsaturated aldehydes or ketones in good yields from solid state synthesis, selectively promoted by DEAE-C. The synthesized products were efficiently derivatized with representative heterobases for the preparation of nucleoside analogues suitable for biological evaluation and SAR analysis. [ABSTRACT FROM AUTHOR]

Regularities in the concentration and distribution of basic forms of phosphorus such as mineral, organic, suspended and bound to iron in complexes with humic substances were determined for diverse Karelian water bodies. Seasonal variations of the concentrations of phosphorus forms in Karelian water bodies of different trophic status were found.

We characterized polysaccharide complexes from Centaurea scabiosa L. and Centaurea pseudomaculosа Dobrocz. We proposed the technique of sequential selection of water-soluble polysaccharides and pectin substances from the aerial parts of studied objects. We have discovered that the content of water-soluble polysaccharides in the aerial parts of C. scabiosa was 2.8 times higher (2.7 ± 0.3%, n = 3) than in C. pseudomaculosа (0.97 ± 0.50%, n = 3). The content of pectin substances in the aerial parts of C. scabiosa was 2 times higher (7.6 ± 0.4%, n = 3) than in C. pseudomaculosа (3.9 ± 0.3%, n = 3). The residues of D-galacturonic acid, L-rhamnose, D-xylose, D-mannose, D-glucose, and D-galactose are the monomeric units of polysaccharide complexes from C. scabiosa and C. pseudomaculosa. Using ion-exchange chromatography, three polysaccharide fractions (molecular weights 667, 722, and 1027 kDa), whose monomer units are D-galacturonic acid, L-rhamnose, D-galactose, D-xylose, and D-glucose were isolated from the water-soluble polysaccharides of C. scabiosa. [ABSTRACT FROM AUTHOR]

This work investigates the adsorption behavior of Diethylaminoethyl-cellulose-thiourea-glutaraldehyde (DEAE-C/TU/GA) sorbent, which was synthesized through the reaction of crosslinking of glutaraldehyde using thiourea for platinum (Pt(IV)) and palladium (Pd(II)) ions from leaching solutions. The effects of pH and adsorption parameters, such as the sorbent dosage, contact time, temperature, and adsorption isotherms, were studied. Furthermore, chemical adsorption kinetic studies for adsorptions of these metal ions were carried out. The adsorption equilibrium data were fit better using the Langmuir model than the Freundlich model. The activation energies (Ea) of Pt(IV) and Pd(II) were 77.70 and 23.03 kJ/mol, respectively. The best desorption reagent was 1.0 M HCl–1.0 M TU solution for both Pd(II) and Pt(IV), which could remove more than 85% of the Pt(IV) and Pd(II) in the fourth adsorption–desorption cycle. [ABSTRACT FROM PUBLISHER]

Chemical characteristics of dissolved organic matter (DOM) extracted from an ombrotrophic bog in northern Minnesota by two methods – XAD-8 and DEAE-cellulose – were compared using 13 C NMR spectroscopy, excitation–emission matrix fluorescence spectroscopy (EEMS), and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). DOM extracted with XAD-8, a relatively hydrophobic sorbent, had a larger 13 C NMR signal in the aromatic carbon region, but DOM extracted by DEAE-cellulose, a weak anion exchanger, had a larger signal in the carboxylic carbon region. DOM extracts prepared by the two methods were similar in their overall chemical characteristics that serve as proxies for organic matter sources. For example, only small differences were observed in the fluorescence index (FI) values of the extracts, and all values were within the range expected for terrestrially-derived DOM. EEMS spectra of both extracts had “humic-like” peak A areas smaller than that of standard reference Suwannee River fulvic acid. Of 2801 distinct chemical formulas assigned during FT-ICR MS analysis of the two extracts, 66% were present in both; 15% were unique to the XAD-8 extract, and 19% were unique to the DEAE-cellulose extract. Van Krevelen plots showed that the DEAE-cellulose extract had more tannin-like and condensed aromatic entities and formulas with higher O/C ratios, whereas the XAD-8 extract had more lignin-like material and formulas with higher H/C ratios. Overall, differences in chemical characteristics of the extracts reflect the mechanisms by which the extractants operate. [ABSTRACT FROM AUTHOR]

Highlights: [•] Using Box–Behnken technique, wheat α-amylase was optimally immobilized onto DEAE-cellulose. [•] This immobilization resulted from combination of covalent attachment and ionic adsorption. [•] The immobilized enzyme showed better thermostability and storage stability over free enzyme. [Copyright &y& Elsevier]

An antifungal protein with a molecular mass of 14.3 kDa was isolated from the seeds of butterfly pea ( Clitoria ternatea) and designated as Ct protein. The antifungal protein was purified using different methods including ammonium sulphate precipitation, ion exchange chromatography on DEAE-cellulose and gel filtration on Sephadex G-50 column. Ct protein formed a single colourless rod-shaped crystal by hanging drop method after 7 days of sample loading. The protein showed lytic activity against Micrococcus luteus and broad-spectrum, fungicidal activity, particularly against the most clinically relevant yeasts, such as Cryptococcus neoformans, Cryptococcus albidus, Cryptococcus laurentii, Candida albicans and Candida parapsilosis. It also exerted an inhibitory activity on mycelial growth in several mould species including Curvularia sp., Alternaria sp., Cladosporium sp., Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Rhizopus sp., and Sclerotium sp. The present study adds to the literature on novel seed proteins with antifungal activity. [ABSTRACT FROM AUTHOR]

β-D-fructofuranosidase, (Ec 3.2.1.26) was immobilized on DEAE-cellulose, polyacrylamide and hen-egg white. storage at 4°C for 5 months indicated that the polyacrylamide and DEAE-cellulose preparations were more stable. The effect of lyophilization on immobilized invertase activity was also studied. It was found that lyophilization of the enzyme attached to DEAE-cellulose caused a decrease in its activity as compared to the other two enzymes. All lyophilized preparations could be stored for 4-5 months with a slight decrease in their activities. Batch processes were used to trace the activity of immobilized invertase. The results showed that the enzyme preparations could be re-used for eight cycles with slight effect on their activities. The inversion degree of sucrose at different concentrations and low rates using the polyacrylamide-enzyme gel ranged between 52 to 99%. A polyacrylamide-invertase gel was operated continuously for 5 days with a very low decrease in its retained activity (3%). After storage for one month the polyacrylamide-enzyme matrix conserves 83% of its initial velocity. [ABSTRACT FROM AUTHOR]

Abstract: The present work investigates gold recovery using DEAE-cellulose, a common biopolymer derivative, from synthetically prepared diluted gold-bearing solutions of 50 ppm. The effects of different recovery parameters on gold recovery efficiency were studied in detail. It was demonstrated that gold recovery efficiency increased with an increasing amount of sorbent, as well as increasing contact time. A gold recovery efficiency of 99% was attained under conditions of 20–40 g DEAE-cellulose per liter at a shaking rate of 130 rpm for 30 min at room temperature. On the other hand, with smaller amounts of sorbent (6 g/l), it was also possible to recover gold from the solution with 99% efficiency when the reaction temperature was increased to 60 °C. The shaking rate and temperature were demonstrated to play a vital role in the recovery process. It was also found that gold recovery by DEAE-cellulose is an intermediate-controlled process with an activation energy of 37.11 kJ/mol. The XRD pattern and SEM images revealed that the recovered gold was in the metallic form. [Copyright &y& Elsevier]

Binding of heparin to DEAE-cellulose membranes may reduce bioavailable heparin, thus increasing the amount of heparin needed for anticoagulation during dialysis. To test this hypothesis, blood loss and coagulation were evaluated during dialysis with DEAE-cellulose and polysulphone membranes. The heparin dose required to effect a given increase in the baseline recalcified activated clotting time (RACT) was determined using a pharmacokinetic model. Blood remaining in the dialyser post-dialysis (RBV) was measured by red cell lysis and haemoglobinometry. Plasma thrombin-antithrombin III complex (TAT) was used to assess activation of the coagulation system. RBV and changes in TAT were determined in two crossover studies. Firstly, DEAE-cellulose membranes were used at doses of heparin calculated to increase baseline RACT by 12.5% and 25%. Secondly, DEAE-cellulose and polysulphone membranes were compared at a heparin dose calculated to increase baseline RACT by 15%. RBV for DEAE-cellulose membranes was independent of the dose of heparin and did not differ from that found for polysulphone membranes. TAT concentrations increased during dialysis; however, there was no difference between the two membranes. These results show that DEAE-cellulose membranes do not require increased heparin to avoid dialyser-associated blood loss. [ABSTRACT FROM PUBLISHER]

Se purifica la proteína banda 3 a partir de membranas de eritrocitos humanos con rapidez y eficiencia, mediante una combinación de cromatografía de intercambio iónico en DEAE-celulosa y de afinidad mediante el empleo de una columna pCMB-Sepharose. La obtención de banda 3 permitirá investigar su posible participación en los fenómenos oclusivos en la drepanocitosisThe band 3 protein is purified starting form the membranes of human erythrocytes with celerity and efficiency by a combination of DEAE-cellulose ion-exchange and affinity chromatography by using a pCMB-Sepharose column. The obtention of band 3 will allow to investigate its possible participation in the occlusive phenomena in drepanocytosis

Abstract: Cryopreservation is a method of keeping parasites alive in a laboratory. However, this technique may also damage the parasite. Alternatively, parasites may be maintained by in vitro culture. Unfortunately, for Trypanosoma evansi no effective medium that is able to maintain the parasite for more than 4months has been described. In this study, we examined the effect of purifying trypomastigote through DEAE-cellulose chromatography before and after cryopreservation, by analyzing the pre-patent period, longevity, parasitemia, and count of viable parasites. Our results showed a three-times increase in the concentration of viable trypomastigote in DEAE-purified cryopreserved parasites as compared to non-DEAE-purified cryopreserved parasites. This indicates that DEAE-cellulose chromatography followed by cryopreservation is an effective method for the storage and preservation of T. evansi, with the advantage that the stocked parasites will be ready to use in molecular biology procedures. [Copyright &y& Elsevier]

A procedure for the isolation of lipase (glycerolester hydrolase, EC 3.1.1.3) from rat pancreas is described. The purification scheme includes homogenization of the pancreas. centrifugation at 3,000 rpm, centrifugation at 40,000 rpm. DEAE-cellulose chromatography, precipitation of amylase as the amylase-glycogen complex, gel filtration of the amylase-free proteins on Sephadex G-100, and chromatography on carboxymethyl-Sephadex C-50. The enzyme showed only one band on polyacrylamide gel electrophoresis and had a specific activity of 5330 ± 80 units/mg of protein.

Abstract: Objective: To investigate the potent and specific anticoagulant activity of molluscan glycosaminoglycans (GAGs) isolated from whole clam tissue Donax cuneatus (D. cuneatus). Methods: Purification of few milligram quantities of GAGs from this tissue sample permitted a thorough examination of its anticoagulant activity characterization, which was partially purified by fractionation by anion exchange chromatography using DEAE cellulose column. The isolated crude and partially purified fractionated sample was showing metachromatic shift while using azure-A. The sample also exhibited prominent of biological and anti-fXa anticoagulant activity assays. Mobility was analyzed by two different buffer systems using agarose gel electrophoresis. Results: The fractionated molluscan GAG was also found to have similar peaks as that of standard heparin when assessed by the FT-IR spectrum. Finally molecular weight was determined by the gradient PAGE for crude and fractionated-II GAG, which were found to be 65 000 Da and 50 000 Da, respectively. Conclusions: The bivalve GAG was subjected to fractionation for further purification and its chemical components were analyzed. The fractionated clam heparin also showed substantial in vitro anticoagulant activity than that of commercial heparins. [Copyright &y& Elsevier]