scholarly journals Extraction and purification of L-Asparaginase II from local isolate of Proteus vulgaris

2011 ◽  
Vol 8 (1) ◽  
pp. 509-518
Author(s):  
Baghdad Science Journal

Forty one isolates of genus Proteus were collected from 140 clinical specimens such as urine, stool, wound, burn, and ear swabs from patients of both sex. These isolates were identified to three Proteus spp. P. mirabilis, P. vulgaris and P. penneri .The ability of these bacteria to produce L-asparaginase II by using semi quantitative and quantitative methods was determined. P. vulgaris Pv.U.92 was distinguished for high level of L-asparaginase II production with specific activity 1.97 U/mg. Optimum conditions for enzyme production were determined; D medium with 0.3% of L-asparagine at pH 7.5 with temperature degree 35°C for incubation. Ultrasonication was used to destroy the P. vulgaris Pv.U.92 cells then ASNase II was extracted and purified throughout several purification steps including precipitation with (NH4)2SO4(60-80%), DEAE-cellulose ion exchanger chromatography followed by Sephacryl S-300 filtration. The specific activity was 155.6 U/ mg and the purification fold was 27.3 with 10.4% yield.

2019 ◽  
Vol 9 (04) ◽  
pp. 689-692
Author(s):  
Hayder Nasser Al-Mentafji ◽  
Mahmoud Hamid Al-Fahdawi ◽  
Albab Fawwaz Al-farras

The aim of this study was to extract peroxides enzyme from Peganum harmala seeds; peroxides was extracted by using different extraction buffer solutions, then it was purified by three steps of purification includes precipitation with ammonium sulfate in a saturation ratio of 70 %, ion exchange chromatography through DEAE-Cellulose, and gel filtration chromatography throughout Sephadex G-100, and determine the optimum condition for extraction. This was performed by controlling the type and concentration of buffer, pH of the buffer used, and the ratio of extraction. The Sodium acetate buffer with 0.2mM and pH 5.0 was found to be the best buffer for the extraction of peroxidase. By using the extraction ratio for a plant of 1:3 (W/V), the specific activity was 195 U/mg protein. These three purification steps raised the specific activity to 235U/mg protein in the precipitation step with purification fold 2.3 and enzyme recovery 69%; the specific activity was increased to 243U/mg protein in Ion exchange step with purification fold 2.4 and enzyme recovery 23%, also the specific activity doubled after gel filtration step to 447U/mg protein with purification fold 4.4 and enzyme recovery 15%.


1969 ◽  
Vol 113 (2) ◽  
pp. 235-242 ◽  
Author(s):  
D. J. H. Brock

1. The activity of phosphofructokinase in sheep liver was found to be dependent on the composition and molarity of the buffer used in extraction. Under optimum conditions a value of 4–7μmoles/min./g. wet wt. of tissue was obtained. 2. The enzyme was purified 480-fold by a combination of ammonium sulphate fractionation, heat treatment in the presence of ethanol, DEAE-cellulose chromatography and Sephadex G-200 gel filtration. The final specific activity was 18·5μmoles/min./mg. of protein. 3. The purified enzyme was inhibited by ATP and citrate, the degree of inhibition depending on the concentration of fructose 6-phosphate, magnesium chloride and ammonium sulphate, as well as on the pH. ATP and citrate inhibition was overcome by AMP and fructose 1,6-diphosphate. 4. The enzyme was also inhibited by NADH and NADPH in a manner largely independent of other components of the assay medium. AMP and fructose 1,6-diphosphate were not able to overcome this type of inhibition. 5. Octanoate was not an inhibitor of phosphofructokinase. 6. Differences between these results and those of other workers are discussed.


Author(s):  
Ni Putu Dian Permata Prasetyaningrum

Surabaya Shipping Polytechnic emphasizes on certain areas of expertise that Taruna must possess. This is the basis after graduating from shipping polytechnics, cadets must have expertise and skills. The purpose of this study was to study the effect of inquiry, discovery learning, and creativity levels on the ability to write descriptive essays on nautical and technical cadets at Surabaya Shipping Polytechnic. This type of research is research. This research uses quantitative methods using experiments. The location used in this research is Surabaya Shipping Polytechnic. The subjects in this study were the cadets of the Nautika A, Nautika B, Teknika A, and Teknika B. classes. Based on the results of the research and discussion, the following conclusions are obtained: There are those that can be solved looking for description essays in the cadets. learning discovery method. The test results show better investigation methods than the discovery of learning, There is a difference in the ability to write a description essay about cadets who have a high level of creativity with cadets who have a low level of creativity, the test results show better who have a high level of creativity, there are related with learning methods and descriptions of the ability to write essay descriptions, the test results show learning methods and creativity descriptions of the ability to write essay descriptions.


2021 ◽  
Vol 7 (3) ◽  
pp. 229
Author(s):  
Bettina Volford ◽  
Mónika Varga ◽  
András Szekeres ◽  
Alexandra Kotogán ◽  
Gábor Nagy ◽  
...  

β-Galactosidases of Mucoromycota are rarely studied, although this group of filamentous fungi is an excellent source of many industrial enzymes. In this study, 99 isolates from the genera Lichtheimia, Mortierella, Mucor, Rhizomucor, Rhizopus and Umbelopsis, were screened for their β-galactosidase activity using a chromogenic agar approach. Ten isolates from the best producers were selected, and the activity was further investigated in submerged (SmF) and solid-state (SSF) fermentation systems containing lactose and/or wheat bran substrates as enzyme production inducers. Wheat bran proved to be efficient for the enzyme production under both SmF and SSF conditions, giving maximum specific activity yields from 32 to 12,064 U/mg protein and from 783 to 22,720 U/mg protein, respectively. Oligosaccharide synthesis tests revealed the suitability of crude β-galactosidases from Lichtheimia ramosa Szeged Microbiological Collection (SZMC) 11360 and Rhizomucor pusillus SZMC 11025 to catalyze transgalactosylation reactions. In addition, the crude enzyme extracts had transfructosylation activity, resulting in the formation of fructo-oligosaccharide molecules in a sucrose-containing environment. The maximal oligosaccharide concentration varied between 0.0158 and 2.236 g/L depending on the crude enzyme and the initial material. Some oligosaccharide-enriched mixtures supported the growth of probiotics, indicating the potential of the studied enzyme extracts in future prebiotic synthesis processes.


1986 ◽  
Vol 239 (1) ◽  
pp. 155-162 ◽  
Author(s):  
M Okada ◽  
K Owada ◽  
H Nakagawa

A [phosphotyrosine]protein phosphatase (PTPPase) was purified almost to homogeneity from rat brain, with [32P]p130gag-fps, an oncogene product of Fujinami sarcoma virus, as substrate. The characteristics of the purified preparation of PTPPase were as follows: the enzyme was a monomer with a molecular mass of 23 kDa; its optimum pH was 5.0-5.5; its activity was not dependent on bivalent cations; its activity was strongly inhibited by sodium vanadate, but was not inhibited by ZnCl2, L(+)-tartrate or NaF; it catalysed the dephosphorylation of [32P]p130gag-fps, [[32P]Tyr]casein, p-nitrophenyl phosphate and L-phosphotyrosine, but did not hydrolyse [[32P]Ser]tubulin, L-phosphoserine, DL-phosphothreonine, 5′-AMP, 2′-AMP or beta-glycerophosphate significantly. During the purification, most of the PTPPase activity was recovered in distinct fractions from those of conventional low-molecular-mass acid phosphatase (APase), which was reported to be a major PTPPase [Chernoff & Li (1985) Arch. Biochem. Biophys. 240, 135-145], from DE-52 DEAE-cellulose column chromatography, and those two enzymes could be completely separated by Sephadex G-75 column chromatography. APase also showed PTPPase activity with [32P]p130gag-fps, but the specific activity was lower than that of PTPPase with molecular mass of 23 kDa, and it was not sensitive to sodium vanadate. These findings suggested that PTPPase (23 kDa) was the major and specific PTPPase in the cell.


1973 ◽  
Vol 131 (2) ◽  
pp. 287-301 ◽  
Author(s):  
M. G. Irving ◽  
J. F. Williams

Two kinetically distinct forms of pyruvate kinase (EC 2.7.1.40) were isolated from rabbit liver by using differential ammonium sulphate fractionation. The L or liver form, which is allosterically activated by fructose 1,6-diphosphate, was partially purified by DEAE-cellulose chromatography to give a maximum specific activity of 20 units/mg. The L form was allosterically activated by K+ and optimum activity was recorded with 30mm-K+, 4mm-MgADP-, with a MgADP-/ADP2- ratio of 50:1, but inhibition occurred with K+ concentrations in excess of 60mm. No inhibition occurred with either ATP or GTP when excess of Mg2+ was added to counteract chelation by these ligands. Alanine (2.5mm) caused 50% inhibition at low concentrations of phosphoenolpyruvate (0.15mm). The homotropic effector, phosphoenolpyruvate, exhibited a complex allosteric pattern (nH+2.5), and negative co-operative interactions were observed in the presence of low concentrations of this substrate. The degree of this co-operative interaction was pH-dependent, with the Hill coefficient increasing from 1.1 to 3.2 as the pH was raised from 6.5 to 8.0. Fructose 1,6-diphosphate interfered with the activation by univalent ions, markedly decreased the apparent Km for phosphoenolpyruvate from 1.2mm to 0.2mm, and transformed the phosphoenolpyruvate saturation curve into a hyperbola. Concentrations of fructose 1,6-diphosphate in excess of 0.5mm inhibited this stimulated reaction. The M or muscle-type form of the enzyme was not activated by fructose 1,6-diphosphate and gave a maximum specific activity of 0.3 unit/mg. A Michaelis–Menten response was obtained when phosphoenolpyruvate was the variable substrate (Km+0.125mm), and this form was inhibited by ATP, as well as alanine, even in the presence of excess of Mg2+.


Pharmacia ◽  
2019 ◽  
Vol 66 (4) ◽  
pp. 209-215 ◽  
Author(s):  
Nataliia Hudz ◽  
Oksana Yezerska ◽  
Mariia Shanajda ◽  
Vladimira Horčinová Sedláčková ◽  
Piotr P. Wieczorek

Polyphenols are valuable group of phytoconstituents due to their high antioxidant activity and healing properties. Antioxidant properties of sages are attributed mainly to a high level of phenolic compounds. The aim of the present study was to elaborate an analytical procedure for the evaluation of the content of secondary metabolites of the polyphenol nature in the herb of Clary Sage (Salvia sclarea L.). Four crude extracts of Salvia sclarea herb obtained with different technologies were used to develop an analytical procedure for the total phenolic content (TPC) assay by spectrophotometric method. The optimum conditions for the analysis (time of the reaction, wavelength, and reference substances) were chosen and experimentally justified (60–80 min, 760 nm, gallic acid and rutin, respectively). Under these conditions, the developed analytical procedure is robust in the indicated time and easy for performing in phytochemical or technological laboratories. The yield of TPC from the herb of Salvia sclarea was the highest in the extracts prepared by heating at a temperature of 36–46 °C and with using the ultrasonic bath. TPC was the highest in the extract in which solvent-to-herb ratio was the least (10:1) and particle size was in the range of 2–5 mm. As a result of the studies, the analytical procedure of the determination of TPC was developed and its parameters were justified. This methodology complies with the requirements for pharmaceutical analysis to ensure the reliability of results during pharmaceutical development and routine control of Salvia sclarea extracts.


2011 ◽  
Vol 5 (3) ◽  
pp. 14-21
Author(s):  
Muhamed Omar Abdulatif ◽  
Hyder H. Assmaeel ◽  
Raghad kadhim Obeid ◽  
Ayat Adnan Abbas

he Xylanase producing strain Aspergillus niger was isolated from soil on potato dextrose agar in the presence of xylan as its first substrate for primary isolation, and then grown under liquid medium fermentation in the presence of crude xylan (rice husk) to produce D-Xylanase. the optimum conditions were determined as follows: the Optimum pH for xylanase production was found pH 5.0, xylanase was induced by xylan (rice husk) 0.1% and the production was (61.221 U/ml) and nitrogen source Yeast extract recorded highest enzyme production( 89.71 U/ml), and repressed by carbon source xylose the highest enzyme production (88.69 U/ml). The optimum temperature was 40°с for xylanase production was (35.15 U/ml), the optimum period after 7 days of incubation was (52.33 U/ml) ,the optimum substrate concentration 0.1% was (45.95 U/ml), and the optimum inoculum size was 1 x 106 (spore /ml) recorded (57.19 U/ml ).


2019 ◽  
Vol 16 (31) ◽  
pp. 692-703
Author(s):  
Aline HAAS ◽  
Cleiton VAZ ◽  
Aniela Pinto KEMPKA

Peroxidases are enzymes that catalyze the oxidation of various substrates, maintaining their enzymatic activity in wide ranges of pH and temperatures. These enzymes are used in processes for the degradation of dyes and phenolic compounds. Peroxidases are present in the tissues of several plants, and the search for new sources of this enzyme is necessary. This literature review aims to compile information about the extraction and/or purification of peroxidases contained in different plant tissues, presenting extraction methods, purification processes, enzymatic activities and their increments, according to the chemical and physical processes applied. Several plant sources can be raw material to obtain these enzymes, through different forms of extraction, where the processes of comminution predominate in the presence of buffer solution. For partial purification, are used precipitation with solvents (acetone and ethanol) and salts (ammonium sulfate) and centrifugation. For purification, chromatographic processes are used, in which molecular exclusion and affinity chromatography are prominent. It is concluded that there is a wide range of possibilities for obtaining the enzyme peroxidase from plants, with variability in the enzymatic activity when different extraction methods are applied. The purification methods used provide increases in the specific activity of the peroxidases.


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