scholarly journals Optimum conditions for isoamylase production by Pseudomonas sp.

2013 ◽  
Vol 7 (1) ◽  
pp. 3-10
Author(s):  
Hameed M. Jasim ◽  
Haneen S. Abdul-Wahab
Keyword(s):  
Batch Culture ◽  
Specific Activity ◽  
Cultural Factors ◽  
Pseudomonas Sp ◽  
Production Medium ◽  
Optimum Conditions ◽  
Medium Ph ◽  
Enzyme Specific Activity ◽  
Initial Medium

Different nutritional and cultural factors were studied to determine the optimum conditions for isoamylase production by Pseudomonas sp. in a batch culture of the production medium. These factors include carbon, nitrogen and phosphate sources and their concentrations, temperature and pH. Results showed that the optimum conditions for isoamylase production by Pseudomonas sp. were achieved when the production medium was supplemented with maltose 1%, peptone 0.4%, and K2HPO4 0.4% as a carbon, nitrogen, and phosphate sources respectively, at initial medium pH 6, and incubation at 28°C for 24 hours. Under these conditions isoamylase productivity reaches the maximum, at which enzyme specific activity was 0.85 U/mg proteins.

scholarly journals Optimum conditions for Prodigiosin production by Serratia marcescens S11

2011 ◽  
Vol 5 (3) ◽  
pp. 34-40
Author(s):  
Abdulkareem Jasim ◽  
Hameed M. Jasim ◽  
Isra'a M. Dhahi
Keyword(s):  
Serratia Marcescens ◽  
Culture Medium ◽  
Casein Hydrolysate ◽  
Brain Heart Infusion ◽  
Nitrogen Sources ◽  
Optimum Conditions ◽  
Carbon And Nitrogen Sources ◽  
Carbon And Nitrogen ◽  
Phosphate Source ◽  
Initial Medium

Different nutritional and cultural factors were studied to determine the optimum conditions for prodigiosin production by Serratia marcescens S11 in a batch culture of brain-heart infusion broth medium. These factors include carbon source and its concentration, nitrogen source and its concentration, phosphate source, temperature and pH. Results showed that the optimum conditions for prodigiosin production were achieved when the production medium was supplemented with olive oil and casein hydrolysate as a carbon and nitrogen sources respectively in a concentration of 1.5% for broth, KH2PO4 as a phosphate source at initial medium pH8, and incubation at 28°C for 24 hours. Under these optimal conditions, prodigiosin activity produced by Serratia marcescens S11 in culture medium was increased from 200 U/cell before optimization to 3000 U/cell.

scholarly journals The effect of low initial medium pH on in vitro white poplar growth

2013 ◽  
pp. 67-80
Author(s):  
Branislav Kovacevic ◽  
Dragana Miladinovic ◽  
Marina Katanic ◽  
Zoran Tomovic ◽  
Sasa Pekec
Keyword(s):  
Biomass Accumulation ◽  
Dry Mass ◽  
White Poplar ◽  
Medium Ph ◽  
Shoot Height ◽  
Initial Ph ◽  
The Media ◽  
Initial Medium ◽  
Shoot Mass

The effect of low initial medium pH on shoot and root development of five white poplar (Populus alba L.) genotypes was tested. The shoot height, fresh mass of shoots per jar, dry mass of shoots per jar, number of roots, as well as the length of the longest root were measured and final pH of the media determined, after 35 days of culture in vitro. Three initial pH values of the medium were tested: 3.0, 4.0 and 5.5 as control. Agar solidification at pH 3.0 was not achieved after sterilization in autoclave, but it was successful after sterilizing in a microwave oven. The obtained results indicate that the tested genotypes are able to significantly influence the changes of media pH during culture. The effect of differences among the examined media was significant for biomass accumulation and final media pH. Generally, significantly higher values of fresh and dry shoot mass, shoot height and the longest root length were recorded on a medium with initial pH 3.0 then on a standard medium with pH 5.5.The implications of the obtained results for the improvement of in vitro propagation of white poplars are discussed.

scholarly journals DETERMINATION OF THE OPTIMUM CONDITIONS FOR UREASE INHIBITTION EXTRACTED FROM SOME LOCAL PLANTS

2021 ◽  
Vol 52 (4) ◽  
pp. 802-809
Author(s):  
Hussein & et al.
Keyword(s):  
Specific Activity ◽  
Extraction Ratio ◽  
Inhibition Activity ◽  
Sodium Acetate Buffer ◽  
Optimum Conditions ◽  
Extraction Buffer ◽  
Urease Enzyme ◽  
Local Plants ◽  
Optimum Extraction

In the current study, four types of plants commonly used namely Soybean, chickpea, bean, pea were obtained and screened for urease activity, among this plants, chickpea was chosen with maximum enzymatic activity, and it had the highest productivity of urease enzyme (1243 U/mg protein). Also sodium acetate buffer (0.2 M, pH 5.0) was chosen as a best extraction buffer with specific activity 1460 U/mg protein. The optimum extraction ratio represented by 1:8 (w:v) after 15 min, it was given 1988 U/mg protein. As well as four types of plants include garlic, red onion, green onion and cabbage were used to select the optimum plant material that inhibited urease enzyme. Cabbage was chosen, it had the highest inhibition activity of the enzyme (41%). Also tris buffer (0.2 M, pH 9) was selected as a best extraction buffer of plants inhibitor with inhibition activity 80%. The optimum extraction ratio represented by 1:8 (w:v) after 60 min, it was given 86% enzyme inhibition activity.

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
Keyword(s):  
Enzyme Production ◽  
Quantitative Methods ◽  
Specific Activity ◽  
Deae Cellulose ◽  
Ion Exchanger ◽  
Optimum Conditions ◽  
Proteus Vulgaris ◽  
Clinical Specimens ◽  
Extraction And Purification ◽  
High Level

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.

Zymographic approach to determine the intrinsic enzyme specific activity of diamine oxidase in presence of interfering enzymes

2017 ◽  
Vol 975 ◽  
pp. 78-85 ◽  
Author(s):  
Samaneh Ahmadifar ◽  
Tien Canh Le ◽  
Lucia Marcocci ◽  
Paola Pietrangeli ◽  
Mircea Alexandru Mateescu
Keyword(s):  
Diamine Oxidase ◽  
Specific Activity ◽  
Enzyme Specific Activity

Control of morphogenetic pathways in thin cell layers of tobacco by pH

1989 ◽  
Vol 67 (3) ◽  
pp. 650-654 ◽  
Author(s):  
A. Cousson ◽  
P. Toubart ◽  
K. Tran Thanh Van
Keyword(s):  
Butyric Acid ◽  
De Novo ◽  
Culture Media ◽  
Callus Formation ◽  
Medium Ph ◽  
Vegetative Buds ◽  
Cell Layers ◽  
Initial Medium ◽  
Vegetative Bud

Thin cell layer explants of tobacco were floated in vitro on the surface of liquid culture media. The initial exogenous concentrations of indolyl-3-butyric acid, and kinetin, the initial medium pH, and the explant density were varied. Various patterns of de novo and direct differentiation without any intermediate callus (flower, vegetative bud, root) as well as the absence of morphogenesis and callus formation without any subsequent organogenesis were separately controlled on 100% of the explants. On the same exogenous combination of glucose, indolyl-3-butyric acid, and kinetin, changes in initial medium pH changed the pattern of morphogenesis. For a given initial exogenous indolyl-3-butyric acid concentration, vegetative buds were obtained at either pH 6.1 or 7.8, whereas a mixture of flowers and vegetative buds was obtained at pH 6.8. Furthermore, changes in explant density changed the morphogenetic response. It is suggested that the effects of the initial medium pH and explant density on morphogenesis may be related partially to modifications of the physicochemical properties of the cell wall and (or) plasmalemma.

Immobilization of Phenol Degrader Pseudomonas sp In Repeated Batch Culture Using Bioceramic and Sponge as Support Materials

2012 ◽  
Author(s):  
Mailin Misson ◽  
Firdausi Razali
Keyword(s):  
Batch Culture ◽  
Packed Column ◽  
Tolerance Limit ◽  
Phenol Removal ◽  
Bacterial Cells ◽  
Pseudomonas Sp ◽  
Support Materials ◽  
Removal Capacity ◽  
Repeated Batch Culture ◽  
Repeated Batch

Prestasi dua jenis penyokong yang lengai iaitu bioseramik dan span untuk menyekat gerak bakteria pengurai fenol Pseudomonas sp di dalam turus terpadat telah dikaji dalam kultur kelompok berulang. Sebelum ini, kajian kami menunjukkan bahawa penyekat gerakan telah menggandakan had daya tahan mikrob terhadap kepekatan fenol dari 1000 ppm (dalam kultur ampaian) ke 2000 ppm. Pada isipadu yang sama, bioseramik berupaya memerangkap sel bakteria 1.8 kali lebih banyak daripada span. Oleh itu, ia berupaya mengurai 100% fenol yang berkepekatan 1000 ppm dalam masa 24 jam pada kadar alir suapan 2.5 ml/min, dan mengulangi prestasi yang sama dalam enam kelompok berturut–turut seterusnya. Namun demikian, sel yang terperangkap dalam span hanya berupaya mengurai 90% fenol dalam lima kelompok. Walaupun prestasinya lebih rendah, penggunaan span untuk memerangkap sel dalam skala yang besar memberikan beberapa kebaikan seperti ringan dan senang diperoleh pada harga yang lebih murah. Kata kunci: Tersekat gerak, fenol, Pseudomonas sp, bioseramik, kultur kelompok berulang The performance of two types of inert support, namely bioceramic and sponge to immobilize a locally isolated phenol degrader Pseudomonas sp. in a packed column was investigated in repeated batch culture. Prior to this, our study indicated that immobilization had doubled the tolerance limit of the cells towards phenol from 1000 ppm (in the suspended culture), to 2000 ppm. For the same volume, the bioceramic managed to trap bacterial cells 1.8 times greater than the sponge did. As a result, it was able to remove 100% of 1000 ppm 600–ml phenol fed at a rate of 2.5 ml/min within 24 hours, and the phenol removal capacity was sustained in the next six consecutive batches. Cells entrapped in sponge however, managed to remove around 90% phenol in five batches. Despite lower performance, at large scales, the use of sponge for cell entrapment offers some merits such as lightness, and easily available at cheaper cost. Key words: Immobilization, phenol, Pseudomonas sp, bioceramic, repeated batch

Comparative studies of activity and properties of ferredoxin–NADP+ reductase during cold hardening of wheat

1976 ◽  
Vol 54 (16) ◽  
pp. 1896-1902 ◽  
Author(s):  
Joseph Riov ◽  
Gregory N. Brown
Keyword(s):  
Activation Energy ◽  
Spring Wheat ◽  
Comparative Studies ◽  
Low Temperatures ◽  
Specific Activity ◽  
Cold Hardening ◽  
Heat Inactivation ◽  
Enzyme Molecule ◽  
Enzyme Specific Activity ◽  
Michaelis Constants

Activity and properties of chloroplast ferredoxin–NADP− reductase (EC 1.6.7.1) were studied during cold hardening of two varieties of wheat (Triticum aestivnm), hardy Kharkov (winter wheat) and much less hardy Rescue (spring wheat), to determine whether adaptation to low temperatures involves changes in the activity and properties of this enzyme. Specific activity of ferredoxin–NADP− reductase increased during hardening of both varieties, but the increase was much greater in the more hardy variety, Kharkov 22 MC. No changes were found in the Michaelis constants for NADPH and 2,6-dichlorophenol indophenol, activation energy values, inhibition constants for p-chloromercuriphenylsulfonate, and sensitivity toward cold and heat inactivation of the enzyme from control and cold-hardened seedlings of both varieties. The data suggest that there is a preferential synthesis of ferredoxin–NADP− reductase during hardening of wheat, but the enzyme molecule remains unchanged.

scholarly journals Mitochondrial development in liver of foetal and newborn rats

1971 ◽  
Vol 121 (2) ◽  
pp. 341-347 ◽  
Author(s):  
S. Jakovcic ◽  
J. Haddock ◽  
G. S. Getz ◽  
M. Rabinowitz ◽  
H. Swift
Keyword(s):  
Specific Activity ◽  
Liver Mitochondria ◽  
Postnatal Period ◽  
Neonatal Rat ◽  
Inner Mitochondrial Membrane ◽  
Adult Liver ◽  
Respiratory Enzymes ◽  
Respiratory Enzyme ◽  
Foetal Liver ◽  
Enzyme Specific Activity

The development of the inner mitochondrial membrane in foetal and neonatal rat liver was studied by following three parameters: (1) the activity of several respiratory enzymes in homogenates and purified mitochondria, (2) the spectrophotometric determination of cytochrome content in the mitochondria and (3) the cardiolipin content in both homogenates and purified mitochondria. Respiratory-enzyme activities of homogenates of foetal liver were one-quarter to one-twentieth of those of homogenates of adult liver, and the enzyme specific activities in purified mitochondria from foetal liver were one-half to one-eighth of those in mitochondria from adult liver. The cardiolipin content of liver homogenates increased approximately twofold during the development period, but there was no significant change in the cardiolipin content of purified mitochondria. It is concluded that cell mitochondrial content approximately doubles in the immediate postnatal period. There was no evidence for an increase in the relative amount of cristae protein in mitochondria during this period to account for increases in mitochondrial enzyme specific activity, since cardiolipin and cytochrome concentrations remained unchanged and electron micrographs revealed no differences. The cause of the lower respiratory-enzyme specific activity in foetal liver mitochondria is unclear. Qualitative differences in respiratory units in foetal and mature animals are suggested.

scholarly journals Regulation of fitness in yeast overexpressing glycolytic enzymes: parameters of growth and viability

1992 ◽  
Vol 59 (1) ◽  
pp. 35-48 ◽  
Author(s):  
R. F. Rosenzweig
Keyword(s):  
Growth Rate ◽  
Stationary Phase ◽  
Specific Activity ◽  
Current Model ◽  
Carbon Sources ◽  
Fold Increase ◽  
Culture Cell ◽  
Phase Density ◽  
Enzyme Specific Activity ◽  
High Copy Plasmid

SummaryCurrent models predict that large increases over wild-type in the activity of one enzyme will not alter an organism's fitness. This prediction is tested in Saccharomyces cerevisiae through the use of a high copy plasmid that bears one of the following: hexokinase B (HEXB), phosphoglucose isomerase (PGI), phosphofructokinase (PFKAandPFKB), or pyruvate kinase (PYK). Transformants containing these plasmids demonstrate a four to ten-fold increase in enzyme specific activity over either the parent strain or transformants containing the plasmid alone. Haploid and diploid transformants derived from independent backgrounds were grown on both fermentable and non-fermentable carbon sources and evaluated for several components of fitness. These include growth rate under non-limiting conditions, maximum stationary phase density, and viability in extended batch culture. Cell viability is not affected by overproduction of these enzymes. Growth rate and stationary phase density do not differ significantly among strains that overexpressHEXB, PGIor contain the vector alone.PFKA, Btransformants show reduced growth rate on glucose in one background only. For these loci the current model is confirmed. By contrast, when grown on glucose, yeast overexpressingPYKdemonstrate reduced growth rate and increased stationary phase density in both backgrounds. These effects are abolished in cells containing plasmids with a Tn5 disrupted copy of thePYKgene. Our results are consistent with reports that the PYK locus may exert control over the yeast cell cycle and suggest that it will be challenging to model relations between fitness and activity for multifunctional proteins.

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