scholarly journals Production of Pectinolytic Enzymes by the Yeast Wickerhanomyces anomalus Isolated from Citrus Fruits Peels

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
María A. Martos ◽  
Emilce R. Zubreski ◽  
Oscar A. Garro ◽  
Roque A. Hours
Keyword(s):  
Single Cells ◽  
Maximal Activity ◽  
Future Application ◽  
Citrus Fruits ◽  
Enzymatic Extract ◽  
Regional Interest ◽  
Pectinolytic Enzymes ◽  
Optimum Ph ◽  
Lyase Activity ◽  
Ph Range

Wickerhamomyces anomalus is pectinolytic yeast isolated from citrus fruits peels in the province of Misiones, Argentine. In the present work, enzymes produced by this yeast strain were characterized, and polygalacturonase physicochemical properties were determined in order to evaluate the application of the supernatant in the maceration of potato tissues. W. anomalus was able to produce PG in liquid medium containing glucose and citrus pectin, whose mode of action was mainly of endo type. The supernatant did not exhibit esterase or lyase activity. No others enzymes, capable of hydrolyzing cell wall polymers, such as cellulases and xylanases, were detected. PG showed maximal activity at pH 4.5 and at temperature range between 40°C and 50°C. It was stable in the pH range from 3.0 to 6.0 and up to 50°C at optimum pH. The enzymatic extract macerated potato tissues efficiently. Volume of single cells increased with the agitation speed. The results observed make the enzymatic extract produced by W. anomalus appropriate for future application in food industry, mainly for the production of fruit nectars or mashed of vegetables such as potato or cassava, of regional interest in the province of Misiones, Argentine.

scholarly journals Vitamin A and carotenoids. The enzymic conversion of β-carotene into retinal in hog intestinal mucosa

1969 ◽  
Vol 114 (4) ◽  
pp. 689-694 ◽  
Author(s):  
Noel H. Fidge ◽  
Frank Rees Smith ◽  
DeWitt S. Goodman
Keyword(s):  
Intestinal Mucosa ◽  
Gel Filtration ◽  
Maximal Activity ◽  
Enzyme Preparations ◽  
Optimum Ph ◽  
Tween 40 ◽  
Ph Range ◽  
Optimum Ph Range ◽  
Β Carotene

The conversion of β-carotene into retinal was studied in vitro with enzyme preparations from homogenates of hog intestinal mucosa. The hog mucosal enzyme was purified about 27-fold by precipitation with ammonium sulphate, chromatography on DEAE-Sephadex and gel filtration on Sephadex G-200. The reaction displayed a narrow optimum pH range (approx. 7·8–8·2). The enzyme was stimulated strongly by the addition of thiols, and was inhibited by thiol inhibitors and by the chelating agents αα′-bipyridyl and o-phenanthroline. The reaction required the addition of an appropriate detergent (or bile salt); maximal activity was obtained by addition of an appropriate combination of detergents and lipid (specifically Tween 40, sodium glycocholate and sphingomyelin). The reaction displayed Michaelis kinetics with Km1·3×10−6m and Vmax.1·1nmole of retinal formed/hr. (for 0·7mg. of enzyme protein). The properties of the hog enzyme are similar to those previously reported for a less purified rat enzyme preparation.

scholarly journals Granulicoccus phenolivorans gen. nov., sp. nov., a Gram-positive, phenol-degrading coccus isolated from phenol-degrading aerobic granules

2007 ◽  
Vol 57 (4) ◽  
pp. 730-737 ◽  
Author(s):  
Abdul Majid Maszenan ◽  
He Long Jiang ◽  
Joo-Hwa Tay ◽  
Peter Schumann ◽  
Reiner M. Kroppenstedt ◽  
...  
Keyword(s):  
Batch Reactor ◽  
Rrna Gene ◽  
Aerobic Granules ◽  
New Genus And Species ◽  
Positive Bacterium ◽  
Gram Positive ◽  
Optimum Ph ◽  
Phenolic Wastewater ◽  
Ph Range ◽  
Capsular Material

A Gram-positive bacterium, designated strain PG-02T, was isolated by serial dilution from aerobic granules obtained from a laboratory-scale sequencing batch reactor for bioremediation of phenolic wastewater. Strain PG-02T grew axenically as cocci and is an oxidase-negative and catalase-positive, non-motile facultative anaerobe. It does not reduce nitrate and grows between 15 and 37 °C, with an optimum temperature of 30 °C. The pH range for growth is between 5.0 and 8.5, with an optimum pH of 7.0. Strain PG-02T contains type A3γ peptidoglycan (ll-A2pm←Gly with alanine at position 1 of the peptide subunit). The G+C content of the DNA is 69 mol%. Menaquinone MK-9(H4) was the major isoprenoid quinone. The polar lipids included diphosphatidylglycerol and phosphatidylglycerol, while 13-methyltetradecanoic acid (i-C15 : 0) and 1,1-dimethoxy-iso-pentadecane (i-C15 : 0 DMA) were the major components in whole-cell methanolysates. PG-02T stained positively for intracellular polyphosphate granules but not poly-β-hydroxyalkanoates. It produces capsular material and possesses an autoaggregation capability. Phenotypic and 16S rRNA gene sequence analyses showed that PG-02T differed from its closest phylogenetic relatives, namely members of the suborder Propionibacterineae, which includes the genera Tessaracoccus, Microlunatus, Luteococcus, Micropruina, Propionibacterium, Propioniferax, Nocardioides, Friedmanniella and Aeromicrobium, and that it should be placed in a new genus and species as Granulicoccus phenolivorans gen. nov., sp. nov. The type strain of Granulicoccus phenolivorans is PG-02T (=ATCC BAA-1292T=DSM 17626T).

scholarly journals AmyA, an α-Amylase with β-Cyclodextrin-Forming Activity, and AmyB from the Thermoalkaliphilic Organism Anaerobranca gottschalkii: Two α-Amylases Adapted to Their Different Cellular Localizations†

2005 ◽  
Vol 71 (7) ◽  
pp. 3709-3715 ◽  
Author(s):  
Meike Ballschmiter ◽  
Martin Armbrecht ◽  
Krasimira Ivanova ◽  
Garabed Antranikian ◽  
Wolfgang Liebl
Keyword(s):  
Amino Acid ◽  
Half Life ◽  
Extracellular Enzyme ◽  
Amino Acid Sequences ◽  
Cyclodextrin Glycosyltransferase ◽  
High Similarity ◽  
Ph Optimum ◽  
Transglycosylation Activity ◽  
Optimum Ph ◽  
Ph Range

ABSTRACT Two α-amylase genes from the thermophilic alkaliphile Anaerobranca gottschalkii were cloned, and the corresponding enzymes, AmyA and AmyB, were investigated after purification of the recombinant proteins. Based on their amino acid sequences, AmyA is proposed to be a lipoprotein with extracellular localization and thus is exposed to the alkaline milieu, while AmyB apparently represents a cytoplasmic enzyme. The amino acid sequences of both enzymes bear high similarity to those of GHF13 proteins. The different cellular localizations of AmyA and AmyB are reflected in their physicochemical properties. The alkaline pH optimum (pH 8), as well as the broad pH range, of AmyA activity (more than 50% activity between pH 6 and pH 9.5) mirrors the conditions that are encountered by an extracellular enzyme exposed to the medium of A. gottschalkii, which grows between pH 6 and pH 10.5. AmyB, on the other hand, has a narrow pH range with a slightly acidic pH optimum at 6 to 6.5, which is presumably close to the pH in the cytoplasm. Also, the intracellular AmyB is less tolerant of high temperatures than the extracellular AmyA. While AmyA has a half-life of 48 h at 70°C, AmyB has a half-life of only about 10 min at that temperature, perhaps due to the lack of stabilizing constituents of the cytoplasm. AmyA and AmyB were very similar with respect to their substrate specificity profiles, clearly preferring amylose over amylopectin, pullulan, and glycogen. Both enzymes also hydrolyzed α-, β-, and γ-cyclodextrin. Very interestingly, AmyA, but not AmyB, displayed high transglycosylation activity on maltooligosaccharides and also had significant β-cyclodextrin glycosyltransferase (CGTase) activity. CGTase activity has not been reported for typical α-amylases before. The mechanism of cyclodextrin formation by AmyA is unknown.

Effect of temperature and pH on the production, activity, and stability of α-amylase from Bacillus subtilis V37

2021 ◽  
Vol 66 (1) ◽  
pp. 72-79
Author(s):  
Thuoc Doan Van ◽  
Hung Nguyen Phuc
Keyword(s):  
Enzyme Activity ◽  
Bacillus Subtilis ◽  
Animal Feed ◽  
Culture Conditions ◽  
Effect Of Temperature ◽  
Physical Parameters ◽  
Original Activity ◽  
Optimum Ph ◽  
Production Activity ◽  
Ph Range

The effect of physical parameters such as temperature and pH on the production, activity, and stability of α-amylase from Bacillus subtilis V37 was investigated. The results indicated that the optimum culture conditions for enzyme activity were pH 7.0 and 35 oC. The optimum pH and temperature for enzyme activity were 6.0 and 70 oC. The crude enzyme was found to be stable in the pH range of 5.0 to 7.0. The enzyme was stable for 1 h at a temperature from 30 to 80 oC; nearly 100% of enzyme activity remained at temperatures of 30 - 40 oC, and about 34% of original activity remained at a temperature of 80 oC. These features demonstrated that α-amylase from B. subtilis V37 can be applied in many areas such as the food, fermentation, and animal feed industries.

scholarly journals Evaluation of optimal conditions for arginase activity in streptozotocin induced diabetic rats

2012 ◽  
Vol 50 (No. 2) ◽  
pp. 69-76 ◽  
Author(s):  
M. Erisir ◽  
E. Ercel ◽  
S. Yilmaz ◽  
S. Ozan
Keyword(s):  
Maximal Activity ◽  
Diabetic Rats ◽  
Arginase Activity ◽  
Female Rats ◽  
Kinetic Properties ◽  
Ph Profile ◽  
Optimum Ph ◽  
Liver And Kidney ◽  
And Control ◽  
Assay Conditions

The assay conditions needed to achieve maximal activity of liver and kidney arginase in diabetic and non-diabetic rats were investigated and compared. The physicochemical and kinetic properties of liver arginase in diabetic and control rats were very similar, those of kidney arginase were significantly different. It was found that preincubation temperature (68&deg;C), preincubation period (20 min), optimum pH (10.1) of liver arginase and K<sub>m</sub> (3.2) for its substrate, L-arginine, did not change in diabetic and non-diabetic rats. As a consequence of diabetes, the optimum Mn<sup>2+</sup> concentration for liver arginase only changed from 1 to 2 mM. Although the preincubation temperature and period for activation of kidney arginase in control rats was unnecessary, they were found to be 56&ordm;C and 12 min in diabetic rats. The pH profile of arginase in kidney of diabetic rats was different from that of control rats. The K<sub>m</sub> value (6.7) of arginase for L-arginine in kidney is unchanged in diabetes whereas a marked decrease in V<sub>max</sub> was found. Optimum Mn<sup>2+</sup> concentration (2 mM) for kidney arginase was unchanged in diabetes. The activity of arginase in liver of diabetic animals was higher 1.5 to 1.7 times than that of controls. Diabetes caused an about 53% decrease of arginase activity in kidney of female rats, 26% in that of males. These findings may suggest an idea that encoded arginases by separate gene loci may be affected differently by the pathological and hormonal status.

scholarly journals Digestive Proteases From Fish Processing Wastes: Their Partial Characterization and Comparison

2020 ◽  
Author(s):  
Ivana Soledad Friedman ◽  
Leonel Agustín Behrens ◽  
Nair A Pereira ◽  
Edgardo Contreras ◽  
Analia Verónica Fernández-Gimenez
Keyword(s):  
Residual Activity ◽  
Fish Processing ◽  
Intestinal Enzymes ◽  
Optimum Ph ◽  
Digestive Proteinases ◽  
Wide Ph Range ◽  
Processing Wastes ◽  
Reducing Costs ◽  
Ph Range ◽  
Percophis Brasiliensis

Abstract Fish processing generates a lot of wastes which are discarded resulting in environmental problems. However, this material represents a significant source of high-value bioproducts with potential biotechnological applications. The objective of this study was to characterize and to compare specific activities of acid and alkaline proteases recovered from the viscera of Merluccius hubbsi (Mh), Percophis brasiliensis (Pb), Urophyis brasiliensis (Ub), and Cynoscion guatucupa (Cg) under different pH and temperature conditions. Stomach proteinases from four species had a higher activity at pH 2, with stability in the range of pH 2-4. Optimum pH from intestinal enzymes of Cg was 11.5, while for the crude extract of Mh, Pb, and Ub catalytic activity was registered over a wide pH range range from 7 to 11.5. Stomach proteinases from four studied species had a higher activity at 30 °C and 50 °C, with stability at 10 °C and 30 °C. Optimum temperature from intestinal enzymes of the four tested species was 50 °C with high stability at 10 °C and 30 °C. Alkaline proteinase from all species and acid proteinases from Cg was inactivated at 70ºC, while stomach enzymes of Mh, Pb, and Ub had a residual activity lower than 5% at 80 °C after 5, 10 y 20 minutes of pre-incubation, respectively. Digestive proteinases recovered in this study could be used as biocatalysts in industrial processes, reducing costs, adding value to the fishery waste, and contributing to the reduction of environmental pollution.

scholarly journals Extraction-Chromogenic System for Cobalt Based on 5-Methyl-4-(2-thiazolylazo) Resorcinol and Benzalkonium Chloride

2021 ◽  
Vol 68 (1) ◽  
pp. 37-43
Author(s):  
Danail G. Georgiev Hristov ◽  
Petya Vassileva Racheva ◽  
Galya Konstantinova Toncheva ◽  
Kiril Blazhev Gavazov
Keyword(s):  
Benzalkonium Chloride ◽  
Limit Of Detection ◽  
Ion Association ◽  
Molar Absorptivity ◽  
Sensitivity Limit ◽  
Deprotonated Form ◽  
Limit Of Quantification ◽  
Optimum Ph ◽  
Ion Associate ◽  
Ph Range

The interaction between CoII and 5-methyl-4-(2-thiazolylazo)-resorcinol (MTAR) was studied in a water-chloroform system, in the presence or absence of benzalkonium chloride (BZC) as a cationic ion-association reagent. The optimum pH, concentration of the reagents and extraction time for the extraction of Co were found. In the presence of BZC, the extracted ion-associate could be represented by the formula (BZ+)[CoIII(MTAR2–)2], where MTAR is in its deprotonated form. The following extraction-spectrophotometric characteristics were determined: absorption maximum, molar absorptivity, Sandell’s sensitivity, limit of detection, limit of quantification, constant of extraction, distribution ratio and fraction extracted. In the absence of BZC, the extraction is incomplete and occurs in a narrow pH range. The extracted chelate contains one deprotonated and one monoprotonated ligand: [CoIII(MTAR2–)(HMTAR–)].

scholarly journals Review on Pathogenic Bacteria Listeria monocytogenes, The Detection and The Sequencing Gene Methods Isolated from Meat Products

2019 ◽  
Vol 6 (2) ◽  
Author(s):  
Bhakti Etza Setiani ◽  
Yoyok Budi Pramono ◽  
Lutfi Purwitasari
Keyword(s):  
Listeria Monocytogenes ◽  
Pathogenic Bacteria ◽  
Meat Product ◽  
Meat Products ◽  
Processed Meat ◽  
Confirmation Test ◽  
Optimum Ph ◽  
Bacterium Species ◽  
Genotypic Identification ◽  
Ph Range

A study was conducted to review on pathogenic bacteria Listeria monocytogenes, the detection and the sequencing gene methods isolated from meat products, compare selected methods that detect the presence of Listeria monocytogenes in selected raw and processed meat products. Results indicate that Listeria monocytogenenes (originally named Bacterium monocytogenes) is a gram-positive, non-sporeforming, highly mobile, rod-type, and facultative anaerobic bacterium species. It can grow under temperatures between -1.5°C to 45°C and at pH range between 4.4 and 9.4, with the optimum pH of 7. Rapid methods (PCR based and VIDAS-LDUO®) detected Listeria monocytogenes faster than the conventional method. It was also gathered that Phenotypic identification and Genotypic identification are two types of confirmation test for Listeria monocytogenes. Listeria monocytogenenes can be found in raw meat and meat product because of environmental contamination, cross contamination or error process.

Production and Thermal Characterization of an Alkaline Pectin Lyase from Penicillium notatum

2015 ◽  
Vol 11 (4) ◽  
pp. 517-525 ◽  
Author(s):  
Umme Habibah Siddiqua ◽  
Haq Nawaz Bhatti ◽  
Shazia Nouren ◽  
Saima Noreen ◽  
Ismat Bibi
Keyword(s):  
Ammonium Sulphate ◽  
Thermal Inactivation ◽  
Thermal Characterization ◽  
Maximal Activity ◽  
Inhibitory Effect ◽  
Pectin Lyase ◽  
Partial Purification ◽  
Penicillium Notatum ◽  
Enhanced Production ◽  
Lyase Activity

Abstract The present study was aimed to investigate the potential of Penicillium notatum for the production of pectin lyase under solid state culture using wheat bran as substrate. Different process parameters were optimized using completely randomized design for enhanced production of the pectin lyase. P. notatum showed maximum production (1875 U/gds) of pectin lyase with substrate amount 15 g/250 ml, moisture level 60%, pH 6, incubation period 120 h at 30°C. Pectin lyase activity was further improved with the addition of maltose and ammonium sulphate as carbon and nitrogen additives (1%), respectively. Partial purification of enzyme was carried out by ammonium sulphate precipitation at 80% saturation level. The P. notatum pectin lyase showed maximal activity at 65°C and pH 8. Km and Vmax values were 0.29% and 0.487 µmol/min, respectively. Energy of activation was found to be 5.33 kJ/mol. A detailed kinetic study of thermal inactivation was carried out. The results showed that pectin lyase exhibited resistance against thermal unfolding. Effect of various metals on pectin lyase activity was also investigated. All the metals showed inhibitory effect on the enzyme activity. The present investigation revealed that pectin lyase isolated from P. notatum is thermally stable and alkaline in nature.

scholarly journals Production of Recombinant Trichoderma reesei Cellobiohydrolase II in a New Expression System Based on Wickerhamomyces anomalus

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Dennis J. Díaz-Rincón ◽  
Ivonne Duque ◽  
Erika Osorio ◽  
Alexander Rodríguez-López ◽  
Angela Espejo-Mojica ◽  
...  
Keyword(s):  
Trichoderma Reesei ◽  
Recombinant Expression ◽  
Expression System ◽  
Enzymatic Extract ◽  
Native Strain ◽  
Wickerhamomyces Anomalus ◽  
Optimum Ph ◽  
Hydrolysis Of Cellulose ◽  
Cellobiohydrolase Ii ◽  
Hydrolysis Of

Cellulase is a family of at least three groups of enzymes that participate in the sequential hydrolysis of cellulose. Recombinant expression of cellulases might allow reducing their production times and increasing the low proteins concentrations obtained with filamentous fungi. In this study, we describe the production of Trichoderma reesei cellobiohydrolase II (CBHII) in a native strain of Wickerhamomyces anomalus. Recombinant CBHII was expressed in W. anomalus 54-A reaching enzyme activity values of up to 14.5 U L−1. The enzyme extract showed optimum pH and temperature of 5.0–6.0 and 40°C, respectively. Enzyme kinetic parameters (KM of 2.73 mM and Vmax of 23.1 µM min−1) were between the ranges of values reported for other CBHII enzymes. Finally, the results showed that an enzymatic extract of W. anomalus 54-A carrying the recombinant T. reesei CBHII allows production of reducing sugars similar to that of a crude extract from cellulolytic fungi. These results show the first report on the use of W. anomalus as a host to produce recombinant proteins. In addition, recombinant T. reesei CBHII enzyme could potentially be used in the degradation of lignocellulosic residues to produce bioethanol, based on its pH and temperature activity profile.

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