Effect of Microwave Treatment on Catalysis of Papain

2012 ◽  
Vol 554-556 ◽  
pp. 1237-1242
Author(s):  
Xu Cong Yu ◽  
Lin Li ◽  
Quan Yi Fu ◽  
Bing Li
Keyword(s):  
Enzyme Activity ◽  
Fluorescence Spectroscopy ◽  
Enzyme Catalysis ◽  
Ph Value ◽  
Microwave Treatment ◽  
Microwave Processing ◽  
Disodium Edta ◽  
Optimum Ph ◽  
Enzyme Molecules ◽  
Main Factor

In this article, investigation on the effect of microwave treatment on the catalysis of papain had been carried out. According to the results, the thermal effect was found to be the main factor to cause inactivation of enzyme. The kinetic parameters and the fluorescence spectroscopy implied that the microwave processing had changed the conformation of the enzyme molecules and thus affected its activity. The results also showed that the microwave treatment had not changed the optimum pH value of the enzyme catalysis, and the inactivation rate of the enzyme was inversely proportional to the concentration of the enzyme. In addition, a certain concentration of the disodium EDTA media had been found to effectively protect the enzyme activity in microwave processing.

scholarly journals Partial purification and characterization of an endo-α-N-acetylgalactosaminidase from the culture medium of Streptomyces sp. OH-11242

1992 ◽  
Vol 288 (2) ◽  
pp. 475-482 ◽  
Author(s):  
I Ishii-Karakasa ◽  
H Iwase ◽  
K Hotta ◽  
Y Tanaka ◽  
S Omura
Keyword(s):  
Enzyme Activity ◽  
Culture Medium ◽  
Gel Filtration ◽  
Partial Purification ◽  
Gastric Mucus ◽  
Purification And Characterization ◽  
Streptomyces Sp ◽  
Optimum Ph ◽  
New Type

For the purification of a new type of endo-alpha-N-acetylgalactosaminidase from the culture medium of Streptomyces sp. OH-11242 (endo-GalNAc-ase-S) [Iwase, Ishii, Ishihara, Tanaka, Omura & Hotta (1988) Biochem. Biophys. Res. Commun. 151, 422-428], a method for assaying enzyme activity was established. Using purified pig gastric mucus glycoprotein (PGM) as the substrate, oligosaccharides liberated from PGM were pyridylaminated, and the reducing terminal sugars of oligosaccharides larger than Gal beta 1-3GalNAc were analysed by h.p.1.c. The crude enzyme of endo-GalNAc-ase-S was prepared as an 80% (w/v) ammonium sulphate precipitate from the concentrated culture medium. The enzyme was partially purified by gel chromatofocusing and subsequent DEAE-Toyopearl chromatography. Endo-enzyme activity eluted around pI 4.8 on a gel chromatofocusing column and eluted with 0.19-0.25 M-NaCl on a DEAE-Toyopearl column. In the enzyme fraction obtained, no exo-glycosidases or proteases could be detected. The molecular mass of the enzyme was estimated as 105 kDa by gel filtration, and the optimum pH was 5.5. Endo-GalNAc-ase-S hydrolysed the O-glycosidic linkage between GalNAc and Ser (Thr) in 3H-labelled and unlabelled asialofetuin, liberating both the disaccharide (Gal beta 1-3GalNAc) and the tetrasaccharide [Gal beta 1-3 (Gal beta 1-4GlcNAc beta 1-6)GalNAc]. When endo-alpha-N-acetylgalactosaminidase from Alcaligenes sp. (endo-GalNac-ase-A) was incubated with 3H-labelled and unlabelled asialofetuin, only the disaccharide (Gal beta 1-3GalNAc) was liberated.

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.

β-GLUCURONIDASE OF RABBIT POLYMORPHONUCLEAR LEUCOCYTES

1950 ◽  
Vol 28e (3) ◽  
pp. 69-79 ◽  
Author(s):  
R. J. Rossiter ◽  
Esther Wong
Keyword(s):  
Enzyme Activity ◽  
Blood Plasma ◽  
Substrate Concentration ◽  
Final Concentration ◽  
White Cell ◽  
Polymorphonuclear Leucocytes ◽  
Michaelis Constant ◽  
Glucuronidase Activity ◽  
Arsanilic Acid ◽  
Optimum Ph

Rabbit polymorphonuclear leucocytes contain an enzyme capable of hydrolyzing biosynthetic phenolphthalein mono-β-glucuronide. The concentration of the enzyme in the white cell is some 2000 times the concentration of the enzyme in the blood plasma. Under the conditions of study, the β-glucuronidase activity was proportional to the concentration of the enzyme. The effect of substrate concentration on the enzyme activity was studied and the Michaelis constant, Ks, determined. The course of the reaction was linear with time for the first 12 hr. and then fell off slightly during the next 12 hr. The optimum pH of the enzyme was 4.45 in either 0.2 M acetate or 0.2 M phthalate buffer. It was not inhibited by cyanide, azide, iodoacetate, fluoride, glycine, thiourea, urethane, arsanilic acid, acetophenone, o-cresol or m-cresol, in a final concentration of 0.01 M. The possible function of β-glucuronidase in rabbit polymorphonuclear leucocytes is discussed.

scholarly journals A Comparative Study of Fe (II) Ion Adsorption onto Chemically Activated Banana Peel and Sawdust Bio-adsorbent

2018 ◽  
Vol 6 (2) ◽  
pp. 137-141
Author(s):  
Suman Lal Shrestha
Keyword(s):  
Ph Value ◽  
Banana Peel ◽  
Ion Adsorption ◽  
Ferrous Ions ◽  
Adsorption Models ◽  
Freundlich Isotherms ◽  
Adsorption Capacities ◽  
Time Period ◽  
Optimum Ph ◽  
Different Types

The adsorption capacity of ferrous ions onto bio-sorbents prepared from two different types of bio-waste of banana peel (CABP) and sawdust (CASD) treated with sulfuric acid was studied using Langmuir and Freundlich isotherms. Result shows that the optimum pH value for about 99 % Fe (II) adsorption onto the CABP and CASD was found to be 3 and 4, respectively, after 5 hours or more contact time period. Both the Langmuir and Freundlich adsorption models are fitted to remove the Fe (II) ions from aqueous solution by the bio-adsorbent of CABP and CASD. The maximum adsorption capacities for the CABP and CASD were found to be about 34 and 116 mg/g, respectively. These results showed that the CASD seems to be more effective bio-adsorbent than the CABP to remove the Fe (II) ions from drinking or/and wastewaters.Int. J. Appl. Sci. Biotechnol. Vol 6(2): 137-141 

scholarly journals Induction of dopa (3,4-dihydroxyphenylalanine) decarboxylase in blowfly integument by ecdysone. A demonstration of synthesis of the enzyme de novo

1975 ◽  
Vol 146 (1) ◽  
pp. 121-126 ◽  
Author(s):  
E G Fragoulis ◽  
C E Sekeris
Keyword(s):  
Enzyme Activity ◽  
Steroid Hormones ◽  
De Novo ◽  
Steroid Hormone ◽  
Dopa Decarboxylase ◽  
Double Labelling ◽  
Labelling Technique ◽  
Immune Precipitation ◽  
Enzyme Molecules ◽  
Stimulation Of

The activity of the enzyme dopa (3,4-dihydroxyphenylalanine) decarboxylase, present in the epidermis cells of blowfly larvae, increases during the late third instar under the influence of the steroid hormone, ecdysone. By using the double-labelling technique and immune precipitation with univalent antibody to dopa decarboxylase, we demonstrated that the increase in enzyme activity was due to a stimulation of synthesis of enzyme molecules de novo. In this respect, the action of ecdysone is similar to the action of other steroid hormones.

scholarly journals Lignolytic Enzyme Activity of Isolated Bacteria from Termite (Coptotermes Sp.) and Milkfish (Chanos chanos Forsskal, 1775) Guts

2021 ◽  
Vol 13 (1) ◽  
pp. 70-76
Author(s):  
Emi Latifah ◽  
Putri Dwi Mulyani ◽  
Yekti Asih Purwestri
Keyword(s):  
Enzyme Activity ◽  
Bacillus Licheniformis ◽  
Test Method ◽  
Chanos Chanos ◽  
Enzyme Isolation ◽  
Optimum Ph ◽  
Qualitative Test ◽  
Pseudomonas Alcaligenes ◽  
Enzyme Source ◽  
Brevibacillus Parabrevis

Bacteria BSR 2, Pseudomonas alcaligenes (BSR 3), Brevibacillus parabrevis (BSR 8), Brevibacillus sp. (BSR 9), isolated from termite gut and Bacillus licheniformis (BSA B1) isolated from milkfish gut have been known to possess celluloytic activity. However, their lignolytic ability has not been known. This study aimed to determine the lignolytic ability of bacteria isolated from termit (Coptotermes sp.) and milkfish (Chanos chanos Forsskal, 1775) guts and their enzymes characterization. The qualitative test was done through the spot test method, while quantitative assay was performed spectrophotometrically at 335 nm to calculate vanillin concentration. The isolates were grown in Lignin Mineral Medium, then the optical density (OD620) were measured every 24 hours for 5 days using spectrophotometer to determine their growth profile and the best isolation time of the lignolytic enzyme. Based on results, the best lignolytic enzyme isolation time for strains Bacillus licheniformis (BSA B1) and BSR 2 were 5 days, yielding lignolytic enzyme activity of 0.961 ± 0.168 U/mg and 2.176 ± 0.088 U/mg respectively,  while strains Pseudomonas alcaligenes (BSR 3), Brevibacillus parabrevis (BSR 8), and Brevibacillus sp. (BSR 9) were 4 days, yielding of 1.206 ± 0.045 U/mg, 1.162 ± 0.191 U/mg, and 0.896 ± 0.108 U/mg, respectively. The strain BSR 2 showed the highest lignolytic activity compared to other strains. The optimum temperature for lignolytic enzyme activity of BSR 2 was 30 ℃ and the optimum pH was 7. The lignolytic enzyme activity showed that these bacterial isolates can be a chance to be used as new alternative lignolytic enzyme source in commercial bioconversion process.

scholarly journals Pre-fermentative treatment of a model wine with aim to serve as a functional food with decreased alcohol content

2017 ◽  
Vol 63 (01) ◽  
pp. 47-53
Author(s):  
Irina Mladenoska ◽  
Verica Petkova ◽  
Tatjana Kadifkova Panovska
Keyword(s):  
Enzyme Activity ◽  
Gluconic Acid ◽  
Functional Food ◽  
Ph Value ◽  
Enzymatic Reaction ◽  
Alginate Beads ◽  
High Concentration ◽  
Ph Optimum ◽  
Enzyme Preparations ◽  
Initial Ph

The effect of substrate concentration on the enzyme activity in the reaction of glucose conversion into gluconic acid was investigated by using three different enzyme preparations in media with two different glucose concentrations. The media were simulating the conditions in the must, thus named as minimal model must, and were composed form combination of several organic acids and glucose. Those media were having initial pH of 3.5 that is a very unfavorable for glucose oxidase activity having a pH optimum at the pH value of 5.5. Among the three preparations used, the bakery additive, Alphamalt Gloxy 5080, was the most active in the medium with glucose concentration of 10 g/L, showing conversion of more than 70% for the period of 24 h, while the same enzyme preparation in the medium with 100 g/L glucose converted only about 7% of glucose. The pH value of the medium at the beginning and at the end of the enzymatic reaction was a good indicator of the enzyme activity. It seems that for the conversion of glucose in higher concentration, enzymatic preparation in high concentration should also be used. The preliminary attempt of immobilization of two preparations of glucose oxidases in alginate beads was also performed and a successful immobilization procedure for utilization in food industry was preliminarily developed. Keywords: glucose oxidases, enzymatic pretreatment, glucose, gluconic acid, model wine, functional food

scholarly journals Comparison of sorption efficiency of natural and MnO2 coated zeolite for copper removal from model solutions

2021 ◽  
Vol 900 (1) ◽  
pp. 012003
Author(s):  
M Balintova ◽  
Z Kovacova ◽  
S Demcak ◽  
Y Chernysh ◽  
N Junakova
Keyword(s):  
Heavy Metals ◽  
Removal Efficiency ◽  
Ph Value ◽  
Batch Experiments ◽  
Modified Zeolite ◽  
Optimum Ph ◽  
Removal Of Heavy Metals ◽  
Initial Ph ◽  
Correlation Factors ◽  
Maximum Removal

Abstract Removal of heavy metals from the environment is important for living beings. The present work investigates the applicability of the natural and MnO2 - coated zeolite as sorbent for the removal of copper from synthetic solutions. Batch experiments were carried out to identify the influence of initial pH and concentration in the process of adsorption. A maximum removal efficiency of Cu(II) was observed in 10 mg/L for natural (95.6%) and modified (96.4%) zeolite, where the values was almost identical, but at concentration of 500 mg/L was the removal efficiency of modified zeolite three times higher. Based on the correlation factors R2, the Langmuir isotherms better describe the decontamination process than Freundlich. The optimum pH value was set at 5.0.

A New Way to Uniform Microwave Treatment of Epoxy Glass

2015 ◽  
Vol 813 ◽  
pp. 265-272
Author(s):  
Wei Wei Du ◽  
Lyes Douadji ◽  
Fethi Benkhenafou ◽  
Hong He ◽  
Cheng Li
Keyword(s):  
Electromagnetic Waves ◽  
Microwave Treatment ◽  
Microwave Processing ◽  
Leaf Spring ◽  
Microwave Source ◽  
Electromagnetic Modelling ◽  
Dielectric Effect ◽  
Microwave Heat ◽  
Uniform Treatment ◽  
Microwave Process

This work is part of an ambitious project aiming to manufacture epoxy-glass leaf spring by microwave processing. Physical properties of final products to be manufactured, in particular the mechanical properties, are directly dependent on uniform repartition of microwave source heating during the treatment. The major problem in microwave processing, however, is attenuation of microwave source. We propose Dielectric Effect of Attenuation Inversion of the Electromagnetic Waves (DEAI) as a new way for uniform treatment of epoxy glassmicrowave energy. This solution utilizes dielectric properties of the mold to control the microwave heat source attenuation into the composite to be treated. Electromagnetic modelling of microwave process was carried out and validated by experimental results. The results show that microwave source heating attenuation can be controlled and inversed. We demonstrated uniform treatment on epoxy-glass parts ca. 100 cm long by means of compensation of microwave source attenuation.

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