scholarly journals Effect of chemical agents, metallic salts on the stability of α-amylase, protease and comparative analyses of enzyme activity of selected salad vegetables

Food Research ◽  
2020 ◽  
Vol 4 (4) ◽  
pp. 1066-1070
Author(s):  
M.M. Rahman ◽  
U.F. Shahjadee ◽  
F. Khanam ◽  
A.Z. Rupa ◽  
M.A.K. Azad
Keyword(s):  
Enzyme Activity ◽  
Cellulase Activity ◽  
Chemical Agents ◽  
Urease Enzyme ◽  
Metallic Salts ◽  
Activity Of Enzymes ◽  
Salad Vegetables ◽  
The Stability ◽  
Red Radish ◽  
White Radish

The present investigation was conducted to analyze the activity of enzymes (protease, αamylase, cellulase and urease) of selected salad vegetables (white radish, red radish, beet, carrot, papaya, cucumber and tomato) as well as to determine the effect of chemical agents and metallic salts on the stability of enzymes. Salad vegetables are one of the cheap sources of adequate vitamins, minerals and enzymes. The protease, α-amylase and cellulase activity were highest in papaya (4.11±0.21 U/g, 1.68±0.21 U/g and 0.26±0.13 U/ g) whereas the urease activity was not detected in papaya, cucumber and tomato. The protease, α-amylase and cellulase activity of papaya were increased 24.83%, 42.26% and 57.69% than cucumber while the cellulase activity of carrot was increased 44.45% than tomato. The activity of protease and α-amylase of beet were decreased 52.44%, 33.63% while the cellulase activity of beet was increased 36.36% from radish. The toxicity indicating urease enzyme activity was not detected in papaya, tomato and cucumber but negligible in radish, beet and carrot which can be nullified. The activities of enzymes were increased in the presence of metallic salts such as Ca2+, Mg2+ and Mn2+ while Fe2+, Zn2+ and Cu2+ inhibited the enzyme's activity moderately. Results revealed that in the presence of higher concentrations of urea, EDTA and acetic acid, the activities of all the enzymes were completely inhibited.

scholarly journals Effect of metal ions and chemical agents on the activity of endoglucanase GH5 exploited from goats-rumen bacterial metagenomic DNA data

2021 ◽  
Vol 19 (3) ◽  
pp. 509-517
Author(s):  
Nguyen Khanh Hoang Viet ◽  
Ha Thi Thuy Hoa ◽  
Truong Nam Hai ◽  
Do Thi Huyen
Keyword(s):  
Enzyme Activity ◽  
Metal Ions ◽  
Specific Binding ◽  
Tween 80 ◽  
Conserved Residues ◽  
E Coli ◽  
Chemical Agents ◽  
Gene Coding ◽  
The Stability ◽  
Triton X

A gene coding for GH5 endoglucanase exploited from metagnomic DNA data of bacteria in Vietnamese goats’ rumen was modularity structure including a catalytic module, a fibronectin-3 like module and an X module. The recombinant enzyme was sucessfully expressed in E. coli and purified.  To study the effect of some metal ions and chemicals on enzyme activity, in this study, we used some tools including Swiss-Prot, ProFunc, COFACTOR for prediction of enzyme structure and ligands interaction. The obtained results indicated that the most similar structure with enzyme had two conserved residues (Asp-190 và Asp-192) linked with Mn2+ within a radius of ~ 3.5 Å from the center of ion Mn2+ and enzyme molecule contained a disulphide bond. Experimental results for essessment of the effect of some metal ions (Ca2 +, Mn2 +, Mg2+, Ni2+, K+, Co2+, Cu2+, Zn2+, Fe3+) at the final concentration of 10 mM and of six common chemicals including SDS (1%), urea (1 µM), 2-mercaptoethanol (1 µM), EDTA (1 µM), tween 80 (1mM), triton X-100 (1 µM) showed that only Mn2+ increased enzyme activity slightly at concentration of 10 mM and two times at the concentration of 40 mM Mn2+. The Mn2+ has been identified as a specific binding agent may increase the stability and activity of endoglucanase GH5.

ASSESSMENT OF GRAY FOREST SOIL ENZYMATIC ACTIVITY IN AGRICULTURAL SYSTEMS

2019 ◽  
Keyword(s):  
Enzymatic Activity ◽  
Environmental Sustainability ◽  
Hydrolytic Enzymes ◽  
Invertase Activity ◽  
Phosphorus Cycle ◽  
Soil Enzymatic Activity ◽  
Urease Enzyme ◽  
Natural Analogues ◽  
Activity Of Enzymes ◽  
The Impact

On the grey forest medium-loamy soil of Vladimir Opolye region we have studied the impact of various methods of basic cultivation and fertilizer systems on the activity of redox and hydrolytic enzymes: ure-ase (nitrogen cycle), invertase (carbon cycle), phosphatase (phosphorus cycle), and catalase, involved in the cycle of carbon in the soil. The second humus horizon with capacity of 19-24cm was found at the depth of 20 - 21 cm on the experimental field. We have studied three modes of basic soil cultivation: an-nual shallow flat plowing (6-8 cm), annual deep flat plowing (20-22 cm), and annual moldboard plowing (20-22 cm) with normal and intensive application of fertilizers. The most enzymatically active layer is 0-20 cm. No relevant difference has been found in the level of enzymes activity between variants of basic soil treatment. Activity of enzymes increases with application of fertilizers on the intensive background. In agrogenic soils, soil enzymatic activity is lower on average by 16-22% compared to the soil of the res-ervoir. The biggest negative transformation of activity has been observed at the urease enzyme (up to 50%). With annual moldboard plowing on the intensive backgroung, enzyme activity has been close to the natural level – 98.4%. Catalise and invertase activity in this case were found to be higher (105 and 116% respectively) than that of natural analogues. Activity of enzymes increases with intensive application of fertilizers as compared with normal background. This is particularly evident with 6-8cm deep beardless plowing and 20-22cm deep moldboard plowing. In general, the obtained biochemical indicators charac-terize the highest environmental sustainability of this variation within our research.

Directionality and the Role of Polarization in Electric Field Effects on Radical Stability

2017 ◽  
Vol 70 (4) ◽  
pp. 367 ◽  
Author(s):  
Ganna Gryn'ova ◽  
Michelle L. Coote
Keyword(s):  
Electric Field ◽  
External Electric Field ◽  
Radical Reactions ◽  
Electric Field Effects ◽  
Dissociation Energies ◽  
Barrier Heights ◽  
Diol Dehydratase ◽  
Group A ◽  
Activity Of Enzymes ◽  
The Stability

Accurate quantum-chemical calculations are used to analyze the effects of charges on the kinetics and thermodynamics of radical reactions, with specific attention given to the origin and directionality of the effects. Conventionally, large effects of the charges are expected to occur in systems with pronounced charge-separated resonance contributors. The nature (stabilization or destabilization) and magnitude of these effects thus depend on the orientation of the interacting multipoles. However, we show that a significant component of the stabilizing effects of the external electric field is largely independent of the orientation of external electric field (e.g. a charged functional group, a point charge, or an electrode) and occurs even in the absence of any pre-existing charge separation. This effect arises from polarization of the electron density of the molecule induced by the electric field. This polarization effect is greater for highly delocalized species such as resonance-stabilized radicals and transition states of radical reactions. We show that this effect on the stability of such species is preserved in chemical reaction energies, leading to lower bond-dissociation energies and barrier heights. Finally, our simplified modelling of the diol dehydratase-catalyzed 1,2-hydroxyl shift indicates that such stabilizing polarization is likely to contribute to the catalytic activity of enzymes.

Sinapine Esterase I. Characterization of Sinapine Esterase from Cotyledons of Raphanus sativus

1979 ◽  
Vol 34 (9-10) ◽  
pp. 715-720 ◽  
Author(s):  
Gerhild Nurmann ◽  
Dieter Strack
Keyword(s):  
Enzyme Activity ◽  
Esterase Activity ◽  
Raphanus Sativus ◽  
Sinapic Acid ◽  
Inhibitory Effect ◽  
Ph Optimum ◽  
Diisopropyl Fluorophosphate ◽  
E 600 ◽  
Red Radish

Abstract From cotyledons of Raphanus sativus (red radish) an esterase activity which catalyzes the hy­drolysis of sinapine into sinapic acid and choline has been isolated. The enzyme, which has a near absolute specificity, is not analogous with any esterase described in the literature. The reaction has a pH optimum of 8.5 and the apparent Km is 1.95 × 10-5 m. The enzyme is relatively insensi­tive to both physostigmine (eserine) {Ki = 1.73 × 10-4 m) and neostigmine (Ki = 2 .1 3 × 10-4 ᴍ). Diisopropyl fluorophosphate (DFP) showed no inhibition and diethyl p-nitrophenylphosphate (E 600) only a slight inhibitory effect at 10-5 ᴍ, respectively. Choline (10-2 ᴍ) was inhibitory but acetylcholine (10-2 ᴍ) stimulated the enzyme activity.

scholarly journals Structural and biochemical characterization of bifunctional XynA

2020 ◽  
Author(s):  
Wei Xie ◽  
Qi Yu ◽  
Yun Liu ◽  
Ruoting Cao ◽  
Ruiqing Zhang ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Enzyme Activity ◽  
Catalytic Mechanism ◽  
Biochemical Characterization ◽  
Cellulase Activity ◽  
Cost Savings ◽  
Site Directed Mutagenesis ◽  
Enzyme Activity Assay ◽  
Great Cost ◽  
Terminal Domain

AbstractXylan and cellulose are the two major constituents in numerous types of lignocellulosic biomass, representing a promising resource for biofuels and other biobased industries. The efficient degradation of lignocellulose requires the synergistic actions of cellulase and xylanase. Thus, bifunctional enzyme incorporated xylanase/cellulase activity has attracted considerable attention since it has great cost savings potential. Recently, a novel GH10 family enzyme XynA identified from Bacillus sp. is found to degrade both cellulose and xylan. To understand its molecular catalytic mechanism, here we first solve the crystal structure of XynA at 2.3 Å. XynA is characterized with a classic (α/β)8 TIM-barrel fold (GH10 domain) flanked by the flexible N-terminal domain and C-terminal domain. Circular dichroism, protein thermal shift and enzyme activity assays reveal that conserved residues Glu182 and Glu280 are both important for catalytic activities of XynA, which is verified by the crystal structure of XynA with E182A/E280A double mutant. Molecular docking studies of XynA with xylohexaose and cellohexaose as well as site-directed mutagenesis and enzyme activity assay demonstrat that Gln250 and His252 are indispensible to cellulase and bifunctional activity, separately. These results elucidate the structural and biochemical features of XynA, providing clues for further modification of XynA for industrial application.

scholarly journals EFFECT OF USING L-ASPARAGINASE IN REDUCING ACRYLAMIDE PERCENTAGE IN BISICUT

2016 ◽  
Vol 47 (4) ◽  
Author(s):  
Jebur & et al.
Keyword(s):  
High Performance Liquid Chromatography ◽  
Enzyme Activity ◽  
Liquid Chromatography ◽  
High Performance ◽  
Specific Activity ◽  
Control Sample ◽  
The Other ◽  
Enzyme Efficiency ◽  
Negative Effect ◽  
The Stability

This study was aimed to know the efficiency of partially purified L- asparaginase produced from local isolate from Erwinia spp. to reduce the percentage of acrylamide formed in Biscuit. Four types of biscuit from wheat flour were prepared (T1, T2, T3, T4),and T1 as control. High performance liquid chromatography technique was used to estimate acrylamide ratio in biscuit , Effect of enzyme addition  on flour chemical and rheological properties was studied, also dough behavior ,gluten percentage, water absorption and amylase enzyme activity was estimated. The results revealed  that  the  addition of  experimental asparaginase ( specific activity 20.5 unite mg-1 ) with 1% of flour weight lead to reduce in acrylamide formation in Biscuit  to 89 %  compared  to  control sample ( in absence of enzyme ) . Moreover, the addition of Asparagine to flour at 0.1 % of its weight, where L- asparaginase was available caused a negative effect on enzyme efficiency in reducing the acrylamide in biscuit. So the level of acrylamide was reduced to 57.7 %. In the other hand , the percentage of acryl amide in biscuit was increased to   233 % when the asparagine was added to mixture in absence of L- asparaginase .Addition of  the enzyme to flour have no effect on the percentage value of gluten but improved the  stability of dough .The  enzyme  addition also led to increase amylases activities.  Addition of experimental enzyme had no effect on quality and sensory evaluation of biscuit.

scholarly journals Stability of cellulase in ionic liquids: correlations between enzyme activity and COSMO-RS descriptors

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Jacob Nedergaard Pedersen ◽  
Bianca Pérez ◽  
Zheng Guo
Keyword(s):  
Hydrogen Bond ◽  
Enzyme Activity ◽  
Ionic Liquids ◽  
Bond Energy ◽  
Crucial Role ◽  
Enzymatic Saccharification ◽  
Cellulase Activity ◽  
Cellulose Dissolution ◽  
Ion Size ◽  
Selection Of

AbstractIonic liquids (ILs) are effective in pretreating cellulose for enhanced enzymatic saccharification, however ILs can inactivate cellulases. To guide the selection of ILs, the activity of cellulase was correlated with COSMO-RS calculations and descriptors of ILs including hydrogen bond (H-bond) basicity/acidity, polarity and ion size. Trends were deduced using an anion-series and a cation-series of ionic liquids in aqueous solutions. The activity in the cation-series was best correlated with the size of varied cations, whereas the activity in the anion-series showed a pronounced correlation to H-bond basicity and polarity of different anions. COSMO-RS was further used to predict the solubility of cellulose in ILs, which was correlated with cellulase activity on IL-pretreated cellulose. The best correlations were found between the enzyme activity in the anion-series ILs and the logarithmic activity coefficients, the H-bond energy, H-bond basicity and polarizability, underlining that the anion plays a crucial role in cellulose dissolution.

Study on the Enzyme Activity Change during the Aerobic Composting Process of Sewage Sludge

2014 ◽  
Vol 955-959 ◽  
pp. 706-710
Author(s):  
Jun Ling Niu ◽  
Jun Hui He
Keyword(s):  
Enzyme Activity ◽  
High Temperature ◽  
Sewage Sludge ◽  
Moisture Content ◽  
Cellulase Activity ◽  
Moisture Loss ◽  
Intensity Change ◽  
Composting Process ◽  
Activity Intensity ◽  
Sludge Disposal

Compost is widely used for treating urban garbage and sewage sludge. The enzyme activity is one of the important parameters of microbial quantity and its activity intensity change in the composting process, and all of the biochemical reactions during the composting process are carried out with the enzymes involving. The composting progress and the material change are directly reflected by the enzyme activity. In Zhengzhou Bagang sludge disposal plant, sludge was mixed with straw to compost together and with the technology of high temperature solid state aerobic slot for sludge treatment. This study was done to research the tendency of peroxide enzyme activity, cellulose enzyme activity, pH, conductivity, moisture content in the process of compost. The result showed that at the beginning of the compost, cellulase activity increased first and then decreased gradually and tended to be stable. The catalase activity was higher at the beginning of the compost and at the period of temperature raising it was stable basically, then decreases quickly and after that it maintain on the lower level. The moisture content declined gradually during the composting process, and in the period of high temperature there are more moisture loss. PH increased at first, and with the temperature raised to high the pH decreased gradually and tended to be stable. Conductivity increased first, then decreased gradually to steady.

scholarly journals Influence of fullerenol C60(OH)24 on enzime status in serum of rats after single dose administration of doxorubicine

2008 ◽  
Vol 62 (3) ◽  
pp. 191-196 ◽  
Author(s):  
Biljana Govedarica ◽  
Vukosava Djordjevic-Milic ◽  
Natasa Radic ◽  
Branislava Srdjenovic ◽  
Aleksandar Djordjevic
Keyword(s):  
Enzyme Activity ◽  
Single Dose ◽  
Free Radicals ◽  
Side Effects ◽  
Topoisomerase Ii ◽  
Control Group ◽  
Limiting Factor ◽  
Dose Administration ◽  
Activity Of Enzymes

The antracycline antibiotics have one of the widest areas of use in oncology. The most investigated mechanisms of their antineoplastic activity include: interactions of these antibiotics with DNA, inhibition of topoisomerase II and production of free radicals. However, the side effects of doxorubicin, especially cardiotoxicity, are the limiting factor of its use in cancer therapy. The aim of this research was to investigate the influence of fullerenol ?60(?H)24 as a cytoprotector in single doze administration of doxorubicin on the activity of enzymes in serum (CK, AST, ALT, LDH and a-HBDH) in rats in in vivo system. Activity of enzymes (CK, LDH, HBDH, AST, and ALT) in serume was measured with standard commercial methods. The results of analysis of the samples treated with the combination of fullerenol and doxorubicin show no difference in enzyme activity in comparison with the control group. The results indicate the possibility of using fullerenol as a protector in the therapy with doxorubicin in malign neoplasm.

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