scholarly journals Synthesis of Zearalenone Immunogen and Comparative Analysis of Antibody Characteristics

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Yanan Wang ◽  
Xiaofei Wang ◽  
Haitang Zhang ◽  
Jinqing Jiang ◽  
Hanna Fotina
Keyword(s):  
Active Sites ◽  
Synthesis Method ◽  
High Specificity ◽  
Diglycidyl Ether ◽  
Uv Spectra ◽  
Total Residue ◽  
Molecular Binding ◽  
Sds Page ◽  
Reaction Test ◽  
Broad Specificity

Background. This study aimed to explore the zearalenone (ZEN) immunogen synthesis method, immunogenicity, and antibody characteristics and to lay a foundation for the establishment of immunoassay methods for ZEN single residue and ZEN and its analogs total residue. Methods. Based on the molecular structure and active sites of ZEN, oxime active ester (OAE), condensation mixed anhydride (CMA), formaldehyde (FA), and 1,4-butanediol diglycidyl ether method (BDE) were designed and used for immunogen (ZEN-BSA) synthesis. The immunogens were identified by infrared (IR) and ultraviolet (UV) spectra and gel electrophoresis (SDS-PAGE) and were then used to immunize Balb/c mice to prepare ZEN polyclonal antibody (ZEN pAb). The titers and sensitivity of the ZEN pAb were determined by indirect noncompetitive ELISA (inELISA) and indirect competitive ELISA (icELISA), respectively, and its specificity was assessed by the cross-reaction test (CR). Results. ZEN-BSA was successfully synthesized, and the molecular binding ratios of ZEN to BSA were 17.2 : 1 (OAE), 14.6 : 1 (CMA), 9.7 : 1 (FA), and 8.3 : 1 (BDE), respectively. The highest inELISA titers of ZEN pAb of each group were 1 : (6.4 × 103) (OAE), 1 : (3.2 × 103) (CMA), 1 : (1.6 × 103) (FA), and 1 : (1.6 × 103) (BDE), respectively. The 50% inhibition concentrations (IC50) for ZEN by icELISA of each group were 11.67 μg/L (OAE), 16.29 μg/L (CMA), 20.92 μg/L (FA) and 24.36 μg/L (BDE), respectively. ZEN pAb from the mice immunized with ZEN-BSA (OAE) and ZEN-BSA (CMA) had class broad specificity to ZEN and its analogs. The CRs of ZEN pAb with α-ZAL, β-ZAL, α-ZOL, β-ZOL, and ZON were 36.53%, 16.98%, 64.33%, 20.16%, and 10.66%, respectively. ZEN pAb from the mice immunized with ZEN-BSA (FA) and ZEN-BSA (BDE) had high specificity for ZEN. The CRs of ZEN pAb with its analogs were all less than 1.0%. Conclusion. This study demonstrated that the preparation of the class broad-specificity antibodies of ZEN and its analogs can be achieved by immunizing animals with the immunogen ZEN-BSA prepared by the OAE method, while the preparation of highly specific antibodies can be achieved by immunizing animals with the immunogen ZEN-BSA prepared by the FA method. These findings lay the material and technical foundation for immunoassay of ZEN single residue and ZEN and its analogs total residue.

scholarly journals Competition between Metals for Binding to Methanobactin Enables Expression of Soluble Methane Monooxygenase in the Presence of Copper

2014 ◽  
Vol 81 (3) ◽  
pp. 1024-1031 ◽  
Author(s):  
Bhagyalakshmi Kalidass ◽  
Muhammad Farhan Ul-Haque ◽  
Bipin S. Baral ◽  
Alan A. DiSpirito ◽  
Jeremy D. Semrau
Keyword(s):  
Methane Monooxygenase ◽  
High Specificity ◽  
Copper Uptake ◽  
Content Type ◽  
Soluble Methane Monooxygenase ◽  
Sds Page ◽  
Genes Encoding ◽  
Key Factor ◽  
Membrane Bound

ABSTRACTIt is well known that copper is a key factor regulating expression of the two forms of methane monooxygenase found in proteobacterial methanotrophs. Of these forms, the cytoplasmic, or soluble, methane monooxygenase (sMMO) is expressed only at low copper concentrations. The membrane-bound, or particulate, methane monooxygenase (pMMO) is constitutively expressed with respect to copper, and such expression increases with increasing copper. Recent findings have shown that copper uptake is mediated by a modified polypeptide, or chalkophore, termed methanobactin. Although methanobactin has high specificity for copper, it can bind other metals, e.g., gold. Here we show that inMethylosinus trichosporiumOB3b, sMMO is expressed and active in the presence of copper if gold is also simultaneously present. Such expression appears to be due to gold binding to methanobactin produced byM. trichosporiumOB3b, thereby limiting copper uptake. Such expression and activity, however, was significantly reduced if methanobactin preloaded with copper was also added. Further, quantitative reverse transcriptase PCR (RT-qPCR) of transcripts of genes encoding polypeptides of both forms of MMO and SDS-PAGE results indicate that both sMMO and pMMO can be expressed when copper and gold are present, as gold effectively competes with copper for binding to methanobactin. Such findings suggest that under certain geochemical conditions, both forms of MMO may be expressed and activein situ. Finally, these findings also suggest strategies whereby field sites can be manipulated to enhance sMMO expression, i.e., through the addition of a metal that can compete with copper for binding to methanobactin.

scholarly journals Purification and partial characterization of a peroxidase from plant cell cultures of Cassia didymobotrya and biotransformation studies1

1998 ◽  
Vol 331 (2) ◽  
pp. 513-519 ◽  
Author(s):  
Alberto VITALI ◽  
Bruno BOTTA ◽  
Giuliano DELLE MONACHE ◽  
Sabrina ZAPPITELLI ◽  
Paola RICCIARDI ◽  
...  
Keyword(s):  
Cell Wall ◽  
Culture Medium ◽  
Gel Filtration ◽  
Cell Suspension Cultures ◽  
High Specificity ◽  
Coniferyl Alcohol ◽  
Terminal Sequence ◽  
Sds Page ◽  
Plant Peroxidases

An acidic peroxidase (EC 1.11.1.7) produced by cell suspension cultures of Cassia didymobotrya(wild senna) was purified from culture medium collected on the 29th day. The enzyme was shown to be a glycoprotein with a pI of 3.5, a molecular mass of approx. 43 kDa by SDS/PAGE and 50 kDa by gel filtration. The N-terminal sequence was very similar to those of other plant peroxidases. The peroxidase was characterized by a high specificity towards coniferyl alcohol and other natural phenolics such as guaiacol and ferulic and caffeic acids. These findings suggest that the enzyme is involved in lignification processes of the cell wall. Moreover, the enzyme was able to catalyse the oxidation of 4,3´,4´-trihydroxychalcone and 4,3´,4´-trihydroxy-3-methoxychalcone to the corresponding 3,3´-biflavanones, as mixtures of racemic and mesoforms.

scholarly journals Hierarchical H-MOR Zeolite Supported Vanadium Oxide for Dimethyl Ether Direct Oxidation

Catalysts ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 628 ◽  
Author(s):  
Wenfeng Wang ◽  
Xiujuan Gao ◽  
Ru Feng ◽  
Qi Yang ◽  
Tao Zhang ◽  
...  
Keyword(s):  
Vanadium Oxide ◽  
Pore Structure ◽  
Dimethyl Ether ◽  
Active Sites ◽  
Synthesis Method ◽  
Product Distribution ◽  
Acid Sites ◽  
Synthesis Methods ◽  
Direct Oxidation ◽  
Post Synthesis

A series of hierarchical H-MOR zeolites with different pore structure were designed and synthesized by alkaline and alkaline-acid post-synthesis methods. The catalytic performance of hierarchical H-MOR zeolite-supported vanadium oxide was investigated for dimethyl ether (DME) direct oxidation. Different pore structures apparently affect the distribution of oxidation product distribution, especially the selectivity of DMMx and CO. The formation of mesopores for 10%V2O5/deAlmm-H-MOR markedly improved the DMMx selectivity up to 78.2% from 60.0%, and more notably, CO selectivity dropped to zero compared to that of 10%V2O5/H-MOR. The hierarchical H-MOR zeolites were confirmed to be successfully prepared by the post-synthesis method. Due to the presence of mesoporous structure, the dispersion of vanadium oxide species was enhanced, which could improve the reducibility of vanadium oxide species and also make better contact with the acid sites of zeolite to exert the synergistic effect of the bifunctional active sites. More importantly, the creation of mesopores was proved to be favorable to the mass transfer of intermediate and products to avoid the occurrence of secondary reaction, which could effectively suppress the formation of by-products. This work is helpful for us to provide a novel insight to design the catalyst with suitable pore structure to effectively synthesize diesel fuel additives from DME direct oxidation.

scholarly journals Partial purification of trypsin inhibitors from Parkia seeds (Fabaceae)

Hoehnea ◽  
2014 ◽  
Vol 41 (2) ◽  
pp. 181-186 ◽  
Author(s):  
Larissa Ramos Chevreuil ◽  
José Francisco de Carvalho Gonçalves ◽  
Leonardo de Azevedo Calderon ◽  
Luiz Augusto Gomes de Souza ◽  
Silvana Cristina Pando ◽  
...  
Keyword(s):  
Serine Proteases ◽  
High Specificity ◽  
Trypsin Inhibitors ◽  
Partial Purification ◽  
Main Band ◽  
Sds Page ◽  
Kunitz Type ◽  
Sepharose 4B ◽  
Leguminous Seeds ◽  
High Inhibition

Leguminous seeds (Fabaceae) have a high content of inhibitors of which serine protease inhibitors are the most widely studied. However, there are only a few studies related to the investigation of these proteins in tree species belonging to the Amazon flora. The protein content presented in seeds of four Amazonian Leguminosae species, Parkia pendula, P. discolor, P. multijuga and P. Nitida, was extracted by using NaCl 0.15 mol L-1 and then partially fractionated by using affinity chromatography performed on a trypsin-Sepharose 4B. These inhibitors presented different affinities between trypsin and chymotrypsin serine proteases, showing a higher inhibition to trypsin compared to chymotrypsin, except for P. nitida, which showed high inhibition against both enzymes. The SDS-PAGE analysis showed that the species from Parkia genus have a main band corresponding to partially purified trypsin inhibitors. The apparent molecular mass inhibitors (approximately 13-18 kDa) and the high specificity for trypsin suggest the occurrence of Bowman-Birk and Kunitz type inhibitors.

scholarly journals Purification and characterization of three extracellular (1→3)-β-d-glucan glucohydrolases from the filamentous fungus Acremonium persicinum

1995 ◽  
Vol 308 (3) ◽  
pp. 733-741 ◽  
Author(s):  
S M Pitson ◽  
R J Seviour ◽  
B M McDougall ◽  
J R Woodward ◽  
B A Stone
Keyword(s):  
Filamentous Fungus ◽  
Gel Filtration ◽  
High Specificity ◽  
Major Product ◽  
Ph Optimum ◽  
Sds Page ◽  
Molecular Masses ◽  
Monomeric Proteins ◽  
Ph Range

Three (1-->3)-beta-D-glucanases (GNs) were isolated from the culture filtrates of the filamentous fungus Acremonium persicinum and purified by (NH4)2SO4 precipitation followed by anion-exchange and gel-filtration chromatography. Homogeneity of the purified proteins was confirmed by SDS/PAGE, isoelectric focusing and N-terminal amino acid sequencing. All three GNs (GN I, II and III) are non-glycosylated, monomeric proteins with apparent molecular masses, estimated by SDS/PAGE, of 81, 85 and 89 kDa respectively. pI values for the three enzymes are 5.3, 5.1, and 4.4 respectively. The pH optimum for GN I is 6.5, and 5.0 for GN II and III. All three purified enzymes displayed stability over the pH range 4.5-10.0. Optimum activities for GN I, II and III were recorded at 65, 55 and 60 degrees C respectively, with both GN II and III having short-term stability up to 50 degrees C and GN I up to 55 degrees C. The purified GNs have high specificity for (1-->3)-beta-linkages and hydrolysed a range of (1-->3)-beta- and (1-->3)(1-->6)-beta-D-glucans, with laminarin from Laminaria digitata being the most rapidly hydrolysed substrate of those tested. K(m) values for GN I, II, and III against L. digitata laminarin were 0.1, 0.23 and 0.22 mg/ml respectively. D-Glucono-1,5-lactone does not inhibit any of the three GNs, some metals ions are mild inhibitors, and N-bromosuccinimide and KMnO4 are strong inhibitors. All three GNs acted in an exo-hydrolytic manner, determined by the release of alpha-glucose as the initial and major product of hydrolysis of (1-->3)-beta-D-glucans, and confirmed by viscometric analysis and the inability to cleave periodate-oxidized laminarin, and may be classified as (1-->3)-beta-D-glucan glucohydrolases (EC 3.2.1.58).

scholarly journals Moderate Temperature Treatment of Gas-Phase Volatile Organic Toluene Using NiO and NiO–TiO2 Nano-catalysts: Characterization and Kinetic Behaviors

2020 ◽  
Author(s):  
Fares Almomani ◽  
Rahul R. Bhosale ◽  
Majeda Khraisheh
Keyword(s):  
Active Sites ◽  
Synthesis Method ◽  
Solution Combustion Synthesis ◽  
Reaction Rates ◽  
Temperature Treatment ◽  
Solution Combustion ◽  
Gas Streams ◽  
Toluene Concentration ◽  
Metal Ratio ◽  
Nano Catalysts

Abstract For the first time, the potential of Ni/NiO and NiO–TiO2 nano-catalysts for the oxidation of toluene under moderate temperatures was investigated. The nano-catalysts were prepared using the solution combustion synthesis method (SCSM) and the effect of the composition of nano-catalysts, the inlet toluene concentration $$([\text{C}_{7} {\text{H}}_{8}]_{in})$$ ( [ C 7 H 8 ] in ) , the relative humidity (RH), and the temperature on the percentage of toluene conversion ($$\% {\text{TN}}_{Conv.} )$$ % TN C o n v . ) were subsequently examined. Results revealed that the nano-catalysts synthesized with a low fuel-to-metal ratio produced pure NiO, which has significant catalytic activity toward the conversion of toluene. Conversely, the high fuel-to-metal ratio generated a nano-catalysts that contains a mixture of Ni/NiO or pure Ni with low activity toward the conversion of toluene. Adding NiO to TiO2 increased the surface area of the catalyst, augmented the catalyst active sites, enhanced the oxidation of toluene, and increased CO2 selectivity ($${\text{S}}_{{{\text{CO}}_{2} }}$$ S CO 2 ). NiO and NiO–TiO2 nano-catalysts exhibited higher reaction rates, significant catalyst turnover frequency, and low activation energy. The obtained results revealed that the SCSM is a promising synthesis method for producing NiO or NiO–TiO2 nano-catalysts, which can be employed successfully for the removal of toluene from gas streams. Graphic Abstract

scholarly journals Microwave Synthesis of MCM-41 and Its Application in CO2 Absorption by Nanofluids

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Shang-Yuan Cheng ◽  
You-Zhi Liu ◽  
Gui-Sheng Qi
Keyword(s):  
Microwave Synthesis ◽  
Active Sites ◽  
Synthesis Method ◽  
Average Diameter ◽  
Narrow Particle Size Distribution ◽  
Enhancement Effect ◽  
Co2 Absorption ◽  
Enhanced Absorption ◽  
Microwave Time ◽  
Mcm 41

Microwave synthesis method is a green chemical process with mild reaction conditions, fast reaction, and low energy consumption. In this work, an order mesoporous silica material MCM-41 was synthesized by microwave technology. Functionalized MCM-41 was prepared by wet impregnation with polyethyleneimine (PEI). XRD, SEM, TEM, DLS, N2 adsorption-desorption, FTIR, and TG were used to characterize the physicochemical properties of samples. Furthermore, CO2 absorption performance in water in the presence of uncalcined MCM-41 and PEI-MCM-41 nanoparticles was evaluated. In addition, the mechanisms of enhanced absorption were also elaborated. The experimental results indicated that the optimum conditions for preparation of MCM-41 were the microwave time of 15 min, microwave temperature of 100°C, and microwave power of 200 W. Under this condition, MCM-41 with narrow particle size distribution, average diameter of 50 nm, and SBET of 1210.3 m2g-1 was obtained. The enhancement effect of PEI-MCM-41 nanoparticles was more obvious than that of uncalcined MCM-41. PEI-MCM-41 as a promoter not only increased the CO2 diffusion rate but also enhanced the adsorption capacity due to the fact that it owns more active sites that may react with CO2. The CO2 absorption improvement of PEI-MCM-41 (0.1 wt%)/H2O was 25.35% higher than that of water.

scholarly journals Effect of the Gallium and Vanadium on the Dibenzothiophene Hydrodesulfurization and Naphthalene Hydrogenation Activities Using Sulfided NiMo-V2O5/Al2O3-Ga2O3

Catalysts ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 894 ◽  
Author(s):  
Esneyder Puello-Polo ◽  
Yina Pájaro ◽  
Edgar Márquez
Keyword(s):  
Elemental Analysis ◽  
Rate Constants ◽  
Active Sites ◽  
Sol Gel ◽  
Synthesis Method ◽  
Textural Properties ◽  
Elemental Mapping ◽  
Sulfided Catalysts ◽  
Nimo Catalysts ◽  
Sol Gel Synthesis

The effect of Ga and V as support-modifier and promoter of NiMoV/Al2O3-Ga2O3 catalyst on hydrogenation (HYD) and hydrodesulfurization (HDS) activities was studied. The catalysts were characterized by elemental analysis, textural properties, XRD, XPS, EDS elemental mapping and High-resolution transmission electron microscopy (HRTEM). The chemical analyses by X-ray Fluorescence (XRF) and CHNS-O elemental analysis showed results for all compounds in agreement, within experimental accuracy, according to stoichiometric values proposed to Mo/Ni = 6 and (V+Ni)/(V+Ni+Mo) = 0.35. The sol-gel synthesis method increased the surface area by incorporation of Ga3+ ions into the Al2O3 forming Ga-O-Al bonding; whereas the impregnation synthesis method leads to decrease by blocking of alumina pores, as follows NiMoV/Al-Ga(1%-I) < NiMoV/Al-Ga(1%-SG) < NiMo/Al2O3 < Al2O3-Ga2O3(1%-I) < Al2O3-Ga2O3(1%-SG) < Al2O3, propitiating Dp-BJH between 6.18 and 7.89 nm. XRD confirmed a bulk structure typical of (NH4)4[NiMo6O24H6]•5H2O and XPS the presence at the surface of Mo4+, Mo6+, NixSy, Ni2+, Ga3+ and V5+ species, respectively. The EDS elemental mapping confirmed that Ni, Mo, Al, Ga, V and S are well-distributed on Al2O3-Ga2O3(1%-SG) support. The HRTEM analysis shows that the length and stacking distribution of MoS2 crystallites varied from 5.07 to 5.94 nm and 2.74 to 3.58 with synthesis method (SG to I). The results of the characterization sulfided catalysts showed that the synthesis method via impregnation induced largest presence of gallium on the surface influencing the dispersion V5+ species, this effect improves the dispersion of the MoS2 phase and increasing the number of active sites, which correlates well with the dibenzothiophene HDS and naphthalene HYD activities. The dibenzothiophene HDS activities with overall pseudo-first-order rate constants’ values (kHDS) from 1.65 to 7.07 L/(h·mol·m2) follow the order: NiMoV-S/Al-Ga(1%-I) < NiMo-S/Al2O3 < NiMoV-S/Al-Ga(1%-SG), whereas the rate constants’ values (k) of naphthalene HYD from 0.022 to 2.23 L/(h·mol·m2) as follow: NiMoV-S/Al-Ga(1%-SG) < NiMo-S/Al2O3 < NiMoV-S/Al-Ga(1%-I). We consider that Ga and V act as structural promoters in the NiMo catalysts supported on Al2O3 that allows the largest generation of BRIM sites for HYD and CUS sites for DDS.

scholarly journals Layered Materials with Catalytic Applications: Pillared and Delaminated Zeolites from MWW Precursors

2012 ◽  
Vol 2012 ◽  
pp. 1-35 ◽  
Author(s):  
Urbano Díaz
Keyword(s):  
Surface Area ◽  
Molecular Sieves ◽  
Active Sites ◽  
External Surface ◽  
Synthesis Method ◽  
Textural Properties ◽  
Inorganic Materials ◽  
External Surface Area ◽  
Inorganic Supports ◽  
Zeolitic Materials

Delaminated and pillared zeolites are an innovative family of molecular sieves which introduced a different concept inside the synthesis of active catalysts or inorganic supports. These types of materials exhibit an elevated accessibility due to their open structure, characterized by the high external surface area without imposed restrictions controlled by the pore sizes. These open zeolites are conformed by crystalline ordered (pillared zeolites) or disordered (delaminated zeolites) individual layers, exhibiting textural properties which are favorable to carry out catalytic processes in which it is necessary to employ catalysts with completely accessible active sites. The elevated external surface area of these zeolites is profitable to generate more specific organic-inorganic materials, acting in this case as stable inorganic matrixes. The preparation of this open type-zeolites family is based on the modification of, previously synthesized, zeolitic precursors which are preexpanded to obtain the final delaminated or pillared zeolites which exhibit very different physicochemical properties compared with the starting precursors. Along this paper, the most relevant MWW-type high accessible zeolitic materials will be considered. Their nature, characteristics, and reactivity will be shown in the function of the employed synthesis method for their preparation and the postsynthesis treatments carried out, tuning their properties.

scholarly journals PC2 Ovotransferrin: Characterization and Alternative Immunotherapeutic Activity

2017 ◽  
Vol 2017 ◽  
pp. 1-11
Author(s):  
Constantin Chiurciu ◽  
Viorica Chiurciu ◽  
Mariana Oporanu ◽  
Ionel Victor Pătrașcu ◽  
Iuliana Mihai ◽  
...  
Keyword(s):  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
High Specificity ◽  
Egg White ◽  
Negative Control ◽  
Specific Pathogen Free ◽  
Immunological Activity ◽  
Sds Page ◽  
Specific Pathogen

Characterization and evaluation of immunotherapeutic potential of ovotransferrin PC2 (OTf PC2) were performed in this study. The ovoprotein was obtained from egg white from hens immunized with bacterial antigens, pathogenic for humans. For the negative control samples, OTf was extracted from eggs collected from Specific Pathogen-Free (SPF) hens and purified by affinity chromatography on Protein G-agarose column with two eluting peaks: I, representing ovalbumin, and II, ovotransferrin. The finalapo-OTf form was reached by successive precipitation with ammonium sulfate and citric acid and theholo-OTf form by saturating theapo-form with FeCl3. Multiple OTf PC2 samples were analyzed through Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) and, based on the molecular marker migration model, the ovotransferrin (76.5 kDa) and ovalbumin (45 kDa) were detected. The agglutination reaction exhibited statistically significant high specificity of the multiple OTf PC2, by reacting with the antigens used for hens’ immunization. Following ELISA, it was established that OTf PC2 from hyperimmune eggs has specificity for all antigens; the antibody titer was high, indicating that OTf PC2 possesses immunological properties similar to immunoglobulin Y (Ig Y). This study suggests that OTf PC2 immunological activity may play a crucial role in the prevention and treatment of infections resistant to antibiotics and OTf PC2 can also act as a valuable nutraceutical.

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