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1.
Sci Rep ; 14(1): 10389, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710718

RESUMO

It is believed that antivenoms play a crucial role in neutralizing venoms. However, uncontrolled clinical effects appear in patients stung by scorpions after the injection of antivenom. In this research, non-neutralized components of the venom of the Iranian scorpion Odonthobuthus doriae were analyzed after interacting with the commercial antivenom available in the market. The venom and antivenom interaction was performed, then centrifuged, and the supernatant was analyzed by high-performance liquid chromatography (HPLC). Two peaks of Odonthobuthus doriae venom were observed in the chromatogram of the supernatant. Two components were isolated by HPLC and analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) instruments. Peptide sequencing was done by Liquid Chromatography Quadrupole Time-of-Flight Tandem Mass Spectrometry (LC-Q-TOF MS/MS). Results indicate that the components of scorpion venom mainly have a molecular weight below 10 kDa, consisting of toxic peptides that disrupt the function of sodium and potassium channels. The MALDI-TOF MS results show that two toxic peptides with molecular masses of 6941 Da and 6396 Da were not neutralized by the antivenom. According to the MS/MS sequencing data, the components have been related to peptides A0A5P8U2Q6_MESEU and A0A0U4FP89_ODODO, which belong to the sodium and potassium channels toxins family, respectively.


Assuntos
Antivenenos , Venenos de Escorpião , Escorpiões , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Venenos de Escorpião/química , Antivenenos/química , Animais , Escorpiões/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem/métodos , Peptídeos/química , Sequência de Aminoácidos
2.
Inorg Chem ; 63(13): 5805-5820, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38511836

RESUMO

The use of click chemistry as a smart and suitable method for the development of new heterogeneous catalysts is based on metal-organic frameworks as well as the production of organic compounds. The development of the click chemistry method can provide a new strategy to achieve superior properties of MOFs. Here, the two metals Co and Fe are used to create a bimetallic-organic framework. In the following, the click chemistry and postmodification method are well organized and an acidic heterogeneous porous catalyst is developed. This prepared catalyst was used as a highly efficient catalyst for the preparation of new spiro-oxindoles obtained through click chemistry with good to excellent yields (80-94%). This presented catalytic system can compete with the best reported catalytic systems. The findings showed that the presence of Co and Fe metals in the MOF, and the presence of the triazole ring on the catalyst, can increase the catalytic efficiencies. This study offers novel insights into the architecture of Metal-Organic Frameworks (MOFs), click chemistry, and biologically active compounds. Additionally, the research explores the antibacterial properties of the synthesized spiro-oxindoles and catalysts. The findings reveal significant antibacterial activities of the synthesized compounds against S. aureus, MRSA, and E. coli bacteria.


Assuntos
Escherichia coli , Estruturas Metalorgânicas , Espiro-Oxindóis , Staphylococcus aureus , Antibacterianos/farmacologia
3.
Sci Rep ; 13(1): 9388, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37296128

RESUMO

In this research article, Zr-MOFs based copper complex as a novel heterogeneous and porous catalyst was designed and prepared. The structure of catalyst has verified by various techniques such as FT-IR, XRD, SEM, N2 adsorption-desorption isotherms (BET), EDS, SEM-elemental mapping, TG and DTG analysis. UiO-66-NH2/TCT/2-amino-Py@Cu(OAc)2 was used as an efficient catalyst in the synthesis of pyrazolo[3,4-b]pyridine-5-carbonitrile derivatives. The aromatization of titled molecules is performed via a cooperative vinylogous anomeric-based oxidation both under air and inert atmospheres. The unique properties of the presented method are short reaction time, high yield, reusability of catalyst, synthesis of desired product under mild and green condition.


Assuntos
Cobre , Piridinas , Espectroscopia de Infravermelho com Transformada de Fourier , Oxirredução , Adsorção
4.
Int J Biol Macromol ; 109: 443-447, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29274421

RESUMO

A novel method of laccase immobilization on epoxy-functionalized silica particles was developed. Laccase from Myceliophthora thermophila was covalently immobilized onto epoxy-functionalized matrix by nucleophilic attack of amino groups of laccase to epoxy groups of the support. The enzyme loading on the support was about 30 mg/g under the optimum conditions (pH 4.5, 24 h). The effect of pH, temperature and organic solvent on immobilized enzyme activity was determined and compared with those of free enzyme. In general the immobilized enzyme was found to be stabilized compared to the free enzyme. Lineweaver-Burk plots were used to calculate kinetic parameters for ABTS oxidation. KM values were 24.0 and 25.3 µM while vmax values were 10.0 and 1.6 µM min-1 for free and immobilized laccase, respectively. The performance of the biocatalyst was evaluated by the degradation of phenolic compounds including phenol, p-chlorophenol and catechol. The removal efficiency of catechol by immobilized laccase was about 95% after 2 h.


Assuntos
Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Compostos de Epóxi/química , Lacase/química , Lacase/metabolismo , Fenóis/metabolismo , Dióxido de Silício/química , Ascomicetos/enzimologia , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Cinética , Solventes/química , Temperatura , Água/química
5.
Nat Prod Res ; 26(13): 1229-33, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22053735

RESUMO

The chemical composition of the essential oil of Haussknechtia elymaitica Boiss. was investigated by capillary GC and GC/MS for the first time. Twelve components were identified which accounting for 99.7% of the oil composition. The major compounds were trans-asarone (59.9%), trans-methyl isoeugenol (22.4%), α-zingiberene (7.96%), ß-sesquiphellandrene (4.7%) and ß-bisabolene (4.3%). The first three compounds considered as the main components of the essential oil were isolated and characterised by spectroscopic techniques.


Assuntos
Anisóis/química , Apiaceae/química , Óleos Voláteis/química , Derivados de Alilbenzenos , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Sesquiterpenos Monocíclicos , Sesquiterpenos/química
6.
Nat Prod Res ; 26(7): 648-53, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21848491

RESUMO

From the chloroform extract of the aerial parts of Salvia xanthocheila, one new triterpene, together with two known diterpenes, two known flavonoids and a phytosterol was isolated. On the basis of comprehensive spectroscopic analyses, including electron ionisation mass spectra, ¹H-NMR, ¹³C-NMR, 1-D nuclear Overhauser effect, distortionless enchancement by polarisation transfer, H,H correlation spectroscopy, heteronuclear multiple quantum coherence, rotating frame Overhauser enhancement spectroscopy spectra and comparison with spectral data of known compounds, the structure of new compounds was established as 1ß,3ß-dihydroxy-olean-9(11),12-dienyl (1). The five known compounds (2-6) were 7α-acetoxyroyleanone, taxodione, salvigenin, apigenin-7,4'-dimethyl ether and ß-sitosterol, respectively. These known structures are isolated from the aerial parts of S. xanthocheila for the first time.


Assuntos
Salvia/química , Triterpenos/química , Clorofórmio/química , Espectroscopia de Ressonância Magnética , Conformação Molecular , Componentes Aéreos da Planta/química , Espectrometria de Massas por Ionização por Electrospray , Triterpenos/isolamento & purificação
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