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1.
ACS Omega ; 6(45): 30241-30259, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34805658

RESUMO

Colebrookea oppositifolia is a folkloric medicinal plant, well known for its tremendous medicinal properties such as curing epilepsy, ulcers, and urinary problems. The aim of the present study was to apply the dereplication strategy on the ethanol extract of C. oppositifolia with potent anti-inflammatory activity for the rapid identification and isolation of novel bioactive molecules to aid the drug discovery process. An integrated approach using liquid chromatography-mass spectrometry (LCMS) followed by preparative high-performance liquid chromatography (HPLC) was used for the isolation of potent molecules from the anti-inflammatory extract of C. oppositifolia . Purity of the compounds (>98.5%) was established by HPLC, and identification was carried out by NMR and ESI-MS. 5,6,7-Trihydroxyflavone-3-O-glucuronide methyl ester (compound III) isolated from C. oppositifolia was extensively studied for anti-inflammatory potential in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and the mice model. Compound III significantly repressed various proinflammatory mediators and upregulated the release of anti-inflammatory cytokine IL-10. Compound III reduced inflammation when studied for parameters such as the phagocytic index, carrageenan-induced paw edema in mice, and effect on organ weight. It reduced inflammation in a dose-dependent manner both in vitro and in vivo. Further molecular insights into the study revealed that compound III blocks the phosphorylation of I kappa b kinase α/ß (IKKα/ß), IκBα, and nuclear factor kB p65 (NF-κBp65) which is a key controller of inflammation, thereby showing anti-inflammatory potential. Hence, this study permits further investigation to develop compound III as an anti-inflammatory drug.

2.
ACS Omega ; 6(30): 19529-19545, 2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34368539

RESUMO

Development of heterogeneous catalysts from biomass-derived activated carbon is a challenging task. Biomass-derived activated carbon possesses a large specific surface area, highly porous structure, and good thermal/chemical stability. Magnetic copper catalysts based on biomass-derived activated carbon exhibited good catalytic activity in base-free Chan-Lam coupling and oxidations. Herein, biomass-derived activated carbon was prepared by the carbonization of neem dead leaves (abundant waste biomass) followed by chemical activation with KOH. Such a porous carbon material was used as a low cost and highly efficient support material for the preparation of inexpensive and environmentally benign magnetic catalysts [Cu@KF-C/MFe2O4, M = Co, Cu, Ni, and Zn]. In addition, KF modification was done to impart basic character to the catalyst that can perform C-N coupling under base-free conditions. Initially, Brunauer-Emmett-Teller (BET) analysis of the synthesized catalysts was carried out, which indicated that Cu@KF-C/CoFe2O4 possess more surface area as well as pore volume, and so accounting for the highest activity among the other synthesized catalysts. Further, X-ray photoelectron spectroscopy (XPS) analysis was performed, which inferred that Cu@KF-C/CoFe2O4 contains most of the copper in reduced form, i.e., Cu(0), which is the active species responsible for better catalytic activity toward Chan-Lam coupling reactions as well as oxidation of alcohols and hydrocarbons. The physiochemical properties of the most active catalyst, Cu@KF-C/CoFe2O4, was examined by BET, XPS, Fourier transform infrared Spectroscopy (FTIR), thermogravimetric analysis (TGA), field emission gun scanning electron microscopy (FEG-SEM), high-resolution transmission electron microscopy (HR-TEM), energy dispersive X-ray (EDX) mapping, energy dispersive X-ray (EDX), inductively coupled plasma atomic emission spectroscopy (ICP-AES), powder X-ray diffraction (XRD), and vibrating sample magnetometry (VSM). Moreover, Cu@KF-C/CoFe2O4 shows excellent stability as well as reusability and could be easily separated with the help of an external magnet.

3.
Bioresour Technol ; 333: 125191, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33951579

RESUMO

This work aimed to study the hydrolysis of ionic liquid (IL) pretreated sugarcane tops (SCT) biomass with in-house developed IL-stable enzyme preparation, from a fungal isolate Aspergillus flavus PN3. Maximum reducing sugar yield (181.18 mg/g biomass) was obtained from tris (2-hydroxyethyl) methylammonium-methylsulfate ([TMA]MeSO4) pretreated biomass. Pretreatment parameters were optimized to attain enhanced sugar yield (1.57-fold). Functional mechanism of IL mediated pretreatment of SCT biomass was elucidated by SEM, XRD, FTIR and 1H NMR studies. Furthermore, nanobiocatalysts prepared by immobilization of enzyme preparation by covalent coupling on magnetic nanoparticles functionalized with amino-propyl triethoxysilane, were assessed for their hydrolytic efficacy and reusability. Nanobiocatalysts were examined by SEM and FTIR analysis for substantiation of immobilization. This is the first ever report of application of magnetic nanobiocatalysts for saccharification of IL-pretreated sugarcane tops biomass.


Assuntos
Líquidos Iônicos , Saccharum , Biocombustíveis , Biomassa , Hidrólise
4.
Heliyon ; 6(4): e03674, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32292828

RESUMO

Self-assembly of nanoscale building blocks plays a critical role for the edifice of functional nanomaterials. In this work coumarin based fused-ring heterocyclic thiol functionalized silver nanoparticle exhibiting large self-assembly is reported. The particles spontaneously self-organise towards the formation of larger superstructures, yet still retaining their individual particle morphology (~10nm). The π-stacking behaviour of coumarin based fused ring aromatic skeleton seems to play the key role for the induction of dense assembly in this hybrid nanoparticles. In the present work the anchoring group (thiol) is directly attached to the aromatic framework of the Coumarin-thiazole fused-ring, for easier electron flow between the metal and the aromatic ligand. The synthesized materials have been characterized by UV-Vis, Fluorescence, XRD, TEM, SAED, IR, 1H and 13C NMR. The synthesis of the ligand and process of functionalization is simple and easily reproducible.

5.
RSC Adv ; 10(50): 30048-30061, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35518227

RESUMO

Herein, well dispersed Ag-Cu NPs supported on modified graphene have been synthesized via a facile and rapid approach using sodium borohydride as a reducing agent under ambient conditions. Dicyandiamide is selected as an effective nitrogen source with TiO2 as an inorganic material to form two kinds of supports, labelled as TiO2-NGO and NTiO2-GO. Initially, the surface area analysis of these two support materials was carried out which indicated that N-doping of GO followed by anchoring with TiO2 has produced support material of larger surface area. Using both types of supports, ten nano-metal catalysts based on Ag and Cu were synthesized. Benefiting from the bimetallic synergistic effect and larger specific surface area of TiO2-NGO, Cu@Ag-TiO2-NGO is found to be a highly active and reusable catalyst out of other synthesized catalysts. It exhibits excellent catalytic activity for oxidation of alcohols and hydrocarbons as well as Chan-Lam coupling reactions. The nanocatalyst is intensively characterized by BET, SEM, HR-TEM, ICP-AES, EDX, CHN, FT-IR, TGA, XRD and XPS.

6.
J Ethnopharmacol ; 211: 295-310, 2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-28962889

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Tinospora cordifolia is a miraculous ayurvedic herb used in the treatment of innumerable diseases such as diabetes, gonorrhea, secondary syphilis, anaemia, rheumatoid arthritis, dermatological diseases, cancer, gout, jaundice, asthma, leprosy, in the treatment of bone fractures, liver & intestinal disorders, purifies the blood, gives new life to the whole body; (rejuvenating herb) and many more. Recent studies have revealed the anticancer potential of this plant but not much work has been done on the anticancer chemical constituents actually responsible for its amazing anticancer effects. This prompted us to investigate this plant further for new potent anticancer molecules. AIM OF THE STUDY: The present study was designed to isolate and identify new promising anticancer candidates from the aqueous alcoholic extract of T. cordifolia using bioassay-guided fractionation. MATERIALS AND METHODS: The structures of the isolated compounds were determined on the basis of spectroscopic data interpretation and that of new potent anticancer molecule, TC-2 was confirmed by a single-crystal X-ray crystallographic analysis of its corresponding acetate. The in vitro anti-cancer activity of TC-2 was evaluated by SRB assay and the autophagic activity was investigated by immunofluorescence microscopy. Annexin-V FITC and PI dual staining was applied for the detection of apoptosis. The studies on Mitochondrial Membrane potential and ROS (Reactive oxygen species) production were also done. RESULTS: Bioassay guided fractionation and purification of the aqueous alcoholic stem extract of Tinospora cordifolia led to the isolation of a new clerodane furano diterpene glycoside (TC-2) along with five known compounds i.e. cordifolioside A (ß-D-Glucopyranoside,4-(3-hydroxy-1-propenyl)- 2,6-dimethoxyphenyl 3-O-D-apio-ß-D-furanosyl) (TC-1), ß-Sitosterol(TC-3), 2ß,3ß:15,16-Diepoxy- 4α, 6ß-dihydroxy-13(16),14-clerodadiene-17,12:18,1-diolide (TC-4), ecdysterone(TC-5) and tinosporoside(TC-6). TC-2 emerged as a potential candidate for the treatment of colon cancer. CONCLUSION: The overall study on the bioassay guided isolation of T.cordifolia identified and isolated a new clerodane furano diterpenoid that exhibited anticancer activity via induction of mitochondria mediated apoptosis and autophagy in HCT116 cells. We have reported a promising future candidate for treating colon cancer.


Assuntos
Diterpenos Clerodânicos/farmacologia , Glicosídeos/farmacologia , Tinospora , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Células HCT116 , Humanos , Caules de Planta
7.
Chem Cent J ; 10: 49, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27493682

RESUMO

BACKGROUND: Boswellia serrata, also known as Indian frankincense is a commercially important medicinal plant which has been used for hundreds of years as an Ayurvedic medicine for the attempted treatment of arthritis. It contains naturally occurring triterpenoic acids, called as boswellic acids (BA's). RESULTS: A highly reproducible High performance liquid chromatography-ultraviolet diode array detection (HPLC-UV-DAD) method was developed for the simultaneous determination and quantitative analysis of eight major triterpenoic acids in Boswellia serrata gum resin obtained by different extraction techniques. All the calibration curves exhibited good linear regression (R(2) > 0.997) within the test ranges. The established method showed good precision and overall recoveries of the boswellic acids. CONCLUSIONS: The eight triterpenoic acids coded as BS-1 (11-keto-beta-boswellic acid), BS-2 (3-O-acetyl-11-keto-beta-boswellic acid), BS-3 (3-keto tirucallic acid), BS-4 (3-O-acetyl-alpha-tirucallic acid), BS-5 (3-O-acetyl-beta-tirucallic acid), BS-6 (alpha-boswellic acid), BS-7 (beta-boswellic acid) and BS-8 (3-O-acetyl-beta-boswellic acid) were isolated from the processed gum resin of Boswellia serrata by column chromatography. The proposed HPLC method is simple, reliable and has been very useful for the qualitative as well as quantitative analysis of boswellic acids in the gum resin of Boswellia serrata. The proposed method allows to quantify boswellic acids in appreciable amounts by HPLC-UV (DAD) method in the extracts and the available marketed formulations.Graphical abstractIsolation & separation of eight Triterpenoic acids from Boswellia serrata.

8.
J Chromatogr Sci ; 54(5): 796-804, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26951542

RESUMO

The present study was conducted to carry out the phytochemical investigation of Tanacetum gracile Hook. f. & Thomson and to develop a method for the simultaneous quantification of the isolated compounds in the extracts ofT. gracile growing in different locations. Cluster analysis rectangular similarity matrix was performed to understand the chemical fingerprinting variations in the extracts. High-performance liquid chromatography-electrospray ionization-quadrupole-time-of-flight-mass spectrometry (HPLC-ESI-QTOF-MS) was used to quantify four bioactive compounds, and separation of the compounds was achieved on a reverse-phase C8 column using a mobile phase of acetonitrile: 0.1% formic acid in water with a gradient elution by maintaining the flow rate of 300 µL/min. The QTOF-MS was operated using the electro-spray ionization technique with the positive ion polarity mode. The calibration curves of four marker compounds were linear over the concentration range of 3.12-100 ng/µL (R(2)> 0.996). A specific, accurate and precise HPLC-ESI-QTOF-MS method was optimized for the determination of kaempferol, ketoplenolide, tetramethoxyflavone and artemetin both individually and simultaneously. Quantification of these chemical markers in different extracts was carried out using this validated method. Kaempferol was isolated for the first time from T. gracile.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Tanacetum/química , Espectrometria de Massas em Tandem/métodos , Limite de Detecção , Reprodutibilidade dos Testes
9.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 10): o805-6, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26594489

RESUMO

In the title compound C27H22Cl2N4O2, the pyrazol-5-ol ring makes a dihedral angle of 34.80 (11)° with the phenyl ring to which it is bound, while the pyrazolone ring is inclined at 34.34 (12)° to its attached phenyl ring. In the crystal, N-H⋯O and C-H⋯Cl hydrogen bonds link the mol-ecules into chains along [010]. Inter-molecular π-π inter-actions are observed between the pyrazolone ring and the phenyl ring bound to the pyrazol-5-ol ring system [centroid-centroid separation = 3.916 (2) Å].

10.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 8): o534-5, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26396783

RESUMO

In the title compound, C15H12FN3O, the triazole ring forms dihedral angles of 30.57 (8) and 21.81 (9)° with the fluoro-substituted and meth-oxy-substituted benzene rings, respectively. The dihedral angle between the benzene rings is 51.53 (7)°. In the crystal, π-π inter-actions between the triazole rings [centroid-centroid seperations = 3.774 (2) and 3.841 (2) Å] form chains along [010].

11.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 9): o669, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26396895

RESUMO

In the title compound, C20H17ClN2O2S, the dihedral angle between the planes of the benzo-thia-zole fused ring system (r.m.s. deviation = 0.024 Å) and the chloro-benzene ring is 89.62 (12)°. The ester C-O-C-C side chain has an anti orientation [torsion angle = -155.2 (3)°]. In the crystal, weak aromatic π-π stacking inter-actions are observed between the phenyl and pyrimidine rings [centroid-centroid seperation = 3.666 (2) Å].

12.
Pharmacogn Rev ; 9(17): 81-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26009697

RESUMO

Sarcochlamys pulcherrima (Roxb.) Gaud. is widely used as traditional medicine and food by different tribes and communities of Assam in India and in neighboring countries. Recent studies conducted in our laboratory showed the broad-spectrum antimicrobial and antioxidant activities of its crude extract and different solvent fractions and detected the presence of phenolics, flavonoids, saponin, and acidic compounds. This review gives a bird's eye view of the traditional uses of S. pulcherrima as food and medicine based on the information gathered by personal interaction with the people of different places of Assam as well as the investigations made on its ethno-botanical claims, biological activities, and other aspects by various workers since years till date and highlight the prospects of future research.

13.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 4): o1185-6, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22606126

RESUMO

In the title 1:1 co-crystal, C(10)H(7)BrN(4)S·C(7)H(5)BrO(2), the triazolothia-diazole system is approximately planar [with a maximum deviation of 0.030 (4) Å] and forms a dihedral angle of 8.6 (1)° with the bromo-phenyl ring. In the carb-oxy-lic acid mol-ecule, the carboxyl group is rotated by 6.4 (3)° out of the benzene ring plane. The crystal structure features O-H⋯N and C-H⋯O hydrogen bonds, π-π stacking inter-actions [centroid-centroid distances = 3.713 (2), 3.670 (2) and 3.859 (3) Å] and short S⋯N [2.883 (4) Å] contacts.

14.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 11): o3077, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23284410

RESUMO

In the title compound, C(14)H(12)ClNO(2), the mean plane through the amide group [-N-C=O-] forms dihedral angles of 27.55 (8) and 31.94 (7)° with the meth-oxy- and chloro-substituted benzene rings, respectively. The dihedral angle between the benzene rings is 59.24 (4)°. In the crystal, N-H⋯O and weak C-H⋯O hydrogen bonds link the mol-ecules into chains along the a axis.

15.
Int J Biol Macromol ; 49(5): 930-5, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21871916

RESUMO

Nano palladium(0) supported on cellulose was found to be highly efficient recyclable heterogeneous catalyst for the Suzuki coupling between aryl bromides and phenyl boronic acid in water and aerobic oxidation of benzyl alcohols using air as the source of molecular oxygen in acetonitrile. The Cell-Pd(0) was prepared by stirring commercially available cellulose with Pd(OAc)(2) in ethanol at 25°C followed by reduction with hydrazine hydrate, leading finally to nano Pd(0) particles uniformly distributed on surface of cellulose. This catalytic system provides biaryls and polyaryls in excellent yields with very high turn over numbers via Suzuki coupling; and benzaldehyde derivatives in high yields and selectivity by oxidation in air. Cell-Pd(0) was characterized by X-ray diffraction techniques (XRD), thermal analysis (TGA), scanning electron microscope (SEM) and transmission electron microscope (TEM).


Assuntos
Álcoois Benzílicos/química , Química Orgânica/métodos , Nanopartículas/química , Oxigênio/química , Paládio/química , Acetonitrilas/química , Ácidos Borônicos/química , Catálise , Celulose/química , Reutilização de Equipamento , Etanol/química , Hidrazinas/química , Ligantes , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Oxirredução , Água , Difração de Raios X
16.
Eur J Med Chem ; 46(2): 631-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21185625

RESUMO

A simple, efficient and environment-friendly procedure is developed for the synthesis of 1-substituted-8-aryl-3-alkyl/aryl-4H-pyrazolo[4,5-f][1,2,4]triazolo[4,3-b][1,2,4]triazepines in the presence of N,N-dimethylformamide as an energy transfer medium, p-TsOH as catalyst and basic alumina as solid support under microwave irradiation. The products are obtained in moderate to good yields and are in a state of high purity. Moreover, title compounds have been screened for antifungal activity.


Assuntos
Antifúngicos/farmacologia , Aspergillus flavus/efeitos dos fármacos , Aspergillus niger/efeitos dos fármacos , Azepinas/farmacologia , Penicillium/efeitos dos fármacos , Rhizopus/efeitos dos fármacos , Triazóis/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Azepinas/síntese química , Azepinas/química , Testes de Sensibilidade Microbiana , Micro-Ondas , Estrutura Molecular , Estereoisomerismo , Triazóis/síntese química , Triazóis/química
17.
Bioinformation ; 4(10): 473-7, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20975912

RESUMO

TtgR is a multi-drug binding protein in the gram negative bacteria Pseudomonas putida (DOT-T1E strain) and regulates one of the key mechanisms of its antibiotic resistance by active extrusion of toxic compounds through the membrane-bound efflux pumps. The paper reports the molecular docking studies of Pongachalcone I, a natural pyranochalcone and reported potent inhibitor of the bacteria, on the transcriptional regulator (TtgR) enzyme (PDB Code: 2UXI) which is a key efflux pump TtgABC operon repressor. Although the bacterium is capable to expel antibiotics like Chloramphenicol, Tetracycline and Naringenin, yet Pongachalcone I has potent activity against it. The work unveils the key roles played by the residues ASN 110 and CYS 137 in the active site of the enzyme, which would be highly beneficial in providing insight into the molecular mechanism of multiple drug recognition and in designing drugs for antibiotic resistance bacteria.

18.
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