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1.
Appl Biochem Biotechnol ; 194(11): 5037-5059, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35687306

RESUMEN

Pleurolobus gangeticus (L.) J. St.- Hil. ex H. Ohashi & K. Ohashi (Fabaceae) is an important medicinal plant used to treat various ailments. In this study, we report the antiurolithiatic, antioxidant, and antibacterial potential of chloroform fraction (CF) from P. gangeticus roots. For the chemical profiling, HPTLC, FT-IR, and GC-MS techniques of the CF were carried out, and phytochemical investigation was revealed that stigmasterol (45.06%) is one of the major components present in the fraction. The nucleation and aggregation assays were used to evaluate the in vitro antiurolithiatic activity at various concentration (2-10 mg/mL) of the CF. The results showed that the chloroform fraction had dose-dependent effects on Calcium Oxalate (CaOx) crystal formation. In both the assays, the maximum concentration of 10 mg/mL has shown better results. This concentration resulted significant increase in CaOx crystal nucleation along with the reduction of crystal size and the inhibition of crystal aggregation. Further, the CF showed stronger antioxidant (DPPH, NO, SOD, TRC) potential with an IC50 values of 415.9327, 391.729, 275.971, and 419.14 µg/mL, respectively. The antibacterial evaluation displayed effective results in the Agar well diffusion assay against selective urinary tract infection (UTI) pathogens (Escherichia coli, Klebsiella pneumonia, and Staphylococcus aureus). A maximum zone of inhibition (ZOI) 12.33 ± 1.05 mm for K pneumonia and minimum ZOI of 8.46 ± 0.27 mm for S. aureus were obtained. Further, the ADME-PK property of the stigmasterol was investigated, and it was found to pass the Lipinski and Ghose rules, supporting the drug-likeliness. This is the first record of the antiurolithiatic potential of P. gangeticus along with antioxidant and antibacterial activities. These findings give an insight into the effective drug development and treatment for kidney stones in future.


Asunto(s)
Antioxidantes , Fabaceae , Antioxidantes/farmacología , Antioxidantes/química , Oxalato de Calcio/química , Staphylococcus aureus , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Cloroformo , Estigmasterol/farmacología , Agar , Espectroscopía Infrarroja por Transformada de Fourier , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Fitoquímicos/farmacología , Superóxido Dismutasa
2.
Mater Today Bio ; 12: 100131, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34622194

RESUMEN

Recent advancement in nanotechnology seeks exploration of new techniques for improvement in the molecular, chemical, and biological properties of nanoparticles. In this study, carbon modification of octahedral-shaped magnetic nanoparticles (MNPs) was done using two-step chemical processes with sucrose as a carbon source for improvement in their electrochemical application and higher molecular biocompatibility. X-ray diffraction analysis and electron microscopy confirmed the alteration in single-phase octahedral morphology and carbon attachment in Fe3O4 structure. The magnetization saturation and BET surface area for Fe3O4, Fe3O4/C, and α-Fe2O3/C were measured as 90, 86, and 27 emu/g and 16, 56, and 89 m2/g with an average pore size less than 7 nm. Cyclic voltammogram and galvanostatic charge/discharge studies showed the highest specific capacitance of carbon-modified Fe3O4 and α-Fe2O3 as 213 F/g and 192 F/g. The in vivo biological effect of altered physicochemical properties of Fe3O4 and α-Fe2O3 was assessed at the cellular and molecular level with embryonic zebrafish. Mechanistic in vivo toxicity analysis showed a reduction in oxidative stress in carbon-modified α-Fe2O3 exposed zebrafish embryos compared to Fe3O4 due to despaired influential atomic interaction with sod1 protein along with significant less morphological abnormalities and apoptosis. The study provided insight into improving the characteristic of MNPs for electrochemical application and higher biological biocompatibility.

3.
Chempluschem ; 85(6): 1137-1144, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32490594

RESUMEN

A vanadium formate (VF) coordination polymer and its composite with partially reduced graphene oxide (prGO), namely VF-prGO, can be applied as anode materials for Li-ion based electrochemical energy storage (EcES) systems in the potential range of 0-3 V (vs Li+ /Li). This study shows that a reversible capacity of 329 mAh g-1 at a current density of 50 mA g-1 after 50 cycles can be realized for VF along with a high rate capability. The composite exhibits even a higher capacity of 504 mAh g-1 at 50 mA g-1 . A good capacity retention is observed even after 140 cycles for both VF and the composite. An ex-situ X-ray photoelectron spectroscopy study indicates the involvement of V3+ /V4+ redox couple in the charge storage mechanism. A significant contribution of this reversible capacity is attributed to the pseudocapacitive behavior of the system.

4.
J Genet Eng Biotechnol ; 16(2): 363-367, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30733747

RESUMEN

Inulinase are industrial food enzymes which have gained much attention in recent scenario. In this study, Inulinase producing eight bacterial colonies were isolated and screened from three different plant root tubers soil sample. Among 8 inulinase producing colonies, the higher yielding colony was selected with 25.10 U/mL for further studies. The best inulinase producing colony was identified by partial 16S rRNA gene sequence as Bacillus sp. The crude inulinase was purified by using ammonium sulphate precipitation, dialysis and ion exchange chromatography on DEAE - sephacel and obtained 1.9 purification fold with total activity 293 U. The purified enzyme was subjected to characterization studies and it was found to be stable at 30-60 °C and optimum temperature was at 55 °C. The enzyme was stable at pH 3.0-7.0 and optimum pH was at 6.5. The Km and Vmax value for inulinase was found to be 0.117 mg/mL and 4.45 µmol min mg-1 respectively, demonstrate its greater affinity. Hence, this enzyme can be widely used for the production of fructose, and fructooligosaccharides, which are important ingredients in food and pharmaceutical industry.

5.
J Am Chem Soc ; 136(22): 7801-4, 2014 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-24815319

RESUMEN

Two analogous metal-organic frameworks (MOFs) with the perovskite architecture, [C(NH2)3][Mn(HCOO)3] (1) and [(CH2)3NH2][Mn(HCOO)3] (2), exhibit significantly different mechanical properties. The marked difference is attributed to their distinct modes of hydrogen bonding between the A-site amine cation and the anionic framework. The stronger cross-linking hydrogen bonding in 1 gives rise to Young's moduli and hardnesses that are up to twice those in 2, while the thermal expansion is substantially smaller. This study presents clear evidence that the mechanical properties of MOF materials can be substantially tuned via hydrogen-bonding interactions.

6.
Chem Commun (Camb) ; 49(40): 4471-3, 2013 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-23571480

RESUMEN

We report the mechanical properties of a framework structure, [Cu2F(HF)(HF2)(pyz)4][(SbF6)2]n (pyz = pyrazine), in which [Cu(pyz)2](2+) layers are pillared by HF2(-) anions containing the exceptionally strong F-H···F hydrogen bonds. Nanoindentation studies on single-crystals clearly demonstrate that such bonds are extremely robust and mechanically comparable with coordination bonds in this system.


Asunto(s)
Cobre/química , Fluoruros/química , Compuestos Organometálicos/química , Pirazinas/química , Enlace de Hidrógeno
7.
J Am Chem Soc ; 134(29): 11940-3, 2012 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-22758218

RESUMEN

A 3D hybrid zinc formate framework, [NH(4)][Zn(HCOO)(3)], possessing an acs topology, shows a high degree of mechanical anisotropy and negative linear compressibility (NLC) along its c axis. High-pressure single-crystal X-ray diffraction studies and density functional theory calculations indicate that contraction of the Zn-O bonds and tilting of the formate ligands with increasing pressure induce changes in structure that result in shrinkage of the a and b axes and the NLC effect along c.

8.
Dalton Trans ; 41(14): 4126-34, 2012 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-22378230

RESUMEN

Six inorganic-organic bismuth 2,6-pyridinedicarboxylate (pdc) compounds, [Bi(2,6-pdc)(3)]·3(dma), 1, [Bi(2,6-pdc)(3)]·3(dma)·2(H(2)O), 2, [Bi(2,6-pdc)(2)(dmf)]·(dma), 3, Bi(2,6-pdc)(2,6-pdcme)(MeOH), 4, [LiBi(2,6-pdc)(3)(H(2)O)]·2(dma), 5, and Li(5)Bi(2,6-pdc)(4)(H(2)O)(2), 6 (where dma = dimethyl ammonium cation, dmf = dimethylformamide and 2,6-pdcme = 6-methyl-oxycarbonyl pyridine 2-carboxylate) have been synthesized under solvothermal conditions and their structures determined by single crystal X-ray diffraction. Compounds 1-4 have molecular structures whereas compounds 5 and 6 form one- and three-dimensional frameworks, respectively. Compounds 1 and 2, both having similar monomeric bismuth coordination units, which are connected non-covalently into a (4,4)-connected square lattice by H-bonding interactions through dma cations. Compounds 3 and 4, both have a similar dimeric bismuth coordination unit. In 3, the dimers are connected into a one-dimensional chain by H-bonding interactions through dma cations. In the partially esterified and neutral 4, there was no such H-bonding interactions due to the absence of any dma cations. Compounds 5 and 6 have a similar monomeric bismuth coordination unit to that seen in 1 and 2. In 5, the monomers are connected through lithium cations into one-dimensional chains, which further interact non-covalently by H-bonding interactions through dma cations. In the lithium-rich 6, the monomers are connected by the lithium cations and 2,6-pdc anions into a three dimensional structure with intramolecular H-bonding interactions involving the water molecules. The non-porous 5 and 6 exhibit a reasonable amount of H(2) and CO(2) sorptions, respectively. Tb(3+)- and Eu(3+)-doped and co-doped 4 and 5 emit characteristic sensitized green/red/yellow-orange luminescence.

10.
Chemistry ; 16(35): 10684-90, 2010 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-20806296

RESUMEN

The dense, anhydrous zeolitic imidazolate frameworks (ZIFs), Zn(Im)(2) (1) and LiB(Im)(4) (2), adopt the same zni topology and differ only in terms of the inorganic species present in their structures. Their mechanical properties (specifically the Young's and bulk moduli, along with the hardness) have been elucidated by using high pressure, synchrotron X-ray diffraction, density functional calculations and nanoindentation studies. Under hydrostatic pressure, framework 2 undergoes a phase transition at 1.69 GPa, which is somewhat higher than the transition previously reported in 1. The Young's modulus (E) and hardness (H) of 1 (E≈8.5, H≈1 GPa) is substantially higher than that of 2 (E≈3, H≈0.1 GPa), whilst its bulk modulus is relatively lower (≈14 GPa cf. ≈16.6 GPa). The heavier, zinc-containing material was also found to be significantly harder than its light analogue. The differential behaviour of the two materials is discussed in terms of the smaller pore volume of 2 and the greater flexibility of the LiN(4) tetrathedron compared with the ZnN(4) and BN(4) units.

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