Anti-inflammatory and anticancer activities of erythrodiol-3-acetate and 2,4-di-tert-butylphenol isolated from Humboldtia unijuga

Abstract

Humboldtia unijuga Bedd., endemic to Agasthyamala in Western Ghats in India, is traditionally used by local Kani tribes for chicken pox, head ache and snake bite. This study reports the isolation of erythrodiol-3-acetate (HU-1) and 2,4-di-tert-butylphenol (HU-2) from H. unijuga roots and their anti-inflammatory and anticancer activities in macrophage, skin and breast cancer cell lines. Effects of HU-1 and HU-2 treatments (50, 100?µg/mL) on gene expression profiles of pro-inflammatory cytokines TNFα, IL-6 and IL-1β, and apoptosis genes p53 and caspase 7 were studied. HU-2 exerted a significantly superior anti-inflammatory effect compared to HU-1 in all three pro-inflammatory genes. HU-2 showed a superior dose dependent anticancer effect through activation of p53 gene over HU-1 in MCF-7 cells. HU-1 exhibited a dose dependent effect on caspase 7 gene in both cell lines while HU-2 was more effective in A431. HU-2 has potential for development as a novel anti-inflammatory and anticancer agent.     

Effect of Yb addition on the superconducting properties of (Bi,Pb)-2212 superconductor

The effects of Yb addition on the phase evolution and superconducting properties of (Bi,Pb)-2212 superconductor prepared by solid state synthesis in the polycrystalline form were studied. Yb content of the samples was varied (x = 0–0.5) on a general stoichiometry of Bi_1.7Pb_0.4Sr_2.0Ca_1.1Cu_2.1Yb_xO_y. Phase analysis by XRD, microstructural examination by SEM, measurements of density and superconducting properties were done to evaluate the relative performance of the samples. A Yb containing secondary phase could be distinguished from XRD analysis from Yb > 0.3 in the stoichiometric level. Microstructural examination showed clear and distinct morphological variation with Yb stoichiometry and a secondary phase with round edged grains was observed in the microstructure of Yb added samples. The critical current density (J_C) and superconducting transition temperature (T_C) of all the Yb added samples were found to be higher than that of the pure sample. A maximum T_C-onset of 94.5 K and a maximum J_C 688 A/cm² has been observed for the sample with Yb = 0.2 in the stoichiometric level. Above this level T_C and J_C began to reduce, may be due to secondary phase formation.     

Reaction of diaryl-1,2-diones with triphenylphosphine and diethyl azodicarboxylate leading to N,N-dicarboethoxy monohydrazones via a novel rearrangement

[reaction: see text]. A mechanistically novel reaction of diaryl-1,2-diones with diethyl azodicarboxylate and triphenylphosphine to afford N,N-dicarboethoxy monohydrazones is described. The reaction proceeds via a nitrogen to nitrogen migration of a carboethoxy group.     

Synthesis and Crystal Structure of [Mn2(H2sal)2(Hsal)2(H2O)4]. First Example of the Reductive Synthesis of a Binuclear Manganese(I) Salicylate Complex

The synthesis and characterization of the first unique binuclear manganese(I) salicylate complex is described. The structure of the complex is unequivocally established with the help of an X-ray crystallographic study. The structure consists of two [MnO₆] units, containing octahedral Mn^I ions, linked together by a bridging salicylato (Hsal⁻) ligand and each Mn^I is chelated with a (H₂sal) ligand. The complex possesses a metal oxidation state of +1 and is a rare example of a noncarbonyl or cyanide complex of a binuclear Mn^I species. The effective magnetic moment per binuclear molecule (μ_eff. at 27 °C is 8.07 μ_b, that also describes the manganese (+1) oxidation state.     

Selective complexometric determination of mercury using sodium nitrite as masking agent

A complexo-titrimetric method for the determination of mercury(II) in the presence of other metal ions is described based on the selective masking ability of sodium nitrite. Mercury and other ions are initially complexed with an excess of EDTA and the surplus EDTA is titrated with Pb(NO₃)₂ solution at pH 5.0–6.0 using xylenol orange as indicator. An excess of solid NaNO₂ is then added to decompose the Hg(II)-EDTA complex and the released EDTA is titrated with standard Pb(NO₃)₂ solution. Accurate results were obtained for 10–65 mg of mercury with relative errors <0.3% and standard deviations < 0.03 mg. Sn(IV) and Pd(II) interfere but can be easily masked. The method is applied for the determination of Hg(II) in its alloy compositions and complexes.     

Redox Mediated Synthesis of Ag-CuO Hybrid Nanoparticles – DNA/BSA Binding Studies and in vitro Evaluation of Anti-cancer Activity on MCF-7 Cancer Cell Line

We herein report a nanoparticle-directed therapeutic approach to breast cancer using Ag-CuO hybrid nanoparticles. The nanoparticles were synthesized through redox-mediated process involving reduction of silver ion on the surface of Cu₂O nanostructures. Structural, microstructural and optical characterization were carried out and the hybrid nanoparticles were found to be phase pure with crystallite size between 100–200 nm and the absorption due to surface plasmon resonance from silver was observed around 460 nm. The binding affinities of the hybrid nanoparticles with the plasma protein BSA and calf thymus DNA were studied and the respective binding constants were found to be 5.1 × 10⁴ and 1.12 × 10⁵ M⁻¹ showing appreciable binding affinity of the substrate. The cytotoxicity of the as-synthesized hybrid nanoparticles induced in breast cancer cells was evaluated in vitro and the obtained results demonstrates the potential anti-cancer activity of the Ag-CuO hybrid nanoparticles against the MCF-7 breast cancer cell line.     

Nonradiative Energy Transfer through Distributed Bands in Piezochemically Synthesized Cesium and Formamidinium Lead Halide Perovskites

Repeated absorption of emitted photons, also called photon recycling, in large crystals and thick films of perovskites leads to delayed photoluminescence (PL) and decrease of PL intensity. The role of distinct band gaps, which act as donors and acceptors of energy, and nonradiative energy transfer on such delayed, low intensity emission is yet to be rationalized. Here we report delayed emission by nonradiative energy transfer across a distribution of energy states in close-packed crystallites of cesium lead bromide CsPbBr₃, formamidinium lead bromide FAPbBr₃, or the mixed halide FAPb(BrI)₃ perovskite synthesized in the form of thick pellets by the piezochemical method. The PL lifetime of the bromide-rich domain in the mixed halide pellet is considerably decreased when compared with a pure FAPbBr₃ pellet. Here the domains with higher bromide composition act as the energy donor, whereas the iodide-rich domains are the acceptors. Time-resolved PL measurements of CsPbBr₃, FAPbBr₃, and the mixed halide FAPb(BrI)₃ perovskite pellets help us to clarify the role of nonradiative energy transfer on photon recycling.     

Effect of post-annealing on the band gap of sol–gel prepared nano-crystalline Mg x Zn1−x O (0.0 ≤ x ≤ 0.3) thin films

Polycrystalline Mg _x Zn_1?x O (MZO) thin films on glass substrates were prepared by sol–gel method. All the films retained the hexagonal wurtzite structure of ZnO. The band gap values determined from transmission spectra were found to be smaller than the values obtained from Vegard’s law for the as-deposited MZO films. For the films with x = 0.1, 0.2 and 0.3, the band gap blue-shifted initially and then red-shifted with increase in the annealing temperature. The reason for this anomalous shift in the band gap is attributed to the proper substitution of Mg atoms into the Zn lattice sites after a certain critical annealing temperature.