Isolation and Identification of Bioactive Compounds from Bidens spp. Using HPLC-DAD and GC-MS Analysis and Their Biological Activity as Anticancer Molecules

The genus Bidens a member of family Compositae, is widely documented as an ethno-medicinally important genus of plants. In the present study, anticancer potential of three ethno-medicinally important species i.e., B. bipinnata, B. biternata and B. pilosa were tested. For in-vitro evaluation, an MTT (Thiazolyl blue tetrazolium bromide) assay was performed against cervical cancer cells (HeLa), hepatocellular carcinoma (HepG), and adenocarcinoma human alveolar basal epithelial cells (A549). For in vivo evaluation, Artemia salina, Danio rerio, and Caenorhabditis elegans were used. Among all the tested extracts, the ethanol extract of B. biternata appeared to have highest anticancer activity, and the compounds responsible for this activity were identified to be Tris (2,4-di-tert-butylphenyl), 4-hydroxy-2,4′-dimethoxychalcone, and 2,4-di-tert-butylphenol. This is the first report of the isolation of Tris (2,4-di-tert-butylphenyl) phosphate from the genus Bidens and the first report of 4-hydroxy-2,4′-dimethoxychalcone and 2,4-di-tert-butylphenol from B. biternata. Among the isolated compounds, 4-hydroxy-2,4′-dimethoxychalcone showed the highest anticancer activity with an LD50 value of 236.7 µg/mL. Therefore, this compound carries promising potential for being established as a pharmaceutical for chemoprevention and chemotherapy.     

Numerical Analysis of Unsteady Magneto-Biphase Williamson Fluid Flow with Time Dependent Magnetic Field

Numerical investigation of the dusty Williamson fluid with the dependency of time has been done in current disquisition. The flow of multiphase liquid/particle suspension saturating the medium is caused by stretching of porous surface. The influence of magnetic field and heat generation/absorption is observed. It is assumed that particle has a spherical shape and distributed uniformly in fluid matrix. The unsteady two-dimensional problems are modeled for both fluid and particle phase using conservation of mass, momentum and heat transfer. The finalized model generates the non-dimensioned parameters, namely Weissenberg number, unsteadiness parameter, magnetic parameter,heat generation/absorption parameter, Prandtl number, fluid particle interaction parameter, and mass concentration parameters. The numerical solution is obtained. Locality of skin friction and Nusselt number is deliberately focused to help of tables and graphs. While inferencing the current article it is clearly observed that increment of Williamson parameter, unsteadiness parameter, magnetic parameter, volume fraction parameter, and mass concentration parameter reduces the velocity profile of fluid and solid particles as well. And increment of Prandtl number, unsteadiness parameter,volume fraction parameter, and mass concentration parameter reduces the temperature profile of fluid and solid particles as well.     

Honey mediated microwave assisted sol–gel synthesis of stabilized zirconia nanofibers

Aim of the present work is to prepare zirconia nanofibers using microwave assisted sol–gel method. Both honey and microwave powers are employed as structure directing agents to improve the stability and reduce the crystallite size. Honey, acting as capping agent, prevents the particles from hard agglomeration. Soft agglomeration or less agglomeration results in smaller crystallite size that prevents the transformation of tetragonal to monoclinic phase resulting in stabilized tetragonal zirconia (t-ZrO₂). Zirconium oxychloride is used as precursor of zirconium and deionized water as solvent. Effect of microwave powers, in the range of 100–900?W with interval of 200?W, on zirconia stabilization is observed. X-ray diffraction analysis shows the presence of phase pure t-ZrO₂ at low microwave power ~?100?W with crystallite size ~?26?nm. Formation of phase pure t-ZrO₂ at low microwave power is due to the presence of sufficient amount of honey to coat the zirconia crystals. Relatively higher x-ray density has been observed in case of phase pure t-ZrO₂ at 100?W of microwave power. This high density and phase purity reveals the high value of hardness (~?1503?HV). Scanning electron microscopy analysis reveals the formation of well-separated nanofibers without agglomeration at 100?W. These nanofibers are purposed for bone implants and bone grafting. Structural transformation along with hard agglomeration is observed with increase in microwave powers from 500?W to 900?W. FTIR and Raman fundamental tetragonal bands, appearing at 490?cm^?1 and 148?cm^?1, respectively, confirm the formation of t-ZrO₂ at low microwave power. Sample with phase purity exhibits high grain boundary resistance (1.95?MΩ) along with high dielectric constant (~?74) and low tangent loss (at log f?=?4.0). It is worth mentioning here that phase pure t-ZrO₂ at very low microwave power (~100?W) with high density and well-separated nanofibers has been obtained without any post heat treatment.

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Micellar parameters of diblock copolymers and their interactions with ionic surfactants

The interactions of non-ionic amphiphilic diblock copolymer poly（oxyethylene/oxybutylene）(E₃₉B₁₈) with anionic surfactant sodium dodecyl sulphate（SDS） and cationic surfactant hexadecyltrimethylammonium bromide（CTAB） were studied by using various techniques such as surface tension,conductivity,steady-state fluorescence and dynamic light scattering.Surface tension measurements were used to determine the critical micelle concentration（CMC） and thereby the free energy of micellization(△G_mic),free energy of adsorption(△G_ads),surface excess concentration（Γ） and minimum area per molecule（A）.Conductivity measurements were used to determine the critical micelle concentration（CMC）,critical aggregation concentration（CAC）,polymer saturation point（PSP）,degree of ionization（α） and counter ion binding（β）. Dynamic light scattering experiments were performed to check the changes in physiochemical properties of the block copolymer micelles taken place due to the interactions of diblock copolymers with ionic surfactants.The ratio of the first and third vibronic peaks（I₁/I₃） indicated the polarity of the pyrene micro environment and was used for the detection of micelle as well as polymer-surfactant interactions.Aggregation number（N）,number of binding sites（n） and free energy of binding （△G_b） for pure surfactants as well as for polymer-surfactant mixed micellar systems were determined by the fluorescence quenching method.     

Protease Inhibitors Purified from the Canola Meal Extracts of Two Genetically Diverse Genotypes Exhibit Antidiabetic and Antihypertension Properties

Valorization of vegetable oil waste residues is gaining importance due to their high protein and polyphenol contents. Protease inhibitors (PIs), proteins from these abundantly available waste residues, have recently gained importance in treating chronic diseases. This research aimed to use canola meal of genetically diverse Brassica napus genotypes, BLN-3347 and Rivette, to identify PIs with diverse functionalities in therapeutic and pharmacological applications. The canola meal PI purification steps involved: native PAGE and trypsin inhibition activity, followed by ammonium sulfate fractionation, anion exchange, gel filtration, and reverse-phase chromatography. The purified PI preparations were characterized using SDS-PAGE, isoelectric focusing (IEF), and N terminal sequencing. SDS-PAGE analysis of PI preparations under native reducing and nonreducing conditions revealed three polymorphic PIs in each genotype. The corresponding IEF of the genotype BLN-3347, exhibited three acidic isoforms with isoelectric points (pI) of 4.6, 4.0, and 3.9, while Rivette possessed three isoforms, exhibiting two basic forms of pI 8.65 and 9.9, and one acidic of pI 6.55. Purified PI preparations from both the genotypes displayed dipeptidyl peptidase-IV (DPP-IV) and angiotensin-converting enzyme (ACE) inhibition activities; the BLN-3347 PI preparation exhibited a strong inhibitory effect with lower IC₅₀ values (DPP-IV 37.42 µg/mL; ACE 129 µg/mL) than that from Rivette (DPP-IV 67.97 µg/mL; ACE 376.2 µg/mL). In addition to potential human therapy, these highly polymorphic PIs, which can inhibit damaging serine proteases secreted by canola plant pathogens, have the potential to be used by canola plant breeders to seek qualitative trait locus (QTLs) linked to genes conferring resistance to canola diseases.     

Organotin(IV) Complexes of 2-[(2′,4′,6′- Trichlorophenylamido)]benzoic Acid: Synthesis,Coordination Chemistry,and Semi-Empirical Study

A new series of organotin(IV) complexes of aniline derivatives, R₂SnL₂ and R₃SnL [where R = Me, n-Bu, n-Oct, and Ph], have been synthesized by the reaction of ligand acid with respective organotin halides in the presence of triethylamine as base or dioctyltin oxide using a Dean–Stark trap for the removal of water under reflux conditions. Experimental details for the preparation and characterization, including elemental analysis, IR, semi-empirical study, multinuclear NMR (¹H, ¹³C, and ¹¹⁹Sn spectra and EI mass spectral studies) of all reported complexes are provided. The IR data indicate that in both di- and triorganotin(IV) carboxylates, the ligand moiety ?COO acts as a bidentate group in the solid state. Multinuclear NMR data show that triorganotin complexes exhibits a four-coordinated geometry, while diorganotin(IV) complexes show a coordination number greater than four, probably five or six, in solution state.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Synthesis,Characterization, and Semi-Empirical Study of Organotin(IV) Complexes with 4-(Hydroxymethyl)piperidine-1-carbodithioic Acid: X-Ray Structure of Chlorodimethyl-(4-hydroxymethyl piperidine-1-carbodithioato-S,S′)tin(IV)

Abstract

Organotin complexes with the general formulae R₂SnL₂, R₂Sn(Cl)L, and R₃SnL have been synthesized where R = CH₃, n-C₄H₆, C₆H₅, C₆H₁₁, and L = 4-(hydroxy methyl)piperidine-1-carbodithioic acid. The newly synthesized complexes have been characterized by elemental analysis, IR, NMR (¹H, ¹³C and ¹¹⁹Sn), and, for one example, a single crystal x-ray structure. The FT-IR data shows the bidentate nature of the ligand. This coordination behavior is also confirmed by semi-empirical study. In the solid state, diorganotin complexes exhibit the penta/hexacoordinated geometry, whereas the triorganotin(IV) complexes show the five coordinated geometry. ¹¹⁹Sn NMR data reveal that triorganotin(IV) complexes exhibit the four coordinated geometry in solution, whereas the diorganotin(IV) compounds show the higher coordination, probably five or six. X-ray diffraction analysis of complex (2) shows a square pyramidal geometry around the tin atom on the basis of τ value.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.

GRAPHICAL ABSTRACT      

A resonance Raman,surface-enhanced resonance Raman,IR, and ab initio vibrational spectroscopic study of nickel(II) tetraazaannulene complexes

The IR and resonance Raman spectra of the nickel(II) complexes of dibenzo[b,i][1,4,8,11]tetraaza[14]annulene (TAA) and 5,7,12,14-tetramethyldibenzo[b,i][1,4,8,11]tetraaza[14]annulene (TMTAA) have been measured and compared with ab initio calculations of the vibrational wavenumbers at the B3-LYP level using the LanL2DZ basis set. An excellent fit is found between the experimental and calculated data, enabling precise vibrational assignments to be made. Surface-enhanced resonance Raman spectra were obtained following adsorption on Ag electrodes, with potentials in the range -0.1 to -1.1 V vs Ag/AgCl. There is evidence for contributions from both the electromagnetic and charge transfer (CT) surface enhancement mechanisms. The data indicate that variations in band intensities with electrode potential can be interpreted in terms of the CT mechanism.