Karnataka Science College

Dharwad, India

Karnataka Science College

Dharwad, India

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Chavan P.,Karnatak University | Naik L.R.,Karnatak University | Belavi P.B.,Gogte Institute of Technology | Chavan G.N.,Karnataka Science College | Kotnala R.K.,National Physical Laboratory India
Journal of Alloys and Compounds | Year: 2017

Bi3+ substituted Ni-Cu ferrites with the particles size 0.28 μm–0.53 μm were prepared by solid state reaction method. X-ray diffraction analysis confirmed the single phase cubic spinel structure with the space group of Fd3m-Oh 7. IR absorption bands assigned at 580 cm−1 and 403 cm−1 corresponds to the stretching of vibrations of tetrahedral and octahedral complexes of the ferrites. The average grain sizes of the ferrites were estimated by SEM micrographs at around 1.04 μm which was found to be increased with Bi content. The decrease of DC resistivity as a function of temperature shows the semiconducting nature of ferrites and is attributed to the increase in thermally activated drift mobility of charge carriers. The dielectric constant decreases with increase in the frequency of all samples shows dispersion behavior. Hysteresis loop of the ferrites at room temperature were studied for the determination of saturation magnetization and magnetic moment. The maximum saturation magnetization obtained is about 41.27emu/gm for Ni0.5Cu0.5Fe2O4 ferrite. © 2016 Elsevier B.V.

Neelgundmath M.,P.A. College | Neelgundmath M.,Karnataka Science College | Dinesh K.R.,Bangalore University | Mohan C.D.,University of Mysore | And 12 more authors.
Bioorganic and Medicinal Chemistry Letters | Year: 2015

Hepatocellular carcinoma (HCC) is the fifth most common malignant tumor worldwide, and is the third most common cause of cancer related death. Constitutive activation of NF-κB is the underlying mechanism behind tumorigenesis and this protein regulates the expression of genes involved in proliferation, survival, drug resistance, angiogenesis and metastasis. The design of inhibitors which suppress NF-κB activation is therefore of great therapeutic importance in the treatment of HCC. In this study, we investigated the effect of newly synthesized coumarin derivatives against HCC cells, and identified (7-Carbethoxyamino-2-oxo-2H-chromen-4-yl)methylpyrrolidine-1 carbodithioate (CPP) as lead compound. Further, we evaluated the effect of CPP on the DNA binding ability of NF-κB, CXCL12-induced cell migration and invasion, and the regulated gene products in HCC cells. We found that CPP induced cytotoxicity in three HCC cells in a time and dose dependent manner, and suppressed the DNA binding ability of NF-κB. CPP significantly decreased the CXCL12-induced cell migration and invasion. More evidently, CPP inhibits the expression of NF-κB targeted genes such as cyclin D1, Bcl-2, survivin, MMP12 and C-Myc. Furthermore, the molecular docking analysis suggested that CPP interacts with the p50 binding domain of the p65 subunit, scoring best among the 26 docked coumarin derivatives of this study. Thus, we are reporting CPP as a potent inhibitor of the pro-inflammatory pathway in Hepatocellular carcinoma. © 2014 Elsevier Ltd. All rights reserved.

Patil S.N.,NAVKIS PU Academy | Sanningannavar F.M.,Karnataka Science College | Navati B.S.,Karnataka Science College | Kusanur R.A.,Rashtreeya Vidyalaya College of Engineering | Melavanki R.M.,M.S. Ramaiah Institute of Technology
Canadian Journal of Physics | Year: 2014

The exited state (μe) dipole moment of a molecule is an important parameter, which gives information about electronic and geometrical structure of the molecule in the short-lived state. We have experimentally estimated the exited state (μe) dipole moment of two novel coumarin derivatives, namely, diethyl 2-acetamido-2-((6-methyl-2-oxo-2H-chromen-4-yl) methyl) malamute (DAM) and 5,6-Benzo-3-[1-(4,5-dicarbomethoxy-1,2,3-triazoloacetyl)] coumarin (5BDTC) by three methods, namely, Lippert's, Bakhshiev's, and Kawski-Chamma-Viallet's. In the Solvatochromic shift method, spectral shift is due to internal excitation of the molecule. We have recorded absorption and emission spectra of the above two novel coumarin derivatives at room temperature using solvents of different polarities. The geometry of the molecules were fully optimized and the ground state dipole moment (μg) were also calculated theoretically by Gaussian 03 software using B3LYP/6-31g∗ level of theory. The excited state dipole moment was calculated using CIS/6-31G∗ level of theory. The μg and μe were calculated using the solvatochromic shift method and μe was also determined in combination with μg. It was observed that μe were greater than those of μg, indicating a substantial redistribution of the π-electron densities in a more polar excited state for this coumarin. Further, the changes in dipole moment (Δμ) were calculated both from the solvatochromic shift method and on the basis of microscopic empirical solvent polarity (ETN) and the values are compared. © 2014 Published by NRC Research Press.

Chavan P.,Karnatak University | Naik L.R.,Karnatak University | Belavi P.B.,Gogte Institute of Technology | Chavan G.,Karnataka Science College | And 2 more authors.
Journal of Electronic Materials | Year: 2016

The semiconducting polycrystalline ferrite materials with the general formula Ni1−xMgxFe2O4 were synthesized by using the solid state reaction method. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectrographs, and atomic force microscopy techniques were utilized to study the structural parameters. XRD confirms the formation of single phase cubic spinel structure of the ferrites. The crystallite sizes of ferrites determined using the Debye–Scherer formula ranges from 0.963 μm to 1.069 μm. The cation distribution of ferrite shows that Mg2+ ions occupy a tetrahedral site (A-site) and the Ni2+ ion occupy an octahedral site (B-site) whereas Fe3+ ions occupies an octahedral as well as a tetrahedral site. The study of elastic parameters such as the longitudinal modulus, rigidity modulus, Young’s modulus, bulk modulus, and Debye temperature were estimated using the FTIR technique. The decrease of direct current (DC) resistivity with increase in temperature indicates the semiconducting nature of ferrites. The dielectric constant as well as loss tangent decreases with increase in frequency, and at still higher frequencies, they are almost constant. This shows usual dielectric dispersion behavior attributed to the Maxwell–Wagner type of interfacial polarization and is in accordance with Koop’s phenomenological theory. The linear increase of alternating current conductivity with increase of frequency shows the small polaron hopping type of conduction mechanism in all the ferrites. The magnetic properties such as saturation magnetization (Ms), magnetic moment, coercivity, remnant magnetization (Mr), and the ratio of Mr/Ms was estimated using the M–H loop. © 2016 The Minerals, Metals & Materials Society

Prashanth M.S.,Kuvempu University | David M.,Karnataka Science College
Bulletin of Environmental Contamination and Toxicology | Year: 2010

Activities of ATPase in different organs of Cirrhinus mrigala exposed to cypermethrin with lethal (5.13 μg/L) and sublethal (1.02 μg/L) concentration was investigated. Decrease of Na +-K +-ATPase activity was observed in gills, liver and muscle to about 60.22%, 22.13% and 48.89% respectively, by lethal concentration. Whereas in sublethal concentration activity was increased to about 7.84%, 10.70% and 5.96%. Similarly, in case of Mg 2+-ATPases activity as 57.61%, 48.82% and 28.59% for lethal and for sublethal it was 10.15%, 4.64% and 11.92%. Ca 2+-ATPase activity was observed to be 55.24%, 41.66% and 47.66% by lethal and for sublethal it was 8.02%, 24.89% and 6.47%. © 2009 Springer Science+Business Media, LLC.

Shettar A.K.,Karnatak University | Kotresha K.,Karnataka Science College | Kaliwal B.B.,Karnatak University | Vedamurthy A.B.,Karnatak University
Asian Pacific Journal of Tropical Disease | Year: 2015

Objective: To evaluate in vitro antioxidant and anti-inflammatory activity of Ximenia americana extracts. Methods: Herbal extraction was done by Soxhlet extraction method with increasing polarity of solvents viz., chloroform, ethyl acetate, methanol, ethanol and water. Phytochemical analysis was done using different biochemical tests. Antioxidant potential of plant extracts were analyzed by ferric ion reducing antioxidant power, phosphomolybdenum and 2,2-diphenyl-1-picrylhydrazyl, and anti-inflammatory activity by using protein denaturation in vitro bioassay. Total phenolic content of each extract was also determined to assess their corresponding effect on antioxidant capacity of plant. Results: Phytochemical analysis showed that each solvent extract contained broad spectrum of secondary metabolites, phenolic compounds, flavonoids, tannins and glycosides, whereas compared to other solvent extracts, chloroform extract showed negative result for phenolic compounds whereas aqueous extract exhibited the highest phenolic content and the significant antioxidant capacity based on the test performed. Out of all extracts, methanol extract showed high anti-inflammatory activity. Conclusions: The present study revealed that different solvent extracts of Ximenia americana leaves contain broad spectrum of bioactive compounds. Results confirm that aqueous extract exhibited high antioxidant activity and methanol extract exhibited high anti-inflammatory activity. Further study requires purification, characterization and structural elucidation of phenolic compounds in both extracts that may help in the development of new phytopharmaceuticals. © 2015 Asian Pacific Tropical Medicine Press.

Havanur V.C.,Karnatak University | Badiger D.S.,Karnatak University | Ligade S.G.,Karnataka Science College | Gudasi K.B.,Karnatak University
Der Pharma Chemica | Year: 2011

The heterocyclic ligand 2-anilino-N'-[(1E)-1-pyridin-2-ylethylidene]acetohydrazide (Apeah) was synthesized by coupling of 2-anilinoacetohydrazide with 2-acetylpyridine and characterized by IR, 1H and 13C-NMR spectra, it was then reacted with Lanthanide(III) nitrates to form complexes of the type [Ln(Apeah) 2 NO 3 H 2O]·2NO 3 where, Ln = La(III), Pr(III), Nd(III), Sm(III), Eu(III), Gd(III), Tb(III), Dy(III), Y(III). The metal complexes were characterized on the basis of elemental analysis, molar conductance, magnetic susceptibility measurements, TG/DTA and spectral (IR, 1H and 13C-NMR, UV-Visible and EPR) studies. The spectral data revealed that the Apeah behaves in tridentate fashion coordinating through carbonyl oxygen, azomethine nitrogen and pyridine nitrogen. The molar conductance values adequately supported their 1:2 electrolytic natures. Both Apeah and complexes were screened for their antimicrobial study. An enhancement of antimicrobial activity of the Apeah was observed on complexation.

Sannaningannavar F.M.,Karnataka Science College | Navati B.S.,Karnataka Science College | Ayachit N.H.,Alagappa Chettiar College of Engineering And Technology
Journal of Applied Polymer Science | Year: 2012

Thermodynamic parameters, like change in free energy of activation (ΔG τ *), enthalpy of activation (ΔH τ *), and entropy of activation (ΔS τ *) of poly(ethylene glycol) with average molecular mass 400 Delton (PEG 400) in dilute solution of benzene were computed on the basis of theory of Eyring rate process. To estimate these, the dielectric relaxation time (τ), determined at various temperatures adopting Whiffen and Thompson model have been used. X-band microwave bench working at 9.59 GHz was employed to find temperature dependent real part ε of the complex dielectric permittivity ε* and dielectric loss ε″. The values of these ε and ε″ are used to find τ values. Based on the results reported, the relaxation behavior of the stated polymer in nonpolar solvent is discussed. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 Copyright © 2012 Wiley Periodicals, Inc.

Sunil Kumar R.K.,University of Mysore | Suresh Kumar B.V.,University of Mysore | Manjunatha S.,Karnataka Science College
Nature Environment and Pollution Technology | Year: 2012

Assessment of surface and groundwater quality has been carried out in the parts of the Sandur schist belt, Bellary district, Karnataka, South India. Sandur schist belt is well known for iron ore deposits. Rigorous and unplanned mining methods causes intensive natural hazards like water pollution, air pollution, noise pollution, dust pollution, etc. Water quality of the study area has been studied for sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), chloride (Cl), fluoride (F), sulphate (SO 4), nitrate (NO 3) and total hardness. Results show gradual decrease in groundwater quality and surface water pollution in and around the parts of Sandur Schist belt. Mapping of re-vegetation site selection at regional scales is essential for a wide range of applications including landslide, erosion, land planning, global warming, LU/LC alterations (especially on human activities), effect of climate, natural hazard and socio-economic dynamics in global and local scale. In this study, re-vegetation site selection has been carried out by using remote sensing and Geographic Information System (GIS) in Sandur schist belt in Bellary District. Identification potential sites for replantation within the mining pit is a complicated thing using change detection comparison (pixel by pixel).

Dodamani A.F.,Karnataka Science College
Research Journal of Pharmaceutical, Biological and Chemical Sciences | Year: 2012

The study of the adduct formation of Ni(Il) di(3-chloro,2-methylphenyl) carbazonate has been undertaken by synthesising and characterizing it by magnetic susceptibility, UV-VIS, IR and 'H-NMR spectral measurements. The distorted square planar Ni(TT) chelate forms adducts with heterocyclic nitrogen bases; spectrophotometric method has been employed for the study of the adduct formation in a monophase chloroform. Both bidentate and unsaturated monodentate heteronuclear nitrogen bases form hexacoordinated adducts with 1:1 and 1:2 stoichiometry, respectively (metalchelate:base). However, the saturated nitrogen bases form pentacoordinated adducts with 1:1 stoichiometry. The results are discussed in terms of basicity and steric factors of the bases.

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