Darrang College

Tezpur, India

Darrang College

Tezpur, India
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Ghosal A.,Darrang College | Tamuli P.,Darrang College
Plant Archives | Year: 2017

The medicinal plants are using for treating various infectious diseases and has been used by the majority of the world's population for thousands of years. Human infections caused by various micro-organisms such as bacteria and fungi constitute a very serious problem. The ear, nose and throat are the vital organs of the body and they are interconnected to each other. For healthy body, maintaining the health is utmost important. Thus, the study and documenting of traditional ethno medicines practiced by various ethnic groups is essential. The ethnomedicinal plants which are used to treat ear, nose and throat diseases are safe, effective and inexpensive, for which there is a global trend for the revival of traditional herbal medicine. A review was made to explore some important ethnomedicinal plants used by healers of different ethnic groups of world to cure ENT diseases. A total of 51 plant species along with their uses have been discussed.

Dutta A.,Tezpur University | Boruah B.,Tezpur University | Manna A.K.,Jawaharlal Nehru Centre for Advanced Scientific Research | Gohain B.,Tezpur University | And 2 more authors.
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2013

A newly observed UV band of aqueous curcumin, a biologically important molecule, in presence of anionic surfactants, viz., sodium dodecylsulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), and sodium dodecylsulfonate (SDSN) in buffered aqueous solutions has been studied experimentally and theoretically. The 425 nm absorption band of curcumin disappears and a new UV-band is observed at 355 nm on addition of the surfactants in the submicellar concentration range which is reversed as the surfactant concentration approaches the critical micelle concentration (CMC). The observed spectral absorption, fluorescence intensity and surface tension behavior, under optimal experimental conditions of submicellar concentration ranges of the surfactants in the pH range of 2.00-7.00, indicate that the new band is due to the β-diketo tautomer of curcumin stabilized by interactions between curcumin and the anionic surfactants. The stabilization of the diketo tautomer by submicellar anionic surfactants described here as well as by submicellar cationic surfactant, reported recently, is unique as this is the only such behavior observed in presence of submicellar surfactants of both charge types. The experimental results are in good agreement with the theoretical calculations using ab initio density functional theory combined with time dependent density functional theory (TD-DFT) calculations. © 2012 Elsevier B.V. All rights reserved.

Tamuli P.,Darrang College | Sharma P.,Haflong Government College
Indian Journal of Traditional Knowledge | Year: 2010

Folklore medicinal uses of 25 plant species belonging to 23 families for various ailments among the Dimasa Kacharis, one of the prominent ethnic tribes of North Kachar Hills district of Assam is reported. The study was undertaken covering the area of Dimasa inhabiting villages of NC Hills district of Assam.

Dutta A.,Tezpur University | Boruah B.,Tezpur University | Saikia P.M.,Darrang College | Dutta R.K.,Tezpur University
Journal of Molecular Liquids | Year: 2013

The interaction of aqueous curcumin with cationic surfactants of varying chain lengths and head group, stabilizing its β-diketo tautomer and exhibiting an UV band around 355 nm, has been studied in buffered aqueous solutions in the pH range of 2.00-7.00 by UV-visible and fluorescence spectroscopy, and surface tensiometry under optimal experimental conditions of submicellar concentration of the surfactants. Time Dependent Density Functional Theory (TD-DFT) has also been used to predict the molecular structure and excitation energies of the interaction product in the ground state and the nature of the interaction. As the surfactant concentration increases, the curcumin-cationic complex forms premicellar aggregates where the curcumin exists in a highly polar microenvironment before shifting its location to the nonpolar core of the surfactant micelles. The strength of the interaction increases with the chain length of the surfactant and also changes on changing the head group of the surfactant. An observed secondary salt effect on the interaction indicates an unusual involvement of a proton in the interaction. Based on the experimental and theoretical evidences the following mechanism has been proposed for the stabilization of the β-diketo form: on the approach of the cationic surfactant, a protonation of the methylenic central carbon atom of curcumin takes place simultaneously breaking the π-conjugation and facilitating the detachment of the enolic proton paving the way for an ion dipole binding between the cationic head group and the electron-rich β-diketo oxygen atoms. Hydrophobic interaction between the tail of the surfactant and the nonionic curcumin molecule assists the electrostatic interaction. © 2013 Elsevier B.V.

Satapathy S.S.,Tezpur University | Powdel B.R.,Darrang College | Dutta M.,Tezpur University | Buragohain A.K.,Tezpur University | And 2 more authors.
Journal of Molecular Evolution | Year: 2014

The fourfold degenerate site (FDS) in coding sequences is important for studying the effect of any selection pressure on codon usage bias (CUB) because nucleotide substitution per se is not under any such pressure at the site due to the unaltered amino acid sequence in a protein. We estimated the frequency variation of nucleotides at the FDS across the eight family boxes (FBs) defined as Um(g), the unevenness measure of a gene g. The study was made in 545 species of bacteria. In many bacteria, the Um(g) correlated strongly with Nc′ - a measure of the CUB. Analysis of the strongly correlated bacteria revealed that the U-ending codons (GGU, CGU) were preferred to the G-ending codons (GGG, CGG) in Gly and Arg FBs even in the genomes with G+C % higher than 65.0. Further evidence suggested that these codons can be used as a good indicator of selection pressure on CUB in genomes with higher G+C %. © 2013 Springer Science+Business Media New York.

Boruah B.,Tezpur University | Saikia P.M.,Darrang College | Gohain B.,Tezpur University | Dutta R.K.,Tezpur University
Journal of Molecular Liquids | Year: 2010

Acid-base equilibrium of phenol red (PR), a sulphonephthalein dye, was studied spectrophotometrically in aqueous media containing water soluble nonionic polymers viz., polyvinyl alcohol (PVA) and polyethylene glycol (PEG) in the presence of an anionic surfactant, sodium dodecyl sulfate (SDS). A partition equilibrium method was utilized to determine the equilibrium constant of partition of the PR between micellar pseudo phase and aqueous phase and the critical aggregation concentration (CAC) of SDS in buffered aqueous systems containing the neutral polymers. The pH dependent association constants, Kass of PR with SDS-PVA, and SDS-PEG system increase in the order PEG 200 < PEG 400 < PEG 600 < PVA. The value of Kass was found to be greater in Tris buffer system than in phosphate buffer system of same pH. Interaction of the dye with the aqueous SDS-PVA and SDS-PEG systems is found to be endothermic and entropy oriented. © 2009 Elsevier B.V. All rights reserved.

Gohain B.,Tezpur University | Boruah B.,Tezpur University | Saikia P.M.,Darrang College | Dutta R.K.,Tezpur University
Journal of Physical Organic Chemistry | Year: 2010

The premicellar and micelle formation behaviors of four cationic triphenylmethane dyes, viz, Pararosaniline (RN), Crystal violet (CV), Ethyl violet (EV), and Malachite green (MG), in aqueous anionic surfactant solutions of sodium dodecyl sulfate (SDS), sodium dodecyl benzene sulfonate (SDBS), and sodium dodecyl sulfonate (SDSN) have been studied by spectral and surface tension measurements. The study was carried out within a pH range where the dyes are stable in their quinoid forms. The dyes have been found to form dye-surfactant ion pairs (DSIPs) with the surfactants, at the surfactant concentrations well below their critical micelle concentration, CMC*. The DSIPs behave like nonionic surfactants and form an air-water interfacial monolayer. The DSIPs have a lower critical micelle concentration (CMC IP), greater efficiency, and lower effectiveness than the corresponding pure surfactants. As the surfactant concentration is increased below the CMC*, the DSIPs start forming micelles of their own where the dye gets protonated and exists as a protonated dye-surfactant ion pair (PDSIP) in the ion pair micelles. As the concentration of the surfactant exceeds the CMC* of the pure surfactant, the protonation reverses gradually with the dye remaining in the micelles in solubilized form and the DSIPs in the air-water interfacial monolayer are replaced by pure surfactants. The distorted helical isomeric form (isomer B) of the dyes is favored in the PDSIPs. Copyright © 2009 John Wiley & Sons, Ltd.

Boruah B.,Tezpur University | Saikia P.M.,Darrang College | Dutta R.K.,Tezpur University
Journal of Photochemistry and Photobiology A: Chemistry | Year: 2012

The effect of the biopolymer chitosan, in presence of a cationic surfactant, viz., cetyl trimethyl ammonium bromide (CTAB) and a non-ionic surfactant, viz., polyoxyethylene (20) sorbitan monooleate (TW80) on the solubility and spectroscopic properties of the bioactive compound curcumin has been studied at physiological pH (7.4) condition. Based on the solvent and medium sensitive absorption and fluorescence properties of curcumin, the apparent binding constants of curcumin to chitosan, chitosan-CTAB and chitosan-Tween-80 systems have been estimated. From the fluorescence quenching by potassium iodide and acrylamide of the chitosan entrapped curcumin solutions, it has been found that curcumin is non-uniformly distributed in the colloidal chitosan solution. Curcumin is located mostly inside the hydrophobic interior of chitosan while a small fraction resides in the cationic centres of chitosan. The stability provided to curcumin by chitosan alone and in the presence of CTAB and TW80 has been investigated by spectrophotometric analysis of the kinetics of degradation of curcumin. It has been observed that the reaction rate constants were decreased in various systems in the order: chiotsan-TW80 > chitosan-CTAB > chitosan. The interaction of curcumin with chitosan has been found to be exothermic and driven by hydrophobic interactions, hydrogen bond formation, and electrostatic interactions. © 2012 Elsevier B.V. All rights reserved.

Boruah B.,Tezpur University | Saikia P.M.,Darrang College | Dutta R.K.,Tezpur University
Dyes and Pigments | Year: 2010

The monomer-dimer process of C.I. Basic Blue in an aq. solution of the anionic surfactant, sodium dodecyl sulfate and the nonionic polymer, polyvinyl alcohol, was investigated spectrophotometrically. The effective dimerization constant of the dye (effKD) was determined in the presence of the surfactant and polymer, both individually and in combination, from a low ionic strength buffered aq solution; the value of effKD increased in the order: PVA < SDS < PVA-SDS < H 2O. Aggregation of the dye in the polymer-surfactant system was exothermic and displayed large negative ΔHo and negative ΔSo values. Below the CAC, the presence of surfactant facilitated dye dimerization whereas > CAC the dye dissolved monomerically in the surfactant/polymer complex; the monomer-dimer process of the dye was influenced by hydrophobic interactions. © 2009 Elsevier Ltd. All rights reserved.

PubMed | Tezpur University and Darrang College
Type: | Journal: DNA research : an international journal for rapid publication of reports on genes and genomes | Year: 2016

The different triplets encoding the same amino acid, termed as synonymous codons, are not equally abundant in a genome. Factors such as G+C% and tRNA are known to influence their abundance in a genome. However, the order of the nucleotide in each codon per se might also be another factor impacting on its abundance values. Of the synonymous codons for specific amino acids, some are preferentially used in the high expression genes that are referred to as the optimal codons (OCs). In this study, we compared OCs of the 18 amino acids in 221 species of bacteria. It is observed that there is amino acid specific influence for the selection of OCs. There is also influence of phylogeny in the choice of OCs for some amino acids such as Glu, Gln, Lys and Leu. The phenomenon of codon bias is also supported by the comparative studies of the abundance values of the synonymous codons with same G+C. It is likely that the order of the nucleotides in the triplet codon is also perhaps involved in the phenomenon of codon usage bias in organisms.

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