On binding mechanism exploration of organic amphoteric dye Rhodamine B with natural polymeric DNA

Abstract Nucleic acids, like DNA and RNA, are molecules that are present in any life form. Their most notable function is to encode biological information. DNA also has unique material properties, which attract material scientists, nanotechnologists, and engineers. The study and investigation of the structural and dynamical properties of complex biological systems have attracted considerable interest among scientists in general and physicists and biologists in particular.The alteration in DNA due to the introduction of any small molecule changes the overall function and stability of DNA. So quantitative information about the effects of such ligand binding on the structure and function of DNAs, are very much required. In this study, the interaction between natural polymeric DNA (deoxyribonucleic acid sodium salt from herring testes; derived from the sperm of herring fish) and organic amphoteric dye molecule (fluorescent, biomarker), Rhodamine B, has been studied quantitatively. An overview of the overall changes occurring in the macromolecule was estimated using multi-spectroscopic methods and complemented with computational analyses. The results obtained provide an understanding of the binding affinity, stoichiometry, and structural details of the ligand-DNA complex, followed by an estimation of associated binding thermodynamics. Finally, structure–function relationships and molecular aspects of ligand binding to DNA have been established in the current piece of research work, which can have multifaceted applications in drug development and pharmacology

Binding effects of antibiotic drug sulfamethazine on the serum albumins: Multi-spectroscopic and computation approach

Over the past decades, bio-macromolecules-drug binding interaction studies have been of great interest with varied applications in drug modification and development. Such reports help us to recognize the molecular aspects of the bindings correlating with the structural phenomenon. The binding study of an antibiotic drug, Sulfamethazine (SMZ) with plasma proteins, Human Serum Albumin (HSA), and Bovine Serum Albumin (BSA) have been investigated using spectroscopic and computational techniques. The UV–Vis and fluorescence spectroscopic data indicate towards potential binding affinity of the drug to the proteins through the formation of stable ground state complexes. Binding constants obtained were in the order of 104 M − 1 for both the cases, the values were comparatively higher for HSA than BSA. Thermodynamic parameters were estimated from temperature-dependent fluorescence analyses; enthalpy driven, exothermic nature of the binding interactions along with the predominance of electrostatic and hydrophobic forces were established in both the cases. Synchronous fluorescence and FT-IR spectra revealed the conformational changes in the protein structure(s). Molecular docking and dynamic studies further supported the complex formation in accordance with the experimental report(s). Molecular docking denoted binding of the drug at pocket-I of the active site in proteins, while molecular dynamic simulation established the stability and compactness of the complex due to binding

On the traditional medicinal plants and plant derived natural drugs used by indigenous people of Nagaland, India

An ethnobotanical documentation on the medicinal plants used by local people of Nagaland, (North-east India) has been presented here. The study explored 33 plant species (with their local names, indigenous applications, sources/origins, parts of plants used, bioactive compounds present, process of preparing medicines from the plants) belonging to 28 families have been reviewed thoroughly. Some examples are, Catharanthus roseus (Tsuinrinaro, Periwinkle), Acacia pennata (Chakrangaing, Ballikhadira), Adhatoda vasica (Kicharangnaro, Malabar-nut), Ageratum conzyoides (Imchenriza, Billy-goat-weed, /Tropical-white-weed), Alstonia scholaris (Lazarongpang, Blackboard), Rauvolfia serpentina (Per-mozutong, Indian-snakeroot) etc. Plant based drugs are very popular and effective in Nagaland from ancient times but thorough-documentation with scientific-background of effectiveness, active chemical-compounds present, their action-mechanism etc. are still scanty. Such review can be of useful for pharmacologist, phyto-chemists to a broad group of researchers and may lead to discovery of new sources of novel medicines through traditional therapeutic knowledge

On the traditional medicinal plants and plant-derived natural drugs used by indigenous people of Nagaland, India

An ethnobotanical documentation on the medicinal plants used by local people of Nagaland (North-east India) has been presented here. The study explored 33 plant species (with their local names, indigenous applications, sources/origins, parts of plants used, bioactive compounds present, process of preparing medicines from the plants) belonging to 28 families have been reviewed thoroughly. Some examples are, Catharanthus roseus (Tsuinrinaro, Periwinkle), Acacia pennata (Chakrangaing, Ballikhadira), Adhatoda vasica (Kicharangnaro, Malabar-nut), Ageratum conzyoides (Imchenriza, Billy-goat-weed,/Tropical-white-weed), Alstonia scholaris (Lazarongpang, Blackboard), Rauvolfia serpentina (Per-mozutong, Indian-snakeroot), etc. Plant based drugs are very popular and effective in Nagaland from ancient times but thorough-documentation with scientific-background of effectiveness, active chemical-compounds present, their action-mechanism, etc., are still scanty. Such review can be of useful for pharmacologist, phyto-chemists to a broad group of researchers and may lead to discovery of new sources of novel medicines through traditional therapeutic knowledge.</p

Thermodynamic Investigations of Ligand–Protein Interactions: Binding of the Phenazinium Dyes Phenosafranin and Safranin O with Human Serum Albumin

The binding of the phenazinium dyes, phenosafranin (PSF) and safranin O (SO) with human serum albumin was investigated by calorimetry and spectroscopic techniques. Binding parameters revealed that PSF has a higher affinity (K = 1.60 � 105 M�1) compared to SO (K = 0.97 � 105 M�1). The binding of both dyeswas favoured by negative enthalpy and a stronger favourable entropy contribution. The heat capacity values were similar indicating the involvement of similar hydrophobic forces in the complexation. Enthalpyentropy compensation was also observed for both dyes. Both polyelectrolytic and non-polyelectrolytic forces contributed towards the binding but the later was dominant. The fluorescence data suggested a static quenching mechanism. Forster resonance energy transfer studies showed that the specific binding distances between Trp (donor) residue of the protein and the dye (acceptor) molecules were 3.95 and 4.07 nm, respectively, for PSF and SO. Both dyes bind to same site, viz. site I (subdomain II A) of HSA but SO having bulkier groups binds weakly due to steric hindranc

Assessment of water safety and associated health risks of Nagaland’s capital, Kohima: A physico-chemical and statistical investigation

Access to quality drinking water is a must for every individual however with increasing urbanization and development, water pollution has been on the rise in the past decades. This study aims to assess the drinking water quality collected from the capital city of Nagaland, India and analyzes the parameters that may be responsible for water contamination. Collected water samples were analyzed using Statistical analysis and the Water Quality Index concerning thirteen parameters namely pH, temperature, TDS, EC, DO, TH, Ni, Al, SO^_4, PO^_4, Ca, Mg, and TOC. As per the analysis, all the parameters were under the permissible limits as suggested by the BIS. The major concern is the high concentration of Aluminium which poses a risk for causing Alzheimer’s disease. Hence such research is crucial to formulate designs for prospective water management which is possible only by obtaining detailed data of the water condition for the concerned areas

Mechanistic studies on the oxidation of pyruvic acid by an oxo-bridged diiron(III,III) complex in aqueous acidic media

In aqueous solution [Fe2(μ-O)(phen)4(H2O)2]4+ (1, phen = 1,10-phenanthroline) equilibrates with its conjugate bases [Fe2(μ-O)(phen)4(H2O)(OH)]3+ (2) and [Fe2(μ-O)(phen)4(OH)2]2+ (3). In the presence of excess phen and in the pH range 2.5-5.5, the dimer quantitatively oxidizes pyruvic acid to acetic acid and carbon dioxide, the end iron species being ferroin, [Fe(phen)3]2+. The observed reaction rate shows a bell-shaped curve as pH increases, but is independent of added phen. Kinetic analysis shows that (3) is non-reactive and (1) has much higher reactivity than (2) in oxidizing pyruvic acid. The basicity of the bridging oxygen increases with deprotonation of the aqua ligands. The reaction rate decreases significantly in media enriched with D2O in comparison to that in H2O, with a greater retardation at higher pH, suggesting the occurrence of proton coupled electron transfer (PCET; 1e, 1H+), which possibly drags the energetically unfavorable reaction to completion in presence of excess phen. © 2009 Elsevier Ltd. All rights reserved