Binding of Nile Blue (NB) with calf thymus DNA has been studied using molecular modeling, spectroscopic, and thermodynamic techniques. Our study revealed that NB binds to the DNA helix by two types of modes (groove binding and intercalation) simultaneously. The thermodynamic study showed that the overall binding free energy is a combination of several negative and positive free energy changes. The binding was favored by negative enthalpy and positive entropy changes (due to the release of water from the DNA helix). The docking study validated all experimental evidence and showed that NB binds to a DNA minor groove at low concentrations and switches to intercalation mode at higher concentrations.

The present work investigates the hydrochemical properties of the surface and groundwater of the Mayurakshi River Basin (India) for assessing their irrigation suitability with respect to irrigation hazards. The study involves 72 water samples classified as 48 surface water samples (pre-monsoon: 24; post-monsoon: 24) and 24 groundwater samples (pre-monsoon:12; post-monsoon: 12). Regarding the specific irrigation hazard, percent of sodium and soluble sodium percentage have demonstrated the groundwater vulnerability to sodium while the surface water is observed to be free from this kind of hazard. Similar findings have also been retained for magnesium hazard and the potential salinity hazard. Moreover, regarding the seasonality of the hazards, the post-monsoon season has depicted a higher level of irrigation hazards compared to the pre-monsoon season. The study found that the general evolution of groundwater hydrochemistry and the suitability of water for irrigation are principally governed by carbonate weathering, sand mining, stone crushing, and the development of brick kiln industries. Our methodology can be a good example for similar contexts, especially in developing and tropical countries.

Two phytochemicals, thymol and thymoquinone obtained from thymes (Thymus vulgaris L., Lamiaceae etc.) and Nagila Sativa seed, respectively. Both the phytochemicals show several biochemical activities like anticancer, antimicrobial etc. In this paper, we studied the affinities of thymol and thymoquinone towards calf thymus DNA (CT-DNA) and protein (bovine serum albumin). Spectroscopic and molecular modelling studies revealed that both compounds have a high affinity toward both the receptors; DNA and protein. Both phytochemicals binds to the minor grooves of DNA and suitable pockets of protein. Several free energy function and hydrogen bonding play significant role during the binding phenomenon. Communicated by Ramaswamy H. Sarma

Environmental pollution poses a major problem now a day. Several dyes, in the form of industrial waste, pollute water body and may cause adverse effects to human health. In this paper ADME and toxicity of fives Phenothiazinium group of dyes Methylene blue (MB), Azure A (AA), Azure B (AB), Azure C (AC) and Toluidine Blue O (TBO) were predicted using Swiss ADME and Protox II tools. Results showed these dyes may herm for living organism due to their carcinogenic, mutagenic and hepatotoxic properties. Removal efficiency of these dyes using okra plant product were determined using spectroscopic, thermodynamic and molecular modeling study. It was revealed that these dyes adsorb on the surface of okra leaf mostly at pH 7.0 and the adsorption isotherms were found to fit in Langmuir and Freundlich isotherm model, while Temkin model fails to do this. Mucilage present in different parts of okra plant plays a significant role on removal of these dyes and is able to remove near about 71-92 % of dyes from water body by itself. As this process did not fit in any of above said adsorption isotherm model, it may be suggested that some other mechanism may happen. Further studies explore that these dyes bound to the hydrophobic pocket of mucilage with binding affinity in the order of 105 M- 1 and the bindings were exothermic in nature with enthalpy change in the range of - 2.94 to - 4.28 kcal/mole. Molecular docking study validate all the experimental results obtained from spectroscopic and thermodynamic study and enlighten the role of structure of dyes on their binding affinity to mucilage. This paper will help to systematically understand the role of okra plant products on removal efficiency of Phenothiazinium group of dyes with their structural variations.

Lawsone (2-hydroxy-1,4-naphthoquinone), also known as hennotannic acid, is a red-orange dye present in the leaves of the henna plant (Lawsonia inermis) having lots of biological activities. In this paper, we have investigated the structural basis of binding affinities of Lawsone towards two different targets namely, calf thymus DNA (CT-DNA) and protein bovine serum albumin (BSA) using experimental and computational approaches. This phytochemical binds to the minor groove of DNA and Sudlow site II, Domain III of BSA. The binding constants obtained from spectroscopic studies for Lawsone with DNA and BSA have been determined as 1.79 × 10³ M^-1 and 2.18 × 10³ M^-1, respectively with corresponding Gibbs free energies of -4.46 kcal/mol and -4.58 kcal/mol. Conformational changes in the secondary structures of the receptors upon binding with Lawsone is observed. Isothermal titration calorimetry (ITC) experiments reveal that binding is favoured mainly due to negative enthalpy changes (-18.2 kcal/mol for DNA and -98.77 kcal/mol for BSA). Molecular docking and dynamics simulations elucidate intermolecular contacts between Lawsone and the receptors, providing insight into the energetic profile of the complexes and revealing Lawsone's reorientation within the binding sites. Both experimental and computational findings highlight the significance of hydrogen bonding and hydrophobic interactions in the binding process, offering valuable insights into Lawsone's molecular interactions with biomolecules and its potential therapeutic applications.