Publications by authors named "Sharmistha Das"

, an opportunistic pathogen often causes biofilm-linked infections. A combinatorial approach involving tetracycline (antibiotic) and cuminaldehyde (phytochemical) was explored to combat this infectious pathogen. The results showed that both tetracycline and cuminaldehyde individually demonstrated antibacterial effects.

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The doping of CdS quantum dots (QDs) with Cu(I) disrupts electron-hole correlation due to hole trapping by the dopant ion, post-photoexcitation. The present paper examines the effect of such disruption on the rate of photoinduced electron transfer (PET) from the QDs to methyl viologen (MV2+), with implications in their photocatalytic activity. A significantly greater efficiency of PL quenching by MV2+ is observed for the doped QDs than for the undoped ones.

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Staphylococcus aureus, an opportunistic Gram-positive pathogen, is known for causing various infections in humans, primarily by forming biofilms. The biofilm-induced antibiotic resistance has been considered a significant medical threat. Combinatorial therapy has been considered a reliable approach to combat antibiotic resistance by using multiple antimicrobial agents simultaneously, targeting bacteria through different mechanisms of action.

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Pseudomonas aeruginosa is widely associated with biofilm-mediated antibiotic resistant chronic and acute infections which constitute a persistent healthcare challenges. Addressing this threat requires exploration of novel therapeutic strategies involving the combination of natural compounds and conventional antibiotics. Hence, our study has focused on two compounds; cuminaldehyde and ciprofloxacin, which were strategically combined to target the biofilm challenge of P.

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Methicillin-resistant Staphylococcus aureus (MRSA), a drug-resistant human pathogen causes several nosocomial as well as community-acquired infections involving biofilm machinery. Hence, it has gained a wide interest within the scientific community to impede biofilm-induced MRSA-associated health complications. The current study focuses on the utilization of a natural bioactive compound called piperine to control the biofilm development of MRSA.

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The emergence of biofilm-induced drug tolerance poses a critical challenge to public healthcare management. Pseudomonas aeruginosa, a gram-negative opportunistic bacterium, is involved in various biofilm-associated infections in human hosts. Towards this direction, in the present study, a combinatorial approach has been explored as it is a demonstrably effective strategy for managing microbial infections.

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Staphylococcus aureus causes a range of chronic infections in humans by exploiting its biofilm machinery and drug-tolerance property. Although several strategies have been proposed to eradicate biofilm-linked issues, here, we have explored whether piperine, a bioactive plant alkaloid, can disintegrate an already existing Staphylococcal biofilm. Towards this direction, the cells of S.

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1, 4-naphthoquinone, a plant-based quinone derivative, has gained much attention for its effectiveness against several biofilm-linked diseases. The biofilm inhibitory effect of 1, 4-naphthoquinone against Staphylococcus aureus has already been reported in our previous study. We observed that the extracellular DNA (eDNA) could play an important role in holding the structural integrity of the biofilm.

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Microorganisms embedded within an extracellular polymeric matrix are known as biofilm. The extensive use of antibiotics to overcome the biofilm-linked challenges has led to the emergence of multidrug-resistant strains. Staphylococcus aureus is one such nosocomial pathogen that is known to cause biofilm-linked infections.

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A green, novel and eco-efficient synthetic route towards the synthesis of highly substituted bio-active pyrrolidine-2-one derivatives was demonstrated using β-cyclodextrin, a water-soluble supramolecular solid as a green and eco-benign catalyst at room temperature under water-ethanol solvent medium. The exploration of the green catalyst β-cyclodextrin for the metal-free one-pot three-component synthesis of a wide range of highly functionalized bio-active heterocyclic pyrrolidine-2-one moieties from easily available aldehydes and amines explains the superiority and uniqueness of this protocol.

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Cu-doped CdS quantum dots (QDs) have been synthesized in water using 3-mercaptopropionic acid (3-MPA) as the capping agent. They exhibit intense photoluminescence and excellent color tunability, unlike most of the QDs synthesized/dispersed in water so far. Complete characterization of these aqueous doped CdS QDs has been performed for the first time, along with a single particle level elucidation of their exciton dynamics using fluorescence correlation spectroscopy.

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Gram-positive and Gram-negative bacteria often develop biofilm through different mechanisms in promoting pathogenicity. Hence, the antibiofilm molecule needs to be examined separately on both organisms to manage the biofilm threat. Since the antibiofilm activity of piperine against Staphylococcus aureus was already reported; here, we aimed to examine the antibiofilm activity of it against Pseudomonas aeruginosa.

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Soil erosion coupled with high runoff poses a significant threat to the topsoil fertility, declining its productivity and raising major environmental and socio-economic issues such as land degradation, desertification, food scarcity, and hunger globally. Several conservation methods have been widely adopted in order to reduce runoff and protect the soil from erosion. The effectiveness of such conservation practices are controlled by many factors (i.

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Pseudomonas aeruginosa, an opportunistic pathogen, has been found to cause several chronic and acute infections in human. Moreover, it often shows drug-tolerance and poses a severe threat to public healthcare through biofilm formation. In this scenario, two molecules, namely, cuminaldehyde and tobramycin, were used separately and in combination for the efficient management of biofilm challenge.

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3-Aminoquinoline (3AQ) has been used as a fluorescent probe for preferential solvation in hexane-ethanol solvent mixtures. Results of the present experiment have been put into context by comparison with prior observations with 5-aminoquinoline (5AQ) as the probe. 3AQ exhibits a relatively small change of dipole moment (Δ= 2.

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Rechargeable magnesium-sulfur (Mg-S) batteries offer the potential for inexpensive energy storage alternatives to other metal-ion batteries for the grid scale and household applications. Despite all economic and resource advantages, Mg-S battery chemistry suffers from a complicated reaction mechanism and extremely slow reaction kinetics. To improve the kinetics, we improvise a new electrode architecture where a conductive polymer is used along with a carbon network.

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Staphylococcus aureus causes numerous community-acquired and nosocomial infections in humans by exploiting biofilm. In this context, this study aims to impede the formation of Staphylococcus aureus biofilm by exposing the cells to a plant-based alkaloid, piperine. Our study revealed that piperine exhibited considerable antimicrobial activity against the test organism.

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Considering the current threatening conditions of climate change, Climate Smart Agriculture (CSA) aims to improve the soil health and its organic carbon stocks by encouraging soil carbon sequestration through conservation practices in agricultural lands. However, the effects of these practices differ due to diverse climatic scenario, soil characteristics and management system. To identify the suitable practices that can be effective under tropical and subtropical conditions, a systematic evaluation in the form of a meta-analysis of these practices and their outcomes was performed over those regions.

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often causes various acute and chronic infections in humans exploiting biofilm. Molecules interfering with microbial biofilm formation could be explored for the sustainable management of infections linked to biofilm. Towards this direction, the antimicrobial and antibiofilm activity of cuminaldehyde, an active ingredient of the essential oil of was tested against .

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5-Aminoquinoline (5AQ) has been used as a fluorescent probe of preferential solvation (PS) in binary solvent mixtures in which the nonpolar component is diethyl ether and the polar component is protic (methanol) or aprotic (acetonitrile). Hence, the roles of solvent polarity and solute-solvent hydrogen bonding have been delineated. Positive deviations of spectral shifts from a linear dependence on the concentration of the polar component, signifying PS, are markedly more pronounced in case of the protic solvent.

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Strategies have been explored for developing strongly fluorescent species out of a weakly fluorescent Schiff base, 2-(((pyridin-2-ylmethyl)imino)methyl)phenol (salampy). The locally excited enolic state of salampy undergoes an intramolecular proton transfer with a time constant of 200 fs. The emissive cis keto state thus formed decays completely within 50 ps.

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Brightly photoluminescent Cu-doped CdSe nanotetrapods (NTPs) have been prepared by a modified hot injection method. Their photoluminescence (PL) has a quantum yield of 38% and decays slowly over a few microseconds, while the PL in undoped NTPs has a rather small quantum yield of 1.7% and decays predominantly in tens of picoseconds, with a minor component in the nanosecond time regime.

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Staphylococcus aureus causes several nosocomial and community-acquired infections in human host involving biofilm. Thus, strategies need to be explored to curb biofilm threats by either inhibiting the formation of biofilm or disintegrating the pre-existing biofilm. Towards this direction, we had already revealed the biofilm inhibiting properties of 1,4-naphthoquinone against S.

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Breast cancer is the second leading cause of cancer deaths in women with significant morbidity and mortality. Present study describes design, synthesis and detailed pharmacology of indole derivatives exhibiting remarkable broad spectrum antiproliferative activity against breast cancer cells. Detailed mechanistic evaluations confirmed induction of G0/G1 arrest, apoptosis induction, loss of mitochondrial integrity, enhanced ROS generation, autophagy, estrogen receptor β-transactivation and increased tubulin polymerization.

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Drug discovery is moving at a rapid pace and a fast turnaround of bioanalytical data is needed to sustain this pace. This article focuses on the evaluation of time-saving homogeneous proximity immunoassays such as Amplified Luminescent Proximity Homogeneous Assay, Time-Resolved Fluorescence Resonance Energy Transfer and Spatial Proximity Analyte Reagent Capture Luminescence as an alternative to industry popular platforms like mesoscale discovery (MSD) and Gyrolab. Our evaluation showed that no one platform can be considered the best for all the parameters assessed.

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