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511.
Govindasamy Balasubramani Paramasivam Deepak Rajamani Sowmiya Rajendiran Ramkumar 《Natural product research》2015,29(10):958-960
This study pertains to the phytochemical components and the biological properties of the weed, Antigonon leptopus Hook. & Arn. (AUT/PUS/064). Phytochemical screening of methanolic leaf extract of A. leptopus revealed the presence of saponin, phenolic compounds, tannins, flavonoids, alkaloids, fixed oils and amino acids. Accordingly, 12 phytochemical components were analysed and characterised by GC–MS. Antibacterial activity was evaluated against fish and clinical pathogens. Fish pathogens, Providencia vermicola (MTCC 5578) and Aeromonas hydrophila (MTCC 646) were more sensitive to the methanolic leaf extract than clinical pathogens. A useful information was obtained from the phytochemistry of A. leptopus leaves, which would pave way to further applications to treat fish diseases and for utility in the pharmaceutical field. 相似文献
512.
Arpitha Badarinath Mahajanakatti Telugu Seetharam Deepak Raghu Ram Achar Sushma Pradeep Shashanka K Prasad Rajeswari Narayanappa Deepthi Bhaskar Sushravya Shetty Govindappa Melappa Lavanya Chandramouli Sanjukta Mazumdar Ekaterina Silina Victor Stupin Chandrashekar Srinivasa Chandan Shivamallu Shiva Prasad Kollur 《Molecules (Basel, Switzerland)》2022,27(8)
Cancer is one of the leading causes of death worldwide, accountable for a total of 10 million deaths in the year 2020, according to GLOBOCAN 2020. The advancements in the field of cancer research indicate the need for direction towards the development of new drug candidates that are instrumental in a tumour-specific action. The pool of natural compounds proves to be a promising avenue for the discovery of groundbreaking cancer therapeutics. Elaeocarpus ganitrus (Rudraksha) is known to possess antioxidant properties and after a thorough review of literature, it was speculated to possess significant biomedical potential. Green synthesis of nanoparticles is an environmentally friendly approach intended to eliminate toxic waste and reduce energy consumption. This approach was reported for the synthesis of silver nanoparticles from two different solvent extracts: aqueous and methanolic. These were characterized by biophysical and spectroscopic techniques, namely, UV-Visible Spectroscopy, FTIR, XRD, EDX, DLS, SEM, and GC-MS. The results showed that the nanoconjugates were spherical in geometry. Further, the assessment of antibacterial, antifungal, and antiproliferative activities was conducted which yielded results that were qualitatively positive at the nanoscale. The nanoconjugates were also evaluated for their anticancer properties using a standard MTT Assay. The interactions between the phytochemicals (ligands) and selected cancer receptors were also visualized in silico using the PyRx tool for molecular docking. 相似文献
513.
Ibrahim Ahmed Shaikh Uday M. Muddapur Zabin K. Bagewadi Sneha Chiniwal Mohammed M. Ghoneim Mater H. Mahnashi Fahad Alsaikhan Deepak Yaraguppi Francois N. Niyonzima Sunil S. More Basheerahmed Abdulaziz Mannasaheb Amer Al Ali Abdulaziz Asiri Aejaz Abdullatif Khan S. M. Shakeel Iqubal 《Molecules (Basel, Switzerland)》2022,27(9)
The applications of bioactive compounds from medicinal plants as therapeutic drugs are largely increasing. The present study selected the bioactive compounds from Acacia concinna (A. concinna) and Citrus limon (C. limon) to assess their phytochemicals, proteins, and biological activity. The plant material was collected, and extraction performed as per the standard procedure. Qualitative analysis was undertaken, and identification of functional organic groups was performed by FTIR and HPLC. Antibacterial, anticancer, antioxidant, antihyperglycemic, antihyperlipidemic, and inhibition kinetics studies for enzymes were performed to assess the different biological activities. Flavonoids and phenols were present in a significant amount in both the selected plants. A. concinna showed significant antimicrobial activity against Z. mobilis, E. coli, and S. aureus, with minimum inhibition zones (MIZ) of 24, 22, and 20 mm, respectively. C. limon strongly inhibited all the tested pathogenic bacteria with maximum and minimum MIZ of 32 and 17 mm. A. concinna silver nanoparticles also exhibited potent antimicrobial activity. Both extracts showed substantial antioxidant, antihyperlipidemic, antidiabetic, anticancer (MCF-7), and anti-urease (antiulcer) properties. To conclude, these plants can be used to treat hyperlipidemia, diabetes, cancer, and gastrointestinal ulcers. They can also serve as antimicrobial and antioxidant agents. Thus, the studied plants must be exploited cost-effectively to generate therapeutic drugs for various diseases. 相似文献
514.
Om Prakash Rajesh Kumar Deepak Sharma Rajesh Naithani Ravi Kumar 《Heteroatom Chemistry》2006,17(7):653-655
Oxidation of bis‐2,4‐pyrimidinylhydrazones of various araldehydes with two equivalents of iodobenzene diacetate in dichloromethane provides an efficient and easy method for the synthesis of eight new 3,9‐diaryl‐bis‐1,2,4‐triazolo[4,3‐a][4,3‐c]pyrimidines. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:653–655, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20250 相似文献
515.
Arjun Kumar Kalimuthu Parasuraman Pavadai Theivendren Panneerselvam Ewa Babkiewicz Joanna Pijanowska Piotr Mrwka Gopalan Rajagopal Venkataraman Deepak Krishnan Sundar Piotr Maszczyk Selvaraj Kunjiappan 《Molecules (Basel, Switzerland)》2022,27(24)
Endophytic fungi are a diverse group of microorganisms that colonize the inter- or intracellular spaces of plants and exhibit mutual benefits. Their interactions with the host plant and other microbiomes are multidimensional and play a crucial role in the production of secondary metabolites. We screened bioactive compounds present in the extracts of Aspergillus flavus, an endophytic fungus isolated from the roots of the medicinal grass Cynodon dactylon, for its anticancer potential. An in vitro analysis of the Ethyl acetate extract from A. flavus showed significant cytostatic effects (IC50: 16.25 μg/mL) against breast cancer cells (MCF-7). A morphological analysis of the cells and a flow cytometry of the cells with annexin V/Propidium Iodide suggested that the extract induced apoptosis in the MCF-7 cells. The extract of A. flavus increased reactive oxygen species (ROS) generation and caused a loss of mitochondrial membrane potential in MCF-7 cells. To identify the metabolites that might be responsible for the anticancer effect, the extract was subjected to a gas chromatography-mass spectrometry (GC-MS) analysis. Interestingly, nine phytochemicals that induced cytotoxicity in the breast cancer cell line were found in the extract. The in silico molecular docking and molecular dynamics simulation studies revealed that two compounds, 2,4,7-trinitrofluorenone and 3α, 5 α-cyclo-ergosta-7,9(11), 22t-triene-6beta-ol exhibited significant binding affinities (−9.20, and −9.50 Kcal/mol, respectively) against Bcl-2, along with binding stability and intermolecular interactions of its ligand-Bcl-2 complexes. Overall, the study found that the endophytic A. flavus from C. dactylon contains plant-like bioactive compounds that have a promising effect in breast cancer. 相似文献
516.
Ananta Dey Manisha Yadav Deepak Kumar Anik Kumar Dey Sweety Samal Subhash Tanwar Debrupa Sarkar Sumit Kumar Pramanik Susmita Chaudhuri Amitava Das 《Chemical science》2022,13(34):10103
Bacteria organized in biofilms show significant tolerance to conventional antibiotics compared to their planktonic counterparts and form the basis for chronic infections. Biofilms are composites of different types of extracellular polymeric substances that help in resisting several host-defense measures, including phagocytosis. These are increasingly being recognized as a passive virulence factor that enables many infectious diseases to proliferate and an essential contributing facet to anti-microbial resistance. Thus, inhibition and dispersion of biofilms are linked to addressing the issues associated with therapeutic challenges imposed by biofilms. This report is to address this complex issue using a self-assembled guanidinium–Ag(0) nanoparticle (AD-L@Ag(0)) hybrid gel composite for executing a combination therapy strategy for six difficult to treat biofilm-forming and multidrug-resistant bacteria. Improved efficacy was achieved primarily through effective biofilm inhibition and dispersion by the cationic guanidinium ion derivative, while Ag(0) contributes to the subsequent bactericidal activity on planktonic bacteria. Minimum Inhibitory Concentration (MIC) of the AD-L@Ag(0) formulation was tested against Acinetobacter baumannii (25 μg mL−1), Pseudomonas aeruginosa (0.78 μg mL−1), Staphylococcus aureus (0.19 μg mL−1), Klebsiella pneumoniae (0.78 μg mL−1), Escherichia coli (clinical isolate (6.25 μg mL−1)), Klebsiella pneumoniae (clinical isolate (50 μg mL−1)), Shigella flexneri (clinical isolate (0.39 μg mL−1)) and Streptococcus pneumoniae (6.25 μg mL−1). Minimum bactericidal concentration, and MBIC50 and MBIC90 (Minimum Biofilm Inhibitory Concentration at 50% and 90% reduction, respectively) were evaluated for these pathogens. All these results confirmed the efficacy of the formulation AD-L@Ag(0). Minimum Biofilm Eradication Concentration (MBEC) for the respective pathogens was examined by following the exopolysaccharide quantification method to establish its potency in inhibition of biofilm formation, as well as eradication of mature biofilms. These effects were attributed to the bactericidal effect of AD-L@Ag(0) on biofilm mass-associated bacteria. The observed efficacy of this non-cytotoxic therapeutic combination (AD-L@Ag(0)) was found to be better than that reported in the existing literature for treating extremely drug-resistant bacterial strains, as well as for reducing the bacterial infection load at a surgical site in a small animal BALB/c model. Thus, AD-L@Ag(0) could be a promising candidate for anti-microbial coatings on surgical instruments, wound dressing, tissue engineering, and medical implants.Dispersion of biofilms that protect bacteria and its subsequent killing in the planktonic state are effectively achieved by a guanidinium–Ag(0) nanocomposite. 相似文献
517.
Deepak Badgurjar Sairaman Seetharaman Prof. Dr. Francis D'Souza Dr. Raghu Chitta 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(6):2184-2195
A panchromatic triad, consisting of benzothiazole (BTZ) and BF2-chelated boron-dipyrromethene (BODIPY) moieties covalently linked to a zinc porphyrin (ZnP) core, has been synthesized and systematically characterized by using 1H NMR spectroscopy, ESI-MS, UV-visible, steady-state fluorescence, electrochemical, and femtosecond transient absorption techniques. The absorption band of the triad, BTZ-BODIPY-ZnP, and dyads, BTZ-BODIPY and BODIPY-ZnP, along with the reference compounds BTZ-OMe, BODIPY-OMe, and ZnP-OMe exhibited characteristic bands corresponding to individual chromophores. Electrochemical measurements on BTZ-BODIPY-ZnP exhibited redox behavior similar to that of the reference compounds. Upon selective excitation of BTZ (≈290 nm) in the BTZ-BODIPY-ZnP triad, the fluorescence of the BTZ moiety is quenched, due to photoinduced energy transfer (PEnT) from 1BTZ* to the BODIPY moiety, followed by quenching of the BODIPY emission due to sequential PEnT from the 1BODIPY* moiety to ZnP, resulting in the appearance of the ZnP emission, indicating the occurrence of a two-step singlet–singlet energy transfer. Further, a supramolecular tetrad, BTZ-BODIPY-ZnP:ImC60, was formed by axially coordinating the triad with imidazole-appended fulleropyrrolidine (ImC60), and parallel steady-state measurements displayed the diminished emission of ZnP, which clearly indicated the occurrence of photoinduced electron transfer (PET) from 1ZnP* to ImC60. Finally, femtosecond transient absorption spectral studies provided evidence for the sequential occurrence of PEnT and PET events, namely, 1BTZ*-BODIPY-ZnP:ImC60→BTZ-1BODIPY*-ZnP:ImC60→BTZ-BODIPY-1ZnP*:ImC60→BTZ-BODIPY-ZnP.+:ImC60.− in the supramolecular tetrad. The evaluated rate of energy transfer, kEnT, was found to be 3–5×1010 s−1, which was slightly faster than that observed in the case of BODIPY-ZnP and BTZ-BODIPY-ZnP, lacking the coordinated ImC60. The rate constants for charge separation and recombination, kCS and kCR, respectively, calculated by monitoring the rise and decay of C60.− were found to be 5.5×1010 and 4.4×108 s−1, respectively, for the BODIPY-ZnP:ImC60 triad, and 3.1×1010 and 4.9×108 s−1, respectively, for the BTZ-BODIPY-ZnP:ImC60 tetrad. Initial excitation of the tetrad, promoting two-step energy transfer and a final electron-transfer event, has been successfully demonstrated in the present study. 相似文献
518.
Colloid Journal - This work concerns the effect of magnetic field on hydrodynamic permeability of biporous membrane relative to the flow of micropolar liquid using four known cell models. The... 相似文献
519.
Jadhav Sagar Donolikar Pratiksha D. Chodankar Nilesh R. Dongale Tukaram D. Dubal Deepak P. Patil Deepak R. 《Journal of Solid State Electrochemistry》2019,23(12):3459-3465
Journal of Solid State Electrochemistry - In present work, we have developed 2.0 V symmetric supercapacitor with rationally prepared iron tungstate (FeWO4) nanoparticles as electrodes and... 相似文献
520.
Sharma Vishal Sharma Rajeev Kamal Razak R. K. Abdul Thakur Deepak Said Zafar Alwetaishi Mamdooh Saleel C Ahamed Afzal Asif 《Journal of Thermal Analysis and Calorimetry》2022,147(22):12595-12615
Journal of Thermal Analysis and Calorimetry - Coniferous forest residue, such as pine needles, has enormous potential in Himalayan territories and could play a significant role in energy supply.... 相似文献