Physico-chemical and antifungal studies of spun cotton thread reinforced cellulose film.

This study examines cellulose films reinforced with spun cotton thread and their antifungal properties. The morphology and structure of the cellulose film are analyzed using various techniques, including X-ray Diffraction (XRD), Fourier Transform Infrared (FT-IR) Spectroscopy, Field Emission Scanning Electron Microscope (FE-SEM), Atomic Force Microscope (AFM), UV-Visible Spectroscopy (UV-Vis), Thermogravimetric Analysis (TGA), and Differential Scanning Calorimetry (DSC). The XRD pattern confirms the crystalline nature of the spun cotton-reinforced cellulose film. UV absorption analysis shows activity in the UV region of the optical spectrum. The reinforced cellulose film shows a band gap of 4.7 eV by employing the Wood and Tauc equation. FTIR spectroscopy confirms the film's structural formation. Morphological analysis reveals a random distribution of numerous pore structures on the material's surface. Thermalgravimetric Analysis indicates the material's stability at elevated temperatures, suggesting versatile applications. The film also exhibits antifungal activity against Candida albicans. This research highlights the potential of reinforced cellulose film in various applications, such as food and non-food packaging, offering enhanced UV protection and strength for heavy goods transport. The study emphasizes the multifunctional properties of the material, showcasing its promising role as a polymer in various practical applications.

Harnessing the power of gold: advancements in anticancer gold complexes and their functionalized nanoparticles.

Cancer poses a formidable challenge, necessitating improved treatment strategies. Metal-based drugs and nanotechnology offer new hope in this battle. Versatile gold complexes and functionalized gold nanoparticles exhibit unique properties like biologically inert behaviour, outstanding light absorption, and heat-conversion abilities. These nanoparticles can be finely tuned for drug delivery, enabling precise and targeted cancer therapy. Their exceptional drug-loading capacity and low toxicity, stemming from excellent stability, biocompatibility, and customizable shapes, make them a promising option for enhancing cancer treatment outcomes and improving diagnostic imaging. Leveraging these attributes, researchers can design more effective and targeted cancer therapeutics. The potential of functionalized gold nanoparticles to advance cancer treatment and diagnostics holds a promising avenue for further exploration and development in the fight against cancer. This review article delves into the finely tuned attributes of functionalized gold nanoparticles, unveiling their potential for application in drug delivery for precise and targeted cancer therapy.

Fabrication of metal incorporated polymer composite: An excellent antibacterial agent.

US Food and Drug Administration (FDA) allowed for direct addition of castor oil for human consumption as food and most recently FDA approved castor oil as over-the-counter (OTC) for laxative drug. The present article highlights the green route phosphorylation of castor oil (COL) via condensation polymerization. Further, the incorporation of metal ions Cu (II)) and Zn (II) into the polymer matrix have been carried out at elevated temperature using catalyst p-toluene sulphonic acid (PTSA). The modification of the said material has been confirmed by FT-IR, UV-VIS, and 1H and 31P-NMR spectroscopy. Further, the in vitro antibacterial activities of the metal incorporated-COL has been performed by standard methods against B. cereus (MCC2243) (gram-positive) and E. coli (MCC2412) (gram-negative) bacteria. The results revealed that the incorporation of metal ions into the polymer matrix increases the antibacterial activity largely. This may be governed by the electrostatic interaction between metal ions and microbes, also the generation of free active oxygen hinders the normal activity of bacteria. These results suggest that the synthesized material may act a potential candidate for low cost, environment friendly antibacterial agents and may find their application in clinical fields. Herein we are also proposing mechanism of antibacterial activity.

Unravelling the anticancer potential of a square planar copper complex: toward non-platinum chemotherapy.

Coordination compounds from simple transition metals are robust substitutes for platinum-based complexes due to their remarkable anticancer properties. In a quest to find new metal complexes that could substitute or augment the platinum based chemotherapy we synthesized three transition metal complexes C1-C3 with Cu(ii), Ni(ii), and Co(ii) as the central metal ions, respectively, and evaluated them for their anticancer activity against the human keratinocyte (HaCaT) cell line and human cervical cancer (HeLa) cell lines. These complexes showed different activity profiles with the square planar copper complex C1 being the most active with IC50 values lower than those of the widely used anticancer drug cisplatin. Assessment of the morphological changes by DAPI staining and ROS generation by DCFH-DA assay exposed that the cell death occurred by caspase-3 mediated apoptosis. C1 displayed interesting interactions with Ct-DNA, evidenced by absorption spectroscopy and validated by docking studies. Together, our results suggest that binding of the ligand to the DNA-binding domain of the p53 tumor suppressor (p53DBD) protein and the induction of the apoptotic hallmark protein, caspase-3, upon treatment with the metal complex could be positively attributed to a higher level of ROS and the subsequent DNA damage (oxidation), generated by the complex C1, that could well explain the interesting anticancer activity observed for this complex.

S-benzyldithiocarbazate imine coordinated metal complexes kill Candida albicans by causing cellular apoptosis and necrosis.

Development of new chemotherapeutic agents and strategies are urgently needed to curb and halt the growing menace caused by hard-to-treat microbes. Coordination of metals to bioactive organic ligands is now considered to be an efficient strategy for delivering bioactive compounds inside the microbial cell membranes. Metal complexes have been effectively used to treat many dreadful diseases were other treatment modalities had failed. Use of metal complexes to treat microbial infections is now conceived to be an alternative and efficient strategy. Towards this, some new homoleptic transition metal complexes, obtained by coordination of metal ions to bioactive S-benzyldithiocarbazate Schiff-base ligands were evaluated for their anti-Candida activity and their potential to disrupt the membrane architecture. The complexes displayed remarkable antifungal activity against a wide spectrum of fluconazole susceptible and resistant Candida albicans isolates, with Ni complex (dtc3) being highly active with minimum inhibitory concentration (MIC) values ranging from 1 to 32 µg/mL. Cell viability assay confirmed the fungicidal activity of these metal complexes, especially the complex dtc3. These metal complexes kill Candida albicans by inducing cellular apoptosis and necrosis thereby causing phosphatidylserine externalization as revealed by Annexin V-FITC and propidium iodide staining assays.

Synthesis and synergistic studies of isatin based mixed ligand complexes as potential antifungal therapeutic agents.

Metal based drugs are important class of chemotherapeutic agents that have the potential to circumvent drug resistance. Increasing drug resistance, treatment failures and limited treatment options necessitates the development of new therapeutic drugs with different mechanisms of action. Towards this direction, we synthesized a series of isatin based mixed ligand complexes of [Cu(dbm)LClH2O] (mlc1), [Co(dbm)LCl2]‒ (mlc2) and [Ni(dbm)LClH2O] (mlc3) and evaluated their antifungal activity alone and in combination with fluconazole (FLC) against seven different Candida albicans isolates. The insight mechanism of antifungal action was revealed by studying apoptosis via terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay. The study revealed that all these compounds showed antifungal activity at varying concentrations with mlc3 as the most potent compound with minimum inhibitory concentration ranging from 0.5-8 µg/mL and minimum fungicidal concentration ranging from 4-16 µg/mL. Upon combination with FLC, most of the interactions were either synergistic (54 %) or additive (32 %) with no antagonistic combination against any of the tested isolate. The study on their mechanism of action revealed that these compounds show apoptotic effect on C. albicans at sub-inhibitory concentrations, suggesting that strategies to target this process may augment the current antifungal treatment modalities.

Probing the antibacterial and anticancer potential of tryptamine based mixed ligand Schiff base Ruthenium(III) complexes.

Development of new chemotherapeutic agents to treat microbial infections and recurrent cancers is of pivotal importance. Metal based drugs particularly ruthenium complexes have the uniqueness and desired properties that make them suitable candidates for the search of potential chemotherapeutic agents. In this study, two mixed ligand Ru(III) complexes [Ru(Cl)2(SB)(Phen] (RC-1) and [Ru(Cl)2(SB)(Bipy)] (RC-2) were synthesised and characterized by elemental analysis, IR, UV-Vis, 1H, 13C NMR spectroscopic techniques and their molecular structure was confirmed by X-ray crystallography. Antibacterial activity evaluation against two Gram-positive (S. pneumonia and E. faecalis) and four Gram-negative strains (P. aurogenosa, K. pneumoniae, S. enterica, and E. coli) revealed their moderate antibacterial activity with MIC value of ≥250 µg/mL. Anticancer activity evaluation against a non-small lung cancer cell line (H1299) revealed the tremendous anticancer activity of these complexes which was further validated by DNA binding and docking results. DNA binding profile of the complexes studied by UV-Visible and fluorescence spectroscopy showed an intercalative binding mode with CT-DNA and an intrinsic binding constant in the range of 3.481-1.015× 105 M-1. Both the complexes were also found to exert weak toxicity to human erythrocytes by haemolytic assay compared to cisplatin. Potential of these complexes as anticancer agents will be further delineated by in vivo studies.

New transition metal complexes with a pendent indole ring: insights into the antifungal activity and mode of action.

Development of new chemotherapeutic agents to treat multidrug-resistant fungal infections to augment the current treatment options is a must. In this direction, a series of mixed ligand complexes was synthesized from a Schiff base (L) obtained by the condensation of 2-hydroxynapthaldehyde and tryptamine, and 1,10-phenanthroline (1,10-phen) as a secondary ligand. Based on spectral characterization and physical measurements an octahedral geometry was assigned to [Co(phen)LClH2O] (C2), [Ni(phen)LClH2O](C3), and [Zn(phen)LClH2O](C4) complexes while a distorted octahedral geometry was assigned to the [Cu(phen)LClH2O](C1) complex. All the synthesized compounds were tested for antifungal activity against 11 Candida albicans isolates, including fluconazole (FLC) resistant isolates, by determining minimum inhibitory concentrations and studying growth curves. MIC results suggest that all the newly synthesized compounds have potent antifungal activity at varying levels. The rapid action of these compounds on fungal cells suggested a membrane-located target for their action.

Efficacy of Novel Schiff base Derivatives as Antifungal Compounds in Combination with Approved Drugs Against Candida Albicans.

BACKGROUND: The increasing incidence of fungal infections, especially caused by Candida albicans, and their increasing drug resistance has drastically increased in recent years. Therefore, not only new drugs but also alternative treatment strategies are promptly required. METHODS: We previously reported on the synergistic interaction of some azole and non-azole compounds with fluconazole for combination antifungal therapy. In this study, we synthesized some non-azole Schiff-base derivatives and evaluated their antifungal activity profile alone and in combination with the most commonly used antifungal drugs- fluconazole (FLC) and amphotericin B (AmB) against four drug susceptible, three FLC resistant and three AmB resistant clinically isolated Candida albicans strains. To further analyze the mechanism of antifungal action of these compounds, we quantified total sterol contents in FLC-susceptible and resistant C. albicans isolates. RESULTS: A pyrimidine ring-containing derivative SB5 showed the most potent antifungal activity against all the tested strains. After combining these compounds with FLC and AmB, 76% combinations were either synergistic or additive while as the rest of the combinations were indifferent. Interestingly, none of the combinations was antagonistic, either with FLC or AmB. Results interpreted from fractional inhibitory concentration index (FICI) and isobolograms revealed 4-10-fold reduction in MIC values for synergistic combinations. These compounds also inhibit ergosterol biosynthesis in a concentration-dependent manner, supported by the results from docking studies. CONCLUSION: The results of the studies conducted advocate the potential of these compounds as new antifungal drugs. However, further studies are required to understand the other mechanisms and in vivo efficacy and toxicity of these compounds.

Heterocyclic Schiff base transition metal complexes in antimicrobial and anticancer chemotherapy.

In recent years, the number of people suffering from cancer and multidrug-resistant infections has sharply increased, leaving humanity without any choice but to search for new treatment options and strategies. Although cancer is considered the leading cause of death worldwide, it also paves the way many microbial infections and thus increases this burden manifold. Development of small molecules as anticancer and anti-microbial agents has great potential and a plethora of drugs are already available to combat these diseases. However, the wide occurrence of multidrug resistance in both cancer and microbial infections necessitates the development of new and potential molecules with desired properties that could circumvent the multidrug resistance problem. A successful strategy in anticancer chemotherapy has been the use of metallo-drugs and this strategy has the potential to be used for treating multidrug-resistant infections more efficiently. As a class of molecules, Schiff bases have been the topic of considerable interest, owing to their versatile metal chelating properties, inherent biological activities and flexibility to modify the structure to fine-tune it for a particular biological application. Schiff base-based metallo-drugs are being researched to develop new anticancer and anti-microbial chemotherapies and because both anticancer and anti-microbial targets are different, heterocyclic Schiff bases can be structurally modified to achieve the desired molecule, targeting a particular disease. In this review, we collect the most recent and relevant literature concerning the synthesis of heterocyclic Schiff base metal complexes as anticancer and anti-microbial agents and discuss the potential and future of this class of metallo-drugs as either anticancer or anti-microbial agents.

Synthesis of Ni(II), Cu(II) and Co(II) complexes with new macrocyclic Schiff-base ligand containing dihydrazide moiety: Spectroscopic, structural, antimicrobial and antioxidant properties.

In this study, the macrocyclic Schiff base ligand (L) derived from 1, 4-dicarbonyl-phenyl-dihydrazide and glyoxal (2:2) and its Ni (II), Cu (II) and Co(II) complexes were synthesised and were characterised by elemental analyses, FTIR, UV-Vis., mass and 1H NMR. The ligand (L) behaves as a tetradentate ligand and coordinates to the metal ions via the nitrogen atoms and the complexes have the mononuclear structures. The synthesised compounds were evaluated for their inhibition potential against bacterial and fungal strains and the assay indicated that the metal complexes exhibited a remarkable antibacterial and antifungal activity against these tested strains. In addition, the antioxidant activity of the compounds was also studied through scavenging effect on DPPH radicals with the copper complex showing enhanced antioxidant activity than other metal complexes.

Design, synthesis and spectroscopic characterization of metal (II) complexes derived from a tetradentate macrocyclic ligand: Study on antimicrobial and antioxidant capacity of complexes.

The paper presents the synthesis of Co(II), Ni(II) and Cu(II) complexes of macrocyclic Schiff base ligand derived from 1, 4-dicarbonyl-phenyl-dihydrazide and ethyl 3-oxobutanoate (2:2). The synthesized ligand and its metal complexes were characterized by elemental analyses, magnetic susceptibility measurements, FTIR, UV-Vis., mass 1H NMR and X-ray diffraction. The Cu(II) complex exhibit distorted octahedral geometry, whereas an octahedral geometry is suggested for other complexes. The synthesized compounds were screened in vitro for their antimicrobial activities to evaluate their inhibiting potential against bacterial species Pseudomonas aeruginosa, Escherichia coli, Salmonella typhimurium, Staphylococcus aureus and fungal species include Aspergillus flavus, Aspergillus fumingatus, and Candida albicans. The complexation led to a remarkable increase in antimicrobial activity. In addition, the antioxidant activity of the compounds was also investigated through scavenging effect on DPPH radicals. The obtained IC50 value of the DPPH activity for the copper complex was higher than other compounds.

Design, synthesis, characterization and antimicrobial/antioxidant activities of 1, 4-dicarbonyl-phenyl-dihydrazide based macrocyclic ligand and its Cu(II), Co(II) and Ni(II) complexes.

Mononuclear transition metal complexes of Cu(II), Co(II) and Ni(II) with a newly synthesised macrocyclic ligand derived from 1, 4-dicarbonyl-phenyl-dihydrazide and 1,2-diphenylethane-1,2-dione (2:2) have been synthesised. The synthesised compounds were characterised by various physical and spectroscopic techniques including elemental analysis, FTIR, Uv-Vis., 1H NMR, mass spectra, magnetic moment and XRD. The investigation of these macrocyclic complexes established that the stability of metal-ligand coordination through N atoms as tetradentate chelates. The metal/ligands ratio of 1:1 was proposed to afford octahedral geometry for the complexes. The antimicrobial activity of the compounds against some bacterial and fungal species were done by well diffusion method and the results shows that the metal complexes have a promising biological activity comparable with the parent ligand against all bacterial and fungal species. The antioxidant activity of the compounds was also studied through scavenging effect on DPPH radicals with the copper complex showing enhanced activity than other compounds. Additionally, the docking studies predicted the high antimicrobial activity due to the interaction of ligand with the protein.

Synthesis, molecular docking and evaluation of antifungal activity of Ni(II), Co(II) and Cu(II) complexes of porphyrin core macromolecular ligand.

Porphyrin core dendrimeric ligand (L) was synthesized by Rothemund synthetic route in which p-hydroxy benzaldehyde and pyrrole were fused together. The prepared ligand was complexed with Ni(II), Cu(II) and Co(II) ions, separately. Both the ligand and its complexes were characterized by elemental analysis and spectroscopic studies (FT-IR, UV-Vis, (1)HNMR). Square planar geometries were proposed for Cu(II), Ni(II) and Co(II) ions in cobalt, Nickel and copper complexes, respectively on the basis of UV-Vis spectroscopic data. The ligand and its complex were screened on Candida albicans (ATCC 10231), Aspergillus fumigatus (ATCC 1022), Trichophyton mentagrophytes (ATCC 9533) and Pencillium marneffei by determining MICs and inhibition zones. The activity of the ligand and its complexes was found to be in the order: CuL ˃ CoL ≈ NiL ˃ L. Detection of DNA damage at the level of the individual eukaryotic cell was observed by commet assay. Molecular docking technique was used to understand the ligand-DNA interactions. From docking experiment, we conclude that copper complex interacts more strongly than rest two.

Au(III)-CTAB reduction by ascorbic acid: preparation and characterization of gold nanoparticles.

Upon addition of tetrachloroauric(III) (HAuCl(4)) to a solution of cetyltrimethylammonium bromide (CTAB), a perfect transparent yellow colored and yellowish-precipitate appears within the time of mixing, indicating the formation of a complex between HAuCl(4) and CTAB. Morphology of gold nanoparticles in situ via chemical reduction of title reaction has been determined by using conventional techniques. The position and shape of the surface plasmon resonance (SRP) band strongly depends on the [ascorbic acid], [HAuCl(4)], [CTAB] and mixing ratio of the reactants. Sub-, post- and dilution-micellar effects are accountable to the aggregation and/or adsorption of gold nanoparticles onto the surface of CTAB. The morphology of particles was altered by changing the [reactants] as well as [CTAB]. A mechanism of nanoparticle formation has been proposed comprising different steps of particle growth.

Shape-directing role of cetyltrimethylammonium bromide in the green synthesis of Ag-nanoparticles using Neem (Azadirachta indica) leaf extract.

The shape-directing role of cetyltrimethylammonium bromide, CTAB, is reported to the green synthesis of Ag-nanoparticles for the first time using Neem (Azadirachta indica) leaf extract. UV-vis spectroscopy, transmission electron microscopy (TEM), and selected area electron diffraction (SAED) patterns were used to monitor the growth kinetics, morphology and crystalline nature of Ag-nanoparticles, respectively. It was observed that the growths of Ag-nanoparticles are stopped within 40 min of reaction time. The Ag-nanoparticles are polydispersed spherical and exhibiting an interesting triangle, flat, plate-like hexagonal and some irregular morphology in presence of different [CTAB]. Hexagonal particles aggregated in a systematic manor, leads to produce a fine tiles-like arrangement of Ag-nanoparticles with dimensions between 10 and 37 nm. The nature of reaction-time curves to the reduction of Ag(+) ions by Neem leaf extract are much different than those observed by us in our earlier studies using different bio-reductants.

Silver nanoplates and nanowires by a simple chemical reduction method.

This paper describes a simple preparation of single-crystalline Ag-nanoparticles including plates, and wires in water by truncated triangular particles for the first time during the reduction of [Ag(NH3)2]⁺ complex with glucose at room temperature. Silver particles were characterized by means of the conventional transmission electron microscopy (TEM) and UV-VIS spectroscopy. Cetyltrimethylammonium bromide, CTAB, plays a number of roles during the redox process by solubilizing the reactants, controlling the nucleation and/or growth of nanoparticles, stabilizing the thus-prepared Ag-nanoparticles and minimizing the formation of Ag2O, AgCl, and AgBr precipitates. It was found that the rate constant and absorbance of silver nanoparticles were sigmoidal to the concentration of silver nitrate.

Anticandidal activity of cinnamaldehyde, its ligand and Ni(II) complex: effect of increase in ring and side chain.

To increase efficacy of cinnamaldehyde as an antimycotic agent, N, N'- Bis (trans-cinnamadehyde) ethylenediimine [C(20)H(20)N(2)] and Ni(II) complex of the type [Ni(C(40)H(40)N(4))Cl(2)] have been synthesized. The ligand [P] and Ni(II) complex have been characterized on the basis of elemental analysis, FTIR, ESI- MS, IR, (1)H NMR, UV-Vis spectroscopic techniques, conductivity and magnetic measurements. MIC of cinnamaldehyde against clinical isolate of Candida albicans and Candida tropicalis was 400 microg/ml and 500 microg/ml, respectively. Synthesized ligand has markedly reduced MIC; 200 microg/ml and 300 microg/ml whereas Ni(II) complex of ligand displayed MIC of 90 microg/ml and 120 microg/ml. Growth and sensitivity of the organisms were effected by ligand & complex at significantly reduced concentration. Plasma membrane ATPase activity and ergosterol content have been investigated as site of action. Result obtained indicates ergosterol biosynthesis pathway as site of action of cinnamaldehyde, synthesized ligand and its Ni(II) complex.