Removing organic pollutants, textile dyes, and pharmaceutical wastes from the water bodies has become an essential requirement for a safe environment. Therefore, the present study aimed to prepare semiconductor zinc oxide nanoparticles (ZnO NPs) and plasmonic Ag-supported ZnO nanocomposite (ZnO–Ag) using an environmentally friendly bio-approach as an alternative to hazardous synthesis approaches. ZnO NPs and ZnO–Ag nanocomposite were characterized by using UV–Vis diffuse reflectance spectroscopy (UV–DRS) (the Ag-supported ZnO nanocomposite exhibited an absorption band between 450–550 nm, attributed to the Ag NPs surface plasmon resonance (SPR)), Photoluminescence (PL) spectral investigation, which revealed the PL emission intensity of ZnO–Ag NPs was lower than pure ZnO NPs, describing an extended electron-hole pair (e--h+) lifespan of photogenerated charge carriers, Fourier transform infrared spectroscopy (FTIR), FT-Raman, and X-ray diffraction (XRD) analyses were deduced. In addition, energy dispersive X-ray spectroscopy (SEM-EDX), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA) were performed and further ascertained the successful biosynthesis and thermally stable ZnO Nps and ZnO–Ag nanocomposite. The as-prepared ZnO–Ag nanocomposite displayed increased photocatalytic characteristics due to the decline in the bandgap energy from 3.02 eV (ZnO NPs) to 2.90 eV (ZnO–Ag nanocomposite). The photocatalytic activity of the developed nanocomposite for the degradation of methylene blue (MB) dye, a primary textile industry released water-pollutant, was conducted under UV light irradiation. Meanwhile, the maximum % degradation of MB dye molecules was attained by 98.0 % after 60 min exposure of UV-light irradiation. Increased photocatalytic activity of ZnO–Ag nanocomposites and a faster rate of MB degradation were achieved by the deposition of plasmonic Ag NPs and the surface plasmon resonance (SPR) effect possessed by Ag NPs. The primary oxidative route that resulted in MB degradation was the production of hydroxyl radicals (OH^•). The SPR effect of the photocatalyst induced the synergistic enhancement of the optical response and separation of the photo-induced charge carriers. The combined study gives comprehensive information and directions for future research on noble metal-modified nanocatalysts for direct applications in the photocatalytic degradation of textile and organic wastes in water.

The design and development of new cost-effective, clean, and efficient synthesis procedures for the synthesis of nanoparticles have recently become an intriguing research topic with broad implications. This study aimed to develop an eco-friendly biogenic method that uses minimum nontoxic chemicals to yield ZnO nanoparticles with enhanced capabilities for degradation of pharmaceutical by-products. The present study used black dried lemon peel aqueous extract as a biological stabilizing agent to prepare pure and stable zinc oxide nanoparticles (LP-ZnO NPs). The surface morphology, elemental composition, crystalline properties, size, optical properties, the role of functional groups in stabilization, capping, and the thermal stability of LP-ZnO NPs were investigated using scanning electron microscopy equipped with energy dispersive X-ray (SEM-EDX), X-ray diffraction (XRD), UV–visible diffuse reflectance spectroscopy (UV-DRS), PL, Fourier transform infrared (FTIR), Raman spectra, and thermogravimetric (TGA) analyses. Multiphoton resonances were observed in LP-ZnO NPs along the crystalline structure as per Raman analysis. The developed LP-ZnO NPs were thermally stable at an annealing temperature of 500 °C with a weight loss of 53%. Photodegradation of antibiotic ciprofloxacin was observed in the presence of UV light via LP-ZnO NPs (serving as photocatalyst). In addition, in optimal reaction media, the biogenic LP-ZnO NPs retained improved photocatalytic performance toward ciprofloxacin. Meanwhile, in the photodegradation process of CPI molecules via ZnO as a photocatalyst, the optimum catalytic dose, concentration of CIP molecules, and pH were attained at 10 mg, 2 × 10⁻⁵ M, and pH 8, respectively. The aim of this research work was to develop a simple, affordable photocatalytic technique for the photodegradation of antibiotics in aqueous media. The photocatalytic process was performed under different experimental conditions, including varying catalytic doses, ciprofloxacin concentrations, and pH of the reaction mixture.

In terms of reduced toxicity, the biologically inspired green synthesis of nanoparticles has emerged as a promising alternative to chemically fabricated nanoparticles. The use of a highly stable, biocompatible, and environmentally friendly aqueous extract of Cynara cardunculus as a reducing and capping agent in this study demonstrated the possibility of green manufacturing of silver nanoparticles (CC-AgNPs). UV–visible spectroscopy validated the development of CC-AgNPs, indicating the surface plasmon resonance (SPR) λ_max band at 438 nm. The band gap of CC-AgNPs was found to be 2.26 eV. SEM and TEM analysis examined the surface morphology of CC-AgNPs, and micrographs revealed that the nanoparticles were spherical. The crystallinity, crystallite size, and phase purity of as-prepared nanoparticles were confirmed using XRD analysis, and it was confirmed that the CC-AgNPs were a face-centered cubic (fcc) crystalline-structured material. Furthermore, the role of active functional groups involved in the reduction and surface capping of CC-AgNPs was revealed using the Fourier transform infrared (FTIR) spectroscopic technique. CC-AgNPs were mostly spherical and monodispersed, with an average size of 26.89 nm, and were shown to be stable for a longer period without any noticeable change at room temperature. Further, we checked the antifungal mechanism of CC-AgNPs against C. auris MRL6057. The minimum inhibitory concentrations (MIC) and minimum fungicidal concentrations (MFC) were 50.0 µg/mL and 100.0 µg/mL respectively. The cell count and viability assay confirmed the fungicidal potential of CC-AgNPs. Further, the analysis showed that CC-AgNPs could induce apoptosis and G2/M phase cell cycle arrest in C. auris MRL6057. Our results also suggest that the CC-AgNPs were responsible for the induction of mitochondrial toxicity. TUNEL assay results revealed that higher concentrations of CC-AgNPs could cause DNA fragmentation. Therefore, the present study suggested that CC-AgNPs hold the capacity for antifungal drug development against C. auris infections.

Flavonoids are polyphenolic compounds that are mainly derived from fruits and vegetables and constitute an essential part of plant-derived beverages such as green tea, wine and cocoa-based products. They have been shown to possess anticancer effects via different mechanisms such as carcinogen inactivation, antiproliferation, cell cycle arrest, induction of apoptosis and differentiation, inhibition of angiogenesis, anti-oxidation and reversal of multidrug resistance or a combination of any two or more of these mechanisms. The present review summarizes the chemistry, biosynthesis and anticancer evaluation of flavonoids in both animal and human studies. A special emphasis has been placed on the flavonoids that are being screened in different phases of clinical trials for chemoprotective action against various cancers.

This article reports on incorporating magnetic nanoparticles into natural carbon frameworks derived from Nigella Sativa seeds and their synthesis via co-precipitation reactions for application in biomedicine. The magnetic Nigella Sativa Seeds (Magnetic NSS), a metal oxide-based bio-nanomaterial, has shown excellent water diaper presence due to the presence of a wide range of oxygenous hydroxyl and carboxyl groups. The physicochemical properties of the composites were characterized extensively using Fourier transform infrared spectroscopy (FTIR), powder-X-ray diffraction (XRD), scanning electron microscopy (SEM), elemental analysis, transmission electron microscopy (TEM), and vibrating-sample magnetometer. Furthermore, synthesized magnetic NSS showed antioxidant and antifungal activity. The antifungal susceptibility was further tested against Candida albicans with a MIC value of 3.125 µg/mL. Analysis of antioxidant defense enzymes was determined quantitatively; the results suggested that antioxidant enzyme activity increase with increased magnetic NSS concentration. Furthermore, biofilm inhibition assay from scanning electron microscopy results revealed that magnetic NSS at the concentration of 3.5 μg/mL has anti-biofilm properties and can disrupt membrane integrity.

This study was aimed at establishing the interactions prevailing in an anionic surfactant, sodium dodecyl sulfate, and dopamine hydrochloride in an alcoholic (ethanol) media by using volumetric, conductometric, and tensiometric techniques. Various methods were utilized to estimate the critical micelle concentration (cmc) values at different temperatures. The entire methods yielded the same cmc values. The corresponding thermodynamic parameters viz. the standard free energy of micellization ($G_{mic}^o$), enthalpy of micellization ($H_{mic}^o$), and entropy of micellization ($S_{mic}^o$) were predicted by applying the pseudo-phase separation model. The experimental density data at different temperatures (298.15 K, 303.15 K, 308.15 K, and 313.15 K) were utilized to estimate the apparent molar volumes ($V_{\varphi }^o$) at an infinite dilution, apparent molar volumes ($V_{\phi }^{cmc}$) at the critical micelle concentration, and apparent molar volumes ($\mathsf{\Delta }{V}_{\phi }^m$) upon micellization. Various micellar and interfacial parameters, for example, the surface excess concentration (${\mathsf{\Gamma }}_{\max }$), standard Gibbs free energy of adsorption at the interface ($\mathsf{\Delta }{G}^o{}_{ad}$), and the minimum surface area per molecule ($A_{\min }$), were appraised using the surface tension data. The results were used to interpret the intermolecular interactions prevailing in the mixed systems under the specified experimental conditions.