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Although, different plant species were utilized for the fabrication of polymorphic, hexagonal, spherical, and nanoflower ZnO NPs with various diameters, few studies succeeded in synthesizing small diameter ZnO nanorods from plant extract at ambient temperature. This work sought to pioneer the ZnO NPs fabrication from the aqueous extract of a Mediterranean salt marsh plant species Limoniastrum monopetalum (L.) Boiss. and assess the role of temperature in the fabrication process. Various techniques have been used to evaluate the quality and physicochemical characteristics of ZnO NPs. Ultraviolet–visible spectroscopy (UV–VIS) was used as the primary test for formation confirmation. TEM analysis confirmed the formation of two different shapes of ZnO NPs, nano-rods and near hexagonal NPs at varying reaction temperatures. The nano-rods were about 25.3 and 297.9 nm in diameter and in length, respectively while hexagonal NPs were about 29.3 nm. The UV–VIS absorption spectra of the two forms of ZnO NPs produced were 370 and 365 nm for nano-rods and hexagonal NPs, respectively. FT-IR analysis showed Zn–O stretching at 642 cm−1 and XRD confirmed the crystalline structure of the produced ZnO NPs. Thermogravimetric analysis; TGA was also used to confirm the thermal stability of ZnO NPs. The anti-tumor activities of the two prepared ZnO NPs forms were investigated by the MTT assay, which revealed an effective dose-dependent cytotoxic effect on A-431 cell lines. Both forms displayed considerable antioxidant potential, particularly the rod-shaped ZnO NPs, with an IC50 of 148.43 µg mL−1. The rod-shaped ZnO NPs were superior candidates for destroying skin cancer, with IC50 of 93.88 ± 1 µg mL−1 ZnO NPs. Thus, rod-shaped ZnO NPs are promising, highly biocompatible candidate for biological and biomedical applications. Furthermore, both shapes of phyto-synthesized NPs demonstrated effective antimicrobial activity against various pathogens. The outcomes highlight the potential of phyto-synthesized ZnO NPs as an eco-friendly alternative for water and wastewater disinfection. [ABSTRACT FROM AUTHOR]

The aim of current study was to prepared zinc oxide nanofertilzers by ecofriendly friendly, economically feasible, free of chemical contamination and safe for biological use. The study focused on crude extract of Withania coagulans as reducing agent for the green synthesis of ZnO nano-particles. Biosynthesized ZnO NPs were characterized by UV–Vis spectroscopy, XRD, FTIR and GC–MS analysis. However, zinc oxide as green Nano fertilizer was used to analyze responses induced by different doses of ZnO NPs [0, 25, 50,100, 200 mg/l and Zn acetate (100 mg/l)] in Triticum aestivum (wheat). The stimulatory and inhibitory effects of foliar application of ZnO NPs were studied on wheat (Triticum aestivum) with aspect of biomass accumulation, morphological attributes, biochemical parameters and anatomical modifications. Wheat plant showed significant (p < 0.01) enhancement of growth parameters upon exposure to ZnO NPs at specific concentrations. In addition, wheat plant showed significant increase in biochemical attributes, chlorophyll content, carotenoids, carbohydrate and protein contents. Antioxidant enzyme (POD, SOD, CAT) and total flavonoid content also confirmed nurturing impact on wheat plant. Increased stem, leaf and root anatomical parameters, all showed ZnO NPs mitigating capacity when applied to wheat. According to the current research, ZnO NPs application on wheat might be used to increase growth, yield, and Zn biofortification in wheat plants. [ABSTRACT FROM AUTHOR]

Chlorogenic acid (CA) is an effective ingredient that can strengthen immunity during following the COVID-19 era. The current cost of CA is high owing to its complex purification process and low yield (approximately 2%). In this study, a one-step path orthogonal experiment was designed based on the results from Gauss calculation, which consisted of acidity, coordination, and hydrolysis in molecules. The optimized extraction conditions were 60 ℃, 60 min, 1:20 liquid ratio, and 40% ethanol in a nitrogen atmosphere controlled using a device of our own design, which led to CA yields of up to 6.35% from potato leaves. The purified CA was analyzed using high-performance liquid chromatography, thin-layer chromatography, ultraviolet–visible spectroscopy, and molecular fluorescence. This accurate and reproducible method can not only be used to obtain high yields of CA but can also be used for the quality control of active plant products and their isomers. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increasing interest in the green synthesis of metallic nanoparticles, mostly because of the evident limitations associated with chemical and physical methods. Green synthesis, commonly referred to as "biogenic synthesis," is seen as an alternative approach to produce AgNPs (silver nanoparticles). The current work focuses on the use of Asterarcys sp. (microalga) for biological reduction of AgNO3 to produce AgNPs. The optimal parameters for the reduction of AgNPs were determined as molarity of 3 mM for AgNO3 and an incubation duration of 24 h at pH 9, using a 20:80 ratio of algal extract to AgNO3. The biosynthesized Ast-AgNPs were characterised using ultraviolet–visible spectroscopy (UV–Vis), zeta potential, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and high-resolution transmission electron microscopy (HR-TEM) with selected area electron diffraction (SAED) patterns. The nanoparticles exhibited their highest absorption in the UV–visible spectra at 425 nm. The X-ray diffraction (XRD) investigation indicated the presence of characteristic peaks at certain angles: 38.30° (1 1 1), 44.40° (2 0 0), 64.64° (2 2 0), and 77.59° (3 1 1) according to the JCPDS file No. 04-0783. Based on SEM and TEM, the Ast-AgNPs had an average size of 35 nm and 52 nm, respectively. The zeta potential was determined to be − 20.8 mV, indicating their stability. The highest antibacterial effectiveness is shown against Staphylococcus aureus, with a zone of inhibition of 25.66 ± 1.52 mm at 250 μL/mL conc. of Ast-AgNPs. Likewise, Ast-AgNPs significantly suppressed the growth of Fusarium sp. and Curvularia sp. by 78.22% and 85.05%, respectively, at 150 μL/mL conc. of Ast-AgNPs. In addition, the Ast-AgNPs exhibited significant photocatalytic activity in degrading methylene blue (MB), achieving an 88.59% degradation in 120 min, revealing multiple downstream applications of Ast-AgNPs. [ABSTRACT FROM AUTHOR]

This study involved the production of 20 biochar samples derived from secondary medicinal residues of Snow Lotus Oral Liquid, processed within the temperature range of 200–600 °C. Additionally, four medicinal residues, including dissolved organic matter (DOM), from 24 samples obtained using the shaking method, served as the primary source material. The investigation focused on two key factors: the modifier and preparation temperature. These factors were examined to elucidate the spectral characteristics and chemical properties of the pharmaceutical residues, biochar, and DOM. To analyze the alterations in the spectral attributes of biochar and medicinal residues, we employed near-infrared spectroscopy (NIR) in conjunction with Fourier-infrared one-dimensional and two-dimensional correlation spectroscopy. These findings revealed that modifiers enhanced the aromaticity of biochar, and the influence of preparation temperature on biochar was diminished. This observation indicates the stability of the aromatic functional group structure. Comparative analysis indicated that Na2CO3 had a more pronounced structural effect on biochar, which is consistent with its adsorption properties. Furthermore, we utilized the fluorescence indices from UV–visible spectroscopy and excitation-emission-matrix spectra with the PARAFAC model to elucidate the characteristics of the fluorescence components in the DOM released from the samples. The results demonstrated that the DOM released from biochar primarily originated externally. Aromaticity reduction and increased decay will enhance the ability of the biochar to bind pollutants. Those results confirmed the link between the substantial increase in the adsorption performance of the high-temperature modified charcoal in the previous study and the structural changes in the biochar. We investigated the structural changes of biochar and derivative DOM in the presence of two perturbing factors, modifier and preparation temperature. Suitable modifiers were selected. Preparation for the study of adsorption properties of snow lotus medicinal residues. [ABSTRACT FROM AUTHOR]

Efficient separation of electron–hole pairs remains pivotal in optimizing photogenerated carrier functionality across diverse catalytic and optoelectronic systems. This study presents the fabrication of a novel hollow direct Z-scheme photocatalyst, ZnO/TiO2. A thorough analysis encompassing various techniques such as Ultraviolet–Visible Spectroscopy (UV–Vis), X-ray Diffraction (XRD), Transmission electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FT-IR), Thermogravimetric Analysis (TGA), and Energy-Dispersive X-ray Spectroscopy (EDX) provided detailed insights into the complex material characteristics of the ZnO/TiO2 heterojunction catalyst. The findings revealed coexisting anatase TiO2 and wurtzite ZnO phases, each retaining distinct attributes within the nanocomposites (NCs) structure. The study showcased the photocatalytic efficacy of ZnO/TiO2-NCs in decomposing Methylene Blue and Acridine Orange under UV irradiation, correlated with their underlying structures. Enhanced degradation of these dyes resulted from the establishment of a direct Z-scheme heterojunction between ZnO and TiO2. Employing Density Functional Theory (DFT) using Quantum ESPRESSO, this research analyzed phase diagrams and band structures, elucidating electronic properties and structural correlations. The study characterized a ZnO/TiO2 composite, revealing a band gap of 3.1–3.3 eV through UV–Visible spectroscopy and confirming its formation without impurity phases via XRD analysis. TEM and EDX showed uniform element dispersion (Zn: 27%, Ti: 29.62%, C: 5.03%, O: 38.35%). Computational analysis using DFT indicated a reduction in stable phases with increasing temperature. Enhanced dye degradation was observed (MB: 88.9%, AO: 84%), alongside significant antibacterial activity. In the future we predict that research will focus on development of scaled up production and photocatalytic activity through surface modification, while unveiling mechanistic insights and environmental applicability for multifunctional use in water treatment and antibacterial applications, leading to further advancement of the field. [ABSTRACT FROM AUTHOR]

Ag-La-CaTiO3 was used in place of sacrificial agents to assess the influence of operational factors on hydrogen generation in a photocatalytic water splitting system. After being synthesized, the physicochemical features of this substance were accurately described. Several characterization techniques including UV–Vis spectroscopy, FTIR, XRD, XPS, EDX, SEM, TGA, DRS and BET were applied to study the prepared Ag-La-CaTiO3 photocatalyst. Ag-La-CaTiO3 shows a band in the visible wavelength between 400 and 800 nm at < 560 nm compared to the main CaTiO3 band at 350 nm. Ag 4d5s electrons transition to the conduction band (CB), which is responsible for the absorption band at ~ 560 nm (> 2.21 eV). The effects of catalyst concentration, light intensity, and beginning solution pH on the H2 generation rate may all be evaluated simultaneously using experimental design procedures. Up to a maximum threshold, where a drop in the rate of gas evolution occurs, it was confirmed that the increase in catalyst dose positively affects system productivity. The initial solution pH plays a crucial role in H2 production, and pH = 4 and 10 are the optimum pH with a higher yield of H2 production. The highest total H2 production rate, 6246.09 μmol, was obtained using a catalyst concentration of 700 mg and solution pH equal to 10 under 1200 W Vis lamp for 3 h. For prediction and optimization, a D-Optimal design was applied and the optimal results were pH 4, the catalyst dose of 645.578 mg and 1200 W with H2 production of 6031.11 μmol. [ABSTRACT FROM AUTHOR]

In this study, a ZnO/MnO nanocomposite was myco-fabricated using the isolated endophytic Clonostachys rosea strain EG99 as the nano-factory. The extract of strain EG99, a reducing/capping agent, was successfully titrated with equal quantities of Zn(NO3)2·6H2O and Mn(NO3)2·6H2O (precursors) in a single step to fabricate the rod-shaped ZnO/MnO nanocomposite of size 6.22 nm. The ZnO/MnO nanocomposite was myco-fabricated in 20 min, and the results were validated at 350 and 400 nm using UV–Vis spectroscopy. In a 7-L bioreactor, an industrial biotechnological approach was used to scale up the biomass of this strain, EG99, and the yield of the myco-fabricated ZnO/MnO nanocomposite. A controlled fed-batch fermentation system with a specific nitrogen/carbon ratio and an identical feeding schedule was used in this production process. Higher yields were obtained by adopting a controlled fed-batch fermentation approach in a 7-L bioreactor with a regular feeding schedule using a nitrogen/carbon ratio of 1:200. Overall, the fed-batch produced 89.2 g/l of biomass at its maximum, 2.44 times more than the batch's 36.51 g/l output. Furthermore, the fed-batch's maximum ZnO/MnO nanocomposite yield was 79.81 g/l, a noteworthy 14.5-fold increase over the batch's yield of 5.52 g/l. Finally, we designed an innovative approach to manage the growth of the endophytic strain EG99 using a controlled fed-batch fermentation mode, supporting the rapid, cheap and eco-friendly myco-fabrication of ZnO/MnO nanocomposite. At a dose of 210 µg/ml, the tested myco-fabricated ZnO/MnO nanocomposite exhibited the maximum antibacterial activity against Staphylococcus aureus (98.31 ± 0.8%), Escherichia coli (96.70 ± 3.29%), and Candida albicans (95.72 ± 0.95%). At the same dose, Staphylococcus aureus biofilm was eradicated in 48 h; however, Escherichia coli and Candida albicans biofilms needed 72 and 96 h, respectively. Our myco-fabricated ZnO/MnO nanocomposite showed strong and highly selective antagonistic effects against a variety of multidrug-resistant human pathogens. Therefore, in upcoming generations of antibiotics, it might be employed as a nano-antibiotic. [ABSTRACT FROM AUTHOR]