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A hydrothermal process is applied to fabricate copper-doped dilute magnetic semiconductor nanorods Zn1 − xCuxO (x = 3%). The influence of reaction pH value and synthesis temperature was evaluated on their physical properties' anti-bacterial and photocatalytic activities. XRD denouements imply that the material is crystalline and exhibits hexagonal wurtzite geometry whose crystallinity reduces from 29.86 to 26.1 nm and enhances from 29.86 to 34.83 nm with increasing pH value and synthesis temperature, respectively. The material morphology was switched from nanorods to nanowires, and a blue shift from 3.14 to 3.28 eV was noticed in the optical bandgap along with shifting in various vibrations. The dielectric and electrical measurements showed similar behavior, whereas the relative permeability and saturation magnetization were knocked off by increasing pH value and temperature. The photocatalytic activity results showed the maximum degradation of MO dye (95%) under sunlight using the Cu-doped ZnO synthesized at pH 13 and 130 °C. All the samples were found active to inhibit the growth of bacterial strains. [ABSTRACT FROM AUTHOR]

Dilute magnetic semiconductor Zn1−xCuxO (x = 0, 1.5, 3.0, and 4.5%) nanorods were prepared by hydrothermal method. The impact of dopant concentration on the physical properties was investigated along with the anti-bacterial and photocatalytic activities. Synthesis of ZnO nanorods was confirmed by the characteristic band at 380 nm in UV–Visible spectra of the synthesized samples. A red shift in absorbance spectra was observed from 380 to 465 nm with an increase in dopant concentration. The hexagonal wurtzite geometry and rod-like morphology of Cu-doped ZnO nanorods having an average size of 29 nm were confirmed by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM), respectively. An increase in the crystallinity of the material was observed with an increase in the dopant (Cu) ratio without any alteration in geometry. EDX analysis was used to confirm the purity of samples. FTIR spectra were recorded to explore the functional group present in samples. The hysteresis loop drawn by a vibrating-sample magnetometer (VSM) was utilized to analyze the ferromagnetic behavior. As-synthesized pure and Cu–ZnO nanorods were evaluated for their photocatalytic behavior for the photodegradation of methyl orange (MO) dye. Zn1 − xCuxO with x = 4.5%, pH 3, and catalyst dosage of 0.5 g has shown the maximum efficiency. Results elucidated > 81% degradation of MO dye with a rate constant (k) value of − 1.930 × 10−2 min−1 in just 90 min of exposure to a visible light source. ZnO nanorods have also exhibited anti-bacterial potential against gram-positive and gram-negative strains of bacteria. However, smaller size nanorods were found more effective to suppress the growth of gram-negative bacteria. A slight decrease (11%) in catalytic potential was observed in the 5th cycle during recycling and reuse experiments. [ABSTRACT FROM AUTHOR]

Water pollution is a real threat to existence of life on earth. Among major water pollutants, hazardous organic dyes present in industrial effluents need to be immediately addressed. These dyes can be photodegraded using nanocatalysts. Metal-based nanocatalysts are preferred for photocatalytic applications due to their high surface area and suitable energy band gap to produce and sustain photo-generated electrons and holes. Therefore, AgNPs of different morphology (cubic and rod shape) has been reported in current study. AgNPs in form of nanocubes and nanorods have been synthesized by polyol reduction method using ethylene glycol as reducing agent and polyvinylpyrrolidone (PVP) as capping agent. Effect of etchants (KCl and FeCl2) was studied on the morphology of AgNPs. The prepared nanocubes and nanorods were characterized by UV-visible, powder X-ray diffraction (PXRD), and scanning electron microscope (SEM). Nanocubes and nanorods were eventually evaluated for their photocatalytic potential under sunlight irradiation. Silver nanorods were found more active for photocatalytic degradation of methylene blue (MB) dye with 88% degradation after 110 minutes. Antibacterial potential of AgNPs was also evaluated by disk diffusion method against gram-positive and gram-negative strains. AgNPs were found more noxious against gram-negative bacterial strains. [ABSTRACT FROM AUTHOR]

Traditional uses of plants are one of the important starting points in search of newer and more effective bioactive drug. Rosa brunonii (plant's family; Rosaceae) is an ethnomedicinal shrub found in lesser Himalaya region. In traditional medicines, it is used as "blood purifier, to stimulate wound healing, to treat infectious diseases". So, by considering the medicinal potential of Rosa brunonii, the methanolic fruit's extract was tested against two gram positive and three gram negative bacteria by agar well diffusion method. The maximum antibacterial potential was noticed against Klebsiella pneumoniae (94 ± 0.3 mm inhibition zone, MIC = 62.5 ± 1.1 µg/mL), while minimum antibacterial activity was shown by the plant extract against Bacillus subtilis (MIC = 250 ± 7.2 µg/mL). The cytotoxic properties of crude methanolic extract were determined by brine shrimp lethality test. A dose-dependent cytotoxic effect was observed for the plant extract at p < 0.05, F (3,8) = 1.58 with LD50 220.95 ± 1.03 µg/mL. Antitumor potential was evaluated by potato disk antitumor bioassay. Fruit's extract of R. brunonii showed maximum tumor inhibition at 1000 µg/mL by 72.73% with IC50 = 655.65 ± 0.03 µg/mL. Preliminary phytochemical analysis revealed that extract is devoid of alkaloid but rich in phenolics. Total phenolic and flavonoid contents were determined as 66.73 ± 3.89 µg/mg GAE and 46.51 ± 0.96 µg/mg QE, respectively, in R. brunonii. The present study underlined the ethnomedicinal importance of R. brunonii and promised useful candidate for the search of newer and effective bioactive constituents. [ABSTRACT FROM AUTHOR]

The long history of using plant species as medicines worldwide provides clues for the search for bioactive phytochemicals. One of the important traditional medicinal plant species of Pakistan is Dryopteris ramosa (Dryopteridaceae). The fronds of Dryopteris ramosa are traditionally used for the treatment of gastric ulcer and constipation. The crude methanol extract and aqueous fraction of Dryopteris ramosa exhibited strong free radical scavenging potential. Two xanthonoid compounds, mangiferin and isomangiferin, were isolated from the aqueous fraction of Dryopteris ramosa by chromatographic techniques (CC Sephadex LH20, followed by MPLC and purified by preparative TLC). Their structures were confirmed by spectroscopic analysis MS, NMR (1H, 13C, HSQC and HMBC). This is the first report on isolation of mangiferin and isomangiferin from Dryopteris genus though previously reported in other fern genera, e.g., Cystopteris, Acystopteris, Gymnocarpium and Asplenium. The antioxidant potential of mangiferin (60.34 ± 0.14 μg/mL) and isomangiferin (55.98 ± 0.39 μg/mL) was comparable to ascorbic acid (57.97 ± 0.93 μg/mL), thus representing promising antioxidant agents against oxidative stress. The investigation of the mechanism of free radical scavenging by mangiferin and isomangiferin showed that the catechol moiety was involved in quenching of free radicals. This study justified the traditional use of Dryopteris ramosa confirming the pharmacological properties of isolated compounds. Further phytochemical studies on Dryopteris ramosa are needed for identification of new bioactive phytochemicals in this plant of ethnobotanical relevance. [ABSTRACT FROM AUTHOR]

Substitution of NdZn in CaBaNdZnFeO, ( x = 0.00-0.10; y = 0.00-1.00) hexaferrites prepared by sol-gel method is investigated, and their effect on the microwave, structural, and magnetic properties is reported. The XRD patterns reveal single-phase M-type hexaferrite structure. The lattice parameters were found to increase by the substitution of NdZn. The increase in lattice parameters is due to the difference in ionic sizes of the cations involved. The average grain size was found between 16 and 29 nm by Scherer formula and was also confirmed by SEM and TEM. Magnetic behavior of selected sample was observed up to a magnetic field of 8T taken at temperature ranges from 4.2 to 373 K. The coercivity of the sample decreased from 2300 to 1210 Oe with increasing temperatures in a linear fashion up to 373 K. The grain boundaries, and the associated pinning fields, seem to have a resolute role in the magnetic behavior of these hexaferrites. Microwave measurements of the ferrite sample have been measured in the frequency range 0.5-12 GHz. The frequency dispersion of ferrites is credited to the phenomenon of natural magnetic resonance and domain wall pinning. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]