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Background: Ayurvedic Ariṣṭa preparations hold an age-old heritage in the prevention and cure of metabolic disorders and associated complications. Aim: The aim of the study was to study the antidiabetic activity of a self-fermented Ariṣṭa preparation (DB-07) and its potential in preventing or curing diabetes-induced nephropathy in experimental models. Materials and Methods: Rats with Streptozotocin-induced diabetes were used for studying the various dose effects of DB-07 (2.5, 3, and 3.5 ml/kg/day) in preventive and therapeutic treatment schedules. Metformin (500 mg/kg) was used as a standard drug. Fasting blood glucose and biochemical parameters such as blood protein, urea, uric acid, and creatinine were accessed by various biochemical tests. In vitro α-amylase and α-glucosidase inhibition assay and 2-deoxy glucose uptake assay using rat L6 myotubes were studied for determining the antidiabetic mechanism of action. Results: A dose-dependent and statistically significant effect on lowering the fasting blood glucose level was observed in both preventive and therapeutic scheduled treatments. Treatment with DB-07 significantly reversed the altered biochemical parameters and the effects were comparable to metformin-treated rats. DB-07 exhibited concentration-dependent inhibition of both α-amylase and α-glucosidase enzymes with an IC50 values of 10.93 μg/ml and 8.73 μg/ml, respectively. DB-07 also showed glucose uptake potential (ca. 70% activity at 125 μg/ml) in differentiated L6 myotubes. Conclusions: These observations have revealed the antidiabetic and nephroprotective potential of DB-07. DB-07 can be a potential herbal alternative to maintain a healthy blood glucose level and will prove useful in diabetes-associated renal complications. [ABSTRACT FROM AUTHOR]

We report the synthesis of Cu doped SnO2 nanostructures with enhanced CO gas sensing properties by a facile wet chemical method. The effects of Cu doping on the structural and optical properties of SnO2 nanostructures were investigated using X-ray diffraction, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and high resolution TEM (HRTEM) with energy dispersive X-ray spectroscopy, Raman spectroscopy and photoluminescence spectroscopy. FESEM studies revealed the presence of nanosheets and nanodisc-like structures in Cu doped SnO2 samples. Gas sensing studies showed that the sensor prepared using 1% Cu doped SnO2 nanostructures exhibits highly enhanced CO gas sensing properties as compared to pure SnO2 nanostructures and shows excellent selectivity for CO with negligible interference from CH4, CO2 and NO2. The possible mechanism for the enhanced CO gas sensing properties of Cu doped SnO2 nanostructures is proposed. [ABSTRACT FROM AUTHOR]

The present isolation and identification of napthoquinones from roots of Arnebia nobilis Reichb.f. can lead to the discovery of new anti-skin ageing ingredient in colour cosmetics. Four compounds have been isolated and purified by rigorous column chromatography. The compounds are identified as β, β-dimethylacryl alkannin (AN-I), acetoxyisovaleryl alkannin (AAN-II), acetyl alkannin (AN-III) and alkannin (AN-IV) by interpretation of spectroscopic data. This study is the first to report the isolation of Acetoxyisovaleryl alkannin (AAN-II) from A. nobilis. The IC50 values of the compounds, determined in human skin cells (human dermal fibroblasts and human keratinocytes) and mouse embryonic fibroblasts (NIH3T3) varied significantly among the four alkannins. Among the four compounds, β-acetoxyisovaleryl alkannin (AAN-II) significantly inhibited hydrogen peroxide (H2O2)-induced red blood corpuscle haemolysis and cellular senescence in human dermal fibroblasts. Collagen-I, elastin and involucrin syntheses in human dermal fibroblasts or keratinocytes were up regulated by AAN-II. These results support the potential utility of alkannins as novel anti-ageing ingredients. [ABSTRACT FROM AUTHOR]

Nanocomposite thin films containing Ag nanoparticles embedded in the GeO2–SiO2 matrix were synthesized by the atom beam co-sputtering technique. The structural, optical and plasmonic properties and the chemical composition of the nanocomposite thin films were studied by transmission electron microscopy (TEM) with energy dispersive X-ray spectroscopy (EDX), UV-visible absorption spectroscopy and X-ray photoelectron spectroscopy (XPS). UV-visible absorption studies on Ag–SiO2 nanocomposites revealed the presence of a strong localized surface plasmon resonance (LSPR) peak characteristic of Ag nanoparticles at 413 nm, which showed a blue shift of 26 nm (413 to 387 nm) along with a significant broadening and drastic decrease in intensity with the incorporation of 16 at% of Ge into the SiO2 matrix. TEM studies on Ag–GeO2–SiO2 nanocomposite thin films confirmed the presence of Ag nanoparticles with an average size of 3.8 nm in addition to their aggregates with an average size of 16.2 nm. Thermal annealing in air resulted in strong enhancement in the intensity of the LSPR peak, which showed a regular red shift of 51 nm (from 387 to 438 nm) with the increase in annealing temperature up to 500 °C. XPS studies showed that annealing in air resulted in oxidation of excess Ge atoms in the nanocomposite into GeO2. Our work demonstrates the possibility of controllably tuning the LSPR of Ag nanoparticles embedded in the GeO2–SiO2 matrix by single-step thermal annealing, which is interesting for optical applications. [ABSTRACT FROM AUTHOR]

Solar-driven highly efficient photocatalytic decomposition of toxic organic contaminants using magnetically separable α-Fe 2 O 3 /ZnFe 2 O 4 /ZnO ternary hybrid nanodiscs is reported. α-Fe 2 O 3 /ZnFe 2 O 4 /ZnO ternary hybrid nanostructures were synthesized by microwave-assisted co-precipitation and simple co-precipitation methods and well characterized by XRD, micro-Raman, FESEM and UV–vis spectroscopy. FESEM micrographs revealed nanodiscs in case of microwave-assisted co-precipitation whereas nanoparticles and their aggregates were formed under co-precipitation combined with calcination. XRD and Raman studies confirmed the hybrid nature of prepared α-Fe 2 O 3 /ZnFe 2 O 4 /ZnO nanostructures. Photocatalytic performance of α-Fe 2 O 3 /ZnFe 2 O 4 /ZnO hybrid nanostructures was investigated by carrying out the photodegradation of organic dyes MB and MG under solar light illumination. The prepared α-Fe 2 O 3 /ZnFe 2 O 4 /ZnO ternary hybrid magnetic nanodiscs decomposed MB and MG dyes in only 32 and 24 min, respectively. α-Fe 2 O 3 /ZnFe 2 O 4 /ZnO hybrid nanodiscs showed excellent photocatalytic performance together with reusability and easy magnetic separation demonstrating its suitability for solar-driven photocatalytic water purification applications. In-situ scavenger studies showed •OH radicals are the main active radicals in solar-driven photocatalysis by α-Fe 2 O 3 /ZnFe 2 O 4 /ZnO nanodiscs. The tentative mechanism of growth of α-Fe 2 O 3 /ZnFe 2 O 4 /ZnO ternary hybrid nanodiscs and the photocatalytic mechanism are discussed. [ABSTRACT FROM AUTHOR]

CuO nanostructures with spindle-type morphology were prepared by using a simple wet chemical route. Transmission electron microscopy (TEM), STEM-HAADF, elemental mapping, EDX, Raman spectroscopy, X-ray diffraction (XRD), BET, UV–Vis and PL spectroscopy were used to inspect the morphological, optical and structural properties of the obtained CuO spindles. TEM images clearly revealed the presence of CuO spindles with bimodal size distribution. XRD and Raman studies demonstrated pure monoclinic CuO structure of CuO spindles, while BET analysis revealed high surface area of 41.6 m2/g. PL spectrum of prepared spindle-type CuO nanostructures shows four peaks centered at 411, 437, 484 and 557 nm. The prepared CuO spindles demonstrated strong performance as solar-active photocatalysts for elimination of methyl orange (MO) and methylene blue (MB) from wastewater. Formation process of CuO spindles is proposed and mechanism for the degradation of dyes is systematically investigated. [ABSTRACT FROM AUTHOR]

This study has been endeavoured to investigate the potential of magnetically separable CoFe 2 O 4 –ZnO hybrid nanostructures towards the complete mineralization of organic pollutants. Facile co-precipitation method was performed to obtain CoFe 2 O 4 –ZnO nanostructures, which were well characterized. The structure, composition and morphology of the materials were confirmed via XRD, Raman, FESEM, TEM and HRTEM which revealed the successful formation of CoFe 2 O 4 –ZnO heterojunctions with particle-like morphology having size in range of 10.4–27.6 nm. The optical properties were studied using PL and DRS whereas UV–visible spectroscopy was utilized for examining photocatalytic performance. The photodegradation property of the prepared nanophotocatalysts was assessed by the decomposition of organic dyes and results showed that CoFe 2 O 4 –ZnO nanostructures exhibit highly enhanced performance over pristine CoFe 2 O 4 due to the high light utilization ability and heterojunction formation which delays the charge carrier recombination and improves the photodecomposition capability. Additionally, the novel photocatalyst recycled well up to four consecutive degradation cycles and photocatalytic mechanism supported by scavenger experiments was also proposed. This study provides sunlight responsive magnetically separable CoFe 2 O 4 –ZnO photocatalyst which efficiently achieves the goal of rapid purification wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ce doped ZnO-Au plasmonic nanorods were fabricated by simple thermal decomposition. • UV–vis DRS showed band gap decrease from 3.26 to 3.19 eV on Au decoration. • Ce doped ZnO-Au nanohybrids exhibited enhanced photocatalytic and catalytic performance. • Ce doped ZnO-Au nanohybrids degraded major pollutants in water in only 10 min. • Mechanism of extreme photocatalytic activity of Ce doped ZnO-Au nanohybrids is proposed. Plasmonic Au nanoparticles (NPs) have been deposited onto Ce doped ZnO nanorods prepared through wet chemical route to enhance their photodecomposition performance. The catalytic and photocatalytic performances were evaluated using a series of model pollutants such as 4-nitrophenol, antibiotic levofloxacin, cationic and anionic dyes under sunlight illumination. Various characterization tools such as XRD, Raman, FESEM, TEM, SAED, EDX, XPS, PL and UV–vis spectroscopy were used to examine the structure and physico-chemical properties of the fabricated photocatalysts. XRD, TEM, SAED, EDX, XPS and Raman analyses confirmed the existence of Ce doped ZnO and Au nanostructures while UV–visible absorption studies revealed the presence of SPR of Au NPs in the visible region. The results illustrated that decoration of Au NPs on Ce doped ZnO nanorods makes them outstanding catalyst as well as photocatalyst compared to pure Ce doped ZnO nanorods. The plasmonic nanohybrids with higher Au concentration exhibited superior degradation capability towards reduction and detoxification of 4-NP, decomposition of antibiotic levofloxacin and synthetic dyes, respectively. In addition, detailed study of possible mechanisms behind 4-NP reduction and photodegradation process have been explored. Furthermore, the quenching experiments elucidating · O 2 - radicals as the main active species in the degradation mechanism have also been discussed. Moreover, the prepared Ce doped ZnO-Au hybrid plasmonic nanorods maintained high stability and stunning photoactivity even after four cycles which highlights it as a promising material for wastewater treatment. [ABSTRACT FROM AUTHOR]

Nanostructured thin films of Cu 2 O–CuO with improved photocatalytic and catalytic activities were developed by RF magnetron sputtering. Thickness-dependent optical, structural, morphological, photocatalytic and catalytic performance of the Cu 2 O–CuO films were investigated using field emission scanning electron microscopy (FESEM), XRD, AFM, RBS, UV–Vis absorption, PL and X-ray photoelectron spectroscopy. FESEM analyses showed nanoparticles which increased in size from 7 to 13 nm with increase in sputter deposition time and were confirmed to be of Cu 2 O–CuO from Raman and XPS studies. Increase in thickness of Cu 2 O–CuO thin film from 7 to 50 nm led to increase in surface roughness, decrease in band gap and reduction in PL intensity. Cu 2 O–CuO thin films showed thickness-dependent enhanced photocatalytic and catalytic activities towards degradation of methylene blue, methyl orange and 4-nitrophenol from water. The enhanced light utilization capability, suppressed charge recombination and small crystallite size of the developed nanostructured Cu 2 O–CuO thin films are the key factors responsible for their enhanced photocatalytic and catalytic performance. [ABSTRACT FROM AUTHOR]

Novel magnetically recyclable α-Fe 2 O 3 /CoFe 2 O 4 /Co 3 O 4 ternary nanohybrids were fabricated via microwave irradiation assisted co-precipitation as well as co-precipitation together with calcination and well characterized by FESEM, TEM, HRTEM, XRD, Raman, XPS, time resolved PL and UV–vis spectroscopy. FESEM and TEM results confirmed nanoparticles and nanodisc-like morphology of nanostructures in the samples fabricated via simple co-precipitation and microwave assisted co-precipitation, respectively. Raman, XRD, TEM, HRTEM and XPS studies revealed α-Fe 2 O 3 , CoFe 2 O 4 and Co 3 O 4 phases confirming the ternary hybrid nature of the prepared nanoparticles and nanodisc samples. α-Fe 2 O 3 /CoFe 2 O 4 /Co 3 O 4 hybrid nanodiscs exhibited excellent magnetic separability and enhanced photocatalytic efficiency for the decomposition of MB and MG dyes in water. The photocatalytic mechanism demonstrating the dye degradation process and the role of reactive oxygen species responsible of the decolorization of dye investigated via in-situ scavenger trapping experiment were also discussed. • α-Fe 2 O 3 /CoFe 2 O 4 /Co 3 O 4 nanohybrids were prepared via microwave irradiation assisted co-precipitation. • FESEM revealed nanodiscs and nanoparticles in microwave-assisted co-precipitation and co-precipitation. • Raman, XRD and XPS revealed α-Fe 2 O 3 , CoFe 2 O 4 and Co 3 O 4 confirming the ternary hybrid nature. • Time resolved PL showed improved charge separation in α-Fe 2 O 3 /CoFe 2 O 4 /Co 3 O 4 hybrid nanodiscs. • α-Fe 2 O 3 /CoFe 2 O 4 /Co 3 O 4 hybrid nanodiscs exhibited magnetic separability and enhanced photocatalytic performance. [ABSTRACT FROM AUTHOR]

Nanocomposite thin films of SnO 2 –ZnO were prepared by carbothermal evaporation of mixture of Sn and ZnO without using any catalyst. The nanocomposite thin films were irradiated with 8 MeV Si 3+ ions at room temperature to fluence varying from 1 × 10 14 to 1 × 10 15 ions/cm 2 . Effects of MeV ion irradiation on the structural and optical properties of SnO 2 –ZnO nanocomposites were studied using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) with energy dispersive X-ray spectroscopy, Photoluminescence spectroscopy (PL) and Raman spectroscopy. XRD studies revealed the presence of Sn, SnO 2 and ZnO nanostructures in the as-deposited films. FESEM studies on the irradiated samples revealed the formation of ZnO nanosheets. A tentative growth mechanism underlying the formation of ZnO nanosheets is proposed. Ion irradiation resulted in a significant enhancement in the UV and defect emissions from ZnO and SnO 2 nanostructures in the nanocomposite. [ABSTRACT FROM AUTHOR]

• ZnFe 2 O 4 /ZnO hybrid nanostructures were synthesized by facile co-precipitation. • ZnFe 2 O 4 /ZnO hybrid nanostructures exhibited excellent photocatalytic performance. • ZnFe 2 O 4 /ZnO hybrid nanostructures degraded organic pollutants in only 24 min. • Mechanism of superior photocatalytic activity of ZnFe 2 O 4 /ZnO nanostructures is proposed. [Display omitted] ZnFe 2 O 4 /ZnO heterojunction photocatalysts have been fabricated via simple co-precipitation method and systematically characterized. The structural and morphological analyses using XRD, Raman and FESEM confirmed the formation of ZnFe 2 O 4 /ZnO hybrid nanostructures. The optical properties were analysed via UV–vis DRS, PL and UV–vis absorption spectroscopy. UV–vis DRS studies showed band gap variation from 1.91 to 2.07 eV. The visible light-driven photodegradation activity of the synthesized products was explored by decomposing toxic pollutants in water and the results showed that ZnFe 2 O 4 /ZnO hybrid nanostructures exhibit superior photodegradation performance over pristine ZnFe 2 O 4 nanostructures. The improved photocatalytic performance of ZnFe 2 O 4 /ZnO nanostructures is ascribed to efficient sunlight utilization ability and suppression of recombination of photoinduced charge carriers due to p-n nanoheterojunction formation. In addition, photodegradation mechanism supported with scavenger experiments has been proposed. Besides the excellent photoactivity, ZnFe 2 O 4 /ZnO hybrid nanostructures are outstandingly stable, recyclable and thereby exhibit an enormous potential for large scale photocatalytic applications. [ABSTRACT FROM AUTHOR]

Hybrid nano-structure consisting of silver nanoparticles (Ag NPs) on two dimensional (2D) MoS 2 nanosheets (NS), prepared by liquid exfoliation method and ultrasonic mixing, showed solar energy driven enhanced photocatalytic capability on a model organic dye methylene blue (MB), having possible consequence in water purification. The Schottky junction between the Ag NP and MoS 2 NS interface induces shift of Fermi level to more negative potential, thereby increasing the life time of the charge carriers even more which leads to formation of sink for photo-excited electrons, and the Ag NPs and ultra-small (US) Ag NPs based Ag-MoS 2 samples show quick photocatalytic degradation of MB dye within 30 min (87%) and 8 min (93%), monitored by UV-Vis spectroscopy, with rate constants 64.1 × 10−3 min−1 and 88.6 × 10−3 min−1 respectively. With decreasing size of Ag NPs a wide surface area was covered and quantum confinement occurred which enhanced the electron transfer at the interface. These electrons are relocated to the constitutively existing molecular oxygen to produce numbers of influential oxidative radicals which results in effective degradation of MB. The corresponding photoluminescence spectra show blue shift and quenching with decreasing Ag NP size and lower MoS 2 number of layers, determined by Raman spectroscopy with respect to that of original MoS 2 nanosheet structures. The corresponding microstructures were determined by transmission electron microscopy (TEM), while the chemical composition was found using X-ray photoelectron spectroscopy (XPS). [Display omitted] • Ag/USAg-MoS 2 hybrid structures were prepared by liquid exfoliation method. • Ag/USAg-MoS 2 blue shift indicates increase in band gap due to quantum confinement. • Raman shows Δω was 19.76 cm−1, which confirms that, USAg-MoS 2 consist of bilayers. • Ag/USAg-MoS 2 exhibits enhanced photocatalytic activity towards MB degradation within 8 min. [ABSTRACT FROM AUTHOR]

• ZnO nanowires and nanoplates were prepared by one-step rapid thermal decomposition. • FESEM and TEM studies revealed ZnO nanowires and nanoplates at 300 °C. • XRD revealed crystallite size variation from 47 to 34 nm and changes in lattice strain. • PL studies showed significant quenching of defect emissions at higher thermal decomposition temperature. • ZnO nanowires and nanoplates exhibited extremely enhanced photocatalytic performance. ZnO nanowires and nanoplates with extremely enhanced photocatalytic performance were prepared via one-step facile thermal decomposition of zinc acetate dihydrate and well characterized by FESEM, TEM, STEM-HAADF, EDX, XRD, PL, XPS, UV–Vis and Raman spectroscopy. FESEM and TEM studies revealed ZnO nanowires, nanoplates and few nanorods in the sample prepared at 300 °C, while increase in the thermal decomposition temperature to 500 °C led to the formation of ZnO nanoparticles and nanorods. XRD results revealed hexagonal wurtzite ZnO nanostructures with crystallite size variation from 47 to 34 nm with increase in thermal decomposition temperature, while PL studies showed decrease in band gap from 3.31 to 3.26 eV along with significant quenching of defect emissions as the thermal decomposition temperature was increased from 300 to 500 °C. ZnO nanowires and nanoplates prepared at 300 °C exhibited extremely enhanced photocatalytic performance and led to almost complete decomposition of methylene blue (MB) and methyl orange (MO) in only 6 and 32 min, respectively. The extremely strong photocatalytic performance of ZnO nanowires and nanoplates makes them exciting candidates for solar-driven water purification. The possible mechanisms of growth of ZnO nanowires and nanoplates and their enhanced photocatalytic performance were proposed. [ABSTRACT FROM AUTHOR]