Algal macromolecular mediated synthesis of nanoparticles for their application against citrus canker for food security.

Citrus canker is a disease of economic importance and there are limited biocontrol agents available to mitigate it in an integrated manner. This study was conducted to combat citrus canker disease using biologically active nanoparticles (Ag, Cu and ZnO and 300, 900, 1200, and 1500 ppm) synthesized from macromolecules extracted from alga, Oedogonium sp. The synthesis of the nanoparticles was confirmed by UV-Vis Spectroscopy, FTIR, SEM, XRD, and DLS Zeta sizer while their efficacy was tested against Xanthomonas citri by measuring zone of inhibition. Results indicated that Ag and Cu nanoparticles at 1200 ppm exhibit the highest activity against Xanthomonas citri, followed by ZnO at 1500 ppm. The minimum inhibitory concentrations (MIC) of Ag, Cu and ZnO NPs were 1, 2 and 10 mg mL-1, respectively while minimum bactericidal concentrations (MBC) were for Ag and Cu 2, 4 mg mL-1 and for ZnO NPs more then 10 mg mL-1, were required to kill the X. citri. Bacterial growth respectively. Macromolecules extracted from algal sources can produce nanoparticles with bactericidal potential, in the order of Ag > Cu > ZnO to mitigate citrus canker disease and ensuring sustainable food production amid the growing human population.

Elucidating the structural, catalytic, and antibacterial traits of Ficus carica and Azadirachta indica leaf extract-mediated synthesis of the Ag/CuO/rGO nanocomposite.

The present exploration demonstrates the efficient, sustainable, cost-effective, and environment-friendly green approach for the synthesis of silver (Ag)-doped copper oxide (CuO) embedded with reduced graphene oxide (rGO) nanocomposite using the green one-pot method and the green deposition method. Leaf extracts of Ficus carica and Azadirachta indica were used for both methods as reducing and capping agents. The effect of methodology and plant extract was analyzed through different characterization techniques such as UV-visible spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), x-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM). The lowest band gap of 3.0 eV was observed for the Ag/CuO/rGO prepared by the green one-pot method using F. carica. The reduction of graphene oxide (GO) and the formation of metal oxide was confirmed through functional group detection using FT-IR. Calculation of thermodynamic parameters showed that all reactions involved were nonspontaneous and endothermic which shows the stability of nanocomposites. XRD studies revealed the crystallinity, phase purity and small average crystallite size of 32.67 nm. SEM images disclosed that the morphology of the nanocomposites was spherical with agglomeration and rough texture. The particle size of the nanocomposites calculated through HRTEM was found in agreement with the XRD results. The numerous properties of the synthesized nanocomposites enhanced their potential against the degradation of methylene blue, rhodamine B, and ciprofloxacin. The highest percentage degradation of Ag/CuO/rGO was found to be 97%, synthesized using the green one-pot method with F. carica against ciprofloxacin, which might be due to the lowest band gap, delayed electron-hole pair recombination, and large surface area available. The nanocomposites were also tested against the Gram-positive and Gram-negative bacteria. RESEARCH HIGHLIGHTS: Facile synthesis of Ag/CuO/rGO nanocomposite using a green one-pot method and the green deposition method. The lowest band gap of 3.0 eV was observed for nanocomposite prepared by a green one-pot method using Ficus carica. Least average crystallite size of 32.67 nm was found for nanocomposite prepared by a green one-pot method using F. carica. Highest antibacterial and catalytic activity (97%) was obtained against ciprofloxacin with nanocomposite prepared through green one-pot method using F. carica. A mechanism of green synthesis is proposed.

In-vivo (Albino Mice) and in-vitro Assimilation and Toxicity of Zinc Oxide Nanoparticles in Food Materials.

Purpose: Recent advances in nanotechnology have given rise to the potential utilization of nanoparticles as food, nano-medicine/biomedicines. Patient: The study aimed to investigate the effects of nano-zinc oxide (nano-zinc) on the bio-assimilation of mineral (Zn) in mice, aged 3-6 weeks. Methods: ZnO nanoparticles were added to the basal diet as a supplement at amounts of 0.07, 0.14 and 0.21 mg/kg. The synthesized material was characterized by Fourier transform infrared spectrophotometer, particle size, scanning electron microscope, Thermogravimetric Analysis Thermal, X-ray diffraction spectrophotometer and Zeta potential. Results: In-vitro bioavailability of synthesized group ZnO (120 nm) was 43%, whereas for standard group ZnO (50 nm) was reported as 55%. In-vivo bioavailability of zinc oxide illustrated the maximum absorption level compared with the control. In-vivo toxicity was characterized as damage done to the liver and spleen tissues with a high dose of 0.21 mg/kg, while smaller doses indicated no toxic effects. Conclusion: The study provided important insights on the toxicological effects of ZnO nanoparticles, depending on dose rate and bio-assimilation, as well as particles, under various conditions (in-vitro and in-vivo). These findings will motivate further detailed research on nano-based medicine for alleviating malnutrition conditions.

Metal nanoparticles assisted revival of Streptomycin against MDRS Staphylococcus aureus.

The ability of microorganisms to generate resistance outcompetes with the generation of new and efficient antibiotics. Therefore, it is critically required to develop novel antibiotic agents and treatments to control bacterial infections. Green synthesized metallic and metal oxide nanoparticles are considered as the potential means to target bacteria as an alternative to antibiotics. Nanoconjugates have also attracted attention because of their increased biological activity as compared to free antibiotics. In the present investigation, silver nanoparticles (AgNPs), zinc oxide nanoparticles (ZnO NPs), copper oxide nanoparticles (CuO NPs), and iron oxide nanoparticles (FeO NPs) have been synthesized by using leaf extract of Ricinus communis. Characterization of nanoparticles was done by using UV-Vis Spectroscopy, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, Energy Dispersive X-Ray Analyzer, X-ray Diffraction Analysis, and Dynamic Light Scattering Particle Size Analyzer. Interestingly, Streptomycin when combined with AgNPs, ZnO NPs, CuO NPs, and FeO NPs showed enhanced antibacterial activity against clinical isolates of S. aureus which suggested synergism between the nanoparticles and antibiotics. The highest enhanced antibacterial potential of Streptomycin was observed in conjugation with ZnO NPs (11 ± 0.5 mm) against S. aureus. Minimum inhibitory concentration of conjugates of AgNPs, ZnO NPs, CuO NPs, and FeO NPs with streptomycin against S. aureus was found to be 3.12, 2.5,10, and 12.5 µg/mL respectively. The considerable point of the present investigation is that S. aureus, which was resistant to streptomycin becomes highly susceptible to the same antibiotic when combined with nanoparticles. This particular observation opens up windows to mitigate the current crisis due to antibiotic resistance to combat antimicrobial infections efficiently.

Mesoporous ZnAl2Si10O24 nanofertilizers enable high yield of Oryza sativa L.

Controllable release of nutrients in soil can overcome the environmental problems associated with conventional fertilizer. Here we synthesized mesoporous nanocomposite of Zinc aluminosilicate (ZnAl2Si10O24) via co-precipitation method. Oryza sativa L. husk was used as source of silica for making the synthesis process green and economical. The nanocomposite was subsequently loaded with urea to achieve the demand of simultaneous and slow delivery of both zinc and urea. The structural characterization of nanocomposite was done by FTIR, XRD, TGA, BET, SEM/EDX and TEM. The release of urea and zinc was investigated with UV-Vis spectrophotometry and atomic absorption spectroscopy, respectively, up to 14 days. It was noted that urea holding capacity of mesoporous ZnAl2Si10O24 nanocomposite over long period of time was increased as compared to bulk aluminosilicates, due to its high surface area (193.07 m2 g-1) and small particle size of (64 nm). Urea release was found highest in first 24 h because of excess of adsorption on nanocomposite and least at 14th day. Fertilizer efficiency was checked on Oryza sativa L. in comparison with commercial urea and results showed significantly higher yield in case of urea loaded ZnAl2Si10O24 nanocomposite.

Development of Latent Fingermarks on Various Surfaces Using ZnO-SiO2 Nanopowder.

Fingermarks are one of the most useful forms of evidence in identification and can provide generalized proof of identity in crime investigation. They are developed using various conventional powders. The novel nanopowder ZnO-SiO2 was synthesized via the conventional heating method and characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), energy-dispersive X-ray (EDX) analysis, transmission electron microscope (TEM), and X-ray diffraction (XRD). The mean particle size of ZnO-SiO2 nanopowder calculated through TEM was 32.9 nm. The development of fingermarks was carried out by powder dusting and small particle reagent (SPR) methods. Powder dusting method was used for the development of latent fingermarks on various dry, nonporous, and semi-porous surfaces. The SPR method was also applied to wet nonporous surface. The developed latent fingermarks using ZnO-SiO2 nanopowder were found to have excellent quality with very clear third-level ridges detail and had better visibility than commercially available white powder.

Micelle-assisted synthesis of Al2O3·CaO nanocatalyst: optical properties and their applications in photodegradation of 2,4,6-trinitrophenol.

Calcium oxide (CaO) nanoparticles are known to exhibit unique property due to their high adsorption capacity and good catalytic activity. In this work the CaO nanocatalysts were prepared by hydrothermal method using anionic surfactant, sodium dodecyl sulphate (SDS), as a templating agent. The as-synthesized nanocatalysts were further used as substrate for the synthesis of alumina doped calcium oxide (Al2O3·CaO) nanocatalysts via deposition-precipitation method at the isoelectric point of CaO. The Al2O3·CaO nanocatalysts were characterized by FTIR, XRD, TGA, TEM, and FESEM techniques. The catalytic efficiencies of these nanocatalysts were studied for the photodegradation of 2,4,6-trinitrophenol (2,4,6-TNP), which is an industrial pollutant, spectrophotometrically. The effect of surfactant and temperature on size of nanocatalysts was also studied. The smallest particle size and highest percentage of degradation were observed at critical micelle concentration of the surfactant. The direct optical band gap of the Al2O3·CaO nanocatalyst was found as 3.3 eV.

Anti-microbial activities of sulfonamides using disc diffusion method.

Sulfonamides, being the member of the oldest anti-microbial group of compounds possess wide anti-microbial activities and are effective against pathogenic strains of gram-positive and gram-negative bacteria. They are widely used in the treatment of various infectious diseases e.g. malaria, urinary tract infections, respiratory tract infections etc. Based on their effectiveness against most of the bacteria, two novel sulfonamides (N-(2-methoxy phenyl)-4-methylbenzenesulfonamide and N-ethyl-4-methyl-N-(3-methyl phenyl)benzenesulfonamide) were synthesized. The compounds were characterized by FT-IR and elemental analyzer. Their anti-microbial activity was assessed and observed against gram-positive and gram-negative bacteria using disc diffusion method. They showed good anti-microbial activities.

2-(1,3-Dioxoisoindolin-2-yl)acetic acid-N'-[(E)-2-meth-oxy-benzyl-idene]pyridine-4-carbohydrazide (1/1).

In the title 1:1 cocrystal, C(10)H(7)NO(4)·C(14)H(13)N(3)O(2), mol-ecules are linked by inter-molecular C-H⋯O, N-H⋯O and O-H⋯N hydrogen bonds, forming a three-dimensional network. In addition, π-π stacking inter-actions [with centroid-centroid distances of 3.5723 (19) and 3.6158 (18) Å] are observed.

N-[4-(Propyl-sulfamo-yl)phen-yl]acetamide.

In the title compound, C(11)H(16)N(2)O(3)S, the S atom has a distorted tetra-hedral geometry [maximum deviation: O-S-O = 119.48 (15)°]. The dihedral angles between the benzene ring and its propyl-sulfonamide and methyl-amide substituents are 71.8 (2) and 5.8 (1)°, respectively. In the crystal, mol-ecules are linked by N(m)-H⋯O(s) (m = methyl-amide and s = sulfonamide) hydrogen bonds, forming C(8) chains along the a axis. The two mol-ecule chains are connected by N-H⋯O hydrogen bonds, generating R(3) (2)(18) rings. The crystal packing is further stabilized by weak inter-molecular C-H⋯O hydrogen bonds.

N-Ethyl-N-(4-methyl-phen-yl)benzene-sulfonamide.

The title compound, C(15)H(17)NO(2)S, is twisted at the S-N bond with a C-S-N-C torsion angle of 73.90 (14)°. The dihedral angle between the aromatic rings is 36.76 (11)°.

N-{4-[(3-Methyl-phen-yl)sulfamo-yl]phen-yl}acetamide.

In the title compound, C(15)H(16)N(2)O(3)S, the central C-S(=O)(2)N(H)-C unit is twisted, with a C-S-N-C torsion angle of -56.4 (2)°. The benzene rings form a dihedral angle of 49.65 (15)° with each other. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, generating a three-dimensional network.

N-Ethyl-4-methyl-N-(3-methyl-phen-yl)benzene-sulfonamide.

The title compound, C(16)H(19)NO(2)S, crystallizes with two crystallographically independent mol-ecules in the asymmetric unit in which the dihedral angles between the planes defined by the aromatic rings are 35.3 (2) and 42.5 (2)°. In the crystal, inter-molecular C-H⋯O hydrogen bonds stabilize the packing.

N-Benzyl-4-methyl-N-(4-methyl-phen-yl)benzene-sulfonamide.

In the title mol-ecule, C(21)H(21)NO(2)S, the phenyl ring makes the dihedral angles of 74.13 (11) and 80.16 (11)° with the two benzene rings, which are inclined at an angle of 43.73 (10)° with respect to each other. In the crystal, mol-ecules are linked by inter-molecular C-H⋯O hydrogen bonds along the [010] direction. In addition, a weak C-H⋯π (arene) inter-action is observed.

N-{4-[(2-Meth-oxy-phen-yl)sulfamo-yl]phen-yl}acetamide.

In the title compound, C(15)H(16)N(2)O(4)S, the S atom has a distorted tetra-hedral geometry [maximum deviation: O-S-O = 118.25 (7)°]. The two aromatic rings make a dihedral angle of 62.67 (10)° with each other. An intra-molecular N-H⋯O hydrogen bond forms an S(6) ring motif. In the crystal, mol-ecules form centrosymmetric dimers via pairwise N-H⋯O inter-actions, forming an R(2) (2)(8) ring motif, and these dimers are connected by N-H⋯O hydrogen bonds, generating a three-dimensional network. Furthermore, a weak C-H⋯π inter-action helps to reinforce the crystal structure. The O atom in the acetamide group is disordered over two positions with major and minor occupancies of 0.52 (5) and 0.48 (5), respectively.