Phytochemicals and Morphological Influence of Aloe Barbadensis Miller Extract Capped Biosynthesis of CdO Nanosticks

Synthesis and characterization of microbial mediated cadmium oxide nanoparticles

Microbial mediated synthesis of metallic nanoparticles constitutes as effective and promising approach for the development of antibacterial materials in the field of bioengineering and biomedicine. We prepared Cadmium oxide nanoaprticles (CdO NPs) utilizing Penicillium oxalicum, and cadmium acetate solution via coprecipitate method. The elemental composition and morphology of these synthesized CdO NPs were examined through X-ray diffraction (XRD), UV-Vis absorption spectroscopy, Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and Energy dispersive spectroscopy (EDS). Furthermore, we evaluated the bactericidal potential of prepared CdO NPs using Escherichia coli (E.coli), Staphylococcus aureus (S.aureus), Bacillus cereus (B.cereus), and Pseudomonas aeruginosa (P. aeruginosa). Dimethyl sulfoxide was used as negative control while erythromycin was used as positive control. The XRD spectrum revealed cubic crystalline nanoparticles with 22.94 nm size and UV showed absorbance peak at 297 nm with 2.5 eV band gap energy. FTIR depicted O─H and carboxylic groups along with CdO stretching vibration. EDS showed the presence of organic compounds on Cd and O over NPs surface. SEM results revealed the spherical shape of the CdO NPs. The synthesized NPs exhibited highly potent bactericidal activity against selected strains and demonstrated less optical density of 0.086 after 24 hr. Owing to the significant antibacterial activity of CdO NPs, the broad application prospects of these nanoparticles CdO NPs in extensive biomedical applications is indicated.

One-pot phytosynthesis of nano-silver from Mentha longifolia L.: their characterization and evaluation of photodynamic potential

The present study deals with the ecofriendly one-pot synthesis and stabilization of silver nanoparticles (AgNPs) by using aqueous extract of Mentha longifolia branches. Spectrophotometric analysis of different ratios of reactants revealed that a 1 to 9 ratio of plant extract and silver salt solution respectively is the most suitable proportion for synthesis. Synthesis of AgNPs was confirmed initially by the observation of change in the color of the reaction mixture which was carried out at 60 °C by using 3 mM of silver salt and the pH of the reaction medium was maintained at 5.22. A characteristic surface plasmon resonance (SPR) band was observed at 495 nm of light wavelength. SEM images revealed that the nanoparticles are in ∼20–80 nm and are anisotropic and nearly spherical while EDX analysis showed the presence of elemental Ag with ∼90% signal intensity. Size distribution analysis of AgNPs was performed by dynamic light scattering technique and AgNPs were found in the range of ∼8–30 nm. ROS quantification revealed that the AgNPs have a quantum yield of 0.09 Φ which provides them the ability to proteolytically treat cancer and other microbial pathogenic cells. AgNPs did not report any photothermal activity to be used as photodynamic agents. These findings explain the redox potential of M. longifolia to bio-fabricate AgNPs and their abilities to generate ROS may help to curb dreading diseases.