Synthesis of AgNPs from leaf extract of Naringi crenulata and evaluation of its antibacterial activity against multidrug resistant bacteria.

The biosynthesis of AgNPs using a methanolic extract of Naringi crenulata is described in this study. UV-visible spectroscopy, X-ray diffraction (XRD), Energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), particle size analyzer (PSA), scanning electron microscope (SEM), atomic force microscopy (AFM), and transmission electron microscopy (TEM) were used to characterize the synthesized AgNPs. The UV-visible spectrum revealed a sharp peak at 420 nm, which represents silver's strong Plasmon resonance. FTIR and XRD confirmed the functional groups (N-H stretch, alkanes, O-H stretch, carboxylic acid, N-H bend, C-X fluoride, and C-N stretch) and face-centered cubic crystalline structure of synthesized AgNPs. SEM and TEM analyses revealed that the synthesized nanoparticles had a spherical morphology with an average diameter of 32.75 nm. The synthesized AgNPs have antibacterial activity against multidrug-resistant bacteria pathogens such as Vibrio cholerae, Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli, and Klebsiella pneumoniae. AgNPs can be synthesized using a methanolic extract of Naringi crenulate, and the resulting particle may have wide range of biological applications.

Antibacterial, antifungal, antidiabetic, and antioxidant activities potential of Coleus aromaticus synthesized titanium dioxide nanoparticles.

The nanoparticles based drug delivery and treatment related research has been increased significantly in the recent years. Hence, the antibacterial, antifungal, and antioxidant activity potential of pre synthesized and characterized Titanium dioxide nanoparticles (TiO2 NPs) were investigated in this study through respective standard protocols. Interestingly, the obtained results revealed that TiO2 NPs have concentration dependent antibacterial activity against bacterial pathogens such as E. coli, P.mirabilis, V. cholerae, P. aeruginosa, S. typhimurium, and S. aureus at 100 µg mL-1 concentration. Furthermore, these TiO2 NPs showed remarkable antifungal activity against aspergillosis causing fungal pathogens such as A. niger, A. fumigatus, A. nidulans, and A. flavus at 100 µg mL-1 concentration. α-glucosidase. This TiO2 NPs also effectively inhibit the α-amylase (17%) and α-Glucosidase (37%) enzyme activity at 100 µg mL-1 dosage. The DPPH assay revealed that TiO2 NPs effectively scavenge DPPH free radicals by up to 89% at 100 µg mL-1 concentration, which was comparable to butylated hydroxytoluene (96%). These results suggest that the plant-based TiO2 NPs have remarkable in-vitro antibacterial, antifungal, and antioxidant activity. These may be considered for additional in-vitro and in-vivo experiments to assess their potential biomedical applications.

Larvicidal and pupicidal activity of phyto-synthesized zinc oxide nanoparticles against dengue vector aedes aegypti.

This study aimed to assess the phyto-synthesizing potential of Tarenna asiatica methanol leaf extract as well as its larvicidal and pupicidal potential against Aedes aegypti larvae. According to the findings of this study, the methanol leaf extract of T. asiatica has the potential to synthesize zinc oxide nanoparticles from zinc acetate dehydrate. Standard analytical techniques such as UV-visible spectrophotometer, Fourier-transform infrared spectroscopy, X-ray Diffraction analysis, Scanning Electron Microscope, and Energy Dispersive X-Ray were used to characterize the phyto-synthesized nanoparticles. The zinc oxide nanoparticles synthesized ranged in size from 22.35 to 31.27 nm and was spherical in shape. These nanoparticles demonstrated excellent larvicidal activity against Aedes aegypti larvae in the second, third, and fourth in stars, as well as significant pupicidal activity. These findings suggest that the methanol leaf extract of T. asiatica synthesized zinc oxide nanoparticles, which could be used to develop mosquito repellents.

Evaluation of cadmium tolerance and remediated efficacy of wild and mutated Enterobacter species isolated from potassium nitrate (KNO3) processing unit contaminated soil.

The purpose of this study was to find the most cadmium (Cd2+) tolerant and remediated bacteria isolate from KNO3 processing unit contaminated soil. One isolate out of 19 isolates possessed excellent Cd2+ tolerance than others, which was recognized as Enterobacter hormaechei SFC3 through molecular characterization (16S rRNA sequencing). The identified E. hormaechei SFC3 contained 55% and 45% of GC and AT content, respectively. The wild and acridine orange mutated E. hormaechei SFC3 exhibited excellent resistance to Cd2+ up to the concentration of 1500 µg mL-1. Furthermore, the wild E. hormaechei SFC3 and mutated E. hormaechei SFC3 showed 82.47% and 90.21% of Cd2+ remediation on 6th days of treatment respectively. Similarly, the Cd2+ tolerant wild and mutated E. hormaechei SFC3 showed considerable resistance to all the tested antibiotics. The findings indicate that E. hormaechei SFC3 isolated from KNO3 processing unit contaminated soil is a promising candidate for microbial remediation of Cd2+ contamination.

Optimistic influence of multi-metal tolerant Bacillus species on phytoremediation potential of Chrysopogon zizanioides on metal contaminated soil.

The current study investigated the plant growth promoting (PGP) characteristics of multi-metal-tolerant Bacillus cereus and their positive effect on the physiology, biomolecule substance, and phytoremediation ability of Chrysopogon zizanioides in metal-contaminated soil. The test soil sample was detrimentally contaminated by metals including Cd (31 mg kg-1), Zn (7696 mg kg-1), Pb (326 mg kg-1), Mn (2519 mg kg-1) and Cr (302 mg kg-1) that exceeded Indian standards. The multi-metal-tolerant B. cereus seemed to have superb PGP activities including fabrication of hydrogen cyanide, siderophore, Indole Acetic Acid, N2 fixation, as well as P solubilisation. Such multi-metal-tolerant B. cereus attributes can dramatically reduce or decontaminate metals in contaminated soils, and their PGP attributes significantly improve plant growth in contaminated soils. Hence, without (study I) and with (study II) the blending of B. cereus, this strain vastly enhances the growth and phytoremediation potency of C. zizanioides on metal contaminated soil. The results revealed that the physiological data, biomolecule components, and phytoremediation efficiency of C. zizanioides (Cr: 7.74, Cd: 12.15, Zn: 16.72, Pb: 11.47, and Mn: 14.52 mg g-1) seem to have been greatly effective in study II due to the metal solubilizing and PGP characteristics of B. cereus. This is a one-of-a-kind report on the effect of B. cereus's multi-metal tolerance and PGP characteristics on the development and phytoextraction effectiveness of C. zizanioides in metal-polluted soil.

Cobalt nanoparticles synthesizing potential of orange peel aqueous extract and their antimicrobial and antioxidant activity.

The ability of cobalt nanoparticles (CoNPs) to absorb electromagnetic waves led to their use as potential biomedical agents in recent years. The properties of magnetic fluid containing cobalt nanoparticles are extraordinary. Hence, this research was designed to evaluate the Co(NO3)2 reducing the potential of orange peel aqueous extract and assessed their antimicrobial and antioxidant activities. The aqueous extract derived from orange peel had the potential to fabricate the CoNPs from 1 M Co(NO3)2 and the synthesized CoNPs were successfully characterized by standard nanoparticles characterization techniques such as UV-vis spectrophotometer, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), and Dynamic light scattering (DLS) analyses. The FTIR analysis revealed that the synthesized CoNPs were capped with active functional groups. It was characterized by predominant peaks corresponding to carbonyl (CO), amide (CO = ), and C-O of alcohols or phenols. The size and shape of CoNPs were found as 14.2-22.7 nm and octahedral, respectively, under SEM analysis. Furthermore, at increased concentration, the CoNPs demonstrated remarkable antimicrobial activity against common bacterial (Escherichia coli, Staphylococcus aureus,Bacillus subtilis, and Klebsiella pneumoniae) and fungal (Aspergillus niger) pathogens. Furthermore, these CoNPs also showed considerable in-vitro antioxidant activities against various free articles such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), and Hydrogen Peroxide (H2O2). These results suggest that OP aqueous extract synthesized CoNPs possess considerable biomedical applications.