Papain Mediated Synthesized Gold Nanoparticles Encore the Potency of Bioconjugated Flutamide

Fruit Derived Potentially Bioactive Bioengineered Silver Nanoparticles

INTRODUCTION

Protein-derived biogenic syntheses of inorganic nanoparticles have gained immense attention because of their broad spectrum of applications. Proteins offer a reducing environment to enable the synthesis of nanoparticles and encapsulate synthesized nanoparticles and provide them temporal stability in addition to biocompatibility.

METHODS

In the present study, Benincasa hispida fruit proteins were used to synthesize silver nanoparticles (AgNPs) at 37 °C over five days of incubation. The synthesis of AgNPs was confirmed by UV-Vis spectroscopy, TEM, zeta potential, and DLS analyses. Further, these NPs depicted antibacterial and antibiofilm effects. Additionally, the anticancer activities of nanoparticles were also tested against the lung cancer cell line (A549) with respect to the normal cell line (NRK) using MTT assay. Further, the estimation of ROS generation through DCFH-DA staining along with a reduction in mitochondrial membrane potential by Mito Tracker Red CMX staining was carried out. Moreover, nuclear degradation in the AgNPs treated cells was cross-checked by DAPI staining.

RESULTS

The average size of AgNPs was detected to be 27 ±1 nm by TEM analysis, whereas surface encapsulation by protein was determined by FTIR spectroscopy. These NPs were effective against bacterial pathogens such as Escherichia coli, Staphylococcus aureus, Salmonella enteric, and Staphylococcus epidermis with MICs of 148.12 µg/mL, 165.63 µg/mL, 162.77 µg/mL, and 124.88 µg/mL, respectively. Furthermore, these nanoparticles inhibit the formation of biofilms of E. coli, S. aureus, S. enteric, and S. epidermis by 71.14%, 73.89%, 66.66%, and 64.81%, respectively. Similarly, these nanoparticles were also found to inhibit (IC50 = 57.11 µM) the lung cancer cell line (A549). At the same time, they were non-toxic against NRK cells up to a concentration of 200 µM.

DISCUSSION

We successfully synthesized potentially potent antibacterial, antibiofilm and anticancer biogenic AgNPs.

A Survey on Analytical Methods for the Characterization of Green Synthesized Nanomaterials

Nowadays, nanotechnologies are well established and the uses of a great variety of nanomaterials show exponential growth. The development of green synthesis procedures experienced a great development thanks to the contribution of researchers of diverse origins. The versatility of green chemistry allows producing a wide range of organic and inorganic nanomaterials with numerous promising applications. In all cases, it is of paramount importance to carefully characterize the resulting nanomaterials because their properties will determine their correct performance to accomplish the function to which they were synthesized or even their detrimental effects like nanotoxicological behavior. This review provides an overview of frequently employed characterization methods and their applications for green synthesized nanomaterials. However, while several different nanoscale materials and their associated green construction methodology are being developed, other important techniques would be extensively incorporated into this field soon. The aim is to encourage researchers in the field to employ a variety of these techniques for achieving an exhaustive characterization of new nanomaterials and for contributing to the development of validated green synthesis procedures.

Antibacterial, anti-efflux, anti-biofilm, anti-slime (exopolysaccharide) production and urease inhibitory efficacies of novel synthesized gold nanoparticles coated Anthemis atropatana extract against multidrug- resistant Klebsiella pneumoniae strains

In this study, the antibacterial, anti-efflux, anti-biofilm, anti-slime (exopolysaccharide) production and urease inhibitory efficacies of green synthesized gold nanoparticles (AuNPs) coated Anthemis atropatana extract against multidrug- resistant (MDR) Klebsiella pneumoniae strains were evaluated. The green synthesized AuNPs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffractometer (XRD), particle size distribution, zeta potential and Fourier-transform infrared spectroscopy (FTIR). Then, antibacterial, anti-slime (exopolysaccharide) production, anti-biofilm and anti-efflux activities of AuNPs were investigated using micro-dilation, Congored agar, microtiter plate and MIC of ethidium bromide methods, respectively. Subsequently, the expression of mrkA, wzm and acrB genes was evaluated using quantitative Real-Time PCR (qRT-PCR). The synthesized AuNPs exhibited antibacterial activity against MDR strains of K. pneumoniae (minimum inhibitory concentration (MIC) of 6.25-50 µg/ml), as well as showed significant anti-slime (exopolysaccharide) production, anti-biofilm and anti-efflux activities against MDR strains. AuNPs showed significant inhibition against jack-bean urease and down-regulated the expression of mrkA, wzm and acrB genes. Moreover, the in vitro cytotoxic activity confirmed by MTT assay on the HEK-293 normal cell line showed negligible cytotoxicity. Thus, the present study suggests the potential use of AuNPs in the development of novel therapeutics for the prevention of biofilm-associated K. pneumoniae infections.