Systematic Evaluation of Antioxidant Efficiency and Antibacterial Mechanism of Bitter Gourd Extract Stabilized Silver Nanoparticles.

Kavya Moorthy,Po-Jen Yu,Cheng-Kang Chiang,Wen-Jui Wu,Kai-Chih Chang,Jun-Yi Hsu

doi:10.3390/nano11092278

Abstract

In this study, we accentuate the facile and green synthesis of ecologically viable silver nanoparticles (AgNPs) using aqueous (A-BGE) and ethanolic (E-BGE) dried bitter gourd (Momordica charantia) fruit extract as reducing and capping agents. Although AgNPs synthesized using BGEs have been reported earlier in fundamental antimicrobial studies, the possible antioxidant activity, antibacterial efficacy against superbugs, and a potential antimicrobial mechanism are still lacking. The characterization of as-prepared AgNPs was studied through UV-vis, TEM, Zeta-potential, FT-IR, XRD, and XPS analysis. The antioxidant ability of BG-AgNPs was extensively evaluated through DPPH and FRAP assays, which showed that A-BG-AgNPs possessed higher scavenging ability and superior reducing power due to the high phenolic content present in the BG extract. Furthermore, A-BG-AgNPs were highly stable in various physiological media and displayed excellent antibacterial activity against drug-resistant bacterial strains (i.e., MIC value of 4 µg/mL). The generation of reactive oxygen species evidenced that the possible antimicrobial mechanism was induced by BG-AgNPs, resulting in bacterial cell damage. Within the minimal hemolysis, the BG-mediated AgNPs possessed synergistic antioxidant and antibacterial agents and open another avenue for the inhibition of the growth of pathogens.

Highlights

IntroductionNanotechnology is an innovative field offering an opportunity to pioneer a method of treating microbial infection through nanoparticles [1]
The nanoparticles can act as antimicrobial agents, themselves, and as carriers for antibiotics with sustained, controlled bio-distribution with fewer side effects combating globally problematic multi-drug resistant (MDR) bacteria; they are typically termed as nanoantibiotics
While incubating AgNO3 with A-BGE and E-BGE at for 2 h, we found that a reddish-brown color of A-bitter gourd (BG)-AgNPs was synthesized using the 100 °C for 2 h, we found that a reddish-brown color of A-BG-AgNPs was synthesized

Summary

Introduction

Nanotechnology is an innovative field offering an opportunity to pioneer a method of treating microbial infection through nanoparticles [1] These nanomaterials, being ultrafine particles with specified physiochemical features rather than bulk materials that act as drug vectors fighting against drug-resistant pathogens, can exert multiple antibacterial mechanisms [2]. The nanoparticles can act as antimicrobial agents, themselves, and as carriers for antibiotics with sustained, controlled bio-distribution with fewer side effects combating globally problematic multi-drug resistant (MDR) bacteria; they are typically termed as nanoantibiotics They may be referred to as nanobactericides or nanocarriers depending on their action in terms of antibacterial activity, such as CuO, CeO2 , MgO, AgNPs, AuNPs, NiNPs, TiO2 , and ZnO, as per the literature.

Methods

Discussion

Conclusion