Process byproducts from the fruit industry may represent a cheap and reliable source of green reducing agents to be used in current bio-nanosynthesis. This study reports the use of orange (Citrus × clementina) peel aqueous extract (OPE) for one-pot green synthesis of silver nanoparticles (AgNPs) with high effectiveness against various microbial pathogens as well as rat glial tumor C6 cells. The effects of various operational parameters on the synthesis of AgNPs were systematically investigated. The morphology, particle size, and properties of synthesized AgNPs were characterized using UV–visible spectroscopy, x-ray diffraction, x-ray photoelectron spectroscopy, field emission scanning electron microscopy, energy-dispersive x-ray spectroscopy, and Fourier transform infrared spectroscopy. High-resolution transmission electron microscopy shows that the nanoparticles are mostly spherical in shape and monodispersed, with an average particle size of 15–20 nm. Notably, the OPE-synthesized AgNPs were stable up to 6 months without change in their properties. Low doses of OPE-AgNPs inhibited the growth of human pathogens Escherichia coli, Bacillus cereus, and Staphylococcus aureus. The minimum inhibitory concentration and minimum bactericidal concentration of AgNPs against selected pathogenic bacteria were determined. OPE-AgNPs exhibited strong antioxidant activity in terms of ABTS (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) radical scavenging (IC50 49.6 μg/mL) and DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging (IC50 63.4 μg/mL). OPE-AgNPs showed dose-dependent response against rat glial tumor C6 cells (LD50 60 μg/mL) showing a promising potential as anticancer agents. Overall, the current investigation highlighted a cheap green technology route to synthesize AgNPs using OPE byproducts and could potentially be utilized in biomedical, cosmetic, and pharmaceutical industry.
Bibliographical noteFunding Information:
This research was supported by the Agricultural Research Center funded by the Ministry of Food, Forestry, and Fisheries, Korea. One of the author GK acknowledges Korea Research Fellowship Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (Grant No: 2016H1D3A1908953). The authors would like to thank Prof. Shrikrishna D. Sartale, Department of Physics, Savitribai Phule Pune University, India, for availing the HR-TEM facility. The authors are also thankful to Mr. Oh Sung-Taek, Dongguk University, for his technical help during anticancer studies.
© 2017, Springer-Verlag Berlin Heidelberg.
All Science Journal Classification (ASJC) codes
- Environmental Chemistry
- Health, Toxicology and Mutagenesis