Metal nanoparticular synthesis techniques essentially involve a reduction of metal ions to
convert them into nanoparticles. Reducing agents originate from natural and synthetic sources. Chemical
methods involve the application of synthetic agents that are not healthy and eco-friendly and thus,
there is a need for green methods. Green synthesis methods involve the reduction of metal ions using
plant-based extracts or phytoconstituents and microorganisms like bacteria, yeast, and fungi. These
methods have been found to be cost-effective, more efficient and eliminate the application of hazardous
chemicals. The phytoconstituents involved in the synthesis of metal nanoparticles are rich in polyols
and antioxidants, which in addition to reducing properties, also offer stabilization of formed nanoparticles.
Moreover, the size of nanoparticles can also be controlled based on the mechanism of reducing agent
involved therein. The present review is an attempt to highlight the methods of synthesis of metallic nanoparticles
with a special mention of applications of various natural antioxidants in their synthesis.