Rapid development of biosynthesis of metal nanoparticles using plants has attracted extensive interests to further investigate this novel and eco-friendly method. In the biosynthesis process

the plant may act as reducing agent

capping agent or shape directing agent. However

identifying specific roles of various components in the plant is challenging. In this study

we use biosynthesis of silver nanoparticles with Gardenia jasminoides Ellis extract to address this issue. The formation process of silver nanoparticles is investigated and the nanoparticles are characterized with the ultraviolet-visible spectroscopy

Fourier transform infrared spectra and scanning electron microscopy. The results indicate that the Gardenia jasminoides Ellis extract can reduce silver ions to form silver nanoparticles

stabilize the nanoparticles

and affect the growth of silver nanocrystal to form silver nanowires. Only geniposide in the extract exhibits good shape-directing ability for silver nanowires. It is found that bovine albumin is a potential capping agent

whereas rutin

gallic acid and chlorogenic acid possess reducing and capping ability.