Conclusion

The biosynthesis of gold nanoparticles using the bacteria Rhodopseudomonas capsulata works as a great alternative to:

• Avoid contact of people that work in the extraction of gold with toxic and hazardous substances such as mercury and cyanide.
• Help to prevent contamination of water sources  and the affectation of people who depend of these sources.

This eco-friendly, efficient and simple method shows that is possible to do mining without affecting the environment.