The chemical synthesis of nano particles may involve harmful chemicals which may be toxic towards humans and the environment. Hence, different techniques for the manufacture of nanoparticles through environmentally friendly methods have grown in leaps and bounds in the last few years. Plectranthus amboinicus has been used for many years as ayurvedic medicines for treating bacterial infections. Herein, the green synthesis of different transition metal-based nanoparticles will be discussed, utilizing phytochemicals from P. amboinicus. In addition, their spectroscopic analysis, with the help of UV-Vis and FTIR spectroscopy, as well as XRD techniques will be discussed. The utility of these biogenic nanoparticles has been based on their effectiveness on the restriction of bacterial growth. Each of the nanoparticles were tested against multiple bacteria, for example, Gram-negative E. coli and Klebsiella pneumonia as well as Gram-positive Streptococcus aureus and Bacillus subtilis. The zone of inhibition found for each bacterium was used as the criteria for measuring the effectiveness of the antibacterial nanoparticles.