Abstract
Background In this research, iron oxide nanoparticles were synthesized using Coleus amboinicus stem extract, which is used for various diseases such as throat infection, cough, fever, nasal congestion, and digestive problems. Aim This study aimed to formulate a green synthesis of iron oxide nanoparticles mediated by Coleus amboinicus (known as karpuravalli in Tamil) and assess its antimicrobial and antioxidant properties. Materials and methods Iron oxide nanoparticles were synthesized, and then their antimicrobial properties were tested against two specific pathogens, i.e., Streptococcus mutans and Candida albicans, using the agar well diffusion technique. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, hydroxyl radical scavenging (H(2)O(2)) assay, and ferric ion reducing antioxidant power (FRAP) assay were conducted to check the free radical scavenging activity. Result The results obtained showed that these iron oxide nanoparticles showed better antimicrobial activity against Streptococcus mutans when compared to Candida albicans, and the antioxidant activity showed a very close efficacy when compared to the standard. Conclusion The research has demonstrated the high antioxidant activity and high antibacterial activity of iron oxide nanoparticles using Coleus amboinicus stem, a natural and cheaper antimicrobial drug compared to the drugs present on the market.