LAUSR

Introduction: Nanoparticles have attracted a lot of attention due to their special properties and potential applications which arise due to their large surface area and surface plasmon resonance (SPR) effect. Silver nanoparticles present a strong bactericidal effect and are known to be powerful antibiotics besides being used in anticancer and antiviral therapies. There is an increase in the resistance of bacteria to antibiotics attributed to the overuse and has become an area of concern which led to renewed interests in investigating the efficacy of silver nanoparticles as a potent alternative. Materials and Methods: 1 milli molar of silver nitrate solution in double distilled water was prepared initially. 1 mL of the Rosemary oleoresin was added with the metal solution and was made up to 100 ml. The colour change was observed visually and photographs were recorded. The solution was kept in magnetic stirrer for nanoparticle synthesis. The synthesised NP’s solution was preliminary characterised by using UV-vis-spectroscopy. Agar well diffusion method was used to determine the antibacterial activity of the rosemary oleoresin mediated silver nanoparticles. Different concentrations of rosemary oleoresin mediated Ag NP’s was tested against Staphylococcus aureus, Streptococcus mutans (gram +), and pseudomonas sp using muller hinton agar plates. Results and Discussion: It has been observed that the antibacterial effect of the prepared silver nanoparticles was almost similar against all the organisms used in the study. The maximum zone of inhibition (ZOI) was found against against Pseudomonas sp and minimum ZOI against Streptococcus mutans. It was also been observed that the antibacterial activity of the Rosemary mediated silver nanoparticles increased with increasing concentration. Conclusion: This study indicates, rosemary oleoresin can be used as an environment friendly and non-hazardous material for the synthesis of silver nanoparticles, thus aiding in the elimination of using hazardous reducing agents. The additional antimicrobial activity of rosemary oleoresin mediated silver nanoparticles increases its efficacy in the field of medicine.