CYTOTOXIC EFFECT AND ANTIOXIDANT ACTIVITY OF SILVER NANOPARTICLES SYNTHESISED USING HERBAL FORMULATION OF Ocimum sanctum AND Justicia adhatoda

Background: Nanotechnology is considered to be a new arena in the field of pharmacological research that has significant influence with varied applications in biomedical, engineering, chemical, drug and food industry. Silver nanoparticles have gained global attention, and one of the most exciting nanotechnologies is the use of microorganisms and herbal extracts for nanoparticle synthesis. Silver nanoparticles have huge potential in biomedical research for their multifaceted nature. Silver has been identified in many bacteria and microorganisms and they are found to they have an inhibitory effect on their growth and existence. Green synthetic methods for the development of nanoparticles have recently gained much interest in plant biotechnology. Biologically synthesized silver nanoparticles exhibit eco-friendly, low cost, one stage process and show greater benefit than chemical reductions. Many herbs exist in the Indian sub-continent which have varied medicinal values that have been used in the traditional medicines and for home remedies namely tulsi, chitharathai, adathoda, turmeric etc. Ocimum sanctum(tulsi)contains germicide and disinfectant, and Justicia adhatoda (adathoda) contains photochemical substances According to previous studies, Ocimum Sanctum (Tulsi) and Justicia adhatoda (adathoda) have an abundant of medicinal value which includes antifungal, anti-viral, antibacterial as well as cytotoxic properties.

Aim: This study aims at analyzing antioxidant and cytotoxic activity of silver nanoparticles mediated by herbal extract of Ocimum sanctum and Justicia adhatoda using UV Visible Spectroscopy.

Materials and Methods: Green synthesis of silver nanoparticles was achieved using Ocimum sanctum and Justicia adhatoda herbal extract prepared in our laboratory from a preexisting powder. Using UV- visible spectroscopy, the physical characterization like size and shape of these silver nanoparticles was confirmed and the cytotoxic and antioxidant activity was tested and characterized using UV- visible spectroscopy.

Results: The surface plasmon resonance band (SPR) was recorded at 450 nm. Antioxidant activity of nanoparticles also increased by increasing the concentration and cytotoxic activity was assessed using the number of live shrimps which also decreased by increasing concentration. The result showed the percentage inhibition of antioxidant activity at 50 mu/L and for cytotoxic activity at 25 mu/L.

Conclusion: Novellybiosynthesised silver nanoparticles using Ocimum Sanctum (Tulsi) and Justicia adhatoda (adathoda) exhibited a significant antioxidant and cytotoxic activity with minimal side effects. This is the first report of Tulsi and adhatoda mediated synthesis of silver nanoparticles showing such properties which have to be analysed further using other methods of characterization and testing.