IN VITRO ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES OF SELECTED INDIAN SPICES AND HERBS

Kataria Roonal* and Surti A.

This study investigates the antioxidant and antimicrobial properties of ethanolic extracts and essential oils derived from eight commonly used Indian spices and herbs, including ajwain, fennel, bay leaves, coriander, dill (leaves and seeds), kalonji, and scallions. Phytochemical extraction was performed using Soxhlet and Clevenger methods, and antioxidant activity was assessed via DPPH radical scavenging assay. Antimicrobial efficacy was evaluated using disc diffusion, vapor phase, and microdilution methods against selected bacterial and fungal strains. Results revealed that ethanolic extracts generally exhibited stronger antioxidant activities than their essential oil counterparts, with ajwain and coriander showing the highest radical scavenging potential. Conversely, essential oils demonstrated broader antimicrobial activity, particularly those from fennel and ajwain, which inhibited both bacterial and fungal growth effectively. The vapor phase assay showed heightened sensitivity in fungal strains to essential oils, while MIC values indicated that ethanolic extracts were more efficient at lower concentrations. Ajwain emerged as the most potent spice in both antioxidant and antimicrobial assays, attributed to compounds such as thymol and carvacrol. The findings highlight the potential of these spices and herbs as natural preservatives and therapeutic agents, supporting their integration in food safety, cosmetic formulations, and alternative medicine.