Biological evaluation of wild thyme (Thymus serpyllum)

The present study assessed the different biological activities of the methanol extract of Thymus serpyllum L. (Labiateae) using bench top bioassays including brine shrimp cytotoxic, antitumor, antimicrobial, and phytotoxicity bioassays. Plant extract showed highly significant (ED50 466 ppm < 1000 ppm) impact on percentage death of brine shrimp. Agrobacterium tumefaciens (At-10)-induced tumors in potato disc tissue were inhibited (P < 0.05) significantly by methanol extract with no activity in antibacterial assay against Agrobacterium tumefaciens. EC50 value remained as 28.7 and 261.1 ppm for 12 days and 21 days of incubation respectively. Moderate antifungal activity (41-51%) was seen against five strains of fungus and no activity against any of the bacterial strain tested. Phytotoxicity to Lemna minor L. (P < 0.05) and radish seed germination and growth (P < 0.05) was observed at higher concentrations of the plant extract.