The Antioxidant, Anticarcinogenic and Antimicrobial Properties of Verbascum thapsus L.

Background: The antioxidant, anticarcinogenic, and antimicrobial activities of Verbascum Thapsus L., known as great mullein, (an important medicinal plant containing different biochemical compounds including sesquiterpenes, flavonoids, saponins and lignins) were determined. There is not much data, to our knowledge, in this respect. Methods: The antioxidant activities of V. Thapsus were investigated by the DPPH (2, 2- diphenyl- 1-picrylhydrazyl) method. Using GC-MS, the presence of different anticarcinogenic products including 1-hexzanol (2.11%), 2-hexene (1.95%), etc. was determined in the ethanolic extract of V. Thapsus. The antimicrobial activities of V. Thapsus were determined by the minimum inhibiting concentration (MIC) and minimum bactericidal concentration (MBC) methods using the Grampositive and -negative bacterial strains. Results: The least concentration of V. Thapsus L. ethanolic extract (50 mg/l) resulted in only 21.26% inhibition of DPPH free radicals, however, the concentrations of 300 mg/l resulted in almost the highest inhibition (91.31%) of DPPH free radicals. The antioxidant activities of synthesized antioxidant BHT at the concentration of 300 mg/l or higher were similar to the antioxidant activities of V. Thapsus L. ethanolic extract. Both the isolated and the standard Gram-negative bacterial strains were more tolerant to the V. Thapsus ethanolic extract, compared with the Grampositive bacterial strains. Bacillus cereus was the most sensitive bacterial strain among the tested bacterial strains. Conclusion: The medicinal plant V. Thapsus L. can be used for the treatment of different diseases, such as cancer and infectious diseases.