A comparative study on phenolic components and biological activity of some <i>Senecio</i> species in Turkey

Abstract

OBJECTIVE: The phenolic components and biological activity of nine Senecio species growing in Turkey were investigated. METHODS: Senecio species were extracted with methanol. The content of total phenols was determined using Folin-Ciocalteu method, while individual phenolic acids and flavonoids were detected using HPLC analysis. Also, to determine the antioxidant capacity, phosphomolybdenum assay and 1,1-diphenyl picrylhydrazyl (DPPH) radical-scavenging activity assay were used. Antimicrobial activity of extract was determined using agar diffusion and broth microdilution method. KEY FINDINGS: The total phenolic contents of the extracts were found to be highest in Senecio cilicius and Senecio mollis extracts (117.45 and 113.40 mg equivalent to gallic acid/g, respectively). S. salsuginea showed the strongest free radical-scavenging activity with IC50 (the concentration providing 50% inhibition) = 26.23 μg/ml and S. mollis showed the highest antioxidant capacity in the phosphomolybdenum method (434.48 mg equivalent to ascorbic acid/g). The extracts exerted promising antibacterial activity against most of the test bacteria (minimal inhibitory concentration = 6.25-12.5 mg/ml), but no activity was observed against Candida albicans. CONCLUSION: The results demonstrated that nine Senecio species possess high antioxidant and antimicrobial activity in accordance with the high amount of phenolic contents in the extracts that might be natural agencies used in many areas such as food, pharmacy and alternative medicine.