Preliminary investigation on chemical composition and bioactivity of differently obtained extracts from Symphytum aintabicum Hub.- Mor. & Wickens

Symphytum species, commonly known as comfrey, hold a long history of folk medicinal uses for healing wounds, bone fractures and other pain resulting from inflammation. However, many species belonging to this genus have not yet been scientifically investigated and hence investigation in this regard is warranted. In the present research, S. aintabicum extracts prepared by different extraction techniques (homogenizer assisted extraction, infusion and maceration) were assayed for their chemosystematic attributes (total phenolic, flavonoid) as well as bioactive compound contents, antioxidant and enzyme inhibition potentials. For instance, the extracts were found to possess phenolic and flavonoid levels ranging from 35.50 to 112.25 mg GAE/g and 2.54–25.12 mg RE/ g, respectively. In general, the extracts displayed significant antioxidant activity. However, methanolic and infusion extracts were observed as the most potent radical scavengers and reducing agents, most likely related to their phenolic content. The extracts also showed metal chelating power and total antioxidant capacity in phosphomolybdenum assay. Moreover, while all extracts showed inhibition on amylase, only the methanolic extracts acted as inhibitors of cholinesterases and tyrosinase, most probably due to their relatively higher flavonoid content. The findings also indicated that the extraction method as well as the solvent type used to more or less affect the yield of the bioactive compounds and extracts’ bioactivity reported herein. Hence, as a first report highlighting the in vitro pharmacological properties of S. aintabicum, promising results were revealed from the quantitative chemosystematic analysis of bioactive components present and as sources of antioxidants and enzyme inhibitors against key human illnesses, thus providing scope for potential applications in phytomedicine development.