Polyphenols content of selected medical plants and food supplements present at Bulgarian market

Background: Medicinal plants are a rich source of antioxidant polyphenols and in particular flavonoids. Materials and methods: In the present study 5 Bulgarian medical plants and 5 food supplements, present at the Bulgarian market, are analyzed for their Total phenolic, Total flavonoids and selected individual flavonoids content. A HPLC method was developed and validated for simultaneous determination of (+)-catechin, (-)-epicatechin and rutin in plant and supplements, using PDA detection. Results: The results show that polyphenols in the selected food supplements are lower than those of the medical plants analyzed. Mentha piperita and Melissa officinalis have the highest polyphenols content (67.38 and 65.17 mg GAE/g; 54.59 and 57.76 mg RE/g respectively). Rutin was detected in all samples analyzed, reaching highest levels in Mentha piperita (7332.5 µg/g), followed by fruits of Sambucus nigra (2818.7 µg/g). Conclusion: The results of the study are a practical contribution to a more complete characterization of the polyphenolic composition in Bulgarian medicinal plants