Türkiye'de Tıbbi Çay Olarak Kullanılan Lamiaceae Familyasından Çeşitli Bitkilerin Fenolik Asit Miktarlarının ve Biyolojik Etkilerinin Araştırılması

Abstract

Many plants in the Lamiaceae family are widely consumed as herbal teas due to their aromatic properties and therapeutic potential. This study aimed to determine the content of rosmarinic acid and chlorogenic acid, two phenolic acids of high medicinal importance, using High-Performance Liquid Chromatography (HPLC) in aqueous infusions and 80% (v/v) ethanol extracts of twelve Lamiaceae species naturally growing or cultivated in Türkiye. Additionally, the antidiabetic potential of these extracts was evaluated using α-glucosidase and dipeptidyl peptidase-4 (DPP-4) inhibition assays, while their depigmenting potential was assessed through tyrosinase enzyme inhibition. According to the results, the highest rosmarinic acid content was detected in the 80% ethanol extract of Melissa officinalis (29.808 mg/g dry weight), whereas the highest chlorogenic acid content was determined in the 80% ethanol extract of Lavandula × intermedia (1.573 mg/g dry weight). In biological activity analyses, the aqueous infusion extract of Mentha × piperita exhibited the highest inhibition of the DPP-4 enzyme (44.379%), while the Melissa officinalis aqueous infusion demonstrated the highest inhibition of the α- glucosidase enzyme (>99% in all tested concentrations), displaying the strongest antidiabetic activity. Regarding tyrosinase enzyme inhibition, the highest activity was observed in the Salvia officinalis aqueous infusion extract, with an inhibition rate of 64.19%. The findings regarding high phenolic content and enzyme inhibition highlight the potential of Lamiaceae members as strategic natural raw materials and suggest that they should be supported by further research.