The polyphenolic content of common lamiaceae species available as herbal tea products in Romanian pharmacies.

Unlabelled: The plants belonging to Lamiaceae family are widely used in medicine, cosmetic and food industry. Besides volatile oils, the main constituents of these plants are polyphenols. These compounds are secondary metabolites with multiple biological activities useful in the prevention and treatment of many disorders.
Aim: To determine the flavonoids. hydroxycinnamic acids and total polyphenols content in several aromatic Lamiaceae plants available in Romanian pharmacies as herbal tea products: Melissa officinalis, Lavandula officinalis, Rosmarinus officinalis, Mentha piperita, Thymus vulgaris and Salvia pratensis.
Material and Methods: The quantitative determination of different types of polyphenols was performed in ethanolic extracts 70% and 50%, respectively, of each sample, using spectrophotometric methods.
Results and Discussion: The total polyphenols levels in the investigated products ranged between 3.10% and 6.51% (expressed as g GAE/100 g dry weight), the largest amount being identified in Melissa officinalis (6.51%). The samples of Salvia pratensis and Mentha piperita were the richest in flavonoid derivatives expressed as g rutin/100 g dry weight (1.83% and 1.53%, respectively), the optimal extraction being with 70% ethanol. The highest content in hydroxycinnamic acids expressed as g rosmarinic acid/100 g dry weight was found in Melissa officinalis sample (4.15%).
Conclusions: There is a wide variability of polyphenolic content not only by species, but also depending on the polyphenols type or solvent used for extraction. The best extraction rate of total polyphenols in the investigated Lamiaceae species was obtained with 50% ethanol.