Caffeic and rosmarinic acids in thyme species

Abstract

Hydroxycinnamic acids undoubtedly contribute to the wide range of pharmacological effects of the species of Thyme genus. Rosmarinic acid has antioxidant, hepatoprotective, cardioprotective, nephro-protective, anti-inflammatory, immunomodulatory, anti-allergic and anti-tumor properties. Caffeic acid has the antimicrobial, fungistatic activity, produces a choleretic effect. Accumulation of these acids is specific for Lamiaceae family. The aim of our research was to determine the type of hydroxycinnamic acids, the concentration of rosemarinic and caffeic acids and the total content of hydroxycinnamic acids, also to determine parameters of perfect extraction of this type of biological active compounds in the herb of four species of Thyme genus of the European flora. Identification of hydroxycinnamic acids has been carried out using paper and thin layer chromatography in different systems of solvents in comparison with standard compounds. Using TLC and HPLC caffeic and rosmarinic acids have been identified in the herb samples of Thymus Marshallianus, Thymus pulegioides, Thymus crenulatus, Thymus dimorphus. The results of HPLC analysis of caffeic and rosmarinic acids in the herb of Thymus species show that the concentration of rosmarinic acid ranges from 2343.40 mg/kg to 14351.74 mg/kg; the content of caffeic acid ranges from 74.41 mg/kg to 93.86 mg/kg. The highest concentration of rosmarinic acid, as well as caffeic acid was in Thymus pulegioides. The total content of hydroxycinnamic acids has been determined by spectrophotometry, and it ranges from 3.27 to 19.28%. Thymus crenulatus is the richest species by accumulation of the total content hydroxycinnamic acids. The optimal parameters for herb extraction such as the size of the crushed herb particles, extragent and extraction time have been found.