Sedative Effects of Latexes Obtained from Some Lactuca L. Species Growing in Turkey

L. species belong to the Asteraceae family and these plants are traditionally used for therapeutic purposes around the world. The dried milky latex of is known as "lettuce oil" and is used as a sedative in Turkey. This study aimed to evaluate the sedative effects and analyze the chemical compositions of latexes obtained from some species growing in Turkey. The sedative effects were evaluated through various behavioral tests on mice. For this purpose, latexes were obtained from Boiss., (L.) J. Presl and C. P, (Vis and Panćić) Boiss. and Kotschy ex. Boiss., L., and L. The latex from showed the highest sedative effects, whilst and latexes also displayed significant sedative effects compared to the control group at a dose of 100 mg/kg. However, the latexes from and did not exhibit any sedative effects on mice. Characteristic sesquiterpene lactones (lactucin, lactucopicrin, 11,13β-dihydrolactucin, and 11,13β-dihydrolactucopicrin) were determined qualitatively and quantitatively by high-performance liquid chromatography (HPLC). Lactucin was identified as the main component.