Graduado

Sedative Effect of Monoterpene Alcohols in Mice: A Preliminary Screening
Damiao Pergentino de Sousaa,*, Ellen Raphaelb, Ursula Brocksomb, ˜ and Timothy John Brocksomb a b

Departamento de Fisiologia, Universidade Federal de Sergipe, CEP 49100-900 ´ ˜ Sao Cristovao-SE, Brazil. E-mail: [e-mail] ˜ ´ Departamento de Quımica, Universidade Federal de Sao Carlos, CEP 13565-905 ˜ Sao Carlos-SP, Brazil ˜

* Author for correspondence and reprint requests Z. Naturforsch. 62 c, 563Ð566 (2007); received January 17/March 12, 2007 Many essential oils and monoterpenes are used therapeutically as relaxing drugs and tranquilizers. In this study, ten structurally related monoterpene alcohols, present in many essential oils, were evaluated in mice to investigate their pharmacological potential in the central nervous system. Isopulegol (1), neoisopulegol (2), (ð)-isopinocampheol (3), (Ð)-myrtenol (4), (Ð)-cis-myrtanol (5), (+)-p-menth-1-en-9-ol (6) and (ð)-neomenthol (8) exhibited a depressant effect in the pentobarbital-induced sleep test, indicating a sedative property. (Ð)Menthol (7), (+)-dihydrocarveol (9), and (ð)-isoborneol (10) were ineffective in this test. The results show that these psychoactive monoterpenes have the profile of sedative drugs, and this pharmacological effect is influenced by the structural characteristics of the molecules. Key words: Sedative Effect, p-Menthane, Monoterpenes

Introduction Essential oils are natural products with many different applications, especially in the medical and cosmetic areas. The use of essential oils in the flavour and fragrance industry is well known, and their fragrances have been used in aromatherapy to induce mental tranquility or relaxation and to aid sleep in humans (Lavabre, 2001). In addition, many of them are found to exhibit varied biological properties, such as spasmolytic (Lis-Balchin and Hart, 1999) and anticonvulsant (Almeida et al., 2003) activities. These effects are probably due to the structural