Rendimento e composição do óleo essencial de patchouli (Pogostemon cablin) conforme o tempo de extração / Yield and composition of the patchouli (Pogostemon cablin) essential oil according to the extraction time

RESUMO

O patchouli possui óleo essencial nas folhas com utilização principalmente na indústria de perfumaria. O objetivo foi avaliar o melhor tempo de extração de óleo essencial de folhas secas de patchouli. Os tratamentos foram 1, 2, 3, 4, 5, 6, 7 e 8 horas de extração, através do método de hidrodestilação, com aparelho graduado do tipo Clevenger e balões com capacidade de 2 L.O delineamento foi inteiramente casualizado com três repetições. O material destilado foi seco à sombra até atingir aproximadamente 20% de umidade. Para cada tratamento, foram utilizadas amostras de 50 g de massa seca foliar. Foram avaliados o rendimento e a composição do óleo essencial. Não houve diferença entre os diferentes tempos de extração no rendimento de óleo essencial, podendo a extração do óleo essencial de patchouli ser realizada com uma hora de extração. O tempo de extração aumenta as porcentagens relativas do beta-guaieno (0,81%), beta-patchouleno (1,26%), alfa-selineno (1,37%), cariofileno (2,44%), alfa-patchouleno (3,08%) e gama-patchouleno (4,82%). O teor de pogostol (5,11%) reduz com o aumento do tempo de extração. O patchoulol, alfa-guaieno, alfa-bulneseno e seicheleno não sofrem influencia do tempo de extração.

ABSTRACT

Patchouli accumulatea an essential oil on its leaves, and it is mainly used by the perfume industry. The purpose of this work was to determine the distillation time for the extraction of essential oils from the leaves of patchouli. The treatments included 1, 2, 3, 4, 5, 6, 7 and 8 hours of extraction through the hydrodistillation method, using a Clevenger apparatus. The experimental design was completely randomized with three replications. The leaves were dried at room temperature until they reached 20% of humidity. The essential oil yield was measured from samples containing 50g of leaf dry mass. The essential oil production and composition were evaluated. No differences among the treatments were found on the essential oil yield, suggesting that the essential oil extraction can be carried out for 1 hour according to the experimental conditions. However, extending the extraction time, an increase in the relative percentage of beta-patchoulene (1.26%), cariofilene (2.44%), gamma-patchoulene (4.82%), alpha-patchoulene (3.08%), beta-guaiene (0.81%) and alpha-selinene (1.37%) was observed. The pogostol (5.11%) content was reduced with the increase of the extraction time. Patchoulol, alpha-guaieno, alpha-bulneseno and seicheleno contents were not affected by the evaluated extraction times.