Extração induzida de resina em duas espécies de Protium Burm f. e análise química do óleo essencial da resina em Protium strumosum Daly, na Reserva Florestal Adolpho Ducke - AM.

Abstract

Nowadays important products are collected from natural forests and there is a perspective for the discovery of new ones for national and international market. Studies to search for medicinal and aromatic properties in Amazon tropical forest’s biodiversity have increased. In genus Protium Burm f., some species exude an aromatic resin on their trunk, known generically as “breu”. These resins are widely used with a diverse of purpose by local people, have medicinal properties confirmed in studies and already are used in cosmetic industry. In this study it was tested a technique for extract the resin by making incisions in the bark of the trees and with the application of the stimulant ethephon (concentration 5%) in the cuts, in two species of Protium Burm f. that are found in abundance on Adolpho Ducke Forest Reserve - Central Amazon. In results was found that there were no exudation in the cuts only. The application of ethephon was promising in stimulate resin flow from the cuts, where the specie Protium strumosum Daly, with half number of trees (N=10), exuded a quantity much greater than the specie Protium hebetatum Daly (N=20), the productions were 785,79g and 86,55g respectively. The breast height diameter (BHD) showed weak correlation with resin production in the studied trees by regression analysis. To evaluate the possibility of obtain resin with similar composition, so a quality control can be made, the essential oil compounds of the resins in the ten trees of Protium strumosum Daly were analyzed. For evaluation of possible variation that ethephon could had caused in chemical composition of the resins, samples of natural exudation on five trees of Protium strumosum Daly were collected and had their volatile compounds identified for comparison with the resins colected by the use of ethephon. The Samples were submitted to extraction with hexane (solvent) and had their volatile compounds identified by gas chromatography with flame ionization detector (GC-FID) and gas chromatography coupled to mass spectrometry (GC-MS). The major compounds in most of the samples were the moterpenes α-pinene e α-phellandrene, and in some of them were found limonene, terpinolene and ρ-cimen-8-ol as principal compounds. In comparison of the ten trees from the same population by PCA, seven of them showed high similarity and three were different in their essential oil composition. In revision of the exsiccates of the trees, it was verified that in the three different ones there were a difference in the folioles comparing to the seven others, suggesting the existence of a sub-specie or variety of Protium strumosum Daly in Adolpho Ducke Forest Reserve, Central Amazon. Thus, it was verified that in seven Protium strumosum Daly trees was found high similarity of their essential oil composition. In comparison by principal component analysis (PCA) of the essencial oil composition of the natural exsudation resin and the collected by use of ethephon, the essential oils showed high similarity, only two variation appeared, but were not associated with the use of ethephon.