Natural Products from Burseraceae: Chemical Diversity and Pharmaceutical Potentials

This study investigated the volatile chemical composition of the essential oil and hydrolate obtained from the resin of Protium heptaphyllum (Aubl.) Marchand (Burseraceae). Resin collected from material originating in Maranhão, Brazil, was subjected to hydrodistillation using a Clevenger-type apparatus. The process yielded 0.9% essential oil, and both the oily fraction and the corresponding hydrolate were analysed by gas chromatography coupled with mass spectrometry. The essential oil was characterised mainly by oxygenated monoterpenes, with α-terpineol (37.00%) as the predominant constituent, followed by carvone (10.85%), 1,8-cineole (9.24%), p-cymen-8-ol (7.75%), and trans-carveol (6.04%). The hydrolate also showed a predominance of oxygenated monoterpenes and related compounds, with α-terpineol (23.25%), p-cymen-α-ol (10.74%), carvone (9.12%), trans-carveol (7.43%), and 1,8-cineole (6.85%) among the main constituents. Several compounds were detected in both fractions, indicating partial partitioning during hydrodistillation, whereas other constituents occurred preferentially in either the essential oil or the hydrolate. The results demonstrate that the hydrolate is chemically distinct from the essential oil and should not be regarded simply as a diluted aqueous by-product. Instead, it represents a separate volatile fraction enriched in more polar constituents. These findings contribute to the phytochemical characterisation of P. heptaphyllum resin and provide comparative information on the distribution of volatile compounds between its essential oil and hydrolate.