Composição química de óleo essencial e hidrolato de folhas de Eugenia uniflora L.: uma análise comparativa

Abstract

Eugenia uniflora L. is a plant of notable medicinal potential, whose volatile products, such as the essential oil (EO), are widely studied, while its co-product, the hydrolate (HS), remains an underutilized resource despite evidence of its biological activity. In this context, the present study aimed to analyze and compare the chemical composition of the EO and HS obtained from the leaves of E. uniflora. The leaves, collected in São Lourenço D'Oeste-SC, Brazil, were dried and subjected to hydrodistillation to simultaneously obtain the EO and HS; the EO was analyzed directly, while the organic constituents of the HS were concentrated by liquid-liquid extraction with ethyl acetate, with both fractions being characterized by gas chromatography-mass spectrometry (GC-MS). The results indicated a yield of 0.46% for the EO, whose composition was a complex mixture of sesquiterpenes, with ³-cadinol (27.06%) and eudesm-7(11)-en-4-ol (26.16%) as major components, characterizing a distinct regional chemotype. In contrast, the analysis of the hydrolate extract showed a more selective chemical profile, with a significant dominance of the more polar sesquiterpene alcohols ³-cadinol (59.34%) and epi-³-muurolol (17.14%), in addition to non-terpenic oxygenated compounds absent in the essential oil. It is concluded that the hydrodistillation of E. uniflora fractionates its volatile metabolites into two distinct and valuable products: the essential oil, a concentrated and complex lipophilic matrix, and the hydrolate, a high-volume co-product rich in specific polar constituents such as ³-cadinol. This differentiation validates the HS not as a residue, but as a promising raw material with potential for industrial and therapeutic applications distinct from the essential oil, allowing for the complete utilization of the plant.