Essential Oil Composition and Antioxidant Capacity of Lippia schomburgkiana

Abstract

The leaves and fine stems of Lippia schomburgkiana recorded an essential yield of 1.8%, the main constituents of which were 1,8-cineole (64.1%) and α-terpineol (12.0%). The methanol extract of L. schomburgkiana inhibited the DPPH radical, resulting in an EC50 value of 16.1 ± 0.7 μg.mL−1, which is only three times lower than that of trolox (4.7 ± 0.4 μg.mL−1), signifying a high antioxidant activity for the species. The amount of total phenolics (376.7 ± 35.5 mg GAE/g) and the trolox equivalent antioxidant capacity (327.0 ± 24.8 mg TE/g) of the methanol extract confirmed the significant antioxidative capacity of this plant. The brine shrimp bioassay carried out on the oil (49.6 ± 0.4 μg.mL−1) showed high toxicity, providing important evidence of its biological activity. The sensory evaluation of the leaves of L. schomburgkiana showed a percentage acceptance value very close to commercial oregano, indicating that the plant can be used in spice and condiment products.