Driven by the growing interest in natural antioxidants for applications in the pharmaceutical and food industries, medicinal plants have become prominent candidates for the discovery of bioactive molecules. This study investigates the antioxidant properties and phytochemical composition of Aloysia citrodora (lemon verbena) through various extraction approaches. Leaves of the plant were subjected to Soxhlet extraction using two solvents of distinct polarity: methanol and hexane, yielding the Methanolic Extract (ME) and Hexane Extract (HE), respectively. The total phenolic and flavonoid contents were quantified using established colorimetric assays, confirming the richness of both extracts in antioxidant secondary metabolites. Antioxidant potential was assessed via the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay. The methanolic extract exhibited the highest free radical neutralization capacity (IC₅₀ = 0.024 µg/mL), outperforming the hexane extract (IC₅₀ = 0.812 µg/mL) and the essential oil (IC₅₀ = 1.771 µg/mL). Furthermore, GC-MS analysis of the hexane extract identified 15 volatile constituents, with major components including cis-Sesquisabinene hydrate (29.96%), Spathulenol (25.19%), α- Curcumene (13.06%), and Geranyl-p-cymene (4.95%). These findings highlight the significant antioxidant potential of Aloysia citrodora, particularly when extracted with methanol, and support its traditional use as a medicinal herb. The integration of phytochemical quantification, chromatographic profiling, and bioactivity evaluation provides a robust framework for future development in pharmaceutical and nutraceutical applications.
Maaroufi et al. (2025) studied this question.