From Ornamental Value to Antioxidant Activity: Comparative Phytochemistry of Lavandula Species and Cultivars

Lavandula (Lamiaceae) includes numerous species, cultivars, and hybrids widely cultivated for both their ornamental traits and for functional uses in perfumery, nutrition, medicinal, and cosmetic applications. Objectives: This study characterized the phytochemical profiles of three species (Lavandula stoechas L., Lavandula latifolia Medik., and Lavandula angustifolia Mill.), two cultivars (L. stoechas ‘Alba’ L. and L. angustifolia ‘Krajova’ Mill.), and the interspecific hybrid Lavandula × intermedia ‘Alba’ Emeric ex Loisel. Methods: All grown species and cultivars were maintained under uniform environmental and harvested simultaneously, to provide a comparative assessment of their terpene and polyphenol profiles and content, as well as their associated antioxidant activity. Results: HPLC-DAD/QTOF-MS analysis revealed differences in flavonoid and hydroxycinnamic acid content among species and cultivars. The main compounds identified were glycosylated derivatives of coumaric, caffeic, and ferulic acids, along with luteolin and apigenin derivatives. L. latifolia Medik. exhibited the highest hydroxycinnamic acid content (5.306 ± 1.265 mg/g FW), whereas L. stoechas ‘Alba’ L. showed the highest flavonoid concentration (2.537 ± 0.192 mg/g FW). GC-MS analysis indicated that hydrocarbon and oxygenated monoterpenes were the predominant terpene classes, with the highest levels recorded in L. stoechas L. (1922.09 ± 144.12 ng/g FW oxygenated; 945.89 ± 159.26 ng/g FW hydrocarbon monoterpenes). Antioxidant activity, assessed via DPPH and FRAP assays, was significantly correlated with flavonoid content across species, cultivars, and the hybrid. Conclusions: Intraspecific and interspecific variability within the Lavandula genus influences antioxidant activity and determines its suitability for different applications.