Rosemary (Salvia rosmarinus Spenn. syn. Rosmarinus officinalis L.) is a Mediterranean aromatic species used both as an official herb and as a spice. Different cultivars may exhibit diverse phytochemical compositions, making a comprehensive chemical characterization pivotal for a targeted selection of valuable cultivars. This study aimed to characterize and compare the phenolic and terpene composition and content of leaf extracts of six Mediterranean rosemary cultivars: ‘Alba’, ‘Arp’ ‘Ginger’, ‘Gorizia’, ‘Tuscan Blue’, and ‘Roseus’. HPLC-DAD analysis revealed a similar phenolic composition in all the cultivars, but quantitative differences were observed. The main compounds were carnosic acid derivatives, flavonoids (e.g., luteolin, apigenin, and quercetin glucosides), rosmarinic acid, caffeic acid, and other hydroxycinnamic acid derivatives. The highest phenolic content was found in ‘Alba’, with a predominance of carnosic acid derivatives, whereas the lowest was found in ‘Ginger’ and ‘Gorizia’. The GC-MS analysis evidenced quantitative differences among the cultivars. Particularly, ‘Alba’ contained the highest terpene content, whereas ‘Arp’ and ‘Gorizia’ showed the lowest values. Regarding the antioxidant activity, ‘Alba’ exhibited the highest values as regards phenols, while for terpenes, the highest ones were obtained for ‘Ginger’ and ‘Tuscan Blue’. Significant Pearson correlations were obtained between the total phenol/terpene content and the antioxidant activity. The chemical characterization of these cultivars provides relevant information to produce the rosemary phytocomplexes, finding multiple industrial applications.

Background: 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.