Abstract
NMR spectroscopy enables the study of complex mixtures, including plant extracts. The interpretation of specific ranges of 1H NMR spectra allows for the determination of polyphenolic compound, sugar, amino acid, and fatty acid profiles. The main goal of 1H NMR analyses of plant extracts is to identify the unique “fingerprint” of the material being studied. The aim of this study was to determine the metabolomic profile and antioxidant activity of various Lavandula angustifolia (Betty’s Blue, Elizabeth, Hidcote, and Blue Mountain White) and Lavandula × intermedia cultivars (Alba, Grosso, and Gros Bleu) grown in Poland. Modern green chemistry extraction methods (supercritical fluid extraction (SFE) and ultrasound-assisted extraction (UAE)) were used to prepare the lipophilic and hydrophilic extracts, respectively. The secondary metabolite profiles were determined using the diagnostic signals from 1H NMR and HPLC-DAD analyses. These metabolomic profiles were used to illustrate the differences between the different lavender and lavandin cultivars. The HPLC-DAD analysis revealed that both lavender species have similar polyphenolic profiles but different levels of individual compounds. The extracts from L. angustifolia were characterized by higher phenolic acid and flavonoid contents, while the extracts from L. × intermedia had a higher coumarin content. Diagnostic 1H NMR signals can be used to verify the authenticity and origin of plant extracts, and identify directions for further research, providing a basis for applications such as in cosmetics.