Maria Michela Salvatorea, Mohamed Mendilib, Monica Galloc, Daniele Naviglioa, Anna Andolfia, Marina Della Grecaa

aDipartimento di Scienze Chimiche, Università degli Studi di Napoli Federico II, 80126 Napoli, Italy;
bFaculty of Sciences, Plant, Soil, Environment Interactions Laboratory, University of El Manar, Campus Academia, 2092 Tunis, Tunisia;
cDipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, 80131 Napoli, Italy.

Lichens are symbiotic organisms combining fungi and autotrophic photosynthetic species (i.e. algae and/or cyanobacteria). They can grow in diverse and extreme environmental conditions, such as in very cold or very dry regions, at polar latitudes, or extreme altitudes. Lichens produce a great variety of secondary metabolites with various biological activities, including antimicrobial, antiviral, antitumour, antioxidant [1]. In this study, we investigate the secondary metabolites of Flavoparmelia caperata, a foliose lichen growing on trunks and branches of trees. The lichen samples were collected in Tunisia and submitted to extraction and chromatographic processes which led to the isolation of several bioactive secondary metabolites. The identification of lichen compounds including (+)-usnic acid, decarbousnic acid, chloroatranol, atraric acid, has been conducted essentially via GC-MS and NMR.

The objective of this study was to identify and characterize the principal bioactive compounds present in olive leaves derived from three distinct Olea europaea cultivars. The olive leaves were subjected to solid-liquid extraction, after which the analyses were conducted using high-performance liquid chromatography with photodiode array and mass spectrometry detection (HPLC-PDA-MS). This analytical method has previously been successfully employed by our research group for the characterization of drupes, olive oil, and related wastes [1]. The method was validated in terms of limit of detection (LoD), limit of quantification (LoQ), linearity range, reproducibility, and repeatability. The recovery of the method yielded satisfactory results.

Keywords: Secondary Metabolites, GC-MS, Chromatographic Purification

References

1. Calcott M.J., et al., Chemical Society Reviews, 47 (2018),  pag. 1730-1760. DOI: 10.1039/C7CS00431A