Alkaloid Profile of Fifteen Different Species of Narcissus L. (Amaryllidoideae) Collected in Spain

Abstract

Molecular diversity is a key component of overall biodiversity, playing a vital role in evolution. It results from the adaptation of organisms to various habitats, which impacts their survival. The Amaryllidoideae subfamily is a significant group of monocotyledonous plants known for producing an exclusive and still-expanding group of molecules with diverse biological activities. Galanthamine (Gal), the most renowned metabolite from Amaryllidoideae subfamily, has been marketed for the palliative treatment of Alzheimer’s disease since 2001 due to its ability to inhibit the acetylcholinesterase enzyme. Due to the high cost and low yield of its synthesis, pharmaceutical companies extract this drug from Amaryllidoideae plants, such as Narcissus pseudonarcissus cv. Carlton in Europe and Lycoris radiata in China. The aim of this study was to describe the alkaloid profile of fifteen different species of Narcissus L. (commonly known as daffodils) collected in Spain using gas chromatography coupled with mass spectrometry. Fifty-one alkaloids were identified and quantified within these species through our private library of Amaryllidaceae alkaloids (AA) built over the last four decades, while thirty structures remained not identified in thirteen of these species. The highest concentration of these nitrogenate metabolites was quantified in N. confusus, 541 µg Gal·100 mg−1 DW, which also exhibited a notably high concentration of Gal, 301 µg Gal·100 mg−1 DW, which represents about 55% of the alkaloids identified in this species. The species N. bujei was also found to contain a significant quantity of this compound, amounting to 103.2 µg Gal·100 mg−1 DW. The plant N. assoanus harbored a total of seven unidentified compounds, indicating that this species could be a potentially important source of novel alkaloids. In conclusion, this study facilitates a direct comparison of alkaloid profiles for fifteen Narcissus plant species. This serves as a valuable tool for identifying possible new sources of galanthamine, as well as other novel medicinal alkaloids. Finally, this work presents the first alkaloid profile of the species N. minor and N. nevadensis.