Faustino, M., Seca, A.M.L., Silveira, P., Silva, A.M.S., Pinto, D.C.G.A. (2017) Gas chromatography–mass spectrometry profile of four Calendula L. taxa: a comparative analysis.Industrial Crops and Products, 104, 91-98. DOI:10.1016/j.indcrop.2017.04.029 (IF2016 3,181; Q1 Agronomy)
Calendula L. (Asteraceae) is a very interesting but unexplored genus mainly on a molecular level. The present study focus on four taxa of this genus: C. officinalis, C. arvensis, C. suffruticosa subsp. algarbiensis and C. suffruticosa subsp. lusitanica. The hexane extracts were analyzed by GC–MS, a useful tool for systematic biology and bioinformatics data, leading to the identification of 63 compounds. At a molecular level, pyrrolizidine alkaloids (41.5%), carboxylic acid derivatives (18.1%), carbohydrates (17.3%) and terpenoids (16.4%) were the most abundant chemical families found in C. officinalis. Regarding C. arvensis, supremacy of carbohydrates (30.7%), terpenoids (27.9%), and carboxylic acid derivatives (27.4%) were observed. In C. suffruticosa subsp. lusitanica, pyrrolizidine alkaloids (45.9%), terpenoids (19.3%) and carboxylic acids (18.0%) were the main detected chemical families whereas in the case of C. suffruticosa subsp. algarbiensis, pyrrolizidine alkaloids (26.7%), terpenoids (25.1%), alcohols (19.5%) and carbohydrates (16.6%) were the most abundant. The chemical characterization of the two C. suffruticosa subspecies is herein reported for the first time. Additionally, several carbohydrates, terpenoids, fatty acids and pyrrolidizine alkaloids are also being described for the first time in the genus Calendula and can be used in the genus taxonomic clarification. Despite the similarity in the main components a differentiation between the taxa was recognized through principal component analysis (PCA), that is the studied species can be differentiated at their molecular level.