Qualitative and quantitative assessment of sesquiterpene lactones’ anticancer activities in wild and cultivated Achillea falcata -

Abstract

Cultivating medicinal plant species is an adequate strategy to meet the growing demand for a continuous supply. Achillea falcata, a plant endemic to the Middle Eastern region, is one of the most commonly used plants in Lebanese folk medicine. The main sources of bioactivity in this plant are the sesquiterpene lactones, which exhibit a high and selective potency against numerous cancer cells while sparing normal ones. The general aim of our project is to compare the anticancer properties and sesquiterpene lactones profile from wild versus cultivated species in order to promote the sustainable use of Achillea falcata. The plant was successfully cultivated at the Agriculture Research and Education Center facility of AUB. The aerial parts of both cultivated and wild Achillea falcata were fractionated using an acid-base extraction procedure. Plant extracts rich in sesquiterpene lactones were tested for their anti-proliferative properties against colorectal HCT-116, epidermal HaCaT II-4, promyelocytic leukemia HL-60, and Jurkat lymphoma human cancer cell lines. The concentrations that decrease the growth of cancer cells were determined using an MTT proliferation assay. The extracts were further fractionated using liquid chromatography. The collected subfractions were tested for their anti-proliferative properties and were further purified using preparative high performance liquid chromatography. Wild and Cultivated Achillea falcata exhibited the same profile of sesquiterpene lactones. However, the wild sources contained higher quantities of these secondary metabolites. In addition to the four secotanapartholides, namely 3-β-methoxy-isosecotanapartholide (1), isosecotanapartholide (2), tanaphallin (3), and 3-methoxy-8-hydroxy-isosecotanapartholide (4), three highly oxygenated guaianolides were isolated for the first time from Achillea falcata, namely Rupin A (5), Chrysartemin B (6), and 1β, 2β-epoxy-3β, 4α, 10α-trihydroxyguaian- 6α, 12-olide (7). These three newl