Biological Activities of Sesquiterpene Lactones Isolated from the Genus Centaurea L. (Asteraceae).

In recent years, a growing interest has developed in the field of biological activity of plant metabolites. Research in this area considering antimicrobial, antioxidant, cytotoxic, anti-inflammatory, and other properties, is currently expanding, reporting various species to possess such biological effects. Among them, Centaurea species are well known to be used in ethnomedicine. The Centaurea genus (Asteraceae) is represented by more than 500 species, mostly located in the Mediterranean region and Western Asia.The current revision focuses on up-to-date literature on the isolation, structural elucidation and biological properties of sesquiterepene lactones from Centaurea species, regarding antimicrobial, antitumour, antiviral, anti-inflammatory and cytotoxic properties. The methods for extraction, isolation and identification are also pointed out and the bioactivity of lactones as purified compounds discussed. Several general ideas about the structural requirements for activity, based on the in vitro bioassays and the in silico prediction of their ADME properties are discussed.Investigations of chemical analyses and biological potential exhibited that flavonoids and sesquiterpene lactones, in particular germacranolides, eudesmanolides, elemanolides, and guaianolides, are compounds responsible for the biological potential of plants. Sesquiterpene lactones represent a group of compounds responsible for the medicinal characteristics of Centaurea species.Investigation of structure-activity relationships of all data helps the understanding of the bioactivity resulting from chemical aspects. All activities are discussed profoundly, paying special attention to molecular mechanisms involved in the implication of the health-beneficial effects of these compounds and in order to point them out as candidates for new drug discovery, and as safe natural agents.