<jats:title>ABSTRACT</jats:title><jats:sec><jats:title>Introduction</jats:title><jats:p>Dibenzylbutyrolactone‐type lignans are the physiologically active constituents of the achene fruits of Cynareae. These lignans occur in glycoside/aglycone forms: in the highest quantity of the arctiin/arctigenin, matairesinoside/matairesinol and tracheloside/trachelogenin pairs found in the fruits of <jats:italic>Arctium lappa</jats:italic> L., <jats:italic>Centaurea scabiosa</jats:italic> L. and <jats:italic>Cirsium arvense</jats:italic> (L.) Scop.</jats:sec><jats:sec><jats:title>Objective</jats:title><jats:p>To optimise the extraction yield of the arctiin/arctigenin, matairesinoside/matairesinol and tracheloside/trachelogenin glycoside/aglycone pairs, from the fruits of <jats:italic>Arctium lappa</jats:italic>, <jats:italic>Centaurea scabiosa</jats:italic> and <jats:italic>Cirsium arvense</jats:italic>, under the ripening, germination and enzymatic hydrolysis processes of the fruits.</jats:sec><jats:sec><jats:title>Methodology</jats:title><jats:p>Identification and quantification of lignans were performed with on‐line gas chromatography–mass spectrometry (GC‐MS) and with high performance liquid chromatography (HPLC), both with UV and mass selective detections (HPLC‐UV/MS).</jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>As novelties to the field it was confirmed that: (i) the unripe fruits provide a high amount of lignans, similar to the ripe fruit; (ii) the fruits of <jats:italic>Arctium lappa</jats:italic> and <jats:italic>Cirsium arvense</jats:italic> do have glycosidase activity to hydrolyse their lignan glycosides into free lignans; (iii) the glycosidase of <jats:italic>Centaurea scabiosa</jats:italic> fruit becomes activated under its germination process only; and (iv) the overwhelming part of the fruits lignan contents (80–94%) in all three species are accumulated in the embryo.</jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>The best sources of (i) lignan aglycones are the enzyme‐hydrolysed embryos, separating spontaneously during the germination process, and (ii) lignan glycosides are the unripe fruits. Copyright © 2012 John Wiley & Sons, Ltd.</jats:sec>