Shoot organ cultures were established from callus derived from anthers of Hypercum perforatum flowers and the effect of elicitors oil hypericin and pseudohypericin production in shoot organ cultures was investigated. Mannan stimulated pseudohypericin production up to four fold (0.82 mg/g dry wt) and hypericin production up to two fold (0.04 mg/g dry wt). beta-1,3-glucan and pectin slightly stimulated pseudohypericin production (ca. two ford), but had no effect on hypericin production. On the other hand, yeast extract showed no stimulatory effect, on either hypericin or pseudohypericin production. (C) 2000 Elsevier Science Ltd. All rights reserved.