Biologically active aliphatic acetogenins from specialized idioblast oil cells

More than three decades ago, Kashman and coworkers [1,2] reported for the f irst time a class of closely related compounds from avocados (Lauraceae). T his class of compounds contains several highly oxygenated long-chain acetyl enic and olefinic natural products derived from fatty acids (e.g. possibly C-18 oleic, linoleic, linolenic, or stearic acid as precursors). These prod ucts form part of a group of compounds known as the "biologically active al iphatic acetogenins", the distribution of which is thought to be restricted to the Annonaceae and Lauraceae. Current studies indicate that the Laurace ous acetogenins are synthesized during early plant development from special ized idioblast oil cells and transported from the oil cells to other parts of the plant. While idioblast oil cells are found throughout the plant kingdom, their fun ction in many plant families has been the focus of considerable speculation because little is known about the chemistry or biological activity of the oil in the cells. Until recently, the idioblast cells were generally viewed simply as unusual storage organs. In avocados, increasing evidence indicat es that the cells, and the oil they contain, may play an important defensiv e role against pathogens and insects. Several of the compounds produced in avocado oil cells, reported to occur almost exclusively in the genus Persea , are now known to have antibacterial, antifungal, and insecticidal activit y. In the present paper we review the distribution, synthesis, biological a ctivity, and mode of action of the most studied Lauraceous acetogenins: the diene persin, (12Z, 5Z)-1-acetoxy-2-hydroxy-4-oxo-heneicosa-12,15-diene, a nd the persin-derived furans known as avocadofurans.