Alkaloid production by somatic embryo cultures of Corydalis ambigua

Abstract

Somatic embryos of Corydalis ambigua (Papaveraceae), which were cultured in liquid Linsmaier and Skoog medium supplemented with 0.1 µM IAA and 3% sucrose, produced two tetrahydroprotoberberine alkaloids, corydaline (0.03% of dry cell weight) and cavidine (1.09%). Among various plant growth regulators tested, two phenylurea derivatives, thidiazuron and N-(2-chloro-4-pyridyl)-N′-phenylurea enhanced the alkaloid production. Addition of 1 µM thidiazuron to the medium gave the maximum alkaloid content, 0.12% corydaline and 1.91% cavidine, after 21 days incubation. These results were compared with those from callus cultures and various intact organs. Corydaline and cavidine were accumulated in leaf, tuber and somatic embryos, whereas corybulbine was detected only in tubers. Callus cultures and immature seeds, which lack embryos, contained only trace amounts of these alkaloids, suggesting the necessity for organ differentiation for alkaloid production in C. ambigua.