INDOLE ALKALOID PRODUCTION IN CALLUS-CULTURES OF UNCARIA-RHYNCHOPHYLLA (MIQ) MIQUEL

The effects of growth hormones and nutrients on growth and alkaloid pr oduction in callus cultures of Uncaria ia rhybchopylla (MIQ.) MIQUEL ( Rubiaceae) were investigated. Gamborg B5 (B5) medium supplemented with indoleacetic acid (10(-4) M) and 6-benzylaminopurine (3 x 10(-5) M) w as optimized both for the growth (1.8 g fresh weight/5 weeks) and alka loid production (1.73mg/g dry weight/5 weeks). The influence of sucros e concentration was examined, and 2% sucrose was found to be the most appropriate for the growth and alkaloid production. The effect of the composition of nitrogen sources was examined. Maximal growth and alkal oid production were obtained when 6 mM ammonium chloride and 25 mM pot assium nitrate were added to the B5 medium. Hirsuteine, hirsutine, 3 a lpha-dihydrocadambine and ursolic acid were isolated from the callus. The 3 alpha-dihydrocadambine concentration of callus was ca. 50-fold h igher than that of the hooks and stems of U. rhynchophylla.