STIMULATION OF SYNTHESIS AND RELEASE OF SWAINOSONINE FROM TRANSFORMEDROOTS OF SWAINSONA-GALEGIFOLIA

Transformed root cultures of Swainsona galegifolia were established fo r swainsonine production. Stimulation of production of swainsonine and its release into the culture medium was achieved using copper sulphat e, reduction of medium pH and supply of swainsonine precursors. The yi eld of control cultures (0.3 g of roots grown in 15 mi medium for 30 d ays) was 79 mu g swainsonine with only a trace of swainsonine in the m edium. After treatment with 1 mM copper sulphate for two days before h arvest on day 30, 155 mu g of swainsonine was produced, of which 14.3 mu g was in the medium. Reduction of medium pH from 5.7 to 2.7 for one day before harvest resulted in 159 mu g of swainsonine (47 mu g in th e medium). Supplementation with 2 mM malonic acid for 12 days before h arvest resulted in 187 mu g total swainsonine (34 mu g in the medium), while 2 mM pipecolic acid for six days before harvest gave the highes t swainsonine yield (220 mu g total, 43 mu g in the medium). The incre ased yields were achieved through small increases in biomass, as well as increases in the level of swainsonine synthesis.