Improved production of quinone-methide triterpenoids by Cheiloclinium cognatum root cultures: possibilities for a non-destructive biotechnological process

Quinone-methide triterpenoids (QMTs) derived from species of the family Celastraceae have long been used as anti-cancer, anti-inflammatory, anti-oxidant, anti-malarial and insecticidal agents. The main problem in producing QMTs on a large-scale from natural sources is the low amounts (<0.4% dry weight) produced by plants grown in vivo. The aim of this study was to compare the levels of QMTs accumulated by roots of Cheiloclinium cognatum cultured in vitro with those of in vivo plants aged 6 months to 10 years. The highest levels of QMTs produced by in vivo specimens were found in root bark of 10-year old plants, but in vitro cultured roots produced 3.52-times more 22β-hydroxy-maytenin and 11.46-times more maytenin. Most importantly, the cultured roots excreted QMTs into the growth medium, thereby facilitating the large-scale production, extraction and purification of these bioactive compounds by means of a continuous and non-destructive bioprocess that would preserve the root cultures.