Encapsulated activated charcoal as a potent agent for improving taxane synthesis and recovery from cultures

The ability of a potent hydrophobic adsorbent, AC (activated charcoal), to induce total taxane synthesis and to improve the recovery of the products from suspension culture of Taxus baccata L. was examined. The results strongly showed that the application of encapsulated AC as an adsorbent not only led to improvement of in situ recover but also led to enhancement in taxane synthesis within the cells as well as having no inhibitory effects on the cell growth. The maximum yields for 10-deacetyl baccatin III, baccatin III and taxol were achieved by adding 1 g.l-1 adsorbent as alginate beads to the culture and culturing for 21 days and these were 3.5-, 4- and 2-fold respectively of that for the control. We demonstrated that the late exponential phase of the cell growth (day 14) could be the best time to add the adsorbent for maximizing the yield of taxol. Adding 1 g.l-1 AC resulted in maximum extracellular taxol (5.584 mg.l-1); this value was 2.19-fold higher than that in the control. According to the present results, AC is a powerful adsorbent that efficiently adsorbs the taxane compounds from a medium. We suggested that encapsulated AC could be used as a promising adsorbent agent for large-scale taxane production when it is added in combination with proper elicitors.