Enhanced accumulation of anticancer compounds in C. roseus hairy root cultures through elicitation and precursor feeding

Catharanthus roseus is a medicinal plant known for producing numerous indole terpenoid alkaloids. This study investigated the effects of methyl jasmonate, yeast extract, tryptophan, and tryptamine on the accumulation of four key alkaloids—ajmalicine, catharanthine, vincristine, and vinblastine—in hairy root cultures of C. roseus. Additionally, the expression levels of two biosynthetic genes, tryptophan decarboxylase (TDC) and strictosidine synthase (STR) were analyzed to explore potential transcriptional responses to elicitation. All concentrations of methyl jasmonate (MeJA) increased the levels of ajmalicine and catharanthine, while MeJA (10 and 250 µM) increased the levels of vinblastine. In contrast, yeast extract (YE) generally suppressed all indole alkaloid production. Tryptophan (TRPh) (50 mg/l) enhanced the production of catharanthine and vinblastine, while tryptamine (TRM) (100 mg/l) enhanced the production of vinblastine. Gene expression analysis revealed that methyl jasmonate (10 and 100 µM), tryptophan (50 and 250 mg/l), and tryptamine (100 mg/l) upregulated TDC and STR expression, whereas yeast extract downregulated these genes. These findings demonstrate that elicitor and precursor treatments can modulate both metabolic output and transcriptional activity in C. roseus hairy roots, providing useful insights for optimizing the in vitro production of anticancer compounds.