Elicitor mediated adventitious root culture for the large-scale production of anthraquinones from Oldenlandia umbellata L.

Anthraquinones (AQs) have an increasing global demand due to its importance in both industrial and pharmaceutical fields. Increased demand can be met with large-scale production of the compound. Enhanced production of AQs was achieved through elicitor mediated adventitious root cultures of Oldenlandia umbellata L. Adventitious root cultures were raised by incorporating different auxins into the half strength MS liquid medium. The root cultures were incubated for a period of 60 days with continuous monitoring at 10 days interval. Among the different auxins used, 1 μM indole 3 acetic acid (IAA) produced highest amount of total AQ (11.09 mg g−1 dry weight). Later, for enhanced production of AQs, elicitors viz., yeast extract, pectin, xylan, or precursors like α-keto glutaric acid and L- phenylalanine and an AQ inhibitor, piroxicam were added at a concentration of 10, 25 and 50 mg L−1 to the medium on 35th day of incubation and roots were harvested at 40th day of incubation. Addition of 50 mg L−1 pectin resulted highest (24.33 mg g−1 dry weight) elicitation of AQs from adventitious roots. HPLC analysis of samples from adventitious roots confirmed the presence of alizarin in the extract. By adopting adventitious root culture through pectin (50 mg L−1) as elicitor, 2.19 fold enhanced AQ production over control was achieved in O. umbellata.