ADVENTITIOUS ROOT CULTURE AS A STRATEGY FOR ELICITOR-MEDIATED ANTHRAQUINONE PRODUCTION IN RUBIA CORDIFOLIA L

Abstract

Many plants, particularly those used in Indian systems of medicine, produce secondary metabolites to treat various ailments. The increasing demand for these phyto-compounds may threaten the existence of the plant itself. To meet future demands, improving production is essential. This can only be achieved through the application of modern biotechnological techniques, which require efficient, reproducible, and practical protocols. One such plant, Rubia cordifolia (Indian madder), is highly valued for its roots, known as 'manjishtha.' However, due to over-exploitation, the plant faces an imminent risk of extinction, which could severely impact its market supply in the near future.

The present study explores an in vitro approach to enhance the production of anthraquinones from adventitious roots as an alternative method for obtaining active metabolites. Elicitors such as Methyl Jasmonate (MeJA), Salicylic Acid (SA), Chitosan (CH), and Copper Sulphate (CS) were used to stimulate metabolite production. Among these, Copper Sulphate (CS) induced the highest accumulation of intracellular alizarin (52.05 mg/g dw) and extracellular purpurin (2.34 mg/g dw), which were approximately 2.75-fold and 2.39-fold greater than the control, respectively. Similarly, adventitious root cultures treated with 100 µM MeJA showed a 2.75-fold increase in intracellular alizarin (52.05 mg/g dw) and a 2.39-fold increase in extracellular purpurin (2.34 mg/g dw). 

This study shows that using adventitious root culture with the right elicitors can be an effective way to increase anthraquinone production in Rubia cordifolia. This method can help reduce the need to harvest the plant from the wild, making its use more sustainable in the future.