A comparative study on the production of 3,4-dihydroxyphenylalanine (L-DOPA) was carried out in cell cultures of two Mucuna species by elicitor treatment and precursor feeding. The influence of elicitors and the precursor molecule on L-DOPA production, polyphenol oxidase (PPO) and tyrosinase activities was also studied. Callus cultures were initiated in Mucuna pruriens L. and Mucuna prurita H. on MS medium supplemented with BAP and IAA at different concentrations. Suspension cultures were established in MS liquid medium supplemented with BAP, IAA, the elicitors methyl jasmonate, chitin and pectin or the precursor L-tyrosine at different concentrations for L-DOPA production. Compared to the controls, several-fold increases in L-DOPA concentration were observed in elicitor-treated and precursor-fed suspension cultures of both plant species. L-DOPA concentrations were comparatively higher in precursor-fed cultures than those receiving elicitor treatments. A parallel increase in tyrosinase and PPO levels was also observed. Loss of cell viability was observed at high concentrations of elicitor-treated cultures, whereas L-tyrosine did not cause any cell death. Compared to elicitor treatments, precursor feeding resulted in higher concentrations of L-DOPA production and tyrosinase activity. The efficacy of L-DOPA production was found to be higher for suspension cultures of M. pruriens compared to M. prurita in all treatments.

Plant cell cultures provide an alternative means for producing secondary metabolites. The present study is an attempt to study the effect of some elicitors and precursor molecules on the production of L-Dopa (3, 4-dihydroxy-L-phenylalanine), which is a neurotransmitter precursor being used for symptomatic relief of Parkinson's disease. It is one of the most highly active allelochemicals present in Mucuna pruriens. Suspension cultures were established on Murashige and Skoog (MS) medium supplemented with 6-benzylaminopurine (BAP) and indole acetic acid (IAA). Elicitors such as methyl jasmonate, chitin, pectin, yeast extract and also a precursor L-tyrosine at different concentrations were supplemented to the suspension cultures at different concentrations, and their effect on L-Dopa production was studied. L-Dopa produced was quantified by high performance liquid chromatography (HPLC). Compared to the control set of suspension cultures a several-fold increase in L-Dopa concentration was observed in elicitors treated and precursor fed suspension cultures. Compared to elicitor treatments precursor feeding resulted in higher concentrations of L-Dopa production.

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