RP-HPLC Analysis of Anti-Parkinson’s Drug l-DOPA Content in Mucuna Species from Indian Subcontinent

Abstract

Genus Mucuna has tremendous value in the Indian Ayurveda, and the species have been used for the management of diseases including Parkinson’s disease. Unfortunately, species other than M. pruriens are neglected for scientific investigation. In the present study, quantification of anti-Parkinson’s drug l-DOPA content using HPLC from eighteen different Mucuna samples from Indian subcontinent comprising nine species, five varieties of M. pruriens and a commercial Mucuna powder from Zandu Pharmaceutical Ltd. (MZP) is carried out. Seeds of eighteen Mucuna accessions were analyzed for l-DOPA content using RP-HPLC. The l-DOPA content from different samples is compared with commonly used M. pruriens var utilis. Moreover, possible correlation of protein and carbohydrate with l-DOPA synthesis is hypothesized. The authors found varying l-DOPA content in different species and varieties; and higher l-DOPA containing species were M. macrocarpa (11.6 ± 0.21%), M. sanjappae (10.81 ± 0.2%) and M. atropurpurea (10.80 ± 0.1%). Some of the M. pruriens accessions contained higher level of l-DOPA including M. pruriens var hirsuta (10.2 ± 0.15%), M. pruriens var utilis (Manipur) (9.9 ± 0.15%) and M. pruriens var pruriens (Aurangabad) (9.41 ± 0.07 and 9.5 ± 0.12%). The species, M. gigentea had the lowest l-DOPA content (3.68 ± 0.17%). The strong correlation between l-DOPA and carbohydrate content (R2 = 0.7997) was observed, whereas insignificant correlation (R2 = 0.0277) between protein and l-DOPA content was observed. Higher anti-Parkinson’s drug l-DOPA-containing species were found from India which can be explored further for better extraction of this immense drug. The present study opens a new avenue for metabolite modeling in plant for commercial production of l-DOPA at industrial level.