Mucuna pruriens is the best known natural source of
L-dopa, the gold standard for treatment of
Parkinsonism. M. pruriens varieties are
protein rich supplements, and are used as food and fodder worldwide. Here, we report
L-dopa contents in seeds of fifty six accessions of four M. pruriens varieties, M. pruriens var. pruriens, M. pruriens var. hirsuta, M. pruriens var. utilis and M. pruriens var. thekkadiensis, quantified by HPTLC-densitometry.
L-dopa contents varied between 0.58 to 6.42 (%, dr. wt.). High and low
L-dopa yielding genotypes/chemotypes of M. pruriens could be multiplied for medicinal and nutritional purposes, respectively. HPTLC profiles of M. pruriens seeds on repeated extraction (24 h) in 1:1
formic acid-alcohol followed by development in
butanol:
acetic acid:water (4:1:1, v/v) showed consistent degradation of
L-dopa (Rf 0.34 ± 0.02) into a second peak (Rf 0.41 ± 0.02). An average of 52.11% degradation of
L-dopa was found in seeds of M. pruriens varieties. Since M. pruriens seeds and/or
L-dopa are used for treatment of
Parkinson's disease and as an
aphrodisiac both in modern and/or traditional systems of medicine, the finding of high level of
L-dopa degradation (in pure form and in M. pruriens extracts) into damaging
quinones and ROS is very significant.