Thank you ZucchiniFlower. I am not aware of resaerch which indicates that Mucuna contains Cabidopa. Additionally, the research I have seen (pls see below) requires 30 gm of mucuna to equate with 200/50 Ld/Cd.
I am taking 1 teaspoon (<5 gm) twice daily. I am assuming that only a small percentage of L-dopa reaches the brain (hence a very mild effect on symptoms too I think!).
Actually my dose does not exeed the tradtional Indian medicine recommendation for Medicinal Properties: Action:
Herb - anthelmintic, aphrodisiac, astringent, nervine, tonic, rejuvenative.
Seeds - antihelmintic, astringent, nervine tonic, and an aphrodisiac
Root - nervine tonic, diuretic
Below is relevant paper :

Mucuna pruriens in Parkinson's disease: a double blind clinical and pharmacological study.Katzenschlager R, Evans A, Manson A, Patsalos PN, Ratnaraj N, Watt H, Timmermann L, Van der Giessen R, Lees AJ.
National Hospital for Neurology and Neurosurgery, London, UK.

BACKGROUND: The seed powder of the leguminous plant, Mucuna pruriens has long been used in traditional Ayurvedic Indian medicine for diseases including parkinsonism. We have assessed the clinical effects and levodopa (L-dopa) pharmacokinetics following two different doses of mucuna preparation and compared them with standard L-dopa/carbidopa (LD/CD). METHODS: Eight Parkinson's disease patients with a short duration L-dopa response and on period dyskinesias completed a randomised, controlled, double blind crossover trial. Patients were challenged with single doses of 200/50 mg LD/CD, and 15 and 30 g of mucuna preparation in randomised order at weekly intervals. L-dopa pharmacokinetics were determined, and Unified Parkinson's Disease Rating Scale and tapping speed were obtained at baseline and repeatedly during the 4 h following drug ingestion. Dyskinesias were assessed using modified AIMS and Goetz scales. RESULTS: Compared with standard LD/CD, the 30 g mucuna preparation led to a considerably faster onset of effect (34.6 v 68.5 min; p = 0.021), reflected in shorter latencies to peak L-dopa plasma concentrations. Mean on time was 21.9% (37 min) longer with 30 g mucuna than with LD/CD (p = 0.021); peak L-dopa plasma concentrations were 110% higher and the area under the plasma concentration v time curve (area under curve) was 165.3% larger (p = 0.012). No significant differences in dyskinesias or tolerability occurred. CONCLUSIONS: The rapid onset of action and longer on time without concomitant increase in dyskinesias on mucuna seed powder formulation suggest that this natural source of L-dopa might possess advantages over conventional L-dopa preparations in the long term management of PD. Assessment of long term efficacy and tolerability in a randomised, controlled study is warranted.

PMID: 15548480 [PubMed - indexed for MEDLINE]