Determination of L-dopa (L-3, 4-dihydroxyphenylalanine) content of some faba bean (Vicia faba L.) genotypes

Abstract

Faba bean, reflecting all properties of legume crops such as soil improvement and benefit of human health, also contains L-dopa which can be used to cure Parkinson’s disease, is a rare plant. The study was conducted in Samsun province to determine the L-dopa content of leaf, flower and pod of faba bean genotypes. Four cultivars and 18 lines were sown on November in randomized complete blocks design with 3 replications. Samples were taken from leaves at vegatative period, flowers and fresh pods at generative period of faba bean. The L-dopa content was determined by HPLC. According to the result of variance analysis, the differences among genotypes for L-dopa content of flowers and fresh pods were found significant (P<0.01). L-dopa content of leaves, flowers and fresh pods varied between 10.88-33.41, 40.95-96.37; 4.16-52.28 mg kg-1, respectively. L-dopa content of flowers of 20 genotypes, except a cultivar and a line, were found in same group statistically. Avarage L-dopa content of leaf, flower and pod of faba bean were 19.36, 75.87 and 25.27 mg kg-1, respectively. The most common form of consumption of faba bean in Turkey and treatmet for Parkinson’s disease in some countries is fresh pod. However this study showed that L-dopa amount in flower is higher (P<0.01) than that of leaf and pod. Results of this study revealed that L-dopa content of 7 lines were richer than that of others. If agronomic characters of 7 lines are well, their potential to become a new variety should be investigated.