Determination of the L-DOPA (L-3, 4-Dihydroxyphenylalanine) Content in Faba Bean (Vicia faba L.) Flowers and Faba Bean Flower Tea

Abstract

This study aimed to determine the L-DOPA content in the flowers of some different faba bean genotypes and determine the L-DOPA levels in tea prepared from flowers. The experiment was carried out under the ecological conditions in Samsun by the Black Sea with 15 genotypes using a randomized complete block design in three replications. The flowers were harvested three times and the number of flowers and flower yields were determined. The L-DOPA content of the flower and flower tea were determined using HPLC. Different solvents were used to extract the L-DOPA from the faba bean flowers. As a result of the HPLC analyses, the highest L-DOPA yield was determined to be in the tea samples brewed with hot water. It was found statistical differences between genotypes in the second and third harvests for the number of flowers in the plant and the total number of flowers. Dry flower yields ranged from 11.33 to 37.78 kg da−1 while L-DOPA levels were 6.2 to 9.17 g 100g−1 in dry flowers and 6.69 to 9.23 g 100g−1 in infused tea. The study concluded that flower tea of faba bean can be investigate for medicinal purposes and that L-DOPA in the plant can be extracted by brewing without requiring any solvent. This shows that L-DOPA is in a salt form within the plant.