The invention discloses a method for extracting
levodopa by taking
mucuna cochinchine-sis(Lour)Tang et Wang as a
raw material. The method comprises the following steps: (1)
raw material pretreatment,(2) extraction, (3)
impurity removal, (4) concentration, (5) purification, (6) recrystallization, and (7)
drying to obtain a product. According to the method for extracting the
levodopa from the
mucuna cochinchine-sis(Lour)Tang et Wang as the
raw material, an acid solution adopts a mixed acid prepared from
formic acid and
hydrochloric acid according to a volume ratio of 1:(1 to 3), and can converttyrosine into dopa, thus greatly reducing the content of the
tyrosine in the product, and improving the quality of the product; resin is not needed in a preparation process, and generated
sewage andwastewater are less and easy to treat. The finished
levodopa prepared by the method is high in yield, the crude product yield is 4.0-4.5 percent, the product yield is 2.8-3.0 percent, and the contentof the
tyrosine in the prepared finished levodopa is reduced to 0.08 to 0.15 percent, and is reduced by 2 to 5 times compared with levodopa produced according to a conventional process.