水提法生产左旋多巴的工艺研究及优化

Study and Optimization on the Process for Producing L-dopa by Water Extraction

关键词:  猫豆  左旋多巴  生产工艺  PAM  废水减排  沉淀  正交试验

Key words:  Mucuna pruriens  L-dopa  extraction process  PAM  wastewater reduction  precipitation  orthogonal experiment

摘要:

为研究开发一种新的环境友好的、从猫豆中提取左旋多巴（L-dopa）的生产工艺，用弱酸性水将猫豆磨成水浆，常温下用聚丙烯酰胺（PAM）沉淀去除提取液中的固体颗粒，过滤，滤液煮沸后冷却至室温，再次用PAM沉淀去除热变性析出的蛋白和淀粉，过滤，滤液浓缩，析出L-dopa粗品；粗品用热稀HCl精制，即可得到L-dopa产品；采用L₉（3⁴）正交试验法优选关键工序的工艺参数。结果表明：工艺不排放高含淀粉、蛋白、HCl和NaOH废水。试产3批，平均每批投料猫豆200 kg，L-dopa产品平均得率2.41%，平均含量99.84%，与传统工艺相当；含量和相关物质符合《中国药典》和《欧洲药典》要求。该生产工艺合理可行，绿色环保，适合于工业化规模生产。

Abstract:

In order to develop a new environmentally friendly production process to extract L-dopa from Mucuna pruriens, Mucuna pruriens were grinded into water slurry with acidulous water, and the solid particles in the extract solution were removed by polyacrylamide (PAM) precipitation under room temperature. After filtration, the filtrate was boiled and cooled to room temperature. Once again, thermal denatured starch and protein were removed by PAM precipitation. After filtration, the filtrate was concentrated to release crude L-dopa. L-dopa product can be obtained by refining crude product with hot dilute HCl solution. L₉ (3⁴) orthogonal tests were used to optimized the process parameters of key processes. The results showed that the newly developed process did not discharge wastewater containing starch, protein, HCl and NaOH.3 batches were trial-produced with an average of 200 kg Mucuna pruriens per batch, and the average yield of L-dopa product was 2.41%, and the average content was 99.84%. The extraction efficiency was close to that of traditional process. The content and related substances meet the requirements of Chinese Pharmacopoeia and European Pharmacopoeia. The newly developed production process is green, reasonable and feasible, and suitable for the production of industrial scale.