中江丹参植株中镉、铅、铜的初级和次级形态分析

摘要

为了解丹参植株根、茎、叶中镉、铅、铜的初级和次级形态分布,该文测定丹参植株3种金属离子的含量,采用水煎提取分离初级形态,大孔吸附树脂、强酸性阳离子交换树脂、螯合树脂分别对水溶性金属离子及其结合物进行吸附分离,区分水溶有机态和无机态、游离态和非游离态、稳定态和不稳定态等次级形态.结果显示:3种金属在植株中的含量分布均为叶>茎>根,镉和铅溶出率超过50%,根中铜的溶出率为66%,但茎和叶中铜的溶出率仅为10%左右.对比植株的物质总溶出率20%~27%,3种重金属的溶出比例很高,因此丹参作为药材使用必须严格控制重金属的含量.镉的水溶无机态在50%左右、铅>50%、铜<50%.茎和叶中3种金属离子的游离态都超过50%.镉和铅的水溶不稳定态>50%,而铜<50%.丹参地上部分3种重金属含量都高于根中的含量,如果要利用地上部分,需要考虑在有效成分提取过程中降低重金属含量.从形态分析数据可知,离子交换法可有效去除地上部分提取物中的重金属.%In order to understand the primary and secondary speciation distribution of cadmium, lead and copper in roots,stems and leaves of Danshen plant,the contents of three kinds of metal ions in Danshen plant were determined. And then, the primary speciation of the metals were separated by water decoction and the secondary speciation, water-soluble organic and inorganic states, free and bound states, stable and unstable states, were differentiated by macroporous adsorption resin, cation exchange resin and chelating resin. The results showed that the concentration distribution of the three metals in the plants was leaf> stem> root. The dissolution percentage of cadmium and lead was more than 50% in all parts of plants,while the dissolution percentage of copper in the roots was 66% and in the stems and leaves was only about 10%. Compared with the total matter dissolution rate of Danshen being 20%-27%,the dissolution rate of the three heavy metals was very high. Therefore,the content of heavy metals in Danshen must be strictly controlled when the plant was used as the medicinal materials. The water-soluble inorganic speciation of cadmium was about 50%,and lead was greater than 50%,while copper was less than 50%. The water soluble free state of the three metal ions in stem and leaf was more than 50%. The water soluble unstable state of cadmium and lead was greater than 50%,while copper was less than 50%. The contents of the three heavy metals in the aerial parts of Danshen were higher than those in the roots. If the aerial parts were to be used,it was necessary to consider the reduction of heavy metal content during the extraction of active ingredients. From the specia-tion analysis data,ion exchange removal was an effective method.