不同工艺的树苔提取物中As的总量和形态

摘要

为了解不同工艺对树苔提取物中As的影响,采用ICP-MS、RP-HPLC-ICP-MS技术对不同提取、分离工艺制得的树苔提取物中As的总量和形态分布进行了分析.结果表明:①常规的乙醇复提、冷冻分离等操作,可以将树苔提取物中的As总量降低37%~49%;②不同溶剂提取的树苔提取物中,均未检测出砷胆碱(AsC);乙醇、乙醇-丙二醇和亚临界丁烷提取物中主要为As(III)和二甲基砷酸(DMA),水提取物中主要为As(V)和DMA;③乙醇和乙醇-丙二醇提取物在经过乙醇复提和/或冷冻分离等操作后,各种形态As的相对比例没有发生较大变化,只是As总量有所减少.水提取的树苔提取物在进行乙醇复提和冷冻分离后,As(V)减少的量大于As(III)和DMA,表明As(III)和DMA在乙醇中的溶解度大于As(V).%In order to study the effects of different extraction technologies on the arsenic measured in tree moss extracts, ICP-MS and RP-HPLC-ICP-MS were used to analyze the concentrations and species of arsenic. The results showed that: 1) The conventional procedures of alcohol re-extraction and freezing separation decreased the arsenic concentration by 37% to 49%. 2) AsC (Arsenocholine) was not detected in all the tree moss extracts extracted by different solvents. As(Ⅲ) and DMA (Dimethylarsenic acid) were the main arsenic species in the tree moss extracts extracted by alcohol, alcohol/propylene glycol and sub-critical butane, whileas As(Ⅴ) and DMA were the main species in those extracted by water. 3) After alcohol re-extraction and/or freezing separation, the proportions of arsenic species did not changed greatly, however the total arsenic decreased in the tree moss extracts extracted by alcohol and alcohol/propylene glycol. The concentration of As(Ⅴ) decreased much more than that of As(Ⅲ) and DMA in tree moss extracts extracted by water, which indicated that the solubility of As(Ⅲ) and DMA in alcohol was higher than that of As(Ⅴ).