ICP-MS测定木薯生产副产物的矿质元素和有害重金属元素

Application of ICP-MS to Detection of Mineral Elements and Heavy Metals in Cassava's Byproducts

木薯是我国广泛种植的热带作物，其块根富含淀粉，近年来常被用来生产燃料乙醇，是热门的生物质能源作物。木薯生产的同时产生了茎叶皮等大量副产物，长期以来被看成是废弃物，得不到充分的利用。木薯生产副产物含有很多营养成分，可以开发成高附加值的食品。采用ICP-MS技术对木薯生产副产物的矿质元素和有害重金属元素进行了研究，表明其含有丰富的人体必需矿质元素，大量元素的含量从高到低是K〉Ca〉P〉μg〉S〉Mn〉Zn〉Na〉Fe〉B〉Cu，尤其Fe，Mn，Zn和B含量达到10～800 μg·g^-1（DW，干重），微量元素Mo，Co，Se和Ge的含量均在0.01～0.2 μg·g^-1（DW）。除了上述有益矿质元素以外，副产物中重金属元素含量均达到国家标准，只是茎皮中Pb含量稍微偏高，达到2.19 μg·g^-1（DW）。

Cassava is a main cultivated tropical crop in China, its rich starch roots are often used to produce fuel ethanol in recent years, so it＇s a kind of hot biomass energy crops. But cassava＇s byproducts such as leaves, stems and peels are regarded as waste, and are not fully utilized. Cassava＇s byproducts contain many nutrients, and can be used to process high value food products. The contents of mineral elements and heavy metals in cassava＇s byproducts were studied by ICP-MS. The results showed that cassava＇s byproducts contained many elements necessary to human health, the sequence of macroelements was K〉Ca〉P〉 Mg〉S〉Mn〉Zn〉Na〉Fe〉B〉Cu, particularly, the contents of Fe, Mn, Zn and B ranged from 10 to 800 μg·g^-1（DW）, while the contents of microelements including Mo, Co, Se and Ge ranged from 0. 01 to 0. 2 μg·g^-1（DW）, which are important to human health. Besides maeroelements and microelements, the contents of heavy metals （As, Cr, Pb and Hg） were also important to identify the quality of farm products, and the results showed that cassava＇s byproducts contained little heavy metals except Pb （2.19μg·g^-1 （DW） in stalk peels）. All the data showed that eassava＇s byproducts accorded with the national hygiene standards.