ICP-OES法分析桑椹果实成熟过程中14种矿物元素含量的变化

桑椹果实在成熟过程中各种成分不断发生变化，但对期间矿物元素的变化了解甚少。文章以桑椹果实为材料，采用电感耦合等离子体-原子发射光谱(ICP-OES)法对绿色期、粉色期、红色期、黑色期四种不同成熟度桑椹果实的九种必需元素和五种重金属元素含量进行了测定。结果发现，随着果实成熟度的增加，Na，K，Ca，Mg，Fe，Zn，Mn和Cu等元素的含量均出现明显的下降趋势，绿色期桑椹果实中上述各种元素的含量分别为2.99，2 957.49，809.00，559.95，36.30，10.07，2.12和1.32 mg·kg-1,而粉色期上述各种元素的含量下降了62.9%(Zn)至12.3%(Na)，红色期上述各种元素的含量分别降至1.63, 2 367.13, 489.30, 221.54, 19.01, 2.64, 0.40和0.59 mg·kg-1,黑色期果实各种元素的含量保持继续下降的趋势，但幅度大大减小。Se元素的含量绿色期最高，为1.24 mg·kg-1,粉色期下降，红色期上升至0.88 mg·kg-1,而黑色期又下降为0.65 mg·kg-1。重金属元素中Pb含量在前三个成熟时期变化不显著，而黑色期大大下降，绿色期最高为0.27 mg·kg-1,未超出国家标准。Cr含量随着果实成熟度的增加而增加，但黑色期又降至粉色期的水平，虽然红色期为54.07 mg·kg-1,但仍未超出国家标准。文章通过测定不同成熟时期桑椹果实的矿物元素含量，为果实采收时期的确定提供理论依据，也为桑椹果实的功能评价和安全评价提供参考数据。

Analysis of 14 Minerals of Mulberry Fruit in Different Mature Stage by ICP-OES Method

In the present study, the contents of nutritional elements such as Na, K, Ca, Mg, Fe, Zn, Se, Mn and Mo and heavy elements such as Cu, Cd, Pb, Cr and Co of mulberry fruits in three different mature stages were analyzed by ICP-OES. The results showed that the contents of Na, K, Ca, Mg, Fe, Zn, Mn and Cu decreased with maturation development. The contents of the above mentioned mineral elements in green stage were 2.99, 2 957.49, 809.00, 559.95, 36.30, 10.07, 2.12 and 1.32 mg·kg-1, respectively, their contents in pink stage were 169%（Zn）to 14%（Na）lower, the contents of these elements in red stage were 1.63, 2 367.13, 489.30, 221.54, 19.01, 2.64, 0.40 and 0.59 mg·kg-1, and the same changing trend remained in black stage, but the difference was much smaller. The content of Se was the highest in green stage (1.24 mg·kg-1), decreased in pink stage, increased in red stage (0.88 mg·kg-1), but decreased to 0.65 mg·kg-1 in black stage. There was no significant change in Pb content in the first three stages, but a substantial decrease occurred in black stage, and the highest content of Pb was 0.27 mg·kg-1 in green stage. The content of Cr increased during ripening, which was 54.07 mg·kg-1 in red stage, but in black stage it decreased to the same level as that in pink stage. Both the Pb and Cr contents were not over allowance of Chinese National Standard. These data can be well reference for harvesting stage design and evaluation of function and safety of mulberry fruits.