”—” means that no relevant report data.
3.2.2 Trace elements in P. nagi kernel oil
The trace elements in this oil was confirmed using ICP-MS. Firstly, series of standard working solutions were successively measured to build the standard curve, and the regression equations were obtained accordingly. The regression equation, correlation coefficient and linear range of each element are shown in table 5 . The trace elements in this oil was tested accordingly and the contents were calculated according to the regression equations and the results also showed intable 5 . From table 5 , we can know thatP. Nagi kernel oil is rich in nine essential microelements beneficial to human health (it is reported that 18 kinds of essential microelements have been conformed as necessary to human health and life, namely, iron, copper, zinc, cobalt, manganese, chromium, selenium, iodine, nickel, fluorine, molybdenum, vanadium, tin, silicon, strontium, boron, rubidium, arsenic, etc.8).
Table 5. Regression equation, correlation coefficient (R) and detection limit
and the contents of trace elements in P. nagi kernel oil