Purpose: To develop a simple and
precise method for the determination of the levels of
both essential and toxic elements in jujube collected
from different locations in China.
Methods: Dried jujube fruits
collected were digested by optimized microwave
procedure. Inductively coupled plasma atomic emission
spectrometry was employed to evaluate essential
elements, viz, calcium, magnesium, manganese, iron and
copper (Ca, Mg, Mn, Fe and Cu) and toxic elements,
namely, aluminum, lead and cadmium (Al, Pb and Cd) in
four jujube fruits.
Results: The results show that the
jujube fruits were rich in essential elements and had
low contents of toxic elements. The levels of the
elements varied significantly amongst the four jujube
fruits (p ˂ 0.05). Method validation indicates that the
proposed method was accurate and precision. The
detection limits were 0.0005 - 0.0100 µg/mL while
recovery ranged from 91.6 - 105.0%, with relative
standard deviation (RSD) ˂ 5%.
Conclusion: Five essential elements and
two toxic elements (except cadmium) varied widely in
their contents in the four jujube fruits. Knowledge of
the contents of these elements would provide consumers
with information on the quality of jujube fruits.
Keywords: Jujube fruits, Essential
and toxic elements, Microware digestion, Inductively
coupled plasma atomic emission spectrometry