Determination of C vitamin and some essential trace elements (Ni,Mn,Fe,Cr) in bee products

摘要

During the last years,following the general trend of using what nature is directly offering,bee products got an increasing importance as essential natural resources in promoting healthy food.The objective of this study was to determine the ascorbic acid and the contents of trace essential elements (Cr,Fe,Mn,Ni).Ascorbic acid was first known to prevent scurvy.This disease is a rare clinical finding today.Yet,interest in ascorbic acid persists.Ascorbic acid is largely used in therapy as an anti-infections factor.It is essential to the normal functioning of cells.Ascorbic acid,C_6H_8O_6,is cleanly oxidized to dehidroascorbic acid by bromine.An unmeasured excess of potassium bromide is added to an acidified solution of the sample.The solution is titrated with standard potassium bromate to the first permanent appearance of excess bromine;this excess is then determined iodometrically with standard sodium tiosulfate.Instrumental method for the analysis of Cr,Fe,Mn and Ni in bee products is inductively coupled plasma atomic emission spectrometry (ICP-AES).The levels of Ni varied from 1.54 to 2.55 mg/Kg,Fe from 2.55 to 3.50 mg/Kg,Mn from 1.75 to 6.51 mg/Kg.Cr from 0.03 to 0.80 mg/Kg.