Supplementation with an Inorganic Iron Source Modulates the Metalloproteomic Profile of the Royal Jelly Produced by Apis mellifera L.

Abstract

This study aimed to evaluate the quality of the royal jelly produced by Apis mellifera bees in the presence of different iron concentrations (ferrous sulfate heptahydrate—0, 25, 50, and 100 mg L−1). Two-dimensional electrophoresis was used for the fractionation of royal jelly proteins, and iron level was quantified using flame atomic absorption spectrometry technique. The proteins were identified using electrospray ionisation mass spectrometry. Analysis of variance followed by the Tukey test (P < 0.05) was utilised. Dietary supplementation with mineral Fe affected the protein content and number of proteins in the experimental period. Further, the diet containing the highest iron concentration showed a greater number of spots containing iron, as well as in the abdomen of the bees. The most protein containing Fe were classified as major royal jelly proteins. These results showed that Fe influenced the quality of royal jelly and can improve its nutritional value.