Bees could be dying because they lack a nutrient found in honey.
The western honeybee (Apis mellifera) adds billions of dollars to the global economy by pollinating crops, but a mysterious 'colony collapse disorder' has killed off many hives. Agricultural pesticides, overcrowding, frequent transport and bee parasites have all been blamed.
Work by May Berenbaum and her colleagues at the University of Illinois at Urbana–Champaign suggests another contributing factor: honey substitutes, which are often fed to bees by commercial beekeepers. The researchers used liquid chromatography to identify compounds in honey that activate the genes known to be upregulated by the foodstuff, then analysed gene expression in bees that were fed different diets. Those fed p-coumaric acid, a compound found in pollen, expressed more detoxification genes than bees given plain sugar syrup. Bees fed the pollen compound also produced higher levels of genes for antimicrobial peptides.
Proc. Natl Acad. Sci. USA http://dx.doi.org/10.1073/pnas.1303884110 (2013)