A study just published in the Proceedings of the National Academy of Sciences helps explain why honey is better food for bees than sugar water or high fructose corn syrup.
The study found several compounds in honey that enhance the bees’ ability to detoxify acaricides and pesticides, as well as produce more antimicrobial compounds that fight pathogenic bacteria.
The compounds evaluated, (primarily p-coumaric acid, a constituent of pollen cell walls) enable the bees to produce more of the detoxification enzymes known as CYP P450s. While most insects produce over 80 of these detoxifying compounds, the honey bee genome contains only 46 genes that code for P450 enzymes. That means honey bees have a limited arsenal relative to other insects for dealing with environmental toxins.
Specifically, the study found that 12 of these detoxification enzymes were induced (production was ramped-up) by p-coumaric acid.
To determine if this increase has any real-world significance, a treatment group of bees was fed bee candy laced with p-coumaric acid at a concentration roughly double that found in some pollens and bee breads, while a control group just got candy. These two groups were then fed equal amounts of the acaracide coumaphos. After 3 days, the midguts of the bees from both groups were dissected and assayed for the presence of the enzyme that metabolizes coumaphos. The treatment group (the one that got the p-coumaric acid) produced the coumaphos metabolizing enzyme at a rate about 60 percent higher than the control group.
The paper also identified 3 other compounds in honey that ramp-up production of the detoxification enzymes, and (fortunately for us here in the piedmont) the study notes that these compounds are abundant in the bud exudates of tulip poplar trees.
While we already know that honey is the best food for bees, it’s nice to see some research that sheds some light on exactly which compounds are involved.
Here’s a link to the abstract. I paid $10 to get the complete study, so if you are interested let me know.
http://www.pnas.org/content/early/2013/ ... 0.abstract
Paul