Location: Honey Bee ResearchTitle: Antioxidants in wax cappings of honey bee brood Author
Submitted to: Journal of Apiculture Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/20/2010
Publication Date: 10/20/2010
Citation: Sammataro, D., Leblanc, B.W., Finley, J.V., Carroll, M.J., Torabi, M. 2010. Antioxidants in wax cappings of honey bee brood. Journal of Apiculture Research. 49(4):293-301. Interpretive Summary: Wax cappings from brood cells of immature honey bees (infested and non-infested with Varroa mites) were examined for antioxidant activity. These cappings are composed of beeswax, propolis, and silk from the cocoons. Using two techniques to determine antioxidant activity (DPPH and FRAP) we saw a significant difference in the percent activity between infested and non-infested workers. There was also a difference between queenlines, including Africanized, Hygienic, SMR, Italian and Russian lines. There was a significant difference in the drones and workers and of cappings from infested vs. non-infested brood. Infested drone cappings differed from infested workers. Antioxidant activity has never been assessed in brood cappings before and may be an indication of colony health and the queenlines resistance to Varroa. Future work will investigate this in more detail, including if antioxidants are a response to immune activity.
Technical Abstract: This is the first time that non-food items from honey bee colonies were assessed for antioxidant activity as it related to Varroa-infestation. Antioxidant activity may be an indication of bee health and while antioxidants are present in honey, propolis, pollen and royal jelly, little work has been done looking at the wax cappings that protect developing bee larvae. The wax cappings that cover honey bee brood is composed of beeswax and propolis, the latter is a resinous material collected from plants and has anti-microbial properties. The 2,2-diphenyl-l-picryl-hydrazyl (DPPH) was used to determine the antioxidant activity; the other assay was the ferric reduction capacity (FRAP). These two assays measure different aspects of total antioxidant activity, namely free radical scavenging or "quenching" activity of samples and therefore provides some estimate of the sample's ability to quench reactive oxygen species (ROS). The FRAP assay is used to measure ferric ion reduction activity (reduction from Fe3+ to Fe2+ ion) of samples and therfore provides a general indication of reduction capability in tissues. There was a significant difference in the percent scavenging activity (DPPH) between infested and non-infested workers (F=15.4, df=1, P=0.002), and between queenlines (F=16.1, df=4, P=0.001). Africanized were different from Hygienic, SMR and Italian workers, Hydienic was significantly different from Russian, SMR and Africanized, Russian was significantly different from all except Africanized, SMR was different from all (P less than 0.05) and California Italians different from all except Hygienic. There was a significant difference in the ferric ion reduction activity (FRAP assay) in the drones vs. workers and of cappings from infested vs. non-infested brood. Infested drone cappings differed from infested workers (F=9.4, df=1, P=0.004) for the [Qu] and the intercept F=340.8, df=1, P=0.000). There was also a difference between workers from the queenlines (F=6.4, df=4, P=0.004) and between infested vs. non-infested workers (F=8.1, df=1, P less than 0.001). Africanized differed from Hygienic (h) and Italians (wca); Hygienic differed from Russian and Africanized, Russian was different from all except Africanized; SMR was different from Russian and Italian was different from Africanized and Russian.