| Autor: |
Adler LS; Department of Biology, University of Massachusetts at Amherst, MA, Amherst, 01003, USA. lsadler@ent.umass.edu., Fowler AE; Department of Biology, University of Massachusetts at Amherst, MA, Amherst, 01003, USA., Malfi RL; Department of Biology, University of Massachusetts at Amherst, MA, Amherst, 01003, USA., Anderson PR; Department of Biology, University of Massachusetts at Amherst, MA, Amherst, 01003, USA., Coppinger LM; Department of Biology, University of Massachusetts at Amherst, MA, Amherst, 01003, USA., Deneen PM; Department of Biology, University of Massachusetts at Amherst, MA, Amherst, 01003, USA.; Department of Biological Sciences, Binghamton University, NY, Binghamton, 13902, USA., Lopez S; Department of Biology, University of Massachusetts at Amherst, MA, Amherst, 01003, USA., Irwin RE; Department of Applied Ecology, North Carolina State University, NC, Raleigh, 27695, USA., Farrell IW; Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AE, UK., Stevenson PC; Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AE, UK.; Natural Resources Institute, University of Greenwich, Central Avenue, Chatham Maritime, Kent, ME4 4TB, UK. |
| Abstrakt: |
Many pollinator species are declining due to a variety of interacting stressors including pathogens, sparking interest in understanding factors that could mitigate these outcomes. Diet can affect host-pathogen interactions by changing nutritional reserves or providing bioactive secondary chemicals. Recent work found that sunflower pollen (Helianthus annuus) dramatically reduced cell counts of the gut pathogen Crithidia bombi in bumble bee workers (Bombus impatiens), but the mechanism underlying this effect is unknown. Here we analyzed methanolic extracts of sunflower pollen by LC-MS and identified triscoumaroyl spermidines as the major secondary metabolite components, along with a flavonoid quercetin-3-O-hexoside and a quercetin-3-O-(6-O-malonyl)-hexoside. We then tested the effect of triscoumaroyl spermidine and rutin (as a proxy for quercetin glycosides) on Crithidia infection in B. impatiens, compared to buckwheat pollen (Fagopyrum esculentum) as a negative control and sunflower pollen as a positive control. In addition, we tested the effect of nine fatty acids from sunflower pollen individually and in combination using similar methods. Although sunflower pollen consistently reduced Crithidia relative to control pollen, none of the compounds we tested had significant effects. In addition, diet treatments did not affect mortality, or sucrose or pollen consumption. Thus, the mechanisms underlying the medicinal effect of sunflower are still unknown; future work could use bioactivity-guided fractionation to more efficiently target compounds of interest, and explore non-chemical mechanisms. Ultimately, identifying the mechanism underlying the effect of sunflower pollen on pathogens will open up new avenues for managing bee health. |
Full text from SpringerLink