NMR biomarkers of cold stress resistance in honey bees

Saet Byeol Lee

Master's thesis

Abstract:

Honey bees fall into a comatose state in the ambient temperature ranges of 9 to 12C with cold death occuring at -2 to -6C. This study placed honey bees (Apis mellifera) into low temperature (7.6C), and observed honey bees falling into a comatose state. We found that approximately the half of the honey bees fell into a chill coma, and the others did not fall into a comatose state but remaining alert. To determine the metabolic differences between honey bee group which fell into a comatose state and the honey bee group which did not fall into a comatose state, the present study used 1H NMR spectroscopy to measure the metabolomic responses. This study detected 11 of significant metabolic features: AMP, acetate, carnitine, glutamine, methylguanidine, NAD+, o-phosphocholine, phenylalanine, putrescine, trehalose, and β-alanine. Trehalose, as well as amino acids were higher in both honey bees groups. However, all of the significant compounds in the non-coma honey bee group (except for phenylalaine) was 1.2 times to 2.4 times higher than in the honey bee group which fell into a comatose state. The highest compound was dissacharide, trehalose which is known as a blood sugar compound in insects, and is also an important cryoprotectant for insects. Amino acids, alanin and proline which are typical energy precursors of insects, were not detected in the present study. However, glutamine concentrations were significant in the non-coma honey bees group as well as carnitine which is crucial for fatty acid oxdiation.

Keywords

NMR analysis, Honey bee, Cold resistance, Chill coma

Language used: English

Date on which the thesis was submitted / produced: 11. 4. 2019

Thesis defence

• Supervisor: doc. Ing. Jaroslav Havlík, Ph.D.

Czech University of Life Sciences Prague

Faculty of Agrobiology, Food and Natural Resources

Master programme / field:
Sustainable Agriculture and Food Security / Sustainable Agriculture and Food Security