Oxygen consumption and oxygen debt in the common whelk (Buccinum undatum) during aerial storage.

Main area:Marine biology
Target group:Biology
Educational level:Bachelor, Masters
Project description:

The common whelk (Buccinum undatum; in Danish: Almindelig konk) is subject to fishery in a number of European countries (especially England, with > 19,000 tons landed in 2014). The common whelk is regarded a delicacy in many countries and especially in the Far East. My group has since 2015 been engaged in a project (terminates in 2017) funded by the European Maritime and Fisheries Fund concerning establishment of a whelk fishery in Denmark. The background is to encourage small Danish coastal fishermen to start fishing whelks, which can supply the fishermen with a new and additional source of income. When whelks are landed they are typically stored in air (covered by wet clothes) at about 1 °C. If not further processed within 2 days the whelks will start to loose quality. What the loss of quality is caused by is however not know. A recent bachelor project in my group tested several possibilities, but the results were mostly inconclusive. No significant accumulation of lactic acid or succinate was found (both are markers for anaerobic metabolism). However, re-analysis of some of the samples using a different method (HPLC) showed presence of high lactic acid concentrations. Thus, the above lack of lactic acid might be an artefact. The protein content did not change during experiments (indicating no use of protein for energy metabolism). The energy store (i.e., glycogen) was shown to decrease and to be depleted within approximately 10 days. Whelks are known to have some ability to consume oxygen when aerial exposed. Therefore, it is possible that the whelks have been at least partial aerobic.
The aim of the project is to measure and compare the rate of oxygen consumption in aerial exposed and water submerged whelks at different temperatures. After exposures, whelks are transferred to oxygenated water and the oxygen debt (oxygen used for oxidation of anaerobic metabolites) is measured, which allows anaerobic metabolism during exposure to be estimated. Depending on the results and type of project the project can be expanded to include some biochemical measurements.

Methods used:Intermittent respirometry
Keywords:Common whelk, aerobic and anaerobic metabolism
Supervisor(s):  Bent Vismann