The effects of water temperature on fatty acid content in the diatom, navicula pelliculosa

Algae are critical to aquatic ecosystems and provide nutritious food to primary consumers due to their ability to synthesize essential fatty acids, in particular, long-chain polyunsaturated fatty acids (LC-PUFA). Aquatic ecosystems are experiencing increases in surface water temperatures as a result of anthropogenic climate change. Elevated water temperatures can potentially cause thermal stress for algae and disrupt critical physiological and biochemical mechanisms. As a response to temperature changes, fatty acid composition in membranes shifts in order to maintain membrane fluidity. To gain a better understanding of how elevated temperature influences fatty acid composition, growth experiments of a cosmopolitan freshwater diatom species, Navicula pelliculosa, were performed in a temperature-controlled laboratory environment. Diatom cultures were grown under different thermal regimes to examine the effects of temperature and time on LC-PUFA content. Temperature treatments were found to elicit an asymmetrical response in FA content, potentially resulting in reduced LC-PUFA availability.