WHAT ARE THE DRIVERS OF FATTY ACID PRODUCTION? ANALYSIS OF PHYLOGENETIC SIGNALS AND OTHER KEY FACTORS

Candidate: Serena Sbrizzi
Supervisor: Dr. Lesley Campbell

ABSTRACT

Essential fatty acids such as Omega-3s and Omega-6s are key nutrients in supporting individual and ecosystem health. Currently, many essential fatty acids to humans are derived from fish and shellfish; however, growing human populations and declining fish and shellfish populations threaten access to these fatty acids and thus nutritional food security. I predicted that bioprospecting for essential fatty acids in plants can alleviate some harvesting pressure on aquatic ecosystems and provide new sources of plant-derived essential fatty acids. Understanding the distribution and patterns associated with fatty acid production in plants is the first step to achieving this. Using a meta-analytic approach allowed me to include a wide variety of taxa in the analysis. I used phylogenetic signal analysis to map fatty acid profiles including both presence and abundance of particular and important groups of essential fatty acids onto a plant phylogeny including algae, bryophytes, ferns and their allies, gymnosperms, and angiosperms. In addition, I explored how other factors including cultivation status, tissue, and climate were related to changes in fatty acid production to identify potential drivers of fatty acid production and provide guidance to bioprospecting endeavours. My phylogenetic signal analysis revealed that production of most essential fatty acids was randomly or ubiquitously distributed, while the concentration of most key fatty acids (including EPA, DHA, and nervonic acid) was significantly clustered in specific clades. Fatty acid content between crops and non-crops, as well as tissues of angiosperm, fern, and bryophyte clades differed significantly between some key fatty acids. Climate (via latitude and global climate deviations) also had some significant effects on groups of fatty acid (SFA, UFA, MUFA, and PUFA). In summary, I present new evidence for roles of phylogeny, climate, cultivation status, and tissue source in the production of key fatty acids in plants using a metaanalytic and phylogenetic signal analysis approach, exploring the evolutionary and environmental contexts that facilitate the production of fatty acids in plants.