The Identification and Quantification of Leaf Mesophyll Oil Bodies During the Development of Native or Adapted Plant Species

Abstract

Oil bodies have recently been identified in mesophyll cells of several species of angiosperms. These oil bodies are predicted to store triacylglycerides similar to storage oil bodies found in seeds of several plant species. Seed triacylglyceride oil is a common feedstock used for production of biofuels. This study examines the production and composition of these oil bodies in four plant species to determine if leaf oil could be used as a new feedstock for biofuel production. The species studied were species predicted to grow well in different climatic regions of Texas, including regions of marginal land with environmental stress: Agastache foeniculum (Pursch) Kuntze (Anise Hyssop), Asclepias incarnata L. (Swamp milkweed), Cynara cardunculus L. (Cardoon), and Helianthus maximiliani Schrad. (Maximilian sunflower). Leaf oil body production was monitored throughout the entire plant over four months of development for each species. Also, extractable oil per leaf dry weight was monitored over development. Extracted oil from each species was separated using thin-layer chromatography (TLC) to determine the lipid composition of leaves from each species and to determine oil body composition. The main results of this research showed that in each plant species oil bodies accumulated in the leaves as the leaves senesced. Also, the amount of extractable lipids from each species varied over time. However, there were few correlations between the presence of oil bodies in leaves and the total amount of extractable lipids from leaves, suggesting that oil bodies are poor predictors of extractable lipids in leaves.