Research & Teaching Faculty

Very-long-chain 3-hydroxy fatty acids, 3-hydroxy fatty acid methyl esters and 2-alkanols from cuticular waxes of Aloe arborescens leaves

TitleVery-long-chain 3-hydroxy fatty acids, 3-hydroxy fatty acid methyl esters and 2-alkanols from cuticular waxes of Aloe arborescens leaves
Publication TypeJournal Article
Year of Publication2015
AuthorsRacovita, RC, Peng, C, Awakawa, T, Abe, I, Jetter, R
JournalPhytochemistry
Volume113
Pagination183 - 194
ISSN0031-9422
KeywordsWax ester isomers
Abstract

Abstract The present work aimed at a comprehensive chemical characterization of the cuticular wax mixtures covering leaves of the monocot species Aloe arborescens. The wax mixtures were found to contain typical aliphatic compound classes in characteristic chain length distributions, including alkanes (predominantly C31), primary alcohols (predominantly C28), aldehydes (predominantly C32), fatty acid methyl esters (predominantly C28) and fatty acids (bimodal distribution around \{C32\} and C28). Alkyl esters ranging from \{C42\} to \{C52\} were identified, and found to mainly contain \{C28\} alcohol linked to C16–C20 acids. Three other homologous series were identified as 3-hydroxy fatty acids (predominantly C28), their methyl esters (predominantly C28), and 2-alkanols (predominantly C31). Based on structural similarities and homolog distributions, the biosynthetic pathways leading to these novel wax constituents can be hypothesized. Further detailed analyses showed that the A. arborescens leaf was covered with 15 μg/cm2 wax on its adaxial side and 36 μg/cm2 on the abaxial side, with 3:2 and 1:1 ratios between epicuticular and intracuticular wax layers on each side, respectively. Terpenoids were found mainly in the intracuticular waxes, whereas very-long-chain alkanes and fatty acids accumulated to relatively high concentrations in the epicuticular wax, hence near the true surface of the leaf.

URLhttp://www.sciencedirect.com/science/article/pii/S0031942214003203
DOI10.1016/j.phytochem.2014.08.005