Hydrothermal liquefaction (HTL) of cuticular materials from Agave americana and Capsicum annuum was performed for extended periods of time (72 h) at 360 degrees C meant to simulate long-term maturation of the organic matter. Both cuticular materials displayed evidence for possible oil production from the amounts of polymethylenic carbons in C-13 solid-state nuclear magnetic resonance spectra. The bio-oil yields were approximately 35 wt.% and exhibited heating values of 40.5 MJ kg(-1), comparable to those of typical crude petroleum. Analysis by two dimensional gas chromatography indicated that the A. americana bio-oil was dominated by a homologous series of n-alkanes, whereas cyclic and aromatic compounds were the major compounds identified in the C. annumm bio-oil. Further analysis using electrospray ionization-Fourier transform ion cyclotron resonance-mass spectrometry revealed the bio-oil samples were predominantly lipid-like in character. The result of this study demonstrate that one can utilize highly aliphatic biopolymeric components of certain plant materials to produce bio-oils that have the potential to be utilized as alternative fuels. (C) 2015 Elsevier Ltd. All rights reserved.