title: Characterization and biosynthesis of non-degradable polymers in plant cuticles.
abstract: The structure and monomeric composition of the highly aliphatic and non-saponifiable fraction of cutans isolated from the leaf cuticles of Agave americana L. and Clivia miniata Reg. have been elucidated. Spectroscopic Fourier transform infrared and 13C-nuclear magnetic resonance, calorimetric and X-ray diffraction studies, together with biopolymer analysis after exhaustive ozonolysis, showed that the cutan fraction consists of an amorphous three-dimensional network linked by ether bonds containing double bonds and free carboxylic acid functions. Data obtained from fatty acid sorption indicated that the new biopolymer investigated here has a highly hydrophobic character constituting an additional barrier biopolymer in those cuticles where it is present. Labelled [14C]linoleic acid was preferentially incorporated into the non-ester part of C. miniata leaf disks in comparison with the cutin fraction of the cuticular membrane. This indicates that the cis-pentadiene system of polyunsaturated fatty acids is involved in the formation of intramolecular linkages, mainly ether bonds, of the aliphatic biopolymer.
authors.affiliation: Departamento de Bioquímica, Biología Molecular y Química Orgánica, Facultad de Ciencias, Universidad de Málaga, Spain.
authors.forename: J F
authors.initials: JF
authors.lastname: Villena
authors.forename: E
authors.initials: E
authors.lastname: Domínguez
authors.forename: D
authors.initials: D
authors.lastname: Stewart
authors.forename: A
authors.initials: A
authors.lastname: Heredia
mesh_terms: D001692:Biological Transport; D010944:Plants / Q000737:chemistry*; D010946:Plants, Medicinal / Q000737:chemistry*; D011108:Polymers / Q000032:analysis*; D012995:Solubility
chemical_list: D011108:Polymers