**1. Introduction**

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Polymers are long chain macromolecules made up of many repeating units called monomers. They are found in nature and can also be made synthetically. Natural/bio polymers are considered to be environmental benign materials as opposed to synthetic polymers. Research geared toward producing innocuous products from biopolymers has intensified. Improved understanding of properties of biopolymers allows for the design of new eco-friendly materials that have enhanced physical properties and that make more efficient use of resources. Biopolymers also have the advantage of being biodegradable and biocompatible. They are therefore of interest for application in advanced biomedical materials, for instance tissue engineering, artificial bones or gene therapy (Eduardo et al., 2005). Other possible fields of applications are related to electrical properties, making this class of materials attractive for potential uses in electronic switches, gates, storage devices, biosensors and biological transistors (Finkenstadt & Willett 2004). Plant biopolymers constitute the largest pool of living organic matter most of which can be attributed to four distinct classes of organic compounds; lignin, cellulose, hemicellulose and cuticles. Cuticles are mainly made up of polymethylenic biopolymers which include cutin and suberin. Cutincontaining layers are found on the surfaces of all primary parts of aerial plants, such as stems, petioles, leaves, flower parts, fruits and some seed coats. In addition, cutin may be found on some internal parts of plants such as the juice-sacs of citrus fruits (Heredia, 2003). Composition, structure and biophysical data of plant cuticles have recently been reviewed (Jeffree, 2003; Pollard et al. 2008; and Dom ́nguez et al., 2011) and will only be mentioned briefly. The main constituents of cutin are esterified fatty acids hydroxylated and epoxy hydroxylated with chain lengths mostly of 16 and 18 carbon atoms. It also contains some fraction of phenolic and fluvanoid compounds.
