organisms. Some microorganisms and enzymes capable of degrading such
polymers have been identified [7, 10].
Different classifications of various biodegradable polymers have been proposed.
We propose to classify the biodegradable polymers according to their synthesis
process (Fig. 2.1): (i) polymers from biomass such as agro-polymers from
agro-resources (e.g., starch or cellulose), (ii) polymers obtained by microbial
production such as the polyhydroxyalkanoates (PHAs), (iii) polymers conventionally
and chemically synthesized from monomers obtained from agro-resources,
e.g., the polylactic acid (PLA), and (iv) polymers obtained from fossil resources.
Only the first three categories (i–iii) are obtained from renewable resources.
We can further classify these biodegradable polymers into two main categories:
the agro-polymers (category i) and the biodegradable polyesters or biopolyesters
(categories ii–iv).