The massive use of plastics derived from the petrochemical industry and their resistance to biodegradation have produced mainly two problems from the point of view of Environmental Biotechnology: a) the contamination through the accumulation of those plastic residues in different terrestrial and aquatic environments, and b) an increase in the emission of CO2 to the atmosphere, and thus, of the greenhouse effect. This has made it mandatory to explore new alternative materials like the bioplastics, with mechanical properties equivalent to the conventional plastics, but less contaminating, and whose production is compatible with a sustainable development.
Among the bioplastics that are currently considered as possible alternatives, the most promising and worth highlighting are the polymers produced by certain bacterias that accumulate them in the interior of the cells in the shape of carbon reserve granules for when the growing conditions of the culture are not optimal. Once extracted they can be modified chemically, and produce a great variety of semi-synthetic polymers that are synthesized through the use of renewable sources (vegetable oils, natural sugars, etc.). Apart of its mechanical properties, that allows us to use them for the same things as the conventional plastics, bioplastics of natural origin have two other very relevant properties. On one hand, they are biodegradable, this is, they are degraded through natural recycling processes and are eliminated of the environment through the attack of bacteria and fungi that are part of the soils' flora. And on the other hand, they are biocompatible, so they can be introduced in the human body without any adverse reactions (allergies, rejections, etc.). This second property makes them ideal for the fabrication of surgical material, artificial tissues, drugs of sustained-release, etc.