Development of biopolyesters (PHA) as part of the Swiss priority program in biotechnology

The Swiss Priority Program in Biotechnology of the Swiss National Science Foundation that lasted between 1992 and 2001 had a boosting effect on many biotech disciplines and on the developments of polyhydroxyalkanoates (PHAs) in Switzerland in particular. The funding organization led by Prof. Oreste Ghisalba enabled a better understanding of the PHA biosynthesis and the development, as well as the implementation of novel bioprocesses (e.g. two-phase fermentations, multiple nutrient limited growth conditions, multi-stage chemostats, and product formation in different host organisms). However, production of PHA in Switzerland appeared to be impossible for cost reasons due to the strong competition from cheaper, petrol-based plastics. The recent reports on environmental issues with non-degradable plastics has triggered a general change in the perception of biodegradable plastics, giving them an added value and thus justifying a higher price. Ongoing research focuses on the sustainable production of PHAs using carbon waste streams, synthesis gas or even CO2