Initial evidence was first acquired in the late 1990s that PHA storage plays a physiological role in activated sludge cultures operated under dynamic feeding regimes. Since then, this subject has received much attention. Research has advanced considerably in the understanding of the mechanisms controlling microbial culture selection under an imposed selection pressure. We are now able to impose a function-driven control of microbial consortia that results in improved PHA production performance. Mixed cultures are seemingly able to attain similar PHA accumulation levels relative to known pure culture PHA producers.
However, many challenges remain – some relating the pure culture process and some specific to the mixed culture approach – which have so far hindered the demonstration at an industrial level of this promising approach for enhancing added value. Such challenges include but are not limited to:
The impact of microbial population dynamics on process performance (relatively well mastered) and process robustness;
The impact of the operating conditions for PHA accumulation on such structural properties of polymers as quality, molecular weight and monomer distribution: is there an intrinsic variability in mixed culture processes? Can this be controlled in the accumulation stage?
The extraction stage performance, sustainability, impact on product quality, and process cost;
PHA stabilization, formulation and processing;
Potential use of PHA in mixed bio-based polymer formulations;
(new) Application development;
Value chain development: who needs to be involved in first product development to secure feedstock, process and markets?
Market constraints and opportunities;
Overall process sustainability.
These issues and questions are in the forefront of the minds of everyone currently pursuing this path to the profitable use of waste-based feedstock through the production of a bio-based and biodegradable polymer that can be used to replace the non-biodegradable polymers responsible for mayor environmental problems.
By reflecting on these matters, by introducing new ideas and keeping abreast of different perspectives and progress in the field, we can jointly foster the creative dynamic and help build the critical mass necessary to achieving the next step… the next push forward that will enable this promising R&D to become an industrial reality.
Over the past decade, we scientists and businesses working on this process have established contact through a solid network of expertise which has given rise to a steady and productive dialogue and ongoing scientific discussions. Every two years, this dedicated scientific community comes together to participate in a workshop on MMC PHA production. First held in 2005 in Delft, The Netherlands, the workshop took place subsequently in Lund, Lisbon and Rome. Now it is with great pleasure that we would like to invite you all to the next stop for the MMC PHA workshop: Toulouse, France!
This new edition of the workshop held on September 11th and 12th 2014 will be organized by the LISBP (INSA, INRA, CNRS) with the support of Veolia. A call for abstracts and more information on the program and venue will be sent at a later date. This first announcement is meant as a reminder so that you can note the date in your diaries.