A new method for growing bioplastics – polymers derived from renewable biomass and not fossil fuels like petroleum – promises to be more environmentally friendly than conventional bioplastic production. Interdisciplinary research at Tel Aviv University developed the process, which uses microorganisms that feed on seaweed, is biodegradable, produces zero toxic waste and recycles into organic waste.

Multiple recent reports highlight the alarming and distressing dispersion of discarded plastics, including the Image credit: Sea lettuce and anenome by Anna Barnett / CC BY 2.0deepest place on earth, the Marianas Trench, and inside marine life. Reducing this plague of plastic waste is the focus of multiple projects, from banning the use of plastic bags, cutlery and straws to creating biodegradable materials. Bioplastics tick two critical boxes on the list of desirable material characteristics: they are produced from renewable resources and they degrade faster than traditional plastics.

However, growing the biomass needed to produce bioplastics requires fertile soil and fresh water, two resources that in many parts of the world are in short supply. The demand to grow biomass to convert to plastic can conflict with the demand to produce food using those same resources, a disadvantage similar to growing crops for ethanol and biodiesel production. In addition, a 2010 University of Pittsburgh study determined that bioplastic production created more pollutants than fossil-fuel-based plastics due to the fertilizers needed to grow crops and the chemical processing required to convert organic material into plastic.

The Israeli research avoids use of both soil and fresh water, instead creating polyhydroxyalkanoate (PHA) from marine microorganisms that feed on multicellular seaweed. Using seawater, which is readily available in many countries, Haloferax mediterranei archaean organisms and Ulva sp. sea lettuce eliminates competition for land-based resources. This new process also eliminates toxic waste byproducts. PHA does not harm human tissue and is suitable for medical uses like sutures and single-use food packaging.

The research team, led by Dr. Alexander Goldberg of TAU’s Porter School of Environmental and Earth Sciences and Prof. Michael Gozin of the School of Chemistry, is currently researching the best bacteria and algae to use to produce bioplastics with different characteristics. Their research appears in the journal Bioresource Technonlogy in January 2019.