Novel Process for Making Bioplastic Polymers from Microorganisms that Feed on Seaweed

A method for making bioplastic polymers that avoid the need for using fresh water or land—resources that are scanty in many regions across the globe—has been described in a new study performed at Tel Aviv University.

The polymer is extracted from microorganisms that feed on seaweed. It recycles into organic waste, is biodegradable, and does not produce any zero toxic waste.

The innovation was the outcome of a multidisciplinary association between Dr Alexander Golberg of TAU’s Porter School of the Environmental and Earth Sciences and Prof. Michael Gozin of TAU’s School of Chemistry. Their study was recently reported in the Bioresource Technology journal.

United Nations has reported that plastic accounts for up to 90% of all the pollutants in the oceans; however, there are very few environment-friendly, comparable alternatives to the material.

Plastics take hundreds of years to decay. So bottles, packaging and bags create plastic ‘continents’ in the oceans, endanger animals and pollute the environment. Plastic is also produced from petroleum products, which has an industrial process that releases chemical contaminants as a byproduct. A partial solution to the plastic epidemic is bioplastics, which don’t use petroleum and degrade quickly. But bioplastics also have an environmental price: To grow the plants or the bacteria to make the plastic requires fertile soil and fresh water, which many countries, including Israel, don’t have. Our new process produces ‘plastic’ from marine microorganisms that completely recycle into organic waste.

Dr Alexander Golberg, Porter School of the Environmental and Earth Sciences, Tel Aviv University.

Microorganisms that feed on seaweed were used by the scientists to synthesize a bioplastic polymer known as polyhydroxyalkanoate (PHA). “Our raw material was multicellular seaweed, cultivated in the sea,” stated Dr Golberg. “These algae were eaten by single-celled microorganisms, which also grow in very salty water and produce a polymer that can be used to make bioplastic.”

There are already factories that produce this type of bioplastic in commercial quantities, but they use plants that require agricultural land and fresh water. The process we propose will enable countries with a shortage of fresh water, such as Israel, China and India, to switch from petroleum-derived plastics to biodegradable plastics.

Dr Alexander Golberg, Porter School of the Environmental and Earth Sciences, Tel Aviv University.

Dr Golberg told that the innovative study could completely transform the worldwide efforts to clean the oceans, without any influence on arable land and without the use of fresh water. “Plastic from fossil sources is one of the most polluting factors in the oceans,” he stated. “We have proved it is possible to produce bioplastic completely based on marine resources in a process that is friendly both to the environment and to its residents.”

“We are now conducting basic research to find the best bacteria and algae that would be most suitable for producing polymers for bioplastics with different properties,” he concluded.

The study was partially funded by the TAU-Triangle Regional R&D Center in Kfar Kara under the academic auspices of Tel Aviv University, and by the Israeli Ministry of Energy and Infrastructures.