Everyone knows plastic is bad for the environment. That’s why bioplastics – plastics made from renewable sources like plants or old waste – were invented. But these bioplastics can’t be created everywhere since the plants they use require fresh water, a scarce resource in many countries.
One such country is Israel, which does not have a surplus of fresh water. Other countries suffering from the same problem are China and India, whose size and resulting plastic consumption is very bad news for the planet.
This is the problem researchers from Tel Aviv University wished to resolve by developing bioplastic polymers derived from microorganisms that feed on seaweed. These can be bred in salty seawater without impinging on scarce freshwater resources.
The result is a biodegradable polymer that produces zero toxic waste and recycles into organic waste. The study that led to it, carried out by Alexander Golberg and Prof. Michael Gozin from Tel Aviv University, was recently published in the journal Bioresource Technology.
“Plastics take hundreds of years to decay. So bottles, packaging and bags create plastic ‘continents’ in the oceans, endanger animals and pollute the environment,” said Golberg, a senior lecturer at TAU’s Porter School of the Environment and Earth Sciences.
“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,” he added.
“Our new process produces ‘plastic’ from marine microorganisms that completely recycle into organic waste.”
To do so, the researchers harnessed microorganisms that feed on seaweed to produce a bioplastic polymer called polyhydroxyalkanoate (PHA).
“Our raw material was multicellular seaweed, cultivated in the sea,” Golberg said. “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,” he explained.”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.”
According to Golberg, the study could revolutionize the world’s efforts to clean the oceans without affecting arable land and without using fresh water.
“Plastic from fossil sources is one of the most polluting factors in the oceans,” he said. “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,” Golberg concluded.
[Photo: Michael Coghlan / Flickr ]