A research project led by UK company Biome Bioplastics has shown organic chemicals can be extracted from the plant material lignin.
This could lead to a product that meets the need for a cheaper and better bioplastic, the company says.
Lignin is a hydrocarbon that provides structural support in trees. As a waste product of the pulp and paper industry it is abundant and cheap, making it an ideal base for bioplastics.
Scientists have been trying to extract chemicals from lignin for more than 30 years. Last year Biome Bioplastics was awarded a grant from the Technology Strategy Board to investigate lignin as a new source of organic chemicals for bioplastics manufacture.
The project, in conjunction with the University of Warwick’s Centre for Biotechnology and Biorefining, has shown bacteria found in soil can break down lignin. On a laboratory scale, it has produced organic chemicals in ‘promising yields.’
Paul Mines, CEO, Biome Bioplastics, told FoodProductionDaily.com the next step will look at how yields of the chemical can be increased. The first commercial target is to use these chemicals to replace oil-derived equivalents in plastic.
“It’s about trying to get plastics derived from a cheap source, and a source not competing with food,” he said.
“We’ve got a particular microbe – Tim Bugg [director of the biotechnology and bio-refining centre] had done a lot of background work, but in the last years we’ve applied his work to get the chemicals we want out of lignin.
“It has worked very well, we did it first at test tube and flask level, and then with quantities of several litres.”
Tackling a high price point
Challenges facing the bioplastics market include the need for improved performance in the chemicals used, and the cost of the product – which is currently two to four times more expensive than conventional plastics, according to Biome.
But Mines believes a high performance polymer, made economically from renewable sources, could ‘considerably increase’ the bioplastic market.
“What we will see is bioplastics grow in the next few years, in a limited way - we are limited to sectors or brands where the end customer is prepared to pay a premium for knowing packaging has a heavily biodegradable component.
“To open up the mass market, we have to open up the price point. Lignin is capable of doing that, although I can’t guarantee it will.”
All of Biome’s existing ranges are food contact approved, and a new lignin material would be developed in this way as well.
“One of our challenges for bioplastics [for food] is people are buying the tomatoes, not the packaging,” Mines said. “Although there are things you can do to brand the product around packaging, it’s different to the plastic in an iphone or a car where it’s a fundamental product.
“This makes pricing [of bioplastics] particularly challenging in the food aspect.”
Strength from nature
Lignin is second only to cellulose as the most abundant organic material on Earth. It is a waste product of the pulp and paper industry.
“It’s such a shame – nature’s gone to all this effort to hold up the tree, yet it’s the bit that’s not been used so far,” said Mines. “We don’t use this strong part – this is about using nature as a factory to build up a structure.”
Biome Bioplastics is a UK developer of natural plastics. Its offers a range of biodegradable and compostable plastics made from renewable resources, and the company has a research and development programme focused on improving performance and reducing costs.