Proteins instead of plastic

New plastic-free materials for a better and more liveable future

Degrading plastic with microbial enzymes

An article by Dr Lin Römer, CEO of AMSilk GmbH

Products made of proteins will soon be available for many areas of daily life. Scientists and engineers are working hard to develop and produce protein-based materials that can satisfy our high demands for quality and performance while at the same time posing no burden to the environment because they are made of renewable resources and are fully biodegradable at the end of their lifetime.

Plastic products are everywhere

Numerous products that we wear on our bodies or use in our homes are manufactured from petroleum. A fossil fuel, petroleum is the main basic material used in the chemicals industry and huge quantities of it are incorporated into all kinds of different plastic products. A particularly good example is the textiles market: besides natural products like wool or cotton, fabrics for functional outdoor and sports clothing are mostly made of polyester, nylon or other synthetic fibres. Such materials frequently offer good mechanical properties and are durable and easy to process; above all, however, they are cheap and can be produced in large quantities.

The key disadvantage of these materials as far as our environment is concerned is that the overwhelming majority of them are neither produced from renewable resources nor biologically degradable. As a result, sooner or later all of these products end up on landfill sites or are incinerated. Particularly alarming is the fact that large quantities of plastic also find their way into the oceans, where they are broken down into microplastics and enter our food chains via marine animals.

What are the alternatives?

We wouldn't have this problem if many people – and ideally everyone – were willing to do without plastic products. But this is hardly a viable proposal. People want and buy good products. And nearly all high-performance products such as sports shoes or outdoor clothing can so far only be made using petroleum-based materials. Switching to natural products such as cotton, wool, hemp or traditional silk is not a realistic option. Not only do such products fail to achieve the required degree of performance; they also offer very poor scalability because traditional production methods have already more or less reached the limits of their capacities.

Microorganism-based production

We, and above all our environment, therefore need new materials that can meet a variety of criteria: it is just as important for such products to be of high quality and offer good performance as it is for them to be manufactured from renewable resources. The necessary industrial scalability, and the guarantee that the products can be disposed of in an eco-friendly manner or can be recycled, are no less crucial. This is where microbial production methods come into play. Bacteria and fungi are already being used to manufacture many of the products we use on a daily basis, such as vitamins and detergents. What is relatively new is the fact that such methods are also suitable for producing fibres and other materials.

Products made of proteins

Why do we rely to such an extent on fossil fuels when nature is demonstrating to us all the time how to do it better? Our skin, and the silk thread produced by a spider, consist of natural protein molecules. Proteins are the standard evolutionary material that is used even for the most complex tasks. It has recently become possible to use our knowledge of these materials for technical purposes.

One promising example of a future-proof material is made of silk proteins – though not produced by spiders, but in bioreactors with the aid of bacteria. The first products featuring these silk fibres are already available to buy, and others are about to be placed on the market. They are manufactured on the basis of renewable raw materials in a process that offers very good industrial scalability. In terms of their mechanical properties, these products are comparable to synthetic products, though they are much more skin-friendly and – unlike virtually all plastic materials – are fully biodegradable, which makes them so environmentally compatible.

Production of very large industrial quantities is currently being set up. Soon, in other words, we will find many products in our day-to-day lives that use microbe-based materials and can enjoy them without destroying the natural resources upon which we and our environment depend. Nature can teach us how to do things better – we just have to follow her example.