From plant polyester to wound dressing
Our skin is the body’s number one defence against the microbial pathogens that can lead to infection. That being said, while the skin is a remarkably strong barrier, it isn’t impenetrable. For example, whenever you suffer from a wound, whether it be something as harmless as a scratch or as critical as a laceration, it creates an opening in the skin that pathogens enter through. However, here the skin has a bit of a superpower that allows it to automatically repair itself, essentially closing off the wound. Unfortunately, people with a compromised immune system often suffer from chronic, non-healing wounds, making them particularly susceptible to infection. To better protect these patients, one EU researcher is turning to plants. “Over the course of millions of years, plants have developed a remarkable ability to protect themselves against everything from UV light to predators and disease,” says Cristina Silva Pereira, a biochemist at the Institute of Chemical and Biological Technology António Xavier. With the support of the EU-funded MIMESIS project, Silva Pereira is working to create a biomaterial-based wound dressing that draws its inspiration from plant polyesters and is thus able to mimic the skin’s antimicrobial and regeneration properties.
A natural twin of our skin
Polyesters are part of what covers and protects the aerial parts of plants – the stems, fruit, leaves, branches, basically all the above-ground parts. As Silva Pereira explains, there are two types of polyesters found in plants, cutin and suberin. “While both polyesters are ubiquitous in plants, each serves a unique purpose,” she adds. “Whereas cutin is a waxy, repellent substance used to protect the plant’s aerial tissues, suberin is found in periderms such as the bark of trees and tubers where it builds a barrier against an external threat.” So, what does all this have to do with human skin and wounds? “This unique combination of polyesters is almost a natural twin of our outer layer of skin,” notes Silva Pereira. “As such, it has the potential to form the basis of wound-dressing materials.”
Potentially life-saving solutions
To get from polyester to wound dressing, the MIMESIS project has developed an innovative, easy method for extracting the cutin and suberin from plants. Using a biocompatible ionic liquid as the main extractant, the process can recover a near native form of the polyesters and, most importantly, preserve its film-forming abilities. “Being able to preserve these native barrier properties, especially their antimicrobial, bactericidal and anti-biofouling capabilities, represents a major step towards the development of plant polyester-based wound materials,” says Silva Pereira. Silva Pereira is quick to add that achieving such groundbreaking results was only possible thanks to the support of the European Research Council. “This grant made what I previously could never have envisaged possible,” she concludes. “Bringing together a stellar network of collaborators, ranging from experts in polymers and materials science to plant biology, genetics and biorefinery, we were able to see how plant biology could be translated into potentially life-saving solutions.” That research team is now working to consolidate and publish its work. It is also looking at using its findings on plant immunity to create a proof of concept for producing safe, bio-derived ingredients with potential application in the field of functional materials and agro-additives.
MIMESIS, plant polyester, wound dressing, skin, microbial pathogens, infection, wound, immune system, plants, biomaterial