A study carried out at Finland's VTT Technical Research Centre has found that wild berries – raspberries, sea buckthorn, bilberries, strawberries, cloudberries and lingonberries – contain antibacterial compounds that destroy harmful bacteria. According to the data obtained by VTT, raspberries are the most suitable for further processing, because once the juice has been extracted, plenty of both skins and seeds remain. A small quantity of berry extract is particularly effective against the dangerous MRSA bacteria found in hospitals. It could also make it possible to reduce the use of antibiotics without weakening their effect. Raspberry extract can be used as a raw material in the food and cosmetics industries, and also for medical purposes, for example in sprays, creams, transdermal patches and wound dressings.
"This product (the extract) could quite simply be used in hospitals, for instance by spraying it onto the patient's skin before surgery," VTT senior scientist Panu Lahtinen (Panu Lahtinen) and associate professor and senior adviser Kirsi-Marja Oksman-Caldentey (Kirsi-Marja Oksman-Caldentey) wrote in a letter to the forest.fi portal.
While preventing dangerous microbes from multiplying on human skin, the berry extracts do no harm to the beneficial bacteria living there. According to Lahtinen, earlier studies confirm this observation. VTT has been researching wild berries for more than 20 years.
The wild raspberry (Rubus idaeus) is fairly widespread and well known across northern Europe. In Finland it is found as far as the Oulu region in the centre of the country, and in places even further north. Raspberries grow in grassy, moist forests, near ditches, streams and rivers, at forest edges, and also in clear-fell areas and along roadsides.
Antibacterial compounds protect against mould fungi
In the natural environment, the "job" of these antibacterial compounds is to protect the berry seeds from, for example, attack by mould fungi before germination. The same compounds prevent dangerous microbes from developing on human skin. The antibacterial compounds can be obtained without using harmful solvents; VTT has patented an environmentally friendly technology for this purpose. Panu Lahtinen says that the product developed from berries and nanocellulose is entirely biological.
"The fast-acting surgical spray and dressing are based on a production process we have developed, in which the nanocellulose film and its pores are impregnated with berry extract so as to avoid the antibacterial compounds being retained in the fibres," Lahtinen says.
Nanocellulose fibres, obtained by grinding down ordinary cellulose, are very, very small – a few nanometres in length (roughly one hundred-thousandth of the thickness of a sheet of paper). Because nanocellulose is a natural material, it is compatible with human cells and tissues, and no rejection has been observed. Similar compounds can be produced by cultivating plant cells, and it is worth noting that in that case fluctuations in berry harvests would not affect production.
"Further information is needed, particularly from toxicological tests of the kind previously carried out on cloudberry seed extract. Some tests could also be run within the current EU project InnCoCells. We estimate that bringing such a product to market will take at least 1.5–2.5 years, since our aim is approval for the extract to be used in medicine," write Lahtinen and Oksman-Caldentey.
The two researchers and their team are looking for a company that could collaborate with VTT, or join it, in order to take the project towards commercialisation.
It should be added that the research has established that antibacterial properties are found not only in forest berries but also in many tree species: a doctoral thesis written and defended at the University of Jyväskylä concluded that extracts obtained from pine, spruce, birch, oak, eucalyptus and alder, for instance, show natural antiviral activity on various surfaces.
The World Health Organization has included antibiotic-resistant bacteria on its list of the ten most significant international health problems.
MRSA bacteria, known as "hospital-acquired bacteria", are causing an increasing number of wound infections that are very difficult to treat.
In Finland, around a fifth of the population are carriers of MRSA bacteria without knowing it. If the bacterium enters a wound caused by skin damage or a medical operation, the consequences can be fatal.
https://forest.fi/article/tuttu-metsamarja-vadelma-vastaa-globaaliin-uhkaan/
https://www.vttresearch.com/en/news-and-ideas/berry-extracts-and-nanocellulose-bioactive-skin-sprays-and-surgical-dressings
https://jyx.jyu.fi/handle/123456789/93421