CORVALLIS, Ore. – Oregon State University researchers have developed a new method for producing stable pigments from fungi, a process they say can be scaled up to match the needs of manufacturers of paints, wood finishes and textile dyes.
Scientists have known for some time that fungi make pigments with blue-green, reddish-orange, yellow and brown hues, and since the Middle Ages, artists have used woods colored by fungal pigments, a process known as spalting.
But while the microorganisms can be grown in solution, capturing the pigments has required the use of toxic solvents, said Sara Robinson, an assistant professor in the OSU College of Forestry. Robinson has now found a way to use oils to harvest the pigments, and OSU has applied for a provisional patent on the technique.
Fungal pigments are stable and sticky, qualities that make them commercially useful.
“Their role in nature is to persist, to preserve the resource for the fungus,” said Robinson, who conducts research on fungi and their impacts on wood.
In a past research study in the Journal of Coatings, she compared the effects of spalting on 16 Pacific Northwest woods by inoculating them with three different fungi. In a study in the journal Coloration Technology, she reported the results of testing three fungal pigments on fabrics such as bleached cotton, spun polyester and worsted wool.
“All three pigments utilized in this study show signiﬁcant potential for use as textile dyes," she and her co-authors wrote.
The pigments extracted from spalting fungi can be carried in oil and water-based wood finishes and wood stabilizers. Wood workers would go nuts about having a finish that is spalted,” Robinson said.
Information about licensing the use of the pigment production process is available from Denis Sather in the Oregon State Office for Commercialization and Corporate Development.