October 5 (WNN) — According to the authors of a study published by iScience on Tuesday, the alleged healing properties of spider silk may have no basis in science.
Earlier studies suggest that spider silk extracts, when applied to surgical sutures on the skin, for example, may help protect against infection if compromised.
In their analysis of silk from seven different spider species, the researchers said there was no evidence of antimicrobial activity, or the ability to stop bacteria or fungi from causing infections.
While this does not rule out that some spider silk from species not included in the study may have medicinal properties, it casts doubt on previous reports, he said.
Co-author Trine Bilde said in a press release, “We were unable to detect the antimicrobial activity of social spider silk regardless of method or microbe, and this made us curious about why other studies were able to “
“Then we began to closely examine papers reporting antimicrobial activity and became aware of the shortcomings of the methodology,” said Bilde, a professor of biology at Aarhus University in Denmark.
According to researchers at Utah State University, since the age of the Roman Empire, spider silk has been used to treat everything from skin wounds to warts.
Historically, doctors covered open wounds in cobwebs or advised patients to put cocoons on infected teeth, and synthetic forms of the material may also have technical applications.
Bilde and his colleagues said the spiders use their silk to protect their eggs, which provide the microbes with a high nutritional content.
However, rather than ward off microbial threats with intrinsic antimicrobial activity, the silken sheath around the eggs may simply act as a physical barrier, she said.
“Spider silk has always been admired and has an almost mythical status,” Bilde said.
However, “it is one of these myths that has been ‘founded’ by ‘belief’ and not by strong empirical support,” she said.
In addition to testing silk from seven spider species, Bilde and his colleagues reviewed data from 15 previous studies designed to assess the material’s antimicrobial activity.
Three of the included studies found no evidence of antimicrobial activity in spider silk, and that did not account for the risk of bacterial contamination of their samples, the researchers said.
They suggested that some studies may have inadvertently used the effects of solvents such as acetone or ethyl acetate to extract spider silk rather than spider silk.
“Instead of assuming that spider silk is antimicrobial, we should now assume that it is not,” Bilde said.
“We can still test the idea with new species and new organisms, but with a more cautious starting point,” she said.