(Photo: Michael Podger / Unsplash)Spider silk has long been said to have an antibacterial effect. The ancient Greeks and Romans allegedly used the silk to treat flesh wounds, and some recent studies report antimicrobial activity (AMA) on spider silk, leading many cultures and social circles today to believe that the sticky substance is a worthwhile substitute for advanced antibacterial drugs . However, researchers at Aarhus University in Denmark have found the opposite; Spider silk does not appear to have any antibacterial properties, even when silk is studied by several species of spiders.
In your to learn Researchers Simon Fruergaard, Marie Braad Lund, Andreas Schramm, Thomas Vosegaard and Trine Bilde, published on Tuesday, report that they looked for AMA in seven types of spider silk, which explains differences within spider phylogeny. They tested for antimicrobial effects against Escherichia coli (better known as E. coli), Pseudomonas putida (sometimes related to skin infections) and Bacillus subtilis (a benign form of bacteria that does not harm humans or animals). Using direct contact assays (which test untreated silk for antibiotic sensitivity) and disc diffusion assays (which test silk extracts against the same), the team concluded that all three types of bacteria were not threatened by the silk.
“We couldn’t detect the antimicrobial activity of social spider silk, and that made us curious why other studies have shown antimicrobial activity in spider silk. We then began to scrutinize the papers describing the antimicrobial activity in minute detail and became aware of methodological flaws, ”said Tilde. called to Gizmodo about the research. A more realistic application of “spider silk” to wounds would include a spider-inspired rayon developed in the UK a few years ago. The synthetic material could one day be used to administer drugs and close wounds with less risk of infection.
However, spider silk is still incredibly tough. “Spider silk is known for its exceptional physical properties such as high tensile strength and flexibility,” says the study. “Silk is used as an anchor for a quick escape, as a noose to catch prey, to immobilize cannibalistic companions, to make egg boxes for protection. . . and even in silk diving bells, which make life easier underwater. ”Due to the wide range of possible uses and the general durability of silk, it initially seemed obvious to the researchers that it could also protect itself by killing bacteria. Unfortunately, that’s just not the case.