skip to content

Yusuf Hamied Department of Chemistry

 

Photo courtesy Silvia Vignolini

How does red algae turn blue?

This is what Dr Silvia Vignolini and her colleagues wanted to know.

Irish moss seaweed, or chondrus crispus, is fundamentally a red algae, but its tips glow iridescent blue when submerged in water.

Silvia, in the Department of Chemistry, along with researchers from the Natural History Museum and other institutions, discovered that this effect is produced not by pigment, but by transparent layers in the plant's tips.

The iridescence occurs when the seaweed is wet, because the water affects the structure of the plates so that they reflect ultraviolet light in certain wavelengths.  The researchers conjecture this iridescence may help protect the algae from UV light, like a natural sunscreen. 

The research was published in Scientific Reports on 3 July.