Image courtesy of WILDLIFE GmbH / Alamy
Joel Kontinen
Intelligent design has provided zebrafish eggs to produce
a chemical that keeps the suns rays from
harming people. The chemical is known as gadusol.
A team led
by Ping Zhang at Jiangnan University, China,
inserted genes from zebrafish into the bacterium Escherichia coli to
give it the enzymes needed to synthesise gadusol. Then, by using small RNA
molecules to dial up gadusol production in the bacteria and tweaking their
growing conditions, they increased the yield by nearly 93 times, from 45.2
milligrams per litre of liquid growth medium to 4.2 grams per litre.
In
experiments, gadusol displayed antioxidant properties comparable to vitamin C,
suggesting it may help neutralise free radicals that cause damage in cells.
Gadusol is
transparent, unlike melanin, and yet is perfectly tuned to block out harmful UV
rays from the sun, which makes it ideal for organisms hiding from prey. “I
think we haven’t necessarily given it the praise that it deserves,” says James Gagnon at the University of Utah, who was part
of a team that discovered gadusol’s role as a sunscreen in fish embryos. “This
is a great molecule.”
Gadusol is
found in the eggs of zebrafish, salmon and sturgeon, as well as coral, where
it protects organisms from ultraviolet
damage. But
it’s only found in small quantities so extracting it from organisms for use as
a sunscreen is impractical
Gagnon says
further testing is needed, but the compound is likely to be safe for humans and
the environment because so many animals already use it. Thanks to its
transparency, it might also avoid the milky residue that some current
sunscreens leave on the skin.
“Everyone
wants to hint that this is going to be a great sunscreen for humans,” says
Gagnon.
Source:
Matthew Sparkes 2026 Natural sunscreen found in fish eggs can be made by E. coli factories | New Scientist 13 May