Red, red brine

Red, red brine

THIS SALT LAGOON, resembling a painting by Mark Rothko, is the biggest algae farm in the world.
Located by the coast in Western Australia, it contains the single-celled Dunaliella salna. These usually
appear green, but under the bright Australian sunlight they begin to produce beta carotene-a pigment
that gives pumpkins and carrots their orange colour. It's farmed for use in both food colourings
and medicines. "It is a photo-protectant", says Alison Smith, Professor of Plant Biochemistry at Cambridge University.This means the algae form the pigment in direct response to the incident light in order to protect
themselves against damage from the Suns harmful ultraviolet rays. The algae are grown up to high density in
one place and then flooded into the shallow open ponds explains Prof Smith. As the water evaporates the
salt concentration increases, and this exacerbates the response. The farm is made up of a network
of connecting lakes that fed are from the salty lndian Ocean, in order to encourage production of
beta-carotene.