Algae embedded in silica coatings could be used for the continuous production of a commercially important dye, say German scientists.  

Horst Böttcher and colleagues at research organisation, the society for the promotion of medical, biological and environmental technologies (GMBU), Dresden, made a biological ceramic material by immobilising living cells of the microalgae Haematococcus pluvialis in silica films.  

These algae naturally produce the dye astaxanthine, which is used in the food and cosmetic industries, and are used to produce the dye commercially. However in current methods, the extraction of the dye destroys the algae, meaning that a new time-consuming cultivation of the algae is needed for dye production to continue.  

Böttcher's team extracted the dye from their material using organic solvents, which only caused moderate damage to the algae. This means the continuous production of astaxanthine should be possible, said Böttcher.

'The combination of ceramic-like materials and biological components, called biocers is one of the most promising future technologies,' said Böttcher.  

Thibaud Coradin, a specialist in this field from Pierre and Marie Curie University, Paris, France, welcomed the work. 'As the diversity of living organisms that can be encapsulated in silica gels is expanding, the long-foreseen potential of biocers is turning into reality. This is a significant step forward the development of "in silica" biotechnological devices,' he said

'The improvement of the durability of the immobilized microorganisms and investigations of secondary metabolite profile are important areas of further research,' said Böttcher.

Rebecca Gillan