Back to nature, microbial production of pigments and colorants for food use.

Pigments-producing microorganisms are quite common in Nature. However, there is a long journey from the Petri dish to the market place. Twenty-five years ago, scientists wondered if such productions would remain a scientific oddity or become an industrial reality. The answer is not straightforward as processes using fungi, bacteria or yeasts can now indeed provide carotenoids or phycocyanin at an industrial level. Another production factor to consider is peculiar as Monascus red colored food is consumed by more than one billion Asian people; however, still banned in many other countries. European and American consumers will follow as soon as "100%-guaranteed" toxin-free strains (molecular engineered strains, citrinin gene deleted strains) will be developed and commercialized at a world level. For other pigmented biomolecules, some laboratories and companies invested and continue to invest a lot of money as any combination of new source and/or new pigment requires a lot of experimental work, process optimization, toxicological studies, and regulatory approval. Time will tell whether investments in pigments such as azaphilones or anthraquinones were justified. Future trends involve combinatorial engineering, gene knock-out, and the production of niche pigments not found in plants such as C50 carotenoids or aryl carotenoids.