Indoles and the advances in their biotechnological production for industrial applications

Abstract

Indole is a signalling molecule produced both by bacteria and plants. In this review its signalling role between microbes and in particular in the human gut is discussed. Besides the natural roles, indole also has value for flavour and fragrance applications, for example, in food industry or perfumery. Additionally, indole can be derivatized to several halogenated and oxygenated compounds that can be used as natural colourants or have promising bioactivity with therapeutic potential to treat human diseases. Indole is traditionally obtained from coal tar. Biocatalytic approaches have been developed to convert indole into halogenated and oxygenated derivatives. This review will discuss recent advances in production of indole from glucose or tryptophan by fermentation and the production of derived halogenated and oxygenated derivatives by microbial cell factories.

Keywords

Indole / Indigoids / Biological role / Bioactives / Microbial cell factories

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Funding

NWO(053.80.732); CoBioTech ERA(722361); Renewable Resources Scheme FNR(22023517); Universit?t Bielefeld (3146)