Anthocyanins, multi-functional natural products of industrial relevance: Recent biotechnological advances.

Anthocyanins, the color compounds of plants, are known for their wide applications in food, nutraceuticals and cosmetic industry. The biosynthetic pathway of anthocyanins is well established with the identification of potential key regulatory genes, which makes it possible to modulate its production by biotechnological means. Various biotechnological systems, including use of in vitro plant cell or tissue cultures as well as microorganisms have been used for the production of anthocyanins under controlled conditions, however, a wide range of factors affects their production. In addition, metabolic engineering technologies have also used the heterologous production of anthocyanins in recombinant plants and microorganisms. However, these approaches have mostly been tested at the lab- and pilot-scales, while very few up-scaling studies have been undertaken. Various challenges and ways of investigation are proposed here to improve anthocyanin production by using the in vitro plant cell or tissue culture and metabolic engineering of plants and microbial culture systems. All these methods are capable of modulating the production of anthocyanins , which can be further utilized for pharmaceutical, cosmetics and food applications. • Chemistry and biosynthetic pathways of anthocyanins. • Regulation of anthocyanin biosynthetic pathways by transcription factors and phytohormones. • Non-engineered plant cell and tissue cultures as useful systems for anthocyanin production. • Engineering of anthocyanin production in plants targeting transcription factors. • Engineering of anthocyanin production by microbial cells including prokaryotic and eukaryotic microorganisms. [ABSTRACT FROM AUTHOR]