Microorganism-mediated production of anthocyanins: Current progress and future prospects

Anthocyanins are a type of water-soluble pigments widely distributed in colorful plants, which have been extensively used in food and cosmetics industry. The current production of anthocyanins heavily depends on extraction from plant materials, which leads to low purity and inconsistency among batches. Compared with conventional extraction, microorganism-mediated production of anthocyanins has advantages such as a short production cycle, high purity, low waste production, low energy requirements, and consistency between different batches. However, issues such as poor gene availability, instable engineered strains, and low yield limit the microorganism-mediated production of anthocyanins. Therefore, we would like to review the current progress regarding the generation of anthocyanins using microorganisms. Compared with previous studies focusing on this topic, the current review comprehensively summarizes different microbial systems capable of synthesizing anthocyanins, and provides information that can demonstrate the selection and engineering of microbial strains, and optimization of substrates, enzymes, and fermentation technologies. In addition, the review for the first time discusses the microorganisms that can naturally produce and secret anthocyanins. The review will motivate researchers interested in microorganism-mediated production of anthocyanins, and provide valuable information to facilitate the application of anthocyanins generated by microorganisms as food colorants and nutraceuticals to improve human health and production sensory properties.