Biotechnology Advances in Natural Food Colorant Acylated Anthocyanin Production

The food application of natural blue colorants such as acylated anthocyanin is becoming increasingly popular due to their safety, nutritional value, organoleptic attributes, and more pH/thermo-stable properties compared to nonacylated anthocyanins. However, it is a great challenge to obtain enough acylated anthocyanins to meet market demand, rather than readily available in nature from edible fruits and vegetables. In this review, the acylated anthocyanins in food crops, the efficient and eco-friendly extraction of food-grade acylated anthocyanins, and their potential application in intelligent packaging are extensively summarized. Subsequently, the plant anthocyanin acyltransferases (AATs) are also comprehensively summarized. The strategy of functional optimization of AATs through computational or artificial intelligence–based protein-directed evolution is described and suggested. Additionally, the advantages and disadvantages of acylated anthocyanins generated in microbes and plant suspension cells are extensively compared, and the chassis selection of engineering acylated anthocyanins is discussed. Finally, the approaches and strategies of metabolic engineering to enhance the yield of acylated anthocyanins in plant suspension cells are also described and discussed. Taken together, this review provides a roadmap or strategy for the production of acylated anthocyanins to meet the increasing market demand in future food industry.