Transgenic eukaryotic microalgae as green factories: providing new ideas for the production of biologically active substances

Abstract

Eukaryotic microalgae are important primary producers in nature that play an important role in the energy cycle of nature. The eukaryotic microalgae are also regarded as potential bioactive substance producers. In recent years, with the aid of genetic engineering, eukaryotic microalgae have found a wider range of potential applications in medicine, food, health products, cosmetics, and environmental protection. This article reviews the state of the art of microalga genetic engineering from the aspects of gene transfer system, gene editing technology, and screening method, with examples of the enhancement of lipids, carotenoids, polysaccharide, and functional proteins. Potential application scenarios of microalga genetic engineering and their products in the field of food and medicine are also highlighted. Furthermore, strategies for protein expression optimization in eukaryotic microalgae are reviewed. The existing shortcomings of eukaryotic microalga genetic engineering are also analyzed and highlighted.