Advanced Strategies for the Efficient Production of Squalene by Microbial Fermentation

Squalene is an isoprene compound, which shows excellent properties, such as antioxidant and anticancer and so on. Currently, squalene has been widely used in medicine, cosmetics, vaccine adjuvants, and other fields. The traditional methods for squalene production mainly include natural extraction and chemical synthesis, which cannot meet the increasing market demand. Squalene production through microbial fermentation has become a promising alternative owing to its high efficiency and environmental friendliness. To improve the squalene production, a series of strategies including metabolic engineering and fermentation optimization and so on have been recruited. Accordingly, this review will comprehensively discuss various strategies including the isolation of high squalene producer, metabolic regulation of synthetic pathway and process optimization to improve the synthetic efficiency of squalene. Challenges and future perspectives for microbial squalene synthesis were also proposed.