Lutein biosynthesis from microalgae — Recent advances and circular economy
Yoong Kit Leong, Jo‐Shu Chang
Abstract
Lutein, one of the primary xanthophylls, has garnered much attention due to its numerous bioactivities, including antioxidant, eye protection as well as amelioration or prevention of diseases with a huge range of applications in feed and food, nutraceutical, pharmaceutical, and cosmeceutical industries. As a lutein producer, microalgae demonstrated immense potential as an alternative to marigold flower, the commercial source of lutein production due to numerous advantages, including a fast growth rate, no seasonal harvesting limitation, and higher lutein content and productivity. Circular economy of lutein production from microalgae can be achieved via resource recovery of abundant and low-cost byproducts or waste streams. Microalgal lutein biosynthesis is influenced by operation parameters, including temperature, light quality, salinity, and culture medium composition. Among different operation strategies, innovative two-stage cultivation approaches have been developed to maximize lutein yield from microalgae. Such strategies include a combination of different modes of nutrition (photoautotrophic, heterotrophic, mixotrophic), integration with fed-batch and/or semi-continuous cultivation mode, as well as thermal- or light-shifting operations. Furthermore, the discussion on pilot-scale studies of microalgae cultivation has been provided to give insights and bridge the gap between laboratory-scale studies and commercial-scale operations.