外源添加剂对微藻生长和高价值生物产物积累的影响

Effects of exogenous additives on growth and high-value bioproducts accumulation of microalgae

摘要:

近年来，随着合成生物学的飞速发展，基因工程和分子操作手段日益完善。微藻作为微生物细胞工厂的代表性宿主菌株之一，在生产油脂、色素、蛋白质和生物燃料等高附加值生物产品方面得到了广泛的应用，并在生化能源、食品药品以及环境保护等领域展现出广阔的应用前景。然而，目前基于微藻工艺的生产效率仍然很低，限制了其大规模的工业应用。除了改良菌种和优化培养外，基于外源化学添加剂进行调控也是一种有益的优化策略。这种方法依赖于直接的表型筛选，不需要深入解析生物产品合成过程中涉及的代谢和分解代谢途径中的分子靶点，就可以快速提高微藻高附加值生物产品的产量，获得所需的表型。虽然已有大量关于使用外源添加剂等替代手段来提高微藻生长和高附加值生物产品的产量的研究，但关于添加剂的种类、用途和所针对的菌株以及相关的分子作用机制的分类总结还不够系统和全面。本综述对近年来应用化学诱导剂或增强剂来改善微藻培养中细胞生长和高附加值生物产物积累的实例进行总结，重点介绍了用于微藻培养的外源添加剂的种类、外源添加剂及其组合对微藻生长和高价值生物产品积累的影响以及相关作用的分子机制，为研究人员利用合成生物学的方法来开发合适的细胞底盘以及利用微藻来进行大规模的工业化生产提供了有用的信息。

Abstract:

With the rapid development of synthetic biology, genetic engineering, and molecular manipulation methods in recent years, microalgae, as representatives of microbial cell factories, have been widely used as hosts in the production of high-value bioproducts, such as oils, pigments, proteins, and biofuels, demonstrating promising prospects of application in biochemical energy, food and drugs, and environmental protection. Despite these advancements, the low production efficiency of microalgae limits their industrial application. In addition to strain improvement and culture condition optimization, the regulation by exogenous chemical additives serves as a promising optimization strategy. This method relies on straightforward phenotypic screening and circumvents the necessity for intricate understanding of molecular targets in the metabolic and catabolic pathways involved in the synthesis of bioproducts. It enables rapid yield increasing of high-value bioproducts from microalgae and obtaining the required phenotypes. Although studies have reported the use of alternatives means such as exogenous additives to improve the growth of microalgae and the yield of high-value bioproducts, the classification and summarization of the types, applications, targeted strains, and molecular mechanisms of these additives are not comprehensive. Here, we review the studies using chemical inducers or enhancers to improve cell growth and high-value bioproduct accumulation in microalgae in recent years. This paper focuses on the types of exogenous additives, the effects of exogenous additives and their combinations on microalgae growth and high-value bioproduct accumulation, and the molecular mechanisms of related effects. We aim to provide information for researchers to use methods of synthetic biology to develop suitable cell chassis and harness microalgae for industrial production.