Optimising green extraction of microbial astaxanthin: Breakthroughs in cell disruption and sustainable production from Haematococcus lacustris

Astaxanthin (AXT) is a potent natural antioxidant that quenches singlet oxygen and scavenges free radicals, thereby reducing oxidative damage and contributing to disease prevention. AXT offers a broad range of industrial applications, attracting significant research interest. However, industrial-scale production is hindered by inefficient extraction, separation, and purification processes; a lack of standardised characterisation methods and real-time monitoring systems, limitations in the metabolic engineering of production strains; and interdisciplinary barriers. Here, we review the industrial production processes of natural AXT, with a focus on the cell wall structure of Haematococcus lacustris. We discuss recent advances and emerging trends in microalgae cell disruption techniques, particularly extraction and characterisation techniques reported in past five years. We also highlight limitations and future research directions. This review aims to provide a theoretical and practical guide for efficient, environmentally friendly AXT extraction and characterisation to explore its properties and applications.