Current advances in microalgae-based fucoxanthin production and downstream processes.

Fucoxanthin, a marine carotenoid primarily found in brown algae and microalgae, offers significant health benefits, including antioxidant, anti-obesity, and anti-cancer effects. While brown algae remain the dominant commercial source, microalgae such as Phaeodactylum tricornutum are emerging as promising candidates for large-scale, sustainable fucoxanthin production. This review explores advancements in fucoxanthin biosynthesis, focusing on cultivation methods, extraction techniques, and genetic engineering strategies. Different cultivation systems - including autotrophic, heterotrophic, and mixotrophic approaches - have been assessed for their biomass yield, cost-effectiveness, and scalability, together with a quantitative meta-analysis to highlight specific trends or correlations in fucoxanthin production. The efficiency and environmental impact of extraction methods, such as supercritical fluid extraction, ultrasound-assisted extraction, and microwave-assisted extraction, have also been evaluated. In addition, synthetic biology and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-based genetic modifications show potential for enhancing fucoxanthin biosynthesis. However, challenges remain in terms of cost, scalability, and regulatory constraints. This review highlights the need for integrated biotechnological solutions to enhance commercial viability, combining metabolic engineering, efficient extraction techniques, and optimized cultivation strategies. As demand continues to grow in the nutraceutical, pharmaceutical, and cosmetic industries, ongoing advancements in microalgae-based fucoxanthin production will be critical for ensuring sustainable and cost-effective manufacturing.