Advancement in microalgal metabolites extraction techniques: Multi-factorial considerations

Area of Science:

• Biotechnology
• Green Chemistry
• Phycology

Background:

• Microalgae are valuable sources of lipids, pigments, proteins, and polysaccharides.
• Cell wall complexity and high processing costs hinder metabolite recovery from microalgae.

Purpose of the Study:

• To review and comparatively analyze advanced green extraction techniques for microalgal metabolites.
• To assess extraction efficiency, cost, scalability, and environmental impact of various methods.

Main Methods:

• Evaluation of enzyme-assisted (EAE), ionic liquid (ILs), microwave-assisted (MAE), milking, pressurized liquid (PLE), pulsed electric field (PEF), supercritical fluid (SFE), and ultrasound-assisted extraction (UAE).
• Multi-factorial comparative analysis of cost, scalability, efficiency, and environmental footprint.
• Assessment of integrated extraction approaches.

Main Results:

• Enzyme-assisted extraction (EAE) and supercritical fluid extraction (SFE) yield up to 97% but are expensive.
• Ultrasound-assisted extraction (UAE) and pulsed electric field (PEF) offer a balance of scalability and sustainability.
• UAE can reduce extraction time by up to 60% compared to conventional methods.
• Integrated methods (e.g., ILs + SFE, UAE + EAE) show synergistic benefits, improving yield and reducing solvent use.

Conclusions:

• The choice of extraction strategy depends on industrial priorities like cost, yield, and sustainability.
• Advanced green extraction techniques are crucial for the sustainable commercialization of microalgal metabolites.
• Integrated approaches present a promising avenue for optimizing metabolite recovery.