Advances in mechanical cell disruption for algal biofuel: A decade of progress toward industrial integration

The global transition toward renewable energy has accelerated the search for sustainable alternatives to fossil fuels, positioning algae as a promising feedstock for biofuel production. Microalgae, in particular, stand out due to their high lipid content, rapid growth rates, and ability to thrive in diverse environments, including saline and wastewater systems. Despite these advantages, effective disruption of their robust cell walls remains a critical barrier to accessing intracellular components such as lipids, proteins, and carbohydrates. This barrier limits energy efficiency, scalability, and overall economic viability. Over the past decade, researchers have developed several physical-mechanical disruption methods, including ultrasonication (US), bead milling (BM), and high-pressure homogenization (HPH), to address these challenges. For example, BM has increased lipid yields by four to five times compared to untreated cells, while combining US with HPH has reduced energy consumption by ∼50 %, achieving ∼105.6 kJ/g dry matter. Microwave (MW) treatment has also demonstrated lipid recoveries of up to 73 % using water as a solvent, highlighting its potential as an energy-efficient technique. This review evaluates recent advancements in physical-mechanical disruption technologies, with a focus on their efficiency, energy demands, and scalability. By contrasting these methods with conventional chemical and enzymatic approaches, the study highlights innovations that enhance lipid extraction and streamline biofuel production while reducing environmental and economic drawbacks. The review identifies key research gaps and offers direction for future development and practical implementation. Finally, this recent study suggests incorporating advanced disruption tactics into commercial systems to make algae-based biofuels an appealing alternative to low-carbon energy.