Lipid Droplets from Plants and Microalgae: Characteristics, Extractions, and Applications

SIMPLE SUMMARY: Lipid droplets (LDs) are cellular organelles that are involved in diverse biological processes. They are composed of a neutral lipid core surrounded by a phospholipid monolayer membrane. LDs are found in many different types of cells and organisms, and play important roles in energy metabolism, signaling, and lipid storage. Recent research has led to a better understanding of the formation, turnover, and functions of LDs, as well as their potential applications in fields such as biofuels, food additives, and cosmetics. However, there are still many questions to be answered in order to fully exploit the potential of LDs, such as understanding the metabolic differences between species and strains, and uncovering the precise functions and relationships of LDs and their associated proteins. Moreover, extracting LDs from plants and microalgae for various applications remains a challenge, with different methods having different advantages and limitations, depending on the intended use. Consequently, further research into LDs could lead to innovative and sustainable solutions for a variety of industries and applications. ABSTRACT: Plant and algal LDs are gaining popularity as a promising non-chemical technology for the production of lipids and oils. In general, these organelles are composed of a neutral lipid core surrounded by a phospholipid monolayer and various surface-associated proteins. Many studies have shown that LDs are involved in numerous biological processes such as lipid trafficking and signaling, membrane remodeling, and intercellular organelle communications. To fully exploit the potential of LDs for scientific research and commercial applications, it is important to develop suitable extraction processes that preserve their properties and functions. However, research on LD extraction strategies is limited. This review first describes recent progress in understanding the characteristics of LDs, and then systematically introduces LD extraction strategies. Finally, the potential functions and applications of LDs in various fields are discussed. Overall, this review provides valuable insights into the properties and functions of LDs, as well as potential approaches for their extraction and utilization. It is hoped that these findings will inspire further research and innovation in the field of LD-based technology.