Advancement of Abiotic Stresses for Microalgal Lipid Production and Its Bioprospecting into Sustainable Biofuels

The world is currently facing global energy crises and escalating environmental pollution, which are caused by the extensive exploitation of conventional energy sources. The limited availability of conventional energy sources has opened the door to the search for alternative energy sources. In this regard, microalgae have emerged as a promising substitute for conventional energy sources due to their high photosynthetic rate, high carbohydrate and lipid content, efficient CO2 fixation capacity, and ability to thrive in adverse environments. The research and development of microalgal-based biofuel as a clean and sustainable alternative energy source has been ongoing for many years, but it has not yet been widely adopted commercially. However, it is currently gaining greater attention due to the integrated biorefinery concept. This study provides an in-depth review of recent advances in microalgae cultivation techniques and explores methods for increasing lipid production by manipulating environmental factors. Furthermore, our discussions have covered high lipid content microalgal species, harvesting methods, biorefinery concepts, process optimizing software tools, and the accumulation of triglycerides in lipid droplets. The study additionally explores the influence of abiotic stresses on the response of biosynthetic genes involved in lipid synthesis and metabolism. In conclusion, algae-based biofuels offer a viable alternative to traditional fuels for meeting the growing demand for energy.