Highest accumulated microalgal lipids (polar and non-polar) for biodiesel production with advanced wastewater treatment: Role of lipidomics.

• Report the highest accumulated lipids content (≥40%) microalgal species till 2019. • Wild microalgal strains exhibit high accumulative lipid content. • Advanced abiotic stress induced the microalgal growth and lipid content. • High lipid content microalgae supported the advanced wastewater treatment. • Lipidomics direct suitable engineered microalgal strain for high lipid content. Microalgal lipids consist of non-polar and polar lipids. Triacyleglyceride (TAG), a non-polar lipid, is convertible to biodiesel, whereas glycolipids and phospholipids are polar and not convertible to biodiesel owing to their high degree of unsaturation (polyunsaturated fatty acids), which makes the production process insufficient and expensive. In this review, microalgal species that contain the highest lipid content (≥40%) in the literature till 2019 are highlighted. The differentiation between non-polar and polar lipids and the limitations in the conversion of polar lipids to biodiesel are reported. The basic and advanced factors contributing to the accumulation of lipids convertible to biodiesel is discussed. Microalgal species including Scenedesmus obliquus , Ourococcus multisporus , Chlamydomonas pitschmannii , Micractinium reisseri , and Botryococcus braunii with high lipid content are potential candidates for biomass/biodiesel production and nutrient removal from wastewater. Application of lipidomics and transcriptomics to manipulate the lipid associated gene acetyl-CoA synthetase in microalgae improves the accumulative lipid content. [ABSTRACT FROM AUTHOR]