The issue of reducing or removing phospholipids from total lipids of a microalgae and an oleaginous fungus for preparing biodiesel

Abstract

ABSTRACTThis study is divided into three parts and examines recommendations made in the literature to remove or reduce phospholipids, a class of polar lipids, from microalgal and fungal lipids, so that transesterification of the neutral lipids with methanol improves the yield of fatty acid methyl esters (FAME) (biodiesel). Literature on the role of phospholipids lowering the yield of FAME during transesterification of vegetable oils is reviewed in the first part of this study. The second part of this study scrutinizes two published papers on the preparation and yield of FAME by transesterification of total lipids present in microalgae of Chlorella pyrenoidosa (CP) and oleaginous fungus Mucor circinelloides (MC) with or without biomass in different solvent systems. Mole balance between acyl groups present in total lipids of CP and MC with methanol in part 3 makes it possible to use the results reviewed in part 1 of reduction in the yield of FAME in vegetable oils due to phospholipids and excess methanol. In conclusion, it is recommended to separate neutral lipids from polar lipids/phospholipids present in the total lipids of microalgae and fungi by supercritical carbon dioxide to prepare FAME in improved yields and keep phosphorus content below the polluting limit in the biodiesel prepared.