Comparison Between Extraction Procedures for the Recovery of Polyfunctionalized Biohopanoids

Summary Four extraction procedures (i.e., Bligh and Dyer, direct acetylation, CH2Cl2/CH3OH extraction and methanolysis) were tested for the recovery of biohopanoids from bacterial cells of a model bacterium (K. xylinus) and yielded similar amounts of bacteriohopanetetrols whatever the procedure used, without significant loss in the aqueous phase in the case of the Bligh and Dyer extraction. In contrast, the recovery of composite bacteriohopanepolyols (cyclitol ether derivatives) was shown to depend on the procedure used, with harsher conditions (i.e., methanolysis and direct acetylation) leading to higher yields. In the case of the Bligh and Dyer extraction, a significant part of the composite biohopanoid pool is lost in the aqueous phase, suggesting that the latter procedure should be avoided if optimal extraction of composite hopanoids is required.