Evaluation of metabolome sample preparation methods regarding leakage reduction for the oleaginous yeast Yarrowia lipolytica

Yarrowia lipolytica is the well-known oleaginous yeast able to accumulate amounts of lipids and a variety of high value products. The knowledge of its intracellular metabolites concentrations, which are directly linked to the sample preparation of corresponding intracellular metabolites, is of fundamental importance for the characterization of its metabolism. Therefore, in this study, we evaluated current sampling and extraction methods used in gas chromatography-mass spectrometry (GC-MS) analysis of the intracellular metabolites of microorganism. Mainly, the comparison between the methyl chloroformate (MCF) derivatization and the N-methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA) derivatization applied to the analysis of a broad variety of Y. lipolytica's metabolites was performed. More importantly, the dimethyl sulfoxide (DMSO) solution quenching method was attempted with the purpose of reducing the intracellular metabolites leakage during quenching and adapting the leakage-free quenching method to both kinds of derivatization. The results obtained showed that the DMSO quenching method permits measurement of the concentration of intracellular metabolites and can be applicable for the analysis of multiple metabolites of important pathways in Y. lipolytica by available routine GC-MS platform.