Comparison of Quenching and Extraction Methods for Metabolome Analysis of Vibrio Parahaemolyticus
A reliable cell quenching and metabolite extraction method was crucial for microbial metabolism analysis.For metabolism analysis of Vibrio parahaemolyticus,liquid nitrogen and 75% methanol(-80 ℃) were compared for their efficiency of cell quenching,and six different extraction solvents based on(i) chloroform,(ii) 75% cold methanol,(iii) water,(iv) methanol:chloroform:water=10∶3∶1(V/V),(v) methanol:chloroform:water=3∶1∶1(V/V) and(vi) methanol∶chloroform=1∶1(V/V) were compared for their efficiency of metabolites extracting.The metabolites were detected by GC-MS.The results showed that leakage of metabolite occurred when quenched with 75% methanol(-80 ℃);however this phenomenon did not occur with liquid nitrogen.47 metabolites were found when extracted with 75% cold methanol,and the relative standard deviation of peak area was 8.0%.In contrast,40 or less metabolites were detected with other extraction methods,and the reproducibilities of those methods were unsatisfactory.For global analysis,quenching with liquid nitrogen and extraction with 75% cold methanol was very suitable for metabolomics studies of Vibrio parahaemolyticus.