Time effects on extractable metabolites. Venn Diagram of the results of the extraction with a mixture of 2:1 methanol:dichloromethane and three extraction durations of 0 h (21.0 h), 1 day (21.1 d) and 1 week (21.1 w), respectively. In brackets the total number of metabolites of the single samples is given. 452 metabolites were found in every sample. For details of extraction see legend of Table 3.