Comparison of LC-MS analysis of the fractions obtained from flash chromatography and their effect on the A549 cell viability.

Fractionation of bulk culture extracts using flash chromatography. To measure their toxicity, each 5 ml fraction was dried and solubilised in 500 µl in PBS-DMSO 40% and then diluted 10 fold in PBS-DMSO 12%. The final concentration of DMSO in the assay medium was 1.2%. The cells were exposed for 24 h before measuring the cell viability as described in the Materials and Methods. The effect of 1.2% DMSO was used as negative control. For each metabolite, the figures are arbitrary units indicating its elution profile with 100 corresponding to the maximum normalized level measured by the LC-MS sensor. nd means not detectable.