Comparison of LC-MS analysis of the F16 sub-fractions obtained from the RP-HPLC and their effect on the A549 cell viability.

Sub-fractionation of F16 fraction using RP-HPLC. F3 to F7 were each collected for 2 min, F8 for 5 min, F9 for 10 min and F10 for 6 min. Each fraction was evaporated and the dried material was dissolved in 50 µl PBS-DMSO 12%. The final concentration of DMSO in the assay medium was 1.2%. The cell viability was measured by the MTT assay described in the Materials and Methods after exposing A549 cells to the metabolites for 48 h. The effect of 1.2% DMSO was used as negative control. For each metabolite, the figures are arbitrary units indicating its elution profile, 100 corresponding to the maximum normalized level measured by the LC-MS sensor. nd means not detectable.*m/z in positive mode electrospray ionization.