Fig. 5

Qualitative analysis of S1P production in S1P-producing strain by ESI–MS. A ESI–MS spectra of sphingosine (up) and S1P (down) standards. B ESI–MS analysis of sphingolipids produced by S1P-producing strain. Fed-batch fermentation for S1P production was conducted in bioreactor with DDLAOgS strain. S1P was detected by ESI–MS at 12 h intervals