Deuterium-Labeled Precursor Feeding Reveals a New pABA-Containing Meroterpenoid from the Mango Pathogen Xanthomonas citripv. mangiferaeindicae

A new para-aminobenzoic-acid-containing natural product from the mango pathogenic organism Xanthomonas citripv. mangiferaeindicaeis described. By means of stable isotope precursor feeding combined with nontargeted LC-MS/MS, the generated spectra were clustered and visualized in a molecular network. This led to the identification of a new member of the meroterpenoids, termed xanthomonic acid, which is composed of an isoprenylated para-aminobenzoic acid. In vitrocytotoxicity assays demonstrated activity of xanthomonic acid against several human cancer cell lines by induction of autophagy.