LC-MS/MS Identification of Novel Saponins from the Viscera of Sea Cucumber Apostichopus japonicus

Sea cucumbers, soft-bodied wormlike echinoderms, are traditionally consumed in China. Sea cucumber viscera are often discarded during production. In this study, we characterized saponins present in the viscera of the Chinese sea cucumber Apostichopus japonicus. Sea cucumber saponins were obtained by a two-stage process consisting of foam fractionation and macroporous resin separation. Furthermore, the saponins were characterized by HPLC-Q-TOF-MS. Three novel saponins, i.e., apostichoposide A–C, were detected and characterized based on their unique fragmentation patterns in the negative ion mode tandem MS spectra as well as isolation and NMR studies. The abundance of saponins in sea cucumber viscera holds promise for industrial applications.