Metabolite profiling-based characterization and antibacterial activity of sea cucumber Isostichopus sp. aff. badionotus from the Colombian Caribbean Sea.

ObjectiveMarine organisms such as sea cucumbers represent valuable sources of specialized metabolites with promising applications, making them relevant targets for exploring metabolite distribution and subsequent in-depth characterization. This study aimed to chemically and biologically characterize the parent methanolic extract and its derived fractions, obtained through sequential liquid-liquid partitioning, from the sea cucumber Isostichopus sp. aff. badionotus collected from the Colombian Caribbean Sea.MethodsThe extract and fractions were analyzed using ultra-high-performance liquid chromatography coupled with mass spectrometry and the Global Natural Products Social-based molecular networking platform, enabling dereplication and identification of metabolites. Additionally, the extract and fractions were evaluated against eight Gram-positive and Gram-negative bacterial strains using broth microdilution assays.ResultsThe dichloromethane fractions exhibited the highest antibacterial activity against both Gram-positive and Gram-negative bacteria. For the first time, chemical characterization allowed the identification of a series of metabolites present in the extract and fractions.ConclusionThis study provides the first report on antibacterial activity in I. sp. aff. badionotus, demonstrating that medium-polarity compounds in the dichloromethane fraction exhibited moderate bacterial inhibition, particularly against Gram-positive strains.