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Two linear proline-rich peptides (<b>1</b>–<b>2</b>), bearing an N-terminal pyroglutamate, were isolated from the marine bacterium <i>Microbacterium</i> sp. V1, associated with the marine sponge <i>Petrosia ficiformis</i>, collected in the volcanic CO₂ vents in Ischia Island (South Italy). Peptide production was triggered at low temperature following the one strain many compounds (OSMAC) method. Both peptides were detected together with other peptides (<b>3</b>–<b>8</b>) via an integrated, untargeted MS/MS-based molecular networking and cheminformatic approach. The planar structure of the peptides was determined by extensive 1D and 2D NMR and HR-MS analysis, and the stereochemistry of the aminoacyl residues was inferred by Marfey’s analysis. Peptides <b>1</b>–<b>8</b> are likely to arise from <i>Microbacterium</i> V1 tailor-made proteolysis of tryptone. Peptides <b>1</b> and <b>2</b> were shown to display antioxidant properties in the ferric-reducing antioxidant power (FRAP) assay.