Genomic and functional characterization of a lipopeptide-producing endophytic Bacillus velezensis EL isolated from Euphorbia cyparissias L

Lipopeptides, are emerging as sustainable alternatives to synthetic surfactants due to their biodegradability, low toxicity, and broad application in bioremediation, agriculture, and medicine. Endophytic microorganisms, especially those adapted to degraded environments, represent a valuable and underexplored reservoir of such bioactive compounds. Euphorbia cyparissias L., known as pine spurge, is a perennial herbaceous plant from the Euphorbiaceae family, and is highly resistant to environmental stresses, which may result from the presence of specialist endophytic microorganisms that support its adaptation. A novel endophytic strain, Bacillus velezensis EL, was isolated from surface-sterilized tissues of Euphorbia cyparissias L., a hardy plant growing in degraded soil. Preliminary screening revealed its high biosurfactant activity, including emulsification, oil dispersion, and surface tension reduction. Whole-genome sequencing and functional annotation identified thirteen biosynthetic gene clusters, including nonribosomal peptide synthetase pathways responsible for lipopeptide production. Fourier-transform infrared spectroscopy confirmed characteristic functional groups of lipopeptides, while ultra-performance liquid chromatography–mass spectrometry validated the presence of surfactin and bacillomycin homologs. Process optimization using the Taguchi design significantly enhanced production, yielding 3.841 g/L of crude biosurfactant under optimal conditions. The product exhibited strong surface activity, with high emulsifying and oil displacement performance, and favorable biochemical composition with high protein content. This study highlights Bacillus velezensis EL as a promising producer of lipopeptide biosurfactants. It also identifies Euphorbia cyparissias L. as a novel and ecologically significant host plant harboring endophytes with industrial biotechnological potential. These findings support further development of endophyte-based systems for sustainable biosurfactant production.