Marine ecosystems harbor a vast reservoir of microorganisms capable of producing novel bioactive compounds with environmental and agricultural significance. In this study, marine water samples collected from the mid-sea region of Machilipatnam, Andhra Pradesh, were screened for biosurfactant-producing bacteria using enrichment culture techniques with kerosene as the sole carbon source. Ten distinct isolates (I₁–I₁₀) were obtained and screened through multiple qualitative and quantitative assays. Among them, isolate I₅ demonstrated the highest emulsification index (60.6%), maximum biosurfactant yield (340 mg/L), and significant surface tension reduction (from 40 to 25 mN/m within 48 h), highlighting its potent lipopeptide biosurfactant production. Morphological and staining analyses revealed that isolate I₅ is a Gram-positive, spore-forming, rod-shaped, and capsulated bacterium. Biochemical tests suggested its affiliation with the genus Fictibacillus, which was confirmed through 16S rRNA gene sequencing and phylogenetic analysis, identifying the strain as Fictibacillus enclensis strain 5 (GenBank Accession No. PQ864798). Antifungal activity assays revealed 55% and 70% inhibition against Macrophomina phaseolina and Sclerotium rolfsii, respectively, indicating its biocontrol potential. FTIR spectral analysis confirmed the presence of functional groups characteristic of cyclic lipopeptides like surfactin and iturin. These findings demonstrate the potential of Fictibacillus enclensis strain 5 as a sustainable biotechnological candidate for biosurfactant production and fungal pathogen control.
Keywords: Marine bacteria; Fictibacillus enclensis; Biosurfactant; Lipopeptide; Surface tension; FTIR; Antifungal activity
How to cite this article: Megavath VS, Atmika M, Boddu S, Krishnaiah, K M.; Isolation and Molecular Characterization of Marine-Derived Fictibacillus enclensis Strain 5: A Potent Biosurfactant Producer with Antifungal Activity...Int J Drug Deliv Technol. 2026;16(1s): 524-532; DOI: 10.25258/ijddt.16. 524-532