Phenolic compound derived from Enteromorpha intestinalis and their bioactivity against bacterial pathogens

Abstract

The purpose of the study was to assess a phenolic compound that was extracted from the brown seaweed Enteromorpha intestinalis (Linn.), Nees (1820) for its antibacterial activities on different bacterial pathogens of fish illnesses. Hexane and methanol were utilized to extract bioactive compounds from the seaweed. Phytochemical analysis of the methnaolic extracts have revealed the presence of carbohydrates and glycosides, saponins, alkaloids, amino acids, flavonoids, fixed oil and fat, phenol compounds, tannins, and steroids. The bacterial pathogens of fish, including Providencia vermicola, Aeromonas hydrophila, Vibrio harveyi, and Aeromonas caviae, were targeted for antibacterial assessment. Among them, the methanolic crude extract and fraction-1 of E. intestinalis have shown maximum activity against A. hydrophila (22 ± 0.13 and 33 ± 0.56 µg/mL). Column chromatography was employed to isolate effective seaweed fraction, while FT-IR and HPLC were utilized for characterization. The phytochemical analysis confirmed the presence of various compounds in both extracts. The crude methanolic extract of E. intestinalis have demonstrated the maximum efficacy beside the tested bacterial pathogens. The FT-IR analysis revealed functional groups associated with polymeric structures in the seaweed extracts, including alcohols, phenols, aromatics, alkyl halides, aliphatic amines, alkynes, and alkenes. Overall, the methanolic extract of E. intestinalis exhibited significant antibacterial activity as a result of the phenolic chemicals that are present. The study provides valuable baseline data, emphasizing the need for further research towards developing antibacterial drug formulations.