Identification of bioactive components and antibacterial activity of Ulva lactuca extracts

Abstract

Investigating seaweeds to identify their bioactive compounds for broader applications has gained significant importance. The present research aimed to evaluate the antibacterial activities of different extracts of Ulva lactuca. Gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared (FT-IR) were used to characterize the chemical constituents, while antibacterial activity was performed to confirm the biological potential of the extracts. FT-IR analysis of Ulva lactuca revealed the presence of valuable functional groups such as alkenes, phenols, aliphatic amines, alkanes, alcohols, carboxylic acids, and aromatic compounds. GC-MS analysis displayed distinct peaks indicating the presence of phytochemicals with various medicinal effects. The major identified components are neophytadiene (22.28%), linoleic acid (22.78%), Z, Z-2,28-heptagonalactonediene (12.46%), phytol (13.02%), and 1,2-benzenedicarboxylic acid (8.38%), among other bioactive compounds detected in methanol, chloroform, and hexane extracts. The three extracts were evaluated against seven bacterial strains, with Staphylococcus aureus and E. coli showing the highest sensitivity. These findings suggest that green seaweed extracts hold strong potential as natural and eco-friendly biocontrol agents, offering novel strategies for managing bacterial infections and improving microbial control practices in healthcare, agriculture, and environmental applications.