In vitro Assessment of Bioactivities of Seagrass and its Zinc Oxide Nanoparticles

Abstract

Background: Halophila beccarii, a seagrass dwelling in shallow coastal water belongs to the family Hydrocharitaceae, is well-known for its wide spectrum of bioactive secondary metabolites, including phenolics, flavonoids, terpenoids and sulphated polysaccharides. In the current study, we explored the anti inflammatory, antioxidant and the antimicrobial activities of aqueous extract of Halophila beccarii and its zinc oxide nanoparticles (Hb-ZnO NPs). Methods: The aqueous extract prepared from H.beccarii  was utilized for the synthesis of zinc oxide nanoparticles by green technology. The anti inflammatory, antioxidant and antibacterial activity of both aqueous extract and zinc oxide nanoparticles was determined by membrane stabilization assay, radical scavenging activity and the disc diffusion method respectively. Results: Both aqueous extract and zinc oxide nanoparticles exhibited significant antioxidant, membrane stabilization effects when correlated with the standard drug such as ascorbic acid and diclofenac. Hb-ZnO NPs showed nearly identical activity to Diclofenac, with inhibition values of 65.41% and 70.14% respectively at 80 µg/ml. Hb-ZnO NPs showed strongest antibacterial effect, producing inhibition zones of 24.6 ± 0.5 mm against B.subtilis, 18 ± 0.1 mm against P. aeruginosa, 19.66 ± 0.5 mm against K.pneumoniae, and S.aureus  14 ± 0.5 mm, closely matching the activity of the standard antibiotic gentamycin. Conclusion: The study demonstrated superior therapeutical potential of zinc oxide nanoparticles compared to aqueous extract of H.beccarii.