Pharmacological activities of brown seaweed Sargassum wightii (Family Sargassaceae) using different in vitro models

Recently a great deal of interest has been developed towards natural bioactive components from seaweeds as functional food ingredients. Antioxidant, anti-inflammatory, antidiabetic, and antihypertensive activities of ethyl acetate:methanol and chloroform solvent fractions of the brown seaweed Sargassum wightii were evaluated using different in vitro systems. The ethyl acetate:methanol fraction registered greater Fe²⁺ ion chelating ability (IC₅₀ 0.52 mg/ml), and were effective in stabilizing the 2,2-azino-bis-3-ethylbenzothiozoline-6-sulfonic acid (IC₅₀ 0.82 mg/mL), and 1,1-diphenyl-2-picryl hydrazil radicals (IC₅₀ 0.32 mg/mL) than those derived from chloroform solvent fractions. The chloroform solvent fraction showed greater angiotensin converting enzyme-I inhibitory activity (IC₅₀ 0.084 mg/mL), while the ethyl acetate:methanol fraction exhibited greater anti-COX-1, 2, and 5-LOX (IC₅₀ 0.03-0.05 mg/mL) and DPP-4 inhibitory (IC₅₀ ~ 0.013 mg/mL) properties. A significant co-linearity was recorded between target bioactive properties and the electronegative groups appeared in the downfield space of the nuclear magnetic resonance spectra of the ethyl acetate:methanol and chloroform solvent fractions from S. wightii.