Exploring bioactive fraction of Sargassum wightii: In vitro elucidation of angiotensin-I-converting enzyme inhibition and antioxidant potential

Abstract

Bioactive fraction of brown algae Sargassum wightii (SWE) was obtained using silica column chromatography and preparative Thin Layer Chromatography (TLC). FT-IR and LC–mass spectrometry ESI analysis revealed presence of various phlorotannins in the SWE. The IC50 value of SWE was found to be 59.91, 51.04, and 55.21 μg/ml for scavenging of 2,2-diphenyl-1-picrylhydrazyl, 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid), and Ferric Reducing Antioxidant Power assay, respectively. SWE inhibited angiotensin-I-converting enzyme (ACE) in mixed-type manner with IC50 value of 56.96 µg/ml and Ki value of 45 µg/ml. The dual function such as antioxidant and ACE inhibition of SWE warrants further study to understand the antihypertensive potential in vivo.

Keywords

• Sargassum wightii
• Phlorotannin
• antioxidant
• angiotensin-I-converting enzyme
• mixed-type inhibition