Comparison of Two Extraction Methods from Sargassum angustifolium and Padina distromatic on their Pharmaceutical Applications

Abstract

In the present study, two extraction methods, including maceration and ultrasound, were performed to prepare extracts from two brown algae: Padina distromatic and Sargassum angustifolium. Then, it aimed to evaluate extraction efficiency, phytochemical constituents, antioxidant, anti-Alzheimer’s, anti-inflammatory, and antimicrobial activities of extracts. The phytochemical compositions of algal extracts characterized by gas chromatography-mass spectrometry revealed numerous active secondary metabolites in all aqueous extracts. While S. angustifolium extracted by sonication exhibited the maximum content of phenols and flavonoids, the maximum DPPH scavenging activity (IC50=43 mg/mL) was observed for P. distromatic extract prepared by maceration. Moreover, P. distromatic extract prepared by sonication (UPE) provided the highest acetylcholinesterase inhibitory activity and strongest inhibition against nitric oxide production (2.0±0.3%), compared to other extracts. The antimicrobial activity was appraised against Staphylococcus aureus, Listeria innocua, Escherichia coli, and Salmonella typhi, through the well diffusion agar, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) methods. The maximum diameter of the inhibition zone (18.30 mm at 200 mg/mL), minimum MIC, and MBC were obtained with UPE against all selected bacteria, particularly S. aureus. Collectively, the obtained results provide valuable evidence for antioxidant, anti-Alzheimer, and antimicrobial activity driven by P. distromatic and S. angustifolium, which can highlight their possible approaches in therapeutic utilization.

Keywords

• ache inhibitory activity
• antimicrobial activity
• antioxidants
• brown marine algae