Pengcheng Fu - State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haiko, China
Maryam Akhoundian - Biology Department, Marine & Environmental Science Faculty, University of Mazandaran, Babolsar, Iran‎

Abstract In-vitro antioxidant activities of semi-purified methanolic extract of Lyengaria stellata and Padina boergesenii were evaluated using DPPH radical-scavenging activity and reducing power. Total phenolic contents (TPC) and total flavonoid contents (TFC) were also investigated. The acetone fraction of L. stellata contained the highest value (۱۲۶.۰۴±۸.۶۵ mg GAE/g) of TPC, and the highest concentration of TFC (۹۴±۰.۱۳ and ۸۲±۰.۰۹ mg GAE /g) was obtained in ethanol fractions of Lyengaria stellata and Padina boergesenii, respectively. The highest DPPH scavenging activity (۸۸.۵%) was observed in the acetone fraction of L. stellata (۱ mg/ml). The most significant reducing power was observed in the acetone fractions of both seaweeds at ۱۰۰ mg/ml concentration (۱.۱۳۰±۰.۰۴۰ and ۰.۸۳۹±۰.۰۱۰, respectively). Ethanol and acetone fractions of L. stellata showed the greatest antibacterial activity (۲۹.۶±۰.۵ and ۲۸.۰±۰.۷ mm, respectively) against Staphylococcus aureus. The minimum value of MIC was observed in acetone fractions of both seaweeds against S. aureus (۵۰.۷ and ۵۰.۸ µg/ml), while Salmonella enterica showed the highest resistance to seaweeds extracts according to the– highest MIC values (>۲۰۰ mg/ml) and the smallest IZ diameters. The extract of both algae showed considerable antioxidant activity according to DPPH radical scavenging activity and reducing power assays.

Antibacterial Activity, Antioxidant potential, Persian Gulf, Seaweeds, Lyengaria stellate, Padina boergesenii