Angiotensin-converting enzyme I inhibitory activity of phlorotannins from Ecklonia stolonifera

Abstract

As part of our study of the isolation of antihypertensive agents derived from natural marine products, the bioactivity of 10 edible Korean seaweeds were screened by angiotensin converting enzyme (ACE) inhibitory and peroxynitrite assays. Among the crude extracts of selected seaweeds, including five Phaeophyta ( Ecklonia stolonifera , E. cava , Pelvetia siliquosa , Hizikia fusiforme , and Undaria pinnatifida ), four Rhodophyta ( Gigartina tenella , Gelidium amansii , Chondria crassicaulis , and Porphyra tenera ) and one Chlorophyta ( Capsosiphon fulvescens ), the ethanol extracts of E. stolonifera , E. cava , P. siliquosa , U. pinnatifida , and G. tenella exhibited significant inhibitory properties against ACE at more than 50% inhibition at a concentration of 163.93 µ g/mL. Phloroglucinol 1 , eckstolonol 2 , eckol 3 , phlorofucofuroeckol A 4 , and dieckol 5 had been isolated previously, and triphlorethol-A 6 and fucosterol 7 were isolated for the first time from E. stolonifera. Also, the ACE inhibitory and peroxynitrite scavenging properties of phlorotannins 1-6 were evaluated, along with fucosterol 7 obtained from E. stolonifera . Among profound peroxynitrite scavenging compounds 1-6 , phlorotannins 3 , 4 and 5 were also determined to manifest marked inhibitory activity against ACE, with 50% inhibition concentration (IC 50 ) values of 70.82 ± 0.25, 12.74 ± 0.15, and 34.25 ± 3.56 µ M, respectively.

Angiotensin-converting enzyme (ACE) inhibitory potential of standardizedMucuna pruriensseed extract

“…Screening of antihypertensive effects in traditional medicines has been performed over many years and the number of compounds from plants has been identified to possess ACE inhibition activity, including hydrolysable tannins, phenylpropanes (Jung et al, 2006), proanthocyanidins, flavonoids, xanthones, fatty acids, terpenoids alkaloids, oligosaccharides, and peptide amino acids. Plants belonging to the families Acanthaceae, Aloaceae, Amranthaceae, Apiaceae, Apocynaceae, Asclepiadaceae, Bignoniaceae, Combretaceae, Caesalpin1aceae, Fabaceae, Lamiaceae, Malvaceae, Moringaceae, Oleaceae, Piperaceae, Rutaceae, Verbinaceae, Zingiberaceae, and Zygophyllaceae have been reported to have ACE inhibition potential (Braga et al, 2007).…”

“…Angiotensin-converting enzyme (ACE, peptidyl-dipeptide hydrolase EC 3.4.15.1) is a zinc-containing metalloenzyme, located mainly in the endothelial lining of the vasculature of the lung and plays a vital role in the pathogenesis of hypertension, cardiovascular, and renal diseases (Jung et al, 2006). ACE increases the blood pressure by the hydrolysis of the rennin-induced decapeptide, angiotensin I to octapeptide angiotensin II, a potent vasoconstrictor (Williams et al, 1997).…”

Cosmeceuticals Derived from Bioactive Substances Found in Marine Algae

“…Fucosterol (Figure 1) is a steroidal terpenoid extracted from Phaeophyta marine algae (Ecklonia stolonifera, Pelvetia siliquosa, Sargassum carpophyllum) [10][11][12]. Fucosterol is usually obtained as a primary compound from the non-polar fraction of algae extract [10].…”

“…Fucosterol (Figure 1) is a steroidal terpenoid extracted from Phaeophyta marine algae (Ecklonia stolonifera, Pelvetia siliquosa, Sargassum carpophyllum) [10][11][12]. Fucosterol is usually obtained as a primary compound from the non-polar fraction of algae extract [10]. This compound shows strong antioxidant activity by increasing the concentration of antioxidant enzymes Superoxide Dismutase (SOD), catalase and glutathione peroxidase (GSH-px), enzymes that are involved in the fine control of cellular H 2 O 2 concentration.…”

Ecklonia stolonifera inhibits lipopolysaccharide-induced production of nitric oxide, prostaglandin E2, and proinflammatory cytokines in RAW264.7 macrophages

“…It has been previously reported that E. stolonifera harbors several bio-active compounds, including fucosterol, 24-hydroperoxy 24-vinylcholesterol, phloroglucinol, eckstolonol, eckol, phlorofucofuroeckol-A, dieckol, triphlorethol-A, 2-phloroeckol and 7-phloroeckol, which function as antioxidants . This algae has also been shown to exhibit angiotensin-converting enzyme I inhibitory activity (Jung et al 2006), total reactive oxygen species generation inhibitory activity (Kang et al 2004a), aldose reductase inhibitory activity (Jung et al 2008), antidiabetic, antioxidant and anti-hyperlipidemic effects (Lee et al 1996;, hepatoprotective activity , inhibitory effects on MMP-1 expression (Joe et al 2006), anti-tyrosinase activity (Kang et al 2004b), and acetyland butyryl-cholinesterase inhibitory activities . Additionally, several researchers have studied the antimicrobial effects of phloroglucinol derivatives .…”