Brown Algae (Phaeophyceae) from the Coast of Madagascar: preliminary Bioactivity Studies and Isolation of Natural Products

Abstract

Eight species of brown algae (Phaeophyceae) from the coast of Madagascar have been investigated for their chemical constituents. Fucosterol (3) was obtained as the most abundant compound. The brown alga Sargassum ilicifolium was the source for the first isolation of the terpenoid C27-alcohol 1,1′,2-trinorsqualenol (1) from marine sources. From S. incisifolium we isolated the highly unsaturated glycolipid 1-O-palmitoyl-2-O-stearidonoyl-3-O-β-D-galactopyranosylglycerol (4) and we report the first full assignment of its 1H and 13C NMR data. Apo-9′-fucoxanthinone (8) along with 24-ketocholesterol (5), (22E)-3β-hydroxycholesta-5,22-dien-24-one (6), and saringosterol (7) were obtained from Turbinaria ornata. The crude extracts of all eight species of brown algae exhibited a pronounced antimicrobial activity against the Gram-positive bacteria Bacillus cereus, Staphylococcus aureus, and Streptococcus pneumoniae.Graphical AbstractElectronic supplementary materialThe online version of this article (doi:10.1007/s13659-015-0068-0) contains supplementary material, which is available to authorized users.

Isolation and structure elucidation of natural products of three soft corals and a sponge from the coast of Madagascar

“…In continuation of our studies on the chemical constituents of marine organisms from the coast of Madagascar including red algae, 1 brown algae, 2 and soft corals, 3 we herein turned our attention to soft corals of the species Sarcophyton stellatum, Capnella fungiformis, and Lobophytum crassum. A sponge of the species Pseudoceratina arabica has also been included in the present investigation.…”

Antibacterial Use of Macroalgae Compounds against Foodborne Pathogens

“…is acid resistant, salt-tolerant and can survive at infective levels in many types of foods such as fruits and vegetables, low pH foods, prepared foods and foods held in a modified atmosphere or vacuum packaging [ 85 ]. Studies involving brown algal extracts against S. flexneri were conducted [ 76 , 88 ] and the majority of the tested algae species belonged to the Sargassum taxa, as shown in Table 2 . From observing Table 2 , we can notice that all the antimicrobial test results were attained by Kirby–Bauer test and presented no quantitative results.…”

“…Relating to Phaeophytha phylum, Sargassum spp. was the most studied genus [ 41 , 57 , 73 , 76 , 99 , 118 , 129 , 130 ]. Comparing solvent performance for bioactive compounds extraction, the following results were obtained: ethanol or acetone > crude extract or MeOH/DCM for D. membranacea [ 28 ], EtOAc > EtOH > hexane, DCM, n-BuOH, water (H 2 O) for E. cava [ 109 ]; EtOAc > DCM, BuOH> hexane > MeOH for E. bicyclis [ 121 ]; H 2 O > MeOH, acetone or ethyl acetate for F. serratus [ 131 ]; ethanol > hexane > H 2 O for H. elongata [ 21 ]; ethylacetate > MeOH for P. antillarum and P. boergeseni [ 66 ]; MeOH > acetone for S. platycarpum and for S. latifolium [ 118 ].…”

One-Step Preparative Separation of Phytosterols from Edible Brown Seaweed Sargassum horneri by High-Speed Countercurrent Chromatography

“…The structural identification of compounds 1-3 was performed by 1 H and 13 C NMR analyses, and the data were compared with literature values. Accordingly, the molecules isolated were identified as saringosterol (1) [14,25,26], phytol (2) [27,28], and fucosterol (3) [14,22,29] (see Supplementary Materials).…”

“…While, as another abundant compounds family present in S. horneri, the development of sterol-related health care products is relatively slow. In fact, studies have shown that phytosterols have a wide range of biological activities and have important properties such as antibacterial, antiviral, antioxidant, and so on [9][10][11][12][13][14]. Recently, fucosterol and saringosterol (see Figure 1) were evaluated for their effects on LXR-mediated transactivation and target gene expression in six cell lines.…”