Investigation of the antifouling constituents from the brown alga Sargassum muticum (Yendo) Fensholt

Abstract

One of the most promising alternatives to toxic heavy metal-based paints is offered by the development of antifouling coatings in which the active ingredients are compounds naturally occurring in marine organisms and operating as natural antisettlement agents. Sessile marine macroalgae are remarkably free from settlement by fouling organisms. They produce a wide variety of chemically active metabolites in their surroundings, potentially as an aid to protect themselves against other settling organisms. In this study, a dichloromethane extract from the brown seaweed Sargassum muticum was tested in situ and, after 2 months of immersion, showed less fouling organisms on paints in which the extract was included, compared to paints containing only copper after 2 months of immersion. No barnacles or mussels have been observed on the test rack. Identification by NMR and GC/MS of the effective compound revealed the abundance of palmitic acid, a commonly found fatty acid. Pure palmitic acid showed antibacterial activity at 44 µg mL −1, and also inhibited the growth of the diatom Cylindrotheca closterium at low concentration (EC 50 =45.5 µg mL −1 ), and the germination of Ulva lactuca spores at 3 µg mL −1 . No cytotoxicity was highlighted, which is promising in the aim of the development of an environmentally friendly antifouling paint.

<i>In vitro</i> antimicrobial screening of <i>Lycoperdon lividium</i> and determination of the ethanol extract composition by gas chromatography/mass spectrometry

“…It is mainly used to produce soaps and cosmetics. Hexadecanoic acid is also proposed as an antimicrobial agent in several researches (Glover et al, 1997;Risk et al, 1997;Bazes et al, 2009). Hexadecanoic acid also presented a significant antibacterial activity against S. mutans (Huang et al, 2011).…”

Novel Antibacterial Proteins from the Microbial Communities Associated with the Sponge Cymbastela concentrica and the Green Alga Ulva australis

“…Free fatty acids with antimicrobial properties have also been identified from algae and sponges (3,9,29,31), and it is possible that the role of the hydrolases detected from the sponge-and alga-associated microbial communities is the conversion of lipids excreted by the eukaryotic host to free fatty acids with antibacterial properties. This in turn may prevent the colonization or growth of certain bacteria and hence may have an impact on the community composition of the host's microbiota.…”

Glycoglycerolipids Isolated from Marine DerivedStreptomyces coelescensPK206-15

“…Palmitic acid, isolated from the brown alga Sargussum muticum, and 2-hydroxymyristic acid and (9Z)-oleic acid, derived from the marine bacterium Shewanella oneidensis, inhibit spores of U. pertusa. 39,40) In the present experiment, the antifouling activity of commercial free fatty acids was determined. It showed less activity than the glycoglycerolipids, suggesting that glycolycerolipids are responsible for the antifouling activity, not the fatty acids alone.…”