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Trials to develop environmentally friendly marine paints based on natural materials as replacement for copper and tin compounds for fouling and marine corrosion control.

Green algae, tubeworms in dead powder form and garlic were used as natural anti‐fouling components in the paints developed. Electrochemical technique was employed for testing the potential of both tubeworms and garlic in terms of inhibition of steel corrosion in seawater. Marine paint formulations containing each of the three selected natural materials were applied onto PVC and un‐primed steel surface, which were immersed in natural seawater for the assessment of their anti‐fouling and anti‐corrosion properties. The results of visual assessment and seawater analysis were also used for such an evaluation.

Tubeworms act as mixed type inhibitor while garlic affects the potential cathodic process of steel in seawater. Tubeworms‐based paint, with 25 per cent in the dry paint film, could protect steel surface from marine corrosion up to 7 months. The paints containing algae and garlic, and the corresponding algae/garlic free paints, resisted slime film formation. Steel and PVC coated surfaces with paint containing algae showed the best anti‐fouling potential within the prepared series.

The investigation only involved the application of the dead form of green algae and tubeworms as effective pigments in the developed paints. It is recommended that further research should focus on extracting and identifying the active components in each organism against fouling and marine corrosion.

The paint formulations developed (containing 25 per cent by weight tubeworms in the paint film) could be used to protect un‐primed steel surface against fouling and marine corrosion for a reasonably long duration.

The application of one paint formulation on un‐primed steel surface for its protection from both fouling and marine corrosion is novel. The electrochemical studies of steel in natural seawater in presence of tubeworms and garlic are original.

Current evidence indicates that humans and animals are at increased risk of multiple health challenges due to microplastic (MP) profusion. However, mitigation is constrained by inadequate scientific data, further aggravated by the lack of evidence in many African countries. This review therefore synthesized evidence on the current extent of MP pollution in Africa and the analytical techniques for reporting.

A literature search was undertaken in research databases. Medical subject headings (MeSH) terms and keywords were used in the literature search. The authors found 38 studies from 10 countries that met the inclusion criteria.

Marine organisms had MPs prevalence ranging from 19% to 100%, whereas sediments and water samples had between 77 and 100%. The most common and dominant polymers included polypropylene and polyethylene.

This review shows that most studies still use methods that are prone to human errors. Therefore, the concentration of MPs is likely underestimated, even though the authors’ prevalence evaluations show MPs are still largely pervasive across multiple environmental matrices. Also, the study reveals significant spatial disparity in MP research across the African continent, showing the need for further research in other African countries.

Even though some reviews have assessed MPs pollution in Africa, they have not evaluated sample prevalence, which is necessary to understand not only concentration but pervasiveness across the continent. Secondly, this study delves deeper into various methods of sampling, extraction and analysis of MPs, as well as limitations and relevant recommendations.

The purpose of this paper was to identify Serratia marcescens to extract and purify prodigiosin pigment to evaluate the antibacterial potential of the pigment.

Samples were collected from shrimp aquaculture ponds. Species identification was conducted using morphological, biochemical and molecular tests. Pigment extraction and purification were carried out using column chromatography. The antibacterial effect of crude and purified prodigiosin pigment was evaluated on Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus as biofouling bacteria. In addition, the interaction between prodigiosin and proteins involved in biofilm formation was evaluated using molecular docking.

The results of prodigiosin extraction with solvents showed the highest percentage of pigment presence with methanol solvent in the second day of culture. The chemical structure of pure prodigiosin obtained from the column chromatography was confirmed by Fourier-transform infrared spectroscopy. Both crude and purified pigments exhibited antibacterial effects against selected bacterial strains. The antibacterial effect of the purified pigment was higher, and the highest antibacterial effect was observed on B. subtilis. Prodigiosin docking was carried out with all target proteins, and the docked energy in all of them was at an acceptable level.

Prodigiosin extracted from S. marcescens can be used as a bioactive compound to design and manufacture of anti-biofouling and anti-biofilm formation products to use extensively for industrial applications as a natural color in marine industries, food industry, cosmetics and textile productions.

The marine organisms, Tube worms, Bryozoa, Enteromerpha and Ulva Spp, have been tested to be used as antifouling agents. Each organism was incorporated as effective ingredient in two different marine paint formulations in presence of other complementary pigments. The coatings were applied on different substrates and the panels immersed in Alexandria western harbour. The environmental condition of the harbour water has been also mentioned. The antifouling durability of the coatings were followed through the calculation of the wet weight of fouling organisms accumulated on the coated panels and the control one. The result showed that the antifouling activity of the organisms depend on the paint formulation and the substrate.

The purpose of this paper is to study the interaction of main marine organisms on localized corrosion of 316L stainless steel in the Dalian Sea area.

The steel plate was immersed in the Dalian Sea area for nine months to observe the biofouling and localized corrosion. The local potential distribution on the steel plate covered by marine organisms was measured. The local electrochemical measurements were performed to facilitate understanding the interfacial status under different biofouling conditions. The local surface morphologies and corrosion products were characterized.

The localized corrosion of stainless steel is mainly induced by the attachment of barnacles on the steel. The mussels have no influence on the localized corrosion. The cover of sea squirts could mitigate the localized corrosion induced by barnacles. Both crevice corrosion and pitting corrosion were found beneath the barnacle without the covering of sea squirts. The pitting damage was more serious than the crevice corrosion in the Dalian Sea area. The probing of sulfur element indicates that the potential growth of sulfate-reducing bacteria at barnacle center.

The above findings revealed that the interaction of marine organisms has significant influences on the localized corrosion of stainless steel. The influences of macro-fouling and micro-fouling on localized corrosion are discussed.

In case any of you are expecting a tale of mystery and intrigue on the high seas—complete with ships in hidden coves—I'm afraid I must disappoint you. My Drugs from the Sea story is not so dramatic, although it has its excitement (since the potential is always there for discovering a miracle drug from life in the sea).

The purpose of this paper is to develop protective coatings containing antifouling compound for steel rebars.

In the present study, corrosion and settlement of micro and macro‐fouling organisms on coated and uncoated rebars were investigated. Two different types of coatings were applied: only primer for prevention of corrosion; and rosin‐based antifouling paint after application of primer.

According to results, the surfaces of the rebars coated by antifouling paints were remarkably cleaner than were those of uncoated and primer‐coated steels. Micro and macro‐organisms that settled on the rebars were identified after 90 days of seawater immersion in Izmir, Turkey.

The paper contributes to scientific literature by providing a protection method based on the use of antifouling coatings for steel rebars used in marine environments (e.g. bridge piers). It was concluded that steel rebars can be coated with antifouling paints before they are used for concrete constructions.

The purpose of this paper is to study the correlation between different topographies and the reaction of Ulva Linza fouling species.

In this research, topographies with a different method, such as hot embossing and hot pulling, were achieved, and biological analyses were done with macroalgae Ulva Linza cells. The effect of topography via local binding geometry (honeycomb size gradients) and Wenzel roughness on the settling of Ulva microorganisms was tested.

As a result, Ulva spores confirmed different reactions to a similar set of tapered microstructures that was in agreement with the results on distinct honeycombs. The local binding geometry and the Wenzel roughness factor “r” were dominant on settling of Ulva Linza spores.

The reaction of an organism at the interface of vehicles’ substrate is powerfully affected by surface topographies.

The best embedment occurred on structures with bigger sizes than Ulva Linza’s spores. The density of settled spores was proportional to Wenzel roughness and the spores favour to attach to “kink sites” positions.

Unfortunately, unpleasant aggregation of marine biofouling on marine vehicles’ surfaces, generate terrific difficulties in the relevant industry.

There was a sharp relationship between Wenzel roughness and settle of Ulva Linza spores. The local binding geometry and the Wenzel roughness factor “r” were dominant on settling of Ulva Linza spores.

The term microbiologically induced corrosion (MIC) appears to be very closely related to the composition of the bio‐film which harbours the micro‐organism. Formation of an initial slimy layer on immersed metallic substrates is the rate‐controlling parameter of bio‐fouling, as uninterrupted undesirable growth of bio‐films occurs over this layer. To contain this bio‐film problem, formation of an adherent layer of toxic and inhibited corrosion product, that interacts with biofilm, could be exploited. Deals with the preliminary interactions of a few copper‐based alloys, with mildly toxic alkaloid class‐inhibitive compounds, in a simulated marine environment. It is assumed that the toxic and inhibited corrosion product and bio‐film interaction layer will interfere with the formation of the initial slimy cover on the immersed surface, responsible for bio‐fouling. It is seen that these alkaloid compounds exert a limited response on the inhibition of copper‐based alloys like monel. Brucine appears to be a more effective inhibitor for the monel surface. Pre‐oxidation of the uninhibited brass surface and also post‐oxidation of the inhibited surface appear to consolidate the corrosion product bio‐film‐inhibitor interaction layers, indicating the compatibility of these alkaloid compounds to the probable thermal strains to be encountered in engineering services. This indicates the possibility of using these compounds in heat transfer devices, like heat exchangers, where seawater is used as coolant.

Where do you go to find information and data on marine pollution? This paper sets out to give pointers to the most useful sources, and is divided into three sections: bibliographic sources, data sources and referral sources.