Minireview: algal natural compounds and extracts as antifoulants

Abstract

Marine biofouling is a paramount phenomenon in the marine environment and causes serious problems to maritime industries worldwide. Marine algae are known to produce a wide variety of chemical compounds with antibacterial, antifungal, antialgal, and anti-macrofouling properties, inhibiting the settlement and growth of other marine fouling organisms. Significant investigations and progress have been made in this field in the last two decades and several antifouling extracts and compounds have been isolated from micro- and macroalgae. In this minireview, we have summarized and evaluated antifouling compounds isolated and identified from macroalgae and microalgae between January 2010 and June 2016. Future directions for their commercialization through metabolic engineering and industrial scale up have been discussed. Upon comparing biogeographical regions, investigations from Southeast Asian waters were found to be rather scarce. Thus, we have also discussed the need to conduct more chemical ecology based research in relatively less explored areas with high algal biodiversity like Southeast Asia.

Using chemical language to shape future marine health

“…However, making these compounds durable, easy to use, cost effective in terms of production, and non‐toxic to marine biota is an ongoing challenge (Saha et al . ), and as such the targeted prevention or detachment of marine biofilms via infochemicals has very high economic potential. A process known as “quorum sensing” (QS) often initiates the onset of biofilm formation (Figure b; Figure a) and involves the density‐dependent release of bacterial pheromones (Wirth et al .…”

“…In addition to furanones, seaweeds produce a multitude of chemical compounds with antibacterial, antifungal, antialgal, and antimacrofouling properties (reviewed in Saha et al . ) that dynamically shape the seaweed's biofilm community. The translation of such infochemical research could facilitate the development of novel, natural strategies for suppressing biofilm growth.…”

“…In 2008, the International Maritime Organization introduced a complete ban on the use of TBT-based coatings, and a gradual phasing-out of all metal-containing antifouling agents is expected; these actions have stimulated research into approaches that rely on or are inspired by natural antifouling compounds produced by organisms that are largely free of epibionts. However, making these compounds durable, easy to use, cost effective in terms of production, and non-toxic to marine biota is an ongoing challenge (Saha et al 2017), and as such the targeted prevention or detachment of marine biofilms via infochemicals has very high economic potential. A process known as "quorum sensing" (QS) often initiates the onset of biofilm formation (Figure 1b; Figure 4a) and involves the density-dependent release of bacterial pheromones (Wirth et al 1996), including N-acyl homoserine lactones (AHLs; reviewed in Dobretsov et al [2009]).…”

“…For example, halogenated furanones produced by D pulchra interfere with a universal bacterial QS receptor, thereby disrupting bacterial cell-to-cell communication (Givskov et al 1996;Manefield et al 1999). In addition to furanones, seaweeds produce a multitude of chemical compounds with antibacterial, antifungal, antialgal, and antimacrofouling properties (reviewed in Saha et al [2017]) that dynamically shape the seaweed's biofilm community. The translation of such infochemical research could facilitate the development of novel, natural strategies for suppressing biofilm growth.…”

GC/MS identification and applications of bioactive seaweed extracts from Mediterranean coast of Egypt

“…Marine biofouling is a paramount phenomenon in the marine environment, which leads to serious problems to marine industries worldwide (Saha et al, 2017). The present experiment focused on the antagonistic effect of the encapsulated extracts of C. officinalis and C. sinuosa on biofilm formation.…”