Antimicrobials from Seaweeds for Food Applications

Abstract

The exponential growth of emerging multidrug-resistant microorganisms, including foodborne pathogens affecting the shelf-life and quality of foods, has recently increased the needs of the food industry to search for novel, natural and eco-friendly antimicrobial agents. Macroalgae are a bio-diverse group distributed worldwide, known to produce multiple compounds of diverse chemical nature, different to those produced by terrestrial plants. These novel compounds have shown promising health benefits when incorporated into foods, including antimicrobial properties. This review aims to provide an overview of the general methods and novel compounds with antimicrobial properties recently isolated and characterized from macroalgae, emphasizing the molecular pathways of their antimicrobial mechanisms of action. The current scientific evidence on the use of macroalgae or macroalgal extracts to increase the shelf-life of foods and prevent the development of foodborne pathogens in real food products and their influence on the sensory attributes of multiple foods (i.e., meat, dairy, beverages, fish and bakery products) will also be discussed, together with the main challenges and future trends of the use of marine natural products as antimicrobials.

Exploring Dose-Dependent Cytotoxicity Profile of Gracilaria edulis-Mediated Green Synthesized Silver Nanoparticles against MDA-MB-231 Breast Carcinoma

“…A broad spectrum of natural compounds have been identified in green, red, and brown algae that have a variety of bioactive properties, including antimicrobial, antioxidant, antiviral, anti-inflammatory, cytotoxic, antimitotic, antineoplastic, and antifouling activity [ 22 ]. Extracts from marine algae also have the potential to synthesize inorganic metallic nanoparticles [ 23 , 24 ].…”

Algal Phlorotannins as Novel Antibacterial Agents with Reference to the Antioxidant Modulation: Current Advances and Future Directions

“…They resemble tannins from terrestrial plants and are thought to play a role in cell wall formation. Phlorotannins are made by polymerizing phloroglucinol (1,3,5-trihydroxybenzene) monomer units in a range of combinations, similarly to the well-studied biosynthesis of terrestrial plant tannins from alcoholic monomers [52][53][54]. However, the biochemical mechanism for phlorotannin biosynthesis is poorly understood, with several hypotheses ranging from acetate and malonate unit condensation to the shikimate or phenylpropanoid pathways.…”

“…PTs are the most effective agents for fighting bacterial biofilms because they penetrate the bacterial cell wall by changing the shape of the cell membrane and causing cell death [87,88]. Bacterial cell wall permeability is damaged by PTs, which cause proton leakage in the cell membrane, thus structural changes in the nuclear membrane leading to bacterial cell death [53,89,90]. In addition, PTs have the ability to eradicate bacteria by inhibiting their reproduction.…”

Seaweed Extracts: A Promising Source of Antibiofilm Agents with Distinct Mechanisms of Action against Pseudomonas aeruginosa

“…The green (Ulva lactuca "Sea lettuce"), the brown (Stypocaulon scoparium "Sea broom"), and the red (Pterocladiella capillacea) algae were chosen for their wide range of demonstrated bioactivities [12,14,20]. The originality of this study lies in the fact that algae are scarcely explored for their potential antibiofilm activity [21][22][23][24]. After preparation of different extracts, their antibiofilm activity was evaluated using two complementary assays: the crystal violet staining method and the quantification of adhered living cells by the colony-forming unit (CFU) counting method Both effects on the initial adhesion and biofilm progression and on 24-h-old biofilms were evaluated.…”