Phenolic Compounds in Bacterial Inactivation: A Perspective from Brazil

Abstract

Phenolic compounds are natural substances that are produced through the secondary metabolism of plants, fungi, and bacteria, in addition to being produced by chemical synthesis. These compounds have anti-inflammatory, antioxidant, and antimicrobial properties, among others. In this way, Brazil represents one of the most promising countries regarding phenolic compounds since it has a heterogeneous flora, with the presence of six distinct biomes (Cerrado, Amazon, Atlantic Forest, Caatinga, Pantanal, and Pampa). Recently, several studies have pointed to an era of antimicrobial resistance due to the unrestricted and large-scale use of antibiotics, which led to the emergence of some survival mechanisms of bacteria to these compounds. Therefore, the use of natural substances with antimicrobial action can help combat these resistant pathogens and represent a natural alternative that may be useful in animal nutrition for direct application in food and can be used in human nutrition to promote health. Therefore, this study aimed to (i) evaluate the phenolic compounds with antimicrobial properties isolated from plants present in Brazil, (ii) discuss the compounds across different classes (flavonoids, xanthones, coumarins, phenolic acids, and others), and (iii) address the structure–activity relationship of phenolic compounds that lead to antimicrobial action.

Exposing Salmonella Senftenberg and Escherichia coli Strains Isolated from Poultry Farms to Formaldehyde and Lingonberry Extract at Low Concentrations

“…Flavonols (quercetin derivatives), phenolic acids (derivatives of caffeoylquinic, caffeoyl-hexose-hydroxyphenol, and coumaroyl-hexose-hydroxyphenol acids), procyanidins (A and B dimmers), and iridoids were the most dominant compounds extracted from V. vitis-idaea. It is confirmed in the literature [48][49][50] that these substances exhibit antiadhesive and antibiofilm activities. The adhesion process is a very important step in the biofilm formation process.…”

“…The interaction of bioactive compounds with cell adhesion receptors can explain this phenomenon [52]. The antibiofilm activity of phenolics can also be connected with the rupture of the bacterium's cytoplasmic membrane, reduction in membrane fluidity, and binding to bacterial DNA, leading to the inhibition of nucleic acids synthesis, cell wall synthesis, or energy metabolism [49,51]. Phenolic compounds are also known to be nonspecific inhibitors of autoinducer-mediated cell-cell signaling in bacteria.…”

“…Interestingly, the strongest antimicrobial effect was obtained against Gram-negative Pseudomonas spp. [49]. Kryvtsova et al [24] showed that the leaf extract of V. vitis-idaea more effectively inhibited the process of biofilm formation by S. aureus strains than berry extract did.…”

Effects of Dietary Tuber Ethanolic Extract of Nut Grass (Cyperus rotundus Linn.) on Growth, Immune Response, and Disease Resistance in Nile Tilapia (Oreochromis niloticus)

“…Phenolic compounds, recognized as natural substances synthesized through secondary metabolites [84,85], play a crucial role in this context. Phenolic compounds possess diverse biological activities, including anti-inflammatory, antioxidant, and antimicrobial properties [86]. Notably, plant flavonoids exhibit antimicrobial effects, particularly targeting Gram-positive bacteria.…”

The Chemical Space of Marine Antibacterials: Diphenyl Ethers, Benzophenones, Xanthones, and Anthraquinones

“…Bearing in mind the structural similarity between these marine polyketides and terrestrial or synthetic polyketides, it is reasonable to assume that they could share similar modes of action. Natural and synthetic polyketides bearing the four studied scaffolds have been shown to act on efflux pumps [ 46 ], bacterial cell membranes [ 46 , 47 ], DNA gyrase B [ 48 ], and transpeptidases [ 49 ] and through reactive oxygen species [ 50 ]. As the studied MPs can show different mechanisms of action, we focused our study on the de facto expressed antibacterial activity.…”