Effect of chemical modifications of tannins on their antimicrobial and antibiofilm effect against Gram-negative and Gram-positive bacteria

Abstract

BackgroundTannins have demonstrated antibacterial and antibiofilm activity, but there are still unknown aspects on how the chemical properties of tannins affect their biological properties. We are interested in understanding how to modulate the antibiofilm activity of tannins and in delineating the relationship between chemical determinants and antibiofilm activity.Materials and methodsThe effect of five different naturally acquired tannins and their chemical derivatives on biofilm formation and planktonic growth of Salmonella Typhimurium, Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus was determined in the Calgary biofilm device.ResultsMost of the unmodified tannins exhibited specific antibiofilm activity against the assayed bacteria. The chemical modifications were found to alter the antibiofilm activity level and spectrum of the tannins. A positive charge introduced by derivatization with higher amounts of ammonium groups shifted the anti-biofilm spectrum toward Gram-negative bacteria, and derivatization with lower amounts of ammonium groups and acidifying derivatization shifted the spectrum toward Gram-positive bacteria. Furthermore, the quantity of phenolic OH-groups per molecule was found to have a weak impact on the anti-biofilm activity of the tannins.ConclusionWe were able to modulate the antibiofilm activity of several tannins by specific chemical modifications, providing a first approach for fine tuning of their activity and antibacterial spectrum.

Decreasing Microbial Contamination in Culture Water of Siamese Fighting Fish (<i>Betta splendens</i>) Using Cinnamon Extract

“…Other active ingredients in cinnamon are tannins (polyphenolic compounds commonly found in most herbs) that have antibacterial properties. Villanueva et al [29] reported that tannic acid could inhibit the growth of bacteria in fish intestines by binding iron and forming a chelate that is toxic to the membranes of microorganisms. When tannins form a chelating complex with iron in the medium, this action ceases the availability of iron for microorganisms to grow under aerobic conditions.…”

“…Cinnamaldehyde has been reported to inhibit Siamese fighting fish pathogens, including Vibrio cholerae, Vibrio parahaemolyticus [23], Aeromonas hydrophila [4,8,9,24,25], Pseudomonas sp. [4,9,23,29], Edwardsiella sp. [9,23], Plesiomonas shigelloides [9], Enterobacter sp.…”

“…[9,10], and Staphylococcus sp. [9,23,29]. One study revealed cinnamaldehyde could act as an antibacterial by increasing cell surface hydrophobicity, reducing bacterial aggregation, and inhibiting acid production and acid tolerance [26].…”

Comparison of the Antibacterial Effectiveness of Moringa Leaf Extract (Moringa oleifera) on the Growth of Enterococcus faecalis and Streptococcus mutans Bacteria in Vitro

“…According to Isyraqi et al (2020), the mechanism of saponin as an antibacterial is by reducing the surface tension of bacterial cell walls which causes cell permeability to increase, so that intracellular compounds will come out. Tannins have antibacterial action by causing damage to the permeability of bacterial cell walls, microsomes and lysosomes as a result of the interaction of flavonoids with bacterial DNA so that they can dissolve extracellular protein complexes (Villanueva et al, 2023).…”

Plant‐derived virulence arresting drugs as novel antimicrobial agents: Discovery, perspective, and challenges in clinical use

“…Condensed tannins are composed of polymers of flavan‐3‐ols. Tannins have potential pharmacological properties, such as antibacterial, antiinflammatory, and antitumor effects (Villanueva et al, 2022; Wang et al, 2023). Tannic acid is a typical representative of hydrolyzable tannins, which significantly inhibited the expression of T3SS effector proteins in Salmonella enterica serovar Typhimurium ( S. Typhimurium ) by down‐regulating the transcription levels of two key regulatory and structural genes, sipA and sipB .…”