Polyphenols from brown seaweeds as a potential antimicrobial agent in animal feeds

Ford, Lauren; Stratakos, Alexandros Ch.; Theodoridou, Katerina; Dick, Jaimie T.A.; Sheldrake, Gary N.; Linton, Mark; Corcionivoschi, Nicolae; Walsh, Pamela J.

Abstract

Seaweeds offer a natural source of antimicrobials that may help curb antibiotic resistance in livestock. The antibacterial activity of phlorotannin extracts isolated from two brown seaweeds Ascophyllum nodosum and Fucus serratus was tested. The mechanism of action of phlorotannin extracts against Escherichia coli O157, Salmonella agona, and Streptococcus suis was elucidated by observing cell membrane permeability and intracellular adenosine triphosphate (ATP). The two extracts were effective at killing three foodborne pathogens without negatively affecting the pig intestinal cells. A. nodosum minimum inhibitory concentration (MIC) range for the different pathogens was between 1.56 and 0.78 mg/mL, whereas F. serratus was 3.13 mg/mL for all pathogens tested. A. nodosum was found to be much more potent compared to F. serratus. The difference in potency in the seaweeds may be a result of the phlorotannins' structural linkages. The antimicrobial properties of the seaweed extracts tested may provide alternative and complementary treatments to antibiotics and zinc oxide in animal feeds. The seasonal screening was performed on both species to assess the availability of phenolics throughout the year using two quantification methods, the Folin-Ciocalteu (FC) assay and quantitative nuclear magnetic resonance (NMR). The variation between the methods highlights the challenges involved in the quantification of complex phenolic structures. However, both methods show that the phenolics are subject to seasonal variation, which may prove problematic to the animal feed industry.

Citation

Ford, L., Stratakos, A. C., Theodoridou, K., Dick, J. T., Sheldrake, G. N., Linton, M., …Walsh, P. J. (2020). Polyphenols from brown seaweeds as a potential antimicrobial agent in animal feeds. ACS Omega, 5(16), 9093-9103. https://doi.org/10.1021/acsomega.9b03687

• Journal Article Type: Article
• Acceptance Date: Mar 30, 2020
• Online Publication Date: Apr 10, 2020
• Publication Date: Apr 28, 2020
• Deposit Date: Jun 25, 2021
• Journal: ACS Omega
• Electronic ISSN: 2470-1343
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 5
• Issue: 16
• Pages: 9093-9103
• DOI: https://doi.org/10.1021/acsomega.9b03687
• Public URL: https://uwe-repository.worktribe.com/output/7450732