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Rhamnolipids and Lactonic Sophorolipids: Natural antimicrobial surfactants for oral hygiene

Elshikh, M, Moya-Ramirez, I, Moens, H, Roelants, S, Soetaert, W, Marchant, Roger and Banat, Ibrahim M (2017) Rhamnolipids and Lactonic Sophorolipids: Natural antimicrobial surfactants for oral hygiene. Journal of Applied Microbiology, 123 . [Journal article]

[img] Text - Accepted Version
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DOI: 10.1111/jam.13550


Aims: To assess the efficacy of rhamnolipid (mixture of mono- and di-rhamnolipid congeners, purified monorhamnolipid, dirhamnolipid and lactonic sophorolipid biosurfactants against pathogens important for oral hygiene.Methods and Results: Acquired and produced biosurfactants were fully characterised to allow the antimicrobial activity to be assigned to the biosurfactant congeners. Antimicrobial activity was assessed using the resazurin aided microdilution method. Mixed rhamnolipid JBR425 (MR) and lactonic sophorolipids demonstrated the lowest Minimum Inhibitory Concentration (MIC) which ranged between 100-400 µg ml-1 against Streptococcus mutans, S. oralis, Actinomyces naeslundii, Neisseria mucosa and S. sanguinis. Combining these biosurfactants with standard antimicrobial agents namely Chlorhexidine, Sodium Lauryl Sulphate, Tetracycline HCl and Ciprofloxacin showed a dramatic drop in the MIC values. In addition, in vitro studies demonstrated the biosurfactants’ ability to prevent and disrupt oral pathogens biofilms. The increased permeability of microorganisms treated with biosurfactant, as shown using Bisbenzimide dye, in part explains the inhibition effect.Conclusions: The results demonstrate that rhamnolipids and lactonic sophorolipids have the ability to inhibit oral pathogens both in planktonic and oral biofilm states.Significance and Impact of the Study: The findings indicate the potential value of biosurfactants for both oral hygiene and the pharmaceutical industries since there is a serious need to reduce the reliance on synthetic antimicrobials and antibiotics.

Item Type:Journal article
Keywords:Rhamnolipids, Lactonic sophorolipids, Minimum Inhibitory Concentration, Biofilm, Oral hygiene.
Faculties and Schools:Faculty of Life and Health Sciences > School of Biomedical Sciences
Faculty of Life and Health Sciences
Research Institutes and Groups:Biomedical Sciences Research Institute
Biomedical Sciences Research Institute > Pharmacy & Pharmaceutical Sciences
ID Code:38738
Deposited By: Professor Roger Marchant
Deposited On:02 Oct 2017 15:37
Last Modified:17 Oct 2017 16:31

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