Antimicrobial Activity of Monolaurin Against Borrelia burgdorferi

Abstract

Background: Lyme disease (LD) is a tick-borne infection caused by the spirochete Borrelia burgdorferi (Bb). Bb possesses adaptive mechanisms that enable it to evade retrieval by host immune response. Novel therapeutic modalities to address LD complications are widely being sought. Monolaurin, an ester of glycerol and dodecanoic acid derived from coconut oil, has demonstrated a wide range of antimicrobial activity through emulsification. In this study, we evaluate the antimicrobial activity of monolaurin against the LD spirochete.

Methods: Temperature-shifted Bb cultures were exposed to serial dilutions of monolaurin (4.7 - 300 µg/mL). The resazurin assay and the LIVE/DEAD assay were utilized to assess bacterial viability and establish an approximate minimum inhibitory concentration (MIC).

Results: The MIC value of monolaurin against Bb ranged from 75 to 150 µg/mL. The LIVE/DEAD assay showed a narrower range from 100 to 125 µg/mL. Dead spirochetes increased with rising monolaurin concentrations with statistical significance (P value < 0.0001).

Conclusions: Our findings showed a bactericidal effect of monolaurin against Bb in vitro. Further in vivo studies are required to establish its pharmacodynamics and its combined effects with other antimicrobials for an optimized treatment of LD.

Clin Infect Immun. 2022;7(1):17-21
doi: https://doi.org/10.14740/cii150