Investigating the antibacterial and anti-biofilm activity of agave syrup as a traditional wound remedy

The global threat posed by antibiotic resistant infections highlights the urgent need to identify novel antimicrobials. In recent years, there has been a growing interest in revisiting and evaluating historical infection remedies for their antimicrobial activity. The Agave plant held significant social, religious, and medicinal value to the Mexica (commonly referred to as the Aztecs), as well as other Indigenous Mesoamerican communities. The use of Agave syrup mixed with salt was traditionally used in wound care as documented in the Florentine Codex, a sixteenth-century text authored by Spanish Franciscan friar Bernardino de Sahagun. The minimum inhibitory concentration was determined through the microbroth dilution method, whilst anti-biofilm activity was measured using crystal violet staining. In this current study, we demonstrated that commercially available Agave syrups primarily derived from the Agave tequilana species significantly inhibit the growth of Gram-positive and Gram-negative wound-associated pathogens in planktonic culture. The traditional practice of adding salt enhanced the efficacy against Escherichia coli. Furthermore, Agave syrups significantly inhibited biofilm formation across all six organisms tested, although their capacity to disrupt pre-formed biofilms appears to be species specific. Preliminary investigations into the underlying antibacterial mechanisms of Agave syrups suggest that it is likely due to a combination of factors, including their acidic pH, along with the presence of saponins, methylglyoxal, and the generation of hydrogen peroxide. This study contributes to the growing evidence that historical remedies like Agave syrup may be effective as new antimicrobial treatments.