Allicin as a Volatile or Nebulisable Antimycotic for the Treatment of Pulmonary Mycoses: In Vitro Studies Using a Lung Flow Test Rig

Abstract

Fungal infections of the lung are an increasing problem worldwide and the search for novel therapeutic agents is a current challenge due to emerging resistance to current antimycotics. The volatile defence substance allicin is formed naturally by freshly injured garlic plants and exhibits broad antimicrobial potency. Chemically synthesised allicin was active against selected fungi upon direct contact and via the gas phase at comparable concentrations to the pharmaceutically used antimycotic amphotericin B. We investigated the suppression of fungal growth by allicin vapour and aerosols in vitro in a test rig at air flow conditions mimicking the human lung. The effect of allicin via the gas phase was enhanced by ethanol. Our results suggest that allicin is a potential candidate for development for use in antifungal therapy for lung and upper respiratory tract infections.

Combating Black Fungus: Using Allicin as a Potent Antifungal Agent against Mucorales

“…Since the vast majority of fungi so far tested are quite sensitive to allicin [21,23,42], it was expected that zygomycetes would also show allicin sensitivity. However, since this class of fungi has so far not been extensively investigated with respect to allicin sensitivity, a simple drop test was first used to investigate the extent to which the two species tested are sensitive to allicin (Figure 2).…”

“…Treatment of local infections with systemic antifungals can lead to undesirable side effects, which is why treating respiratory tract infections with an antifungally active agent via the gas phase is potentially very promising. Using a lung model, we have already shown with thermotolerant fungi that deposition of allicin-either in the gas phase or as an aerosol-is present in the model and shows efficacy [23]. Subsequently, it will now be necessary to extend the model for the zygomycetes to include the nasopharynx and to conduct analogous experiments.…”

“…Virucidal effects of allicin have also been described [27,28]. Interestingly, allicin is not only active in solution, but also as a vapour [21,23]. This results in a great potential for applications utilizing inhalation, for example in the case of nasal Mucorales infection.…”

“…Subsequently, allicin is formed by spontaneous condensation of two allyl sulfenic acid molecules. As a thiol trapping reagent, it has a broad spectrum of antimicrobial and biocidal functions, for example against phyto-and human-pathogenic bacteria [21,22], including multi drug resistant lung pathogens, as well as fungi [23,24] and parasites [25,26]. Virucidal effects of allicin have also been described [27,28].…”