Antifungal activity of Lactobacillus againstMicrosporum canis,Microsporum gypseumandEpidermophyton floccosum

Abstract

A total of 220 lactic acid bacteria isolates were screened for antifungal activity using Aspergillus fumigatus and Aspergillus niger as the target strains. Four Lactobacillus strains exhibited strong inhibitory activity on agar surfaces. All four were also identified as having strong inhibitory activity against the human pathogenic fungi Microsporum canis, Microsporum gypseum and Epidermophyton floccosum. One of the four lactobacilli, namely Lb. reuteri ee1p exhibited the most inhibition against dermatophytes. Cell-free culture supernatants of Lb. reuteri ee1p and of the non-antifungal Lb. reuteri M13 were freeze-dried and used to access and compare antifungal activity in agar plate assays and microtiter plate assays. Addition of the Lb. reuteri ee1p freeze-dried cell-free supernatant powder into the agar medium at concentrations greater than 2% inhibited all fungal colony growth. Addition of the powder at 5% to liquid cultures caused complete inhibition of fungal growth on the basis of turbidity. Freeze-dried supernatant of the non-antifungal Lb. reuteri M13 at the same concentrations had a much lesser effect. As Lb. reuteri M13 is very similar to the antifungal strain ee1p in terms of growth rate and final pH in liquid culture, and as it has little antifungal activity, it is clear that other antifungal compounds must be specifically produced (or produced at higher levels) by the anti-dermatophyte strain Lb. reuteri ee1p. Reuterin was undetectable in all four antifungal strains. The cell free supernatant of Lb. reuteri ee1p was analyzed by LC-FTMS using an Accela LC coupled to an LTQ Orbitrap XL mass spectrometer. The high mass accuracy spectrum produced by compounds in the Lb. reuteri ee1p strain was compared with both a multianalyte chromatogram and individual spectra of standard anti-fungal compounds, which are known to be produced by lactic acid bacteria. Ten antifungal metabolites were detected.

dl-2-Hydroxyisocaproic Acid Attenuates Inflammatory Responses in a Murine Candida albicans Biofilm Model

“…The efficacy of HICA against a spectrum of planktonically grown bacteria and fungi has been reported (18,19). HICA is an ␣-hydroxy amino acid produced during Lactobacillus fermentation and is also found in human tissues (20,21). It has been used for muscle recovery by professional athletes and for veterinary purposes, such as in animal feed, thus demonstrating its biocompatibility and safety profile (21,22).…”

Effects of Fusarium verticillioides and Lactobacillus Strains Inoculation on Growth and Antioxidant Enzymes Activity of Zea mays Plants

“…Another interesting result of this study was that the antioxidant enzymes activity are decreased in plants that were co-inoculated with F. verticillioides and Lactobacillus strains as compared to plants inoculated with F. verticillioides only. Previously, two characteristics, including antagonistic effects against plant pathogenic fungi (Yan et al 2017;Russo et al 2017;Guo et al 2012) and also high antioxidant activity, ROS scavenging and inhibition of the production of free radicals have been reported for different Lactobacillus species (Virtanen et al 2007;Xing et al 2015).…”

Formulation Development of a Topical Probiotic Gel for Antidermatophytosis Effect

“…In 2012, Guo et al studied the anti-fungal effect of 4 Lactobacillus types against Microsporum canis, Microsporum gypseum and Epidermophyton flocossum by the agar diffusion method. According to their findings, Lactobacillus reutei had the maximum antifungal effect in comparison to the other types (26).…”