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Published on: August 31, 2015
Oomicidal activity of polypyrrole nanoparticles against Pythium insidiosum
Lara Baccarin Ianiski1, Aline Fontanella Maciel1, Carla Weiblen2
1Universidade Federal de Santa Maria (UFSM), Santa Maria, RS 97105-900, Brasil.
Abstract:
This study evaluated in-vitro action of a new molecule, the polypyrrole nanoparticles (Ppy-NP), against Pythium insidiosum isolates using M38-A2/CLSI; the minimal inhibitory (MIC) and minimal oomicidal (MOC) concentrations were also determined. Additionally, changes in the hyphae wall of P. insidiosum CBS 575.85 treated with Ppy-NP were evaluated by scanning electron microscopy (SEM). The MIC100 and MOC for all isolates ranged from 8 to 32 μg mL-1, and the MIC90 and MIC50 were 16 μg mL-1. The SEM showed structural damage to the hyphae of P. insidisoum treated with Ppy-NP, as hyphae surfaces with less turgidity were found, thereby showing scaling and ruptures compared to the control (untreated hyphae). Our findings highlighted the anti-P. insidiosum properties of Ppy-NP proved to be a promising candidate for research using pythiosis experimental models.
Insights
Polypyrrole nanoparticles (Ppy-NP) show potent in-vitro activity against Pythium insidiosum, damaging its hyphae. These nanoparticles are a promising candidate for pythiosis research.
Area of Science:
- Mycology
- Nanotechnology
- Antimicrobial Research
Background:
- Pythium insidiosum causes pythiosis, a devastating infection in humans and animals.
- Limited effective treatments are available for pythiosis.
- Novel therapeutic strategies are urgently needed.
Purpose of the Study:
- To evaluate the in-vitro antifungal activity of polypyrrole nanoparticles (Ppy-NP) against Pythium insidiosum.
- To determine the minimal inhibitory concentration (MIC) and minimal oomicidal concentration (MOC) of Ppy-NP.
- To investigate the structural effects of Ppy-NP on P. insidiosum hyphae.
Main Methods:
- In-vitro susceptibility testing of Ppy-NP against P. insidiosum isolates using M38-A2/CLSI guidelines.
- Determination of MIC and MOC values.
- Scanning electron microscopy (SEM) to visualize hyphal morphology changes.
Main Results:
- MIC100 and MOC values ranged from 8 to 32 μg/mL for all isolates.
- MIC90 and MIC50 were consistently 16 μg/mL.
- SEM revealed significant structural damage, including reduced turgidity, scaling, and ruptures in Ppy-NP treated hyphae.
Conclusions:
- Polypyrrole nanoparticles exhibit significant anti-Pythium insidiosum properties in vitro.
- Ppy-NP demonstrate a promising potential for the development of new treatments against pythiosis.
- Further research using experimental pythiosis models is warranted.
