Plant extracts as natural amoebicidal agents

Area of Science:

• Pharmacology
• Microbiology
• Botany

Background:

• Acanthamoeba sp. infections cause severe diseases like granulomatous encephalitis, keratitis, and pneumonia.
• Current treatments for acanthamoebiasis are often ineffective and have high mortality rates.

Purpose of the Study:

• To evaluate the amoebicidal and amoebistatic potential of plant extracts from Rubus chamaemorus, Pueraria lobata, Solidago virgaurea, and Solidago graminifolia.
• To assess the therapeutic efficacy and safety of these plant extracts against Acanthamoeba infections.

Main Methods:

• Plant materials (aboveground parts, flowers, roots, leaves) were extracted.
• In vitro assays were performed to determine amoebicidal/amoebistatic activity and effective concentrations.
• In vivo studies were conducted using Acanthamoeba-infected animal models to evaluate survival rates and toxicity.

Main Results:

• Extracts from S. virgaurea, P. lobata, and R. chamaemorus exhibited significant in vitro activity at low concentrations (0.01-0.05 mg/mL).
• Therapeutic indices ranged from 3.5 to 20, indicating a favorable safety profile.
• In vivo experiments showed a 2.5-3 fold increase in survival time for animals treated with the plant extracts.

Conclusions:

• Plant extracts from R. chamaemorus, P. lobata, and S. virgaurea possess valuable chemotherapeutic properties against Acanthamoeba.
• These natural extracts demonstrate potential for both topical and systemic use in managing acanthamoebiasis.
• The tested extracts were found to be non-toxic in animal models, supporting their potential therapeutic application.