In vitro amoebicidal activity of ethanol extracts of Arachis hypogaea L., Curcuma longa L. and Pancratium maritimum L. on Acanthamoeba castellanii cysts

Abstract

Acanthamoeba castellanii causes amoebic keratitis which is a painful sight-threatening disease of the eyes. Its eradication is difficult because the amoebas encyst making it highly resistant to anti-amoebic drugs, but several medicinal plants have proven to be more effective than the usual therapy. This study aimed to evaluate the in vitro amoebicidal activity of ethanol extracts of Arachis hypogaea L. (peanut), Curcuma longa L. (turmeric), and Pancratium maritimum L. (sea daffodil) on A. castellanii cysts. Acanthamoeba were isolated from keratitic patients, cultivated on 1.5% non-nutrient agar, and then incubated with different concentrations of plant extracts which were further evaluated for their cysticidal activity. The results showed that all extracts had significant inhibitory effect on the multiplication of Acanthamoeba cysts as compared to the drug control (chlorhexidine) and non-treated control, and the inhibition was time and dose dependent. The ethanol extract of A. hypogaea had a remarkable cysticidal effect with minimal inhibitory concentration (MIC) of 100 mg/ml in all incubation periods, while the concentrations of 10 and 1 mg/ml were able to completely inhibit growth after 48 and 72 h, respectively. The concentrations 0.1 and 0.01 mg/ml failed to completely inhibit the cyst growth, but showed growth reduction by 64.4-82.6% in all incubation periods. C. longa had a MIC of 1 g and 100 mg/ml after 48 and 72 h, respectively, while the concentrations 10, 1, and 0.1 mg/ml caused growth reduction by 60-90.3% in all incubation periods. P. maritimum had a MIC of 200 mg/ml after 72 h, while the 20-, 2-, 0.2-, and 0.02-mg/ml concentrations showed growth reduction by 34-94.3% in all incubation periods. All extracts seemed to be more effective than chlorhexidine which caused only growth reduction by 55.3-80.2% in all incubation periods and failed to completely inhibit the cyst growth. In conclusion, ethanol extracts of A. hypogaea, C. longa, and P. maritimum could be considered a new natural agent against the Acanthamoeba cyst.

Amoebicidal activity of phytosynthesized silver nanoparticles and theirin vitrocytotoxicity to human cells

“…Besides this, AgNPs synthesized from J. gossypifolia were able to prevent encystment of the trophozoites. In addition, many plant metabolites such as flavonoids and alkaloids are reported for their antiparasitic potential although the mechanism of action is not yet clear (El-Sayed et al, 2012). Currently available drugs are known to cause unwanted effects on the plasma membrane of ocular cells (Ehlers & Hjortdal, 2004) thus this combination of nanoparticles and plant metabolites may give rise to a broad spectrum of drugs that can be used in the treatment of Acanthamoba infection.…”

Amebicidal effects of fenugreek (Trigonella foenum‐graecum) against Acanthamoeba cysts

“…They stated that cysts were more resistant to this suppressive effect (Karakuş, Malatyalı, Zengin, & Değerli, ). Again, the minimal inhibitory concentrations (MIC) of Arachishypogaea L. , Curcuma longa L., and Pancratium maritimum L., A. hypogaea of 100 mg/ml were checked at 24, 48, and 72 hr and C. longa was effective at 1 mg/ml in 48 hr, while P. maritimum was effective at 200 mg/ml in 72 hr (El‐Sayed, Ismail, Ahmed, & Hetta, ).…”

In Vitro Testing of Potential Entamoeba histolytica Pyruvate Phosphate Dikinase Inhibitors

“…It is an essential metabolite that has therapeutic benefits and can be found in Pancratium maritimum L. This compound and other similar alkaloids also exhibit antimalarial, antiviral, antineoplastic, and antiparasitic (against Encephalitozoon intestinalis) activity. 37,38 In addition, pancratistatin that was extracted and purified from the Pancratium littorale inhibited E. intestinalis infection without affecting host cells. 39 Another study conducted by El-Sayed et al 38 found pancratistatin to be responsible for the cysticidal activity of P. maritimum against Achantamoeba castellani.…”

“…37,38 In addition, pancratistatin that was extracted and purified from the Pancratium littorale inhibited E. intestinalis infection without affecting host cells. 39 Another study conducted by El-Sayed et al 38 found pancratistatin to be responsible for the cysticidal activity of P. maritimum against Achantamoeba castellani. Pancratistatin at very low concentrations (< 1 mM) also induced apoptosis, specifically in a broad range of cancer cell lines.…”