In vitro Evaluation the Efficacy of Some Nnew Plant Extracts and Biocides on the Viability of Acanthamoeba castellanii

The purpose of this study was to assess the efficacy of certain plant extracts and to compare them with current biocides on the viability of Acanthamoeba castellanii cysts and trophozoites in vitro. Amoebicidal and cysticidal assays were performed against both trophozoites and cysts of Acan-thamoeba castellanii (ATCC 50370). Ten plant extracts were evaluated alongside the current agents included polyhexamethylene biguanide (PHMB), octenidine and chlorhexidine digluconate. A. castel-lanii (ATCC 50370) was treated to serial two-fold dilutions of the test compounds and extracts in micro -titre plate wells to investigate the effect on trophozoites and cysts of A. castellanii (ATCC 50370). Furthermore, the toxicity of each of the test compounds and extracts were assessed towards a mam-malian cell line. Minimum trophozoite inhibitory concentration (MTIC), minimum trophozoite amoebi-cidal concentration (MTAC), and minimum cysticidal concentration (MCC) were used to establish A. castellanii (ATCC 50370) in vitro sensitivity. The findings of this research revealed that the biguanides PHMB, chlorhexidine, and octenidine all had excellent effectiveness against trophozoites and cysts of A. castellanii (ATCC 50370). The plant extracts testing results showed that, great activity against trophozoites and cysts of A. castellanii (ATCC 50370) at lower concentrations. This is the first study to demonstrate that the Proskia plant extract had the lowest MCC value, which was 3.9 lg/mL. The time kill experiment confirmed this finding, as this extract reduced cysts of A. castellanii (ATCC 50370) by more than 3-log at 6 hour and by 4-log after 24 hour. The anti-amoebic efficacy of new plant extracts on the viability of A. castellanii (ATCC 50370) cysts and trophozoites was comparable to existing biocide treatments and was not toxic when tested on a mammalian cell line. This could be a promising novel Acanthamoeba treatment by using the tested plant extracts as a monotherapy against trophozoites and cysts.Crown Copyright (c) 2023 Published by Elsevier GmbH. All rights reserved.

Automated summary

The study aimed to evaluate the efficacy of certain plant extracts and compare them with current biocides on the viability of Acanthamoeba castellanii cysts and trophozoites in vitro. The results showed that the biguanides PHMB, chlorhexidine, and octenidine had excellent effectiveness against A. castellanii trophozoites and cysts. The plant extracts also showed significant activity against A. castellanii at lower concentrations, with Proskia plant extract having the lowest cysticidal concentration value.