Evaluation of in Vitro Antiviral Activity of Centaurea Kotschyi var. Decumbens Extracts Against Herpes Simplex Virus Type 1 (HSV-1)

Abstract

Centaurea kotschyi var. decumbens, some kind of the species in Centaurea L. (Asteraceae) genus have been used for the treatment to the herpes infection around children’s lips in Turkish folk medicine, is an endemic species in Turkey. The methanol and aqueous extracts of this plant were tested as in vitro anti-HSV-1 activity to obtain new antiviral agents using natural sources. The colorimetric XTT test was used to assess the maximum non-toxic concentration of the extracts and evaluation of their antiherpetic activity in the experiments. 50% cytotoxic concentrations of the extract (CC₅₀) and the concentration of 50% protection (EC₅₀) against to the cytopathic effect caused by the virus were calculated with nonlinear regression statistical analysis by using the program of GraphPad Prism's. After 72 h incubation in Vero cells, CC₅₀ values were determined as 504.30 µg/mL for methanol extract and 880.90 µg/mL for aqueous extract. Methanol extract of C. kotschyi var. decumbens showed a moderate antiviral activity with 3.63 selective index (SI= the ratio of CC₅₀ to EC₅₀), while aqueous extract showed a weak antiherpetic activity with 1.25 SI value.

Keywords: Centaurea kotschyi var. decumbens, Methanolic and aqueous extracts, Herpes simplex virus type 1, Antiviral activity