Antiviral effect of natural plant extracts against alphaherpesvirus infections

CAROLA FERRECCIO; MAIDANA S. S; ROCIO TAU; SALVAT ADRIANA; KONIGHEIM BRENDA; ROMERA S.A.

Congreso; 18th Ecology and Evolution of Infectious Diseases (online) meeting; 2021

The caprine herpesvirus type 1 (CpHV-1) is distributed throughout the world where there isproduction of goats, in Argentina it was reported in different regions with seroprevalencesbetween 27% and 43%. It causes systemic and genital disease (abortions). There is no specifictreatment, although the application of Acyclovir interfere with viral replication with differentdegrees of efficacy has been reported. Due to the costs and side effects produce, thesearch for new chemotherapeutic agents is essential. This is how the objective of the workarises, which is to evaluate the in vitro effectiveness of native plant extracts as antiviraltreatment. Larrea divaricata (Jarilla, family Zygophyllaceae), Mintostachys verticilata (orpeppermint, family Lamiaceae) and Parastrephia lepidophylla (or tola, family Asteraceae) incomparison with Aciclovir effect were evaluated. The in vitro characterization of the antiviraleffect of the extracts was evaluated by assays of maximum non-cytotoxic concentration,cytotoxic concentration 50, inhibitory concentration 50, lysis plaques and viral replicationkinetics on MBDK cells. Jarilla, peppermint and Tola are not cytotoxic at a concentration of1.04 mg/ml. The Tola extracts obtained in different years (T1 and T2) presented the highestvalues of cytotoxicity, CC50= 0.57 mg/ml and 0.9 mg/ml respectively; peppermint extractpresented CC50= 1.6 mg/ml. Jarilla extract was the best tolerated, presenting CC50= 2.4mg/ml. Peppermint and Tola 2 presented the best antiviral activity with IC50= 0.16 mg/ml,Jarilla an IC50= 0.26 mg/ml and Tola 1 with IC50= 0.32 mg/ml. The average plaque lysis ofpeppermint and Tola was similar (177,170) and Jarilla (21,174). Jarilla's selectivity Indiax(CC50/IC50) was 9.2, peppermint 10, Tola 1 1.78, Tola 2 5.6. In Jarilla's kinetics, a viral titer of 5was obtained in the extracellular fraction at 24 h and 475 in the intracellular. The extractsshow antiviral activity which offers possibilities of finding active compounds against CpHV-1.