Study on the Inhibitory Effect of Wood Vinegar from Vitis vinifera and Casuarina equisetifolia on HSV-1

Herpes simplex virus type 1 (HSV-1) infection is one of the most common oral diseases, clinically presenting as gingivostomatitis and cold sores. Current treatments primarily rely on nucleoside antiviral drugs, which often suffer from low bioavailability and a tendency to induce drug resistance. Therefore, preventing HSV-1 infection and developing new antiviral agents are of great importance. Wood vinegar, a liquid obtained from the pyrolysis and condensation of wood such as tree branches, plant stems, or fruit trees, has been reported to possess various biological activities, including antiviral and anti-inflammatory effects. This study aims to investigate the cytotoxicity, anti-HSV-1 activity, and chemical composition of two types of wood vinegar derived from Vitis vinifera and Casuarina equisetifolia using the CCK-8 assay, cytopathic effect (CPE) analysis, and gas chromatography–mass spectrometry (GC-MS). Results showed that both wood vinegars exhibited certain toxicity toward Vero and L929 cells, but no toxicity was observed in Vero cells at a 64-fold dilution. In vitro antiviral experiments demonstrated that both preparations possessed good anti-HSV-1 activity, though their preventive effects against HSV-1 infection require further investigation. GC-MS analysis revealed that the main chemical components of the two wood vinegars were acids, aldehydes, and phenolic compounds, with higher levels of trans,trans-2,4-Heptadienal, N,N-Dimethylaniline, and sorbic acid, among others. In summary, this study provides a new theoretical foundation and research direction for the potential application of wood vinegar in the prevention and treatment of herpes simplex virus infections.