Antiviral Extract Preparation and Characterization

Guava leaf, green tea leaf, and rose petal extracts were purchased from Daejong Biotech Co., Ltd. (Seoul, Korea). We then prepared BEN815 by mixing these extracts in a 65:30:5 ratio, respectively. The active compounds were quercetin, EGCG, ellagic acid, gallic acid, kaempferol, and myricetin, the content and efficacy of which were analyzed in a previous study [15 (link)]. The mixture was dissolved in 0.9% saline and stored at -20°C. Nirmatrelvir was obtained from MedChemExpress (Monmouth Junction, NJ, USA); a stock solution was prepared by dissolving Nirmatrelvir in 0.9% saline containing 1% dimethyl sulfoxide and 20% sulfobutylether-β-cyclodextrin (MedChemExpress), which was stored at -20°C.