Antiviral Activity of Indonesian Medicinal Plants against Hepatitis B Virus

Background: Hepatitis B virus (HBV) infects more than 300 million people globally and is a common cause of liver cancer. Current therapy using reverse transcriptase inhibitors require long-term treatment and the potential risk of development of drug-resistant viruses remains an important issue to be considered. Hence, the development of new drugs is critical. Traditional medicinal plants used for the treatment of infectious diseases may provide a viable option for the discovery of anti-HBV drug candidates. Objective: This study examined anti-HBV activity of 31 kinds of Indonesian plants. Materials and Methods: Crude extracts of various part of plants, leaves and stem, were obtained using dichloromethane and ethanol solvent. The effect on viral entry was examined by determining levels of HBsAg expression in the supernatants of HBV-infected HepG2-NTCP cells by ELISA. The effect on HBV replication was determined by measuring HBV DNAs amounts in Hep38.7-Tet cells by quantitative real-time PCR. Results: The extracts of Phyllantus niruri leaves and Curcuma xanthorrhiza showed reduction of strong HBsAg production from HepG2-NTCP cells with IC₅₀ values of 170.48 and 270.51 μg/mL, respectively. Treatment of HepAD38.7-Tet cells with P. niruri and C. xanthorhiza at the highest concentration while avoiding cytotoxicity reduced extracellular HBV DNA levels by 70% and 30 % of the untreated control respectively. Conclusion: P. niruri inhibited both the entry and HBV replication, thus P. niruri is a promising candidate for anti-HBV drug development.