Dengue virus (DENV) is a member of the Flaviviridae family and is responsible for the most common mosquito-borne human disease. Currently, there are no available antiviral drugs to treat DENV infections. However, certain flavonoids, including baicalein and baicalin, have demon-strated significant anti-DENV effects in vitro. This study aimed to assess the bioavailability of baicalein and its metabolite, baicalin, in the blood serum of Albino Wistar rats using the LC/MS/MS method. The in vitro activity of sera obtained from rats administered baicalein was evaluated for its anti-DENV properties using quantitative RT-PCR and the Foci Forming Reduction Assay (FFRA). The results obtained through LC/MS/MS analysis indicated that the bioavailability of baicalin in rat blood serum reached 44.20 µg/ml one hour after oral administration of baicalein. Furthermore, the sera collected from rats given baicalein exhibited a significant 78.26% inhibition of DENV-2 replication when tested against Dengue-2 using both quantitative RT-PCR and FFRA. These findings suggest that baicalein and baicalin hold promise as potential therapeutic candidates for further investigation in the development of treatments against DENV infections.

Dengue has long been a serious health burden to the global community, especially for those living in the tropics. In spite of the availability of vaccines, effective treatment for the infection is still needed and currently remained absent. In the present study, antiviral properties of the KSF 103 ME which consisted of a number of potential antiviral compounds were investigated against DENV-2. The effects of this extract against DENV-2 replication were determined using the qRT-PCR. Findings from the study suggested that the KSF 103 ME showed maximum inhibitory properties toward the virus during the virus entry stage at concentrations of more than 12.5 µg/mL. Minimal antiviral activities were observed at other virus replication stages; adsorption (42% reduction at 50 µg/mL), post-adsorption (67.6% reduction at 50 µg/mL), prophylactic treatment (68.4% and 87.7% reductions at 50 µg/mL and 25 µg/mL, respectively) and direct virucidal assay (48% and 56.8% reductions at 50 µg/mL and 25 µg/mL, respectively. The KSF 103 ME inhibited dengue virus repication with an IC50 value of 20.3 µg/mL and SI value of 38.9. The KSF 103 ME showed potent antiviral properties against DENV during the entry stage. Further studies will be needed to deduce the antiviral mechanisms of the KSF 103 ME against DENV.