Abstract
The emergence of HIV strains resistant to the current anti-retroviral drugs has necessitated the search for new anti-retroviral medications. Methanolic and aqueous T. ferdinandiana fruit extracts have potent inhibitory activity against several phases of the HIV-1 replicative cycle. Cell infectivity studies using a non-resistant HIV-1 pseudovirus demonstrated that the methanolic (IC(50) 16 µg/mL) and aqueous extracts (IC(50) 19 µg/mL) were potent inhibitors of viral infection in a non-replicating HIV-1 assay. Both extracts also inhibited HIV-1 reverse transcriptase (IC(50) values of 35 and 33 µg/mL for methanolic and aqueous extracts, respectively) and HIV-1 protease (IC(50) values of 19 and 27 µg/mL, respectively) in recombinant enzyme assays. Given their inhibitory activities against multiple phases of HIV-1 replication, T. ferdinandiana fruit extracts may be particularly useful as HIV-1 therapeutics. Furthermore, both extracts displayed good safety profiles and therapeutic indices, indicating their suitability for therapeutic usage. LC-MS metabolomic profiling analysis of the methanolic extract identified several interesting constituents, including a relative abundance of tannins, as well as several flavonoids and stilbenes. All of these compounds have previously been reported to have bioactivities consistent with the anti-HIV-1 activities reported herein. Based on these studies, methanolic and aqueous T. ferdinandiana fruit extracts are promising potential therapies for the prevention, treatment and management of HIV-1.