Screening of potential antiviral activity of seven Philippine medicinal plants

Abstract

Seven of the ten Philippine medicinal plants as stated by the Department of Health Philippines: Cassia alata, Momordica charantia, Allium sativum, Psidium guajava, Peperomia pellucida, Blumea balsamifera, and Mentha cordifola Opiz ex Fresen were screened for their potential antiviral activity. Antiviral tests were carried out through two main methodologies: a viral plaque assay using dengue virus and Reverse Transcription Polymerase Chain Reaction (RT-PCR) through addition of the plant extracts to the reverse transcriptase of the Moloney Murine Leukemia Virus (MoMLV). The viral plaque assay was unsuccessful due to the possible death of cells before the incorporation of the second overlay with the dye, leading to no formation and visualization of plaques. For the RT-PCR assay, inhibitory activity was detected from Mentha cordifolia and Blumea balsamifera, showing slight inhibition of formation of bands at 50 ug/mL and 100 ug/mL, respectively. Strong inhibitory activity was detected from Psidium guajava, demonstrating slight inhibition of bands at 10 ug/mL and complete inhibition at 50 ug/mL. Prevention of the formation of bands after PCR is indicative of inhibition of cDNA synthesis, a process governed by the reverse transcriptase enzyme This inhibition suggests that the said extracts have an inhibitory activity against the reverse transcriptase, and could potentially be tested further as antiretrovirals.