Antibacterial and Anti-HIV-1 Reverse Transcriptase Activities of Selected Medicinal Plants and Their Synthesized Zinc Oxide Nanoparticles

Abstract

Human Immunodeficiency Virus infection and Acquired Immune Deficiency Syndrome (HIV/AIDS) and associated opportunistic infections are still global health concerns. Traditional medicines have been used for managing these infections, with little about their biological activities being known. This study evaluated antimicrobial and anti-HIV-1 Reverse Transcriptase (RT) activities of medicinal plants; Harungana madagascariensis, Sapium ellipticum, Pseudospondias microcarpa, Capparis erythrocarpos, and Plectranthus barbatus; and activities of zinc oxide nanoparticles synthesized from aqueous extracts of H.  madagascariensis. Results revealed that aqueous and ethyl acetate extracts of H. madagascariensis, S. ellipticum, P. microcarpa; and ethyl acetate extracts from P. barbatus exhibited minimum inhibitory concentrations ranging from 3.1 to 100 mg mL־¹, while aqueous and ethyl acetate extracts from C. erythrocarpos showed no antibacterial activity. Furthermore, the study revealed that ethyl acetate extracts from P. barbatus, S. ellipticum, C. erythrocarpos and aqueous extract from H. madagascariensis have anti-HIV-1 RT inhibition greater than 50% at 10 mg mL־¹. Aqueous crude extract of H. madagascariensis revealed higher anti-HIV-1-RT (IC₅₀ = 0.9 mg mL־¹) than all other extracts. On the other hand, zinc oxide nanoparticles synthesized from aqueous extract of H. madagascariensis exhibited antibacterial activity greater than all the tested extracts and anti-HIV-1 RT activities comparable to aqueous extract of H. madagascariensis. The results provide scientific information towards drug discovery from medicinal plants.