HIV-1 reverse transcriptase inhibitor from Phyllanthus niruri

AIDS Res Hum Retroviruses. 1992 Nov;8(11):1937-44. doi: 10.1089/aid.1992.8.1937.


An aqueous extract of Phyllanthus niruri (Euphorbiaceae) inhibited human immunodeficiency virus type-1 reverse transcriptase (HIV-1-RT). The inhibitor against HIV-1-RT in this plant was purified by combination of three column chromatographies, Sephadex LH-20, cellulose, and reverse-phase high-performance liquid chromatography. The inhibitor was then identified by nuclear magnetic resonance (NMR) spectra as repandusinic acid A monosodium salt (RA) which was originally isolated from Mallotus repandus. The 50% inhibitory doses (ID50) of RA on HIV-1-RT and DNA polymerase alpha (from HeLa cells) were 0.05 microM and 0.6 microM, respectively, representing approximately a 10-fold more sensitivity of HIV-1-RT compared with DNA polymerase alpha. RA was shown to be a competitive inhibitor with respect to the template-primer while it was a noncompetitive inhibitor with respect to the substrate. RA as low as 10.1 microM inhibited HIV-1-induced cytopathogenicity in MT-4 cells. In addition, 4.5 microM of RA inhibited HIV-1-induced giant cell formation of SUP-T1 approximately 50%. RA (2.5 microM) inhibited up to 90% of HIV-1 specific p24 antigen production in a Clone H9 cell system.

Publication types

  • Comparative Study

MeSH terms

  • Antigens, Viral / biosynthesis
  • Benzopyrans / isolation & purification
  • Benzopyrans / pharmacology*
  • Binding, Competitive
  • Cell Fusion / drug effects
  • Chromatography
  • DNA-Directed DNA Polymerase / drug effects
  • Dose-Response Relationship, Drug
  • Ellagic Acid / pharmacology
  • Foscarnet / pharmacology
  • Gallic Acid / pharmacology
  • Glucose / analogs & derivatives*
  • Glucose / isolation & purification
  • Glucose / pharmacology
  • HIV Core Protein p24 / biosynthesis
  • HIV Reverse Transcriptase
  • HIV-1 / enzymology*
  • Plant Extracts / pharmacology*
  • Plants / chemistry*
  • Reverse Transcriptase Inhibitors*
  • Zidovudine / pharmacology


  • Antigens, Viral
  • Benzopyrans
  • HIV Core Protein p24
  • Plant Extracts
  • Reverse Transcriptase Inhibitors
  • repandusinic acid A
  • Ellagic Acid
  • Foscarnet
  • Zidovudine
  • Gallic Acid
  • HIV Reverse Transcriptase
  • DNA-Directed DNA Polymerase
  • Glucose