Content analysis and stability evaluation of selected commercial preparations of St. John's wort

Drug Dev Ind Pharm. 2005 Oct;31(9):907-16. doi: 10.1080/03639040500272066.


Content analysis and stability studies were performed for the commercial products of St. John's wort. Six marketed formulations were analyzed for their hypericin and pseudohypericin content. These products were standardized to contain 0.3% hypericin. Results revealed total hypericin as 7.72-38.57% of the labeled claim with varying concentrations of pseudohypericin. Stability studies were carried out under three different storage conditions: 1) 25+/-2 degrees C, 60+/-5%RH for six months, 2) 40+/-2 degrees C, 75+/-5%RH for six months, and 3) 50 degrees C for one month. Tablet formulations were also analyzed for their hardness and friability. Stability studies revealed significant decrease in the content of the marker compounds with time.

MeSH terms

  • Antidepressive Agents / analysis
  • Capsules
  • Chemistry, Pharmaceutical
  • Chromatography, High Pressure Liquid
  • Drug Stability
  • Environment
  • Hardness
  • Humidity
  • Hypericum / chemistry*
  • Indicators and Reagents
  • Perylene / analogs & derivatives
  • Perylene / analysis
  • Reference Standards
  • Reproducibility of Results
  • Solvents
  • Spectrophotometry, Ultraviolet
  • Tablets
  • Temperature


  • Antidepressive Agents
  • Capsules
  • Indicators and Reagents
  • Solvents
  • Tablets
  • Perylene
  • hypericin
  • pseudohypericin