Investigation on the toxic potential of Tribulus terrestris in vitro

Pharm Biol. 2015 Apr;53(4):469-76. doi: 10.3109/13880209.2014.924019. Epub 2014 Dec 4.


Context: Tribulus terrestris L. (Zygophyllaceae) has been commonly used to energize, vitalize, and improve sexual function and physical performance in men.

Objective: This study investigates the potential cytotoxic and genotoxic, and endocrine disrupting activities of T. terrestris in vitro.

Materials and methods: The whole T. terrestris plant was extracted with water, methanol, and chloroform. The genotoxic potential of T. terrestris extracts at 3-2400 µg/mL was assessed by Comet assay in a rat kidney cell line (NRK-52E) and by Ames assay in Salmonella typhimurium TA98 and TA100 strains. Endocrine disrupting effects of the extracts at concentrations of 0.22-25 000 µg/mL were assessed by YES/YAS assay in Saccharomyces cerevisiae. Cytotoxic activity of the extracts was determined by the MTT test in NRK-52E cells. The different exposure times were used for four tests (3-48 h).

Results: The methanol extract of T. terrestris IC50 value was 160 µg/mL. The other extracts did not show cytotoxic effects. In the Comet and Ames genotoxicity assays, none of the extracts possessed genotoxic activities at concentrations of 0-2400 µg/mL. Only the water extract of T. terrestris induced frame shift mutations after metabolic activation. The water extract also showed estrogenic activity by YES/YAS assay in S. cerevisiae at concentrations ≥27 µg/mL (≥2.6-fold), while the other T. terrestris extracts had anti-estrogenic properties.

Conclusion: Tribulus terrestris had estrogenic and genotoxic activities. The study was useful in determining its toxicological effects and the precautions regarding consumption.

Keywords: Cytotoxicity; endocrine disturbing; genotoxicity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Culture Techniques
  • Cell Line
  • Cell Survival / drug effects
  • Comet Assay
  • DNA Damage*
  • Dose-Response Relationship, Drug
  • Endocrine Disruptors / isolation & purification
  • Endocrine Disruptors / toxicity*
  • Estrogen Receptor alpha / genetics
  • Estrogen Receptor alpha / metabolism
  • Humans
  • Mutagens / isolation & purification
  • Mutagens / toxicity*
  • Plant Extracts / isolation & purification
  • Plant Extracts / toxicity*
  • Rats
  • Receptors, Androgen / genetics
  • Receptors, Androgen / metabolism
  • Saccharomyces cerevisiae / drug effects
  • Salmonella typhimurium / drug effects
  • Salmonella typhimurium / genetics
  • Transfection
  • Tribulus / chemistry
  • Tribulus / toxicity*


  • Endocrine Disruptors
  • Estrogen Receptor alpha
  • Mutagens
  • Plant Extracts
  • Receptors, Androgen