A historical source page presents an English-language article titled Comparative Analytical Investigation of Tribulus Terrestris Preparations. It attributes the work to D. Obreshkova, T. Pangarova, S. Milkov and D. Dinchev and identifies publication in Pharmacia, volume XLV, book 2/1998, p. 11.
What the historical comparison examined
The source compares raw materials and finished preparations by analytical profile. It discusses furostanol saponins and identifies compounds including protodioscin and protogracillin.
Selected figures from the historical source
The full historical page lists multiple raw-material lots and finished products. The selected entries below illustrate the format of the earlier comparison. This is not a current market survey.
| Historical source entry | Principal furostanol saponins listed | Historical figure reported |
|---|---|---|
| Sopharma Tribestan raw-material lot 01196 | Protodioscin, protogracillin | 51.6% |
| Sopharma Tribestan raw-material lot 20297 | Protodioscin, protogracillin | 57.0% |
| Dabur, India VI-1006 raw material | Unknown | 0.1% |
| TSI raw material, lot SM971016 | Protogracillin | 20.0% |
Why the historical comparison matters
The article documents the earlier position that products labelled “Tribulus” should not automatically be treated as analytically equivalent. Origin, raw material, extract specification and finished-product profile can matter.
What it does not prove today
The comparison is historical. Products, suppliers, formulations, manufacturing processes and analytical methods may have changed. It should not be used as a blanket statement about every product currently sold.