The legume plant Griffonia simplicifolia Baill. (Caesalpiniaceae) is a perennial woody shrub which grows in the tropical rain forest of West and Central Africa, with sites of cultivation present in Ghana, Ivory Coast, and Togo. The seed chemical constituents are characterized by the presence of 5-hydroxy-L-tryptophan (5-HTP).

5-HTP is a direct precursor and enhancer of the activity of the brain hormone serotonin (5-hydroxytryptamine, 5-HT). After entering the central nervous system, 5-HTP is converted to 5-HT by the enzyme tryptophan decarboxylase.

G. simplicifolia seed extracts have been used as a valid natural product to alleviate insomnia, migraine, headache, appetite, and to support mood, memory, and many other functions.

The UV absorption spectra of 5-HTP, tryptamine, tryptophan, and 5-hydroxytryptamine are very similar, with strong absorption between 230 and 300 nm, which makes UV spectrophotometric assay of 5-HTP in seed material almost impossible. Therefore, Biosfered uses HPLC methods coupled to mass spectrometry for the identification and quantification of G. simplicifolia natural constituents.

Nostrexin® is a G. simplicifolia extracts that contains a standardized amount (30%) of 5-HTP along with the presence of characteristic alkaloids, including, among others, hyrtioerectine B, griffonine and hyrtiosulawesine. Nostrexin® shows an alkaloid:5-HTP ratio lower than 1:10, which grants the genuineness of the product and the absence of fermentation by products.