RT Journal Article
SR Electronic
T1 Structural characterization of a case-implicated contaminant, "Peak X," in commercial preparations of 5-hydroxytryptophan.
JF The Journal of Rheumatology
JO J Rheumatol
FD The Journal of Rheumatology
SP 89
OP 95
VO 30
IS 1
A1 Klaus Klarskov
A1 Kenneth L Johnson
A1 Linda M Benson
A1 Jennifer D Cragun
A1 Gerald J Gleich
A1 Monika Wrona
A1 Xiang-Rong Jiang
A1 Glenn Dryhurst
A1 Stephen Naylor
YR 2003
UL http://www.jrheum.org/content/30/1/89.abstract
AB OBJECTIVE: To determine the chemical structure of a contaminant, X1, previously found in eosinophilia myalgia syndrome case-implicated 5-hydroxytryptophan (5-OHTrp), and also present in over-the-counter (OTC) commercially available 5-OHTrp. METHODS: Case-implicated 5-OHTrp as well as 6 OTC samples were subjected to accurate mass HPLC-mass spectrometry and HPLC-electrochemical detection, and reacted with reduced glutathione. Peak X1 was subsequently subjected to HPLC-tandem mass spectrometry (MS/MS), as well as the resulting nucleophilic glutathione product. All these data were compared with analysis carried out under identical conditions on authentic 4,5-tryptophan-dione (Trp-4,5D). RESULTS: Based on accurate mass, tandem mass spectrometric analysis, and comparision with authentic standard compound analysis, X1 was determined to be 4,5-tryptophan-dione, a putative neurotoxin. The presence of X1 in OTC samples varied from 0.5 to 10.3% of the amount of Trp-4,5D present in case-implicated 5-OHTrp. CONCLUSION: Peak X1 was identified as the putative neurotoxin Trp-4,5D. It was found in case-implicated 5-OHTrp as well as 6 OTC samples. This gives some cause for concern in terms of the safety of such commercial preparations of 5-OHTrp.