title: Proton NMR for detection, identification and quantification of adulterants in 160 herbal food supplements marketed for weight loss.
abstract: One hundred and sixty food supplements (FS) marketed for weight loss and mainly purchased on the Internet were analyzed. All the FS were claimed as 100% natural containing only natural compounds, plant extracts and/or vitamins and the presence of an active pharmaceutical ingredient (API) was never mentioned. (1)H NMR spectroscopy was used for detecting the presence of adulterants and for their identification and quantification. Mass spectrometry was used as a complementary method for supporting their identification. Among the 164 samples considered because capsules from 5 different blisters of the same FS were analyzed, 56% were tainted with six API. Forty three contained sibutramine as single adulterant (26%), 9 phenolphthalein (6%) and 23 a mixture of these API (14%) that were both withdrawn from the market several years ago because of toxicity concerns. Sildenafil was found in 12 samples, either as a single adulterant (n=5) or in combination with sibutramine (n=3), phenolphthalein (n=3) and both sibutramine and phenolphthalein (n=1). Fluoxetine was present in 4 formulations, alone (n=3) or in combination with sibutramine and orlistat (n=1). At last, lorcaserine was detected in one FS. The content of sibutramine per dosage unit was comprised between 0.1 and 22 mg and that of phenolphthalein between 0.05 and 56 mg. The study also highlights poor manufacturing practices as evidenced for instance by the variability of API in capsules from different blisters of the same box. This paper demonstrates the need for more effective quality control of weight loss FS and the efficiency of (1)H NMR spectroscopy for the detection of tainted FS.
authors.affiliation: Groupe de RMN Biomédicale, Laboratoire SPCMIB (UMR CNRS 5068), Université Paul Sabatier, Université de Toulouse, 118 route de Narbonne, 31062 Toulouse Cedex, France.
authors.forename: Rabab
authors.initials: R
authors.lastname: Hachem
authors.affiliation: Groupe de RMN Biomédicale, Laboratoire SPCMIB (UMR CNRS 5068), Université Paul Sabatier, Université de Toulouse, 118 route de Narbonne, 31062 Toulouse Cedex, France.
authors.forename: Gaëtan
authors.initials: G
authors.lastname: Assemat
authors.affiliation: Service commun de spectrométrie de masse, Université de Toulouse, UPS, 31077 Toulouse Cedex 4, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Martins
authors.affiliation: Groupe de RMN Biomédicale, Laboratoire SPCMIB (UMR CNRS 5068), Université Paul Sabatier, Université de Toulouse, 118 route de Narbonne, 31062 Toulouse Cedex, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Balayssac
authors.affiliation: Groupe de RMN Biomédicale, Laboratoire SPCMIB (UMR CNRS 5068), Université Paul Sabatier, Université de Toulouse, 118 route de Narbonne, 31062 Toulouse Cedex, France.
authors.forename: Véronique
authors.initials: V
authors.lastname: Gilard
authors.affiliation: Groupe de RMN Biomédicale, Laboratoire SPCMIB (UMR CNRS 5068), Université Paul Sabatier, Université de Toulouse, 118 route de Narbonne, 31062 Toulouse Cedex, France.
authors.forename: Robert
authors.initials: R
authors.lastname: Martino
authors.affiliation: Groupe de RMN Biomédicale, Laboratoire SPCMIB (UMR CNRS 5068), Université Paul Sabatier, Université de Toulouse, 118 route de Narbonne, 31062 Toulouse Cedex, France. Electronic address: martino@chimie.ups-tlse.fr.
authors.forename: Myriam
authors.initials: M
authors.lastname: Malet-Martino
mesh_terms: D019587:Dietary Supplements / Q000032:analysis*; D029001:Herbal Medicine; D013058:Mass Spectrometry; D066244:Proton Magnetic Resonance Spectroscopy / Q000379:methods*
keywords: Adulteration; Food supplements; Mass spectrometry; NMR; Weight loss products