Abstract:

The use of natural products as a diet supplement is increasing worldwide but sometimes is not followed by adequate sanitary controls and analyses. Twenty samples of pills and capsules of lyophilised cyanobacteria (blue-green algae), commercialised in Italy as dietary supplements, were found positive at the Vibrio fischeri bioassay. Further analyses with ELISA and LC-MS/MS methods revealed the presence of four microcystin (MC) analogues, MC-LR, -YR, -LA, -RR and two demethylated forms of MC-RR. The highest total microcystin content was 4.5 and 1.4µgg −1 in pills and capsules, respectively. The ELISA measurements, compared to the LC-MS/MS analyses, showed significantly lower concentrations of microcystins in pills, this confirming a possible ELISA underestimate of mixed microcystins, due to different sensitivities for some toxic analogues.

Keywords: Cyanobacteria; Microcystins; Food supplements; ELISA; LC-MS/MS analysis

Document Type: Research article

DOI: 10.1080/14786410500410859

Affiliations: 1: Department of Environment and Primary Prevention, Istituto Superiore di Sanità, V.le Regina Elena 299, 00161, Rome, Italy 2: Department of Food and Animal Safety, Istituto Superiore di Sanità, V.le Regina Elena 299, 00161, Rome, Italy 3: Department of Chemistry, University of Rome “La Sapienza”, P.le Aldo Moro 1, 00161, Rome, Italy