Investigations of the phytochemical content of Sceletium tortuosum following the preparation of “Kougoed” by fermentation of plant material

Aim of the studySceletium plant species that contain alkaloids are claimed to have mood elevation and anti-anxiety properties, especially after the plant material has been fermented. The fermented preparation is locally known as “kougoed” or “channa” and has been emphasized and advertised for its increased potency when incorporated in commercial products. The aim of the study was to investigate quantitative and qualitative changes in alkaloidal content following fermentation of plant samples carried out under controlled conditions and also on pure mesembrine hydrochloride (MHCl).Materials and methodsSamples were prepared from the aerial parts of Sceletium tortuosum. Studies were also conducted on mesembrine hydrochloride (MHCl) in aqueous and methanolic solutions under similar conditions of exposure to sunlight as well as under ambient and elevated temperature (40 ± 2 °C). Quantitative and qualitative changes in alkaloidal content were monitored by HPLC and LC–MS, respectively.Results and ConclusionsThe initial fermentation study showed transformation of mesembrine to Δ7mesembrenone, where the content of the former decreased from a concentration of 1.33% to 0.05% whilst the latter increased from below its limit of quantitation (LoQ) to 0.11% on the 10th day. The experiments on pure MHCl revealed similar transformations in aqueous solutions whereas no change was seen in methanolic solutions. Sunlight and aqueous conditions appear necessary to facilitate the transformation, which was confirmed by the absence of such a transformation when solutions of MHCl were kept in the dark.