Phytosterols in supplements containing Serenoa repens: an example of variability of active principles in commercial plant based products.

Phytosterols are one of the bioactive components responsible for the beneficial effects of Serenoa repens in Benign Prostate Hyperplasia. The aim of this study was to verify the actual variability of the phytosterols content in supplements containing serenoa, in order to provide useful elements to check the effectiveness of these preparations. The amount of campesterol, stigmasterol and ß-sitosterol were determined by gas-chromatography in commercial raw materials and supplements containing serenoa in association or not with other botanicals. The experimental data were used to calculate amounts of phytosterols for recommended daily dose. The overall results of this study show an extreme variability in the content and also in the amounts per daily dose of phytosterols of the examined supplements (both mono/multi components). These data confirm that the characterization of serenoa based supplements is insufficient to ensure comparable effects between different products.

Polyphenols, dietary sources and bioavailability.

Fruit and beverages such as tea and red wine represent the main sources of polyphenols. Despite their wide distribution, the healthy effects of dietary polyphenols have come to the attention of nutritionists only in the last years. The main factor responsible for the delayed research on polyphenols is the variety and the complexity of their chemical structure. Emerging findings suggest a large number of potential mechanisms of action of polyphenols in preventing disease, which may be independent of their conventional antioxidant activities. To establish evidence for the effects of polyphenol consumption on human health and to better identify which polyphenols provide the greatest effectiveness in disease prevention, it is first of all essential to determine the nature and the distribution of these compounds in our diet, and secondly to better know their bioavailability.

Convenient TLC for the detection of a herbal ingredient in a food supplement.

This study describes a practical and suitable approach to solve a real problem: the analysis of polyherbal products for which some specifications addressing the composition are lacking (e.g. chemical components). It is reported that an analytical procedure to verify the possible presence in a botanical supplement of a plant is not authorised for use in Italy. No reference of chemical standards for the known components of the plant is commercially available. For this reason and because a rapid response was required, more selective chromatographic techniques such as high-performance liquid chromatography, gas chromatography and liquid chromatography-mass spectrometry were excluded and thin layer chromatography was chosen for applying different experimental procedures. The original English label of the product, which is made by a leading US manufacturer and sold online by American and Italian distributors, lists the same herbal ingredients as the Italian label, but with an addition of Eurycoma longifolia Jack, which is not included in the list of plants admitted in supplements compiled by the Italian Ministry of Health. For greater certainty of the result, a high-performance thin layer chromatography method was then applied. On the basis of the results obtained, it was possible to confirm that E. longifolia Jack was not present in the product.