Abstract
Red vine leaf extracts (RVLEs) have traditionally been used for leg wellness and are now standardized to be used as over-the-counter (OTC) drugs in Europe. In Japan, one brand of RVLE products was recently approved as a direct OTC drug, and RVLEs are still used as ingredients in health food products. Since there is no mandated criterion for the quality of health food products in Japan, the consistent quality and composition of these products are not assured. Here we analyzed OTC drug and health food products containing RVLEs with different lot numbers by LC/MS. Subsequent multivariate analyses clearly indicated that the quality of the health food products was highly variable compared to that of the drug products. Surprisingly, the component contents in the health foods were different even within a same lot in a same brand. The quantitative analyses of flavonols and stilbene derivatives in the drugs and health foods indicated that the concentration of each substance was kept constant in the drugs but not in the health foods. These results strongly indicated that the quality of RVLEs as a whole was not properly controlled in the manufacturing process of health foods. Since RVLE is an active ingredient with pharmaceutical evidences and is used for drugs, the proper regulation for ensuring the consist quality of RVLEs from product to product would be recommended even in the health foods.
