Extraction and Analysis of Fresh Ginger Root and Ginger Dietary Supplement

Traditional Hawaiian and ayurvedic medicine uses ginger root to relieve infl ammation. The active ingredient(s) in ginger that decrease infl ammation are not known and thus any processing of the fresh product into a dietary supplement risks losing the crucial compound(s). This project compared the chemical composition of raw ginger to processed root in the form of a selected commercially available dietary supplement capsule. A reverse-phased high-pressure liquid chromatography method was developed to separate three gingerols (6, 8 and 10) and 6-shogaol, four of the active compounds in ginger. Standards of these components were used to identify and quantify the compounds in the various ginger extracts. To obtain the extracts, fidifferent solvents (water, methanol, dichloromethane, hexane, and a 80:20 methanol-water mixture) were used. Repetitive dilutions were used to determine the extraction effi ciency and ensure complete extraction using the different solvents. The amount of the four analyzed compounds in each extract varied depending on the solvent used, but in each case they represented only a small percentage of the extract, and an even smaller percentage of the entire sample. Amongst the analyzed components 6-shogaol was found almost exclusively in the extracts of the dietary supplement ginger sample. This fact is most likely due to the oxidation of 6-gingerol into 6-shogaol during manufacturing and storage. The extracts were also analyzed by liquid chromatography/mass spectrometry (LC/MS) to identify other components present in the extracts.