Investigation of the Purity of Ursolic Acid Dietary Supplements

Aims: Ursolic acid (UA) is a phytochemical found in fruits and herbs such as apples, cherries, rosemary and thyme. A multitude of rodent studies have shown UA’s protective effects in cancer, cardiovascular disease, diabetes, obesity, and neurodegenerative diseases. This study aims to investigate if a high purity UA dietary supplement is available for use in future human studies.

Place and Duration of Study: Theoretical weight studies were performed at the University of Texas at San Antonio while UA quantification studies were performed in the Metabolomics Laboratory at The University of Texas Health Science Center at San Antonio between January 2015 and July 2015.

Methodology: Four oral UA supplements were analyzed for percent theoretical weight and UA concentration. UA supplement content was analyzed by high performance liquid chromatography–electrospray ionization mass spectrometry (HPLC-ESI-MS) and the UA concentration was calculated based on a standard curve. Additional high abundance compounds were identified using HPLC-ESI-MS.

Results: All UA supplement capsules averaged over 200% theoretical weight. The UA concentration in the supplements ranged from 14-49% and 12 additional compounds were identified.

Conclusion: UA supplements provided more than 200% the stated quantity listed on the Supplement Facts Panel. However, UA supplements contained less than 50% UA and additional compounds identified were constituents of plants or commonly found in food products. A UA supplement with higher purity is needed to investigate its therapeutic effects in humans.