The use of stable isotope ratio analysis to characterise saw palmetto (Serenoa Repens) extract

Saw palmetto extract (SPE) has many pharmacological effects. Thus, its demand and value has increased steadily, along with the presence of counterfeit SPEs on the market. In this work bulk delta C-13, delta H-2, delta O-18 and fatty acid delta C-13, delta H-2 analysis was performed in 20 authentic and 9 commercial SPEs, 12 meat fats and 4 pure fatty acids. Authentic SPEs are characterised by bulk values from -31.0 parts per thousand to -29.7 parts per thousand for delta C-13, -176 parts per thousand to -165 parts per thousand for delta H-2, 27.2 parts per thousand to 40.7 parts per thousand for delta O-18, and values of capric, caprylic, lauric, myristic, palmitic and oleic acids from -37.4 parts per thousand to -30.5 parts per thousand for delta C-13 and -187 parts per thousand to -136 parts per thousand for delta H-2. The isotopic values of all the commercial SPEs were out of these ranges and more similar to those of meat fat and pure fatty acids. Stable isotope ratio analysis can therefore be proposed as a suitable tool for detecting adulteration in SPEs.