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 δ13C, δ2H, δ18O and fatty acid δ13C, δ2H 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‰ to −29.7‰ for δ13C, −176‰ to −165‰ for δ2H, 27.2‰ to 40.7‰ for δ18O, and values of capric, caprylic, lauric, myristic, palmitic and oleic acids from −37.4‰ to −30.5‰ for δ13C and −187‰ to −136‰ for δ2H. 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