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

Abstract

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.

Keywords: Adulteration; GC-IRMS; Meat fats; Pure fatty acids; Saw palmetto (Serenoa Repens) extract (SPE).