Comparison of UPLC and HPLC for Determination of trans-10-Hydroxy-2-Decenoic Acid Content in Royal Jelly by Ultrasound-Assisted Extraction with Internal Standard

Abstract

The ultra performance liquid chromatography (UPLC) and high performance liquid chromatography (HPLC) method was developed and compared to detect the trans-10-hydroxy-2-decenoic acid (10-HDA) content in royal jelly cream and lyophilized powder. The sample was extracted using absolute ethanol based on the ultrasound-assisted extraction. Chromatographic separation of 10-HDA and methyl 4-hydroxybenzoate as internal standard was carried out on a Nova-pak® C18 column for HPLC and on Acquity BEH C18 column for UPLC. In the HPLC system, the average recoveries were 95.0–99.2% (n = 5) with relative standard deviation (RSD) values of 1.1–2.1% for royal jelly cream and 98.0–100.0% (n = 5) with RSD values of 1.6–3.0% for lyophilized powder, respectively. The limit of detection (LOD) and limit of quantitation (LOQ) were 0.5 and 1.5 mg kg−1 for both royal jelly cream and lyophilized powder. In the UPLC system, the limit of detection (LOD) and limit of quantitation (LOQ) were 0.3 and 1.0 mg kg−1 for both royal jelly cream and lyophilized powder. The major advantages of UPLC, using 1.7 μm particles, over HPLC are the speed of analysis, the narrower peaks and the decrease of solvent consumption for the 10-HDA in the analyses of beeproducts. The two methods were validated for the determination of practical royal jelly products. The concentration of 10-HDA ranges from 1.26 to 2.25% for pure royal jelly cream samples and 3.01–6.26% for royal jelly lyophilized powder samples. For 30 royal jelly products, the 10-HDA content varied from no detectable to 1.005%.