Analysis of beta-sitosterol in seeds and nuts using pressurized liquid extraction and liquid chromatography.
Pressurized liquid extraction (PLE) has been used for the extraction of beta-sitosterol from food samples. In the present work, extractions were performed by mixing ground samples with Hydromatrix celite with methanol at 50 degrees C and 110 bar, using two 5-min cycles. After extraction, beta-sitosterol was analyzed directly by liquid chromatography with diode array detection. The extraction recovery was 92%, with relative standard deviations of 3.7% for intra-day precision and 4.3% for inter-day precision. The presence of beta-sitosterol was confirmed by gas chromatography-mass spectrometry. The proposed method was validated and applied successfully to the determination of free beta-sitosterol in seed and nut samples (almonds, pistachios, peanuts, and sunflower seeds).
Delgado-Zamarreño
M M
MM
Departamento de Química Analítica, Nutrición y Bromatología, Universidad de Salamanca, 37008 Salamanca, Spain. mdz@usal.es
Bustamante-Rangel
M
M
Martínez-Pelarda
D
D
Carabias-Martínez
R
R
D005591:Chemical Fractionation / Q000295:instrumentation / Q000379:methods*; D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D009754:Nuts / Q000737:chemistry*; D011312:Pressure; D015203:Reproducibility of Results; D012639:Seeds / Q000737:chemistry*; D012855:Sitosterols / Q000032:analysis*
D012855:Sitosterols; C025473:gamma-sitosterol