Gullapalli, Kowmudi; Karthika, Anoop; Nagappan, Krishnaveni; Naveen, Shivanna; Hernández-Ledesma, Blanca.
Journal of Food Measurement and Characterization, on line.
https://doi.org/10.1007/s11694-023-02008-1
Resumen
Lunasin is a cancer-preventive food bioactive peptide. This study reports quantifcation of lunasin from selected varieties of soybeans, wheat grains and their commercial products. Lunasin was extracted using a simple extraction protocol that combined liquid–liquid extraction with deionized water and n-heptane and solid-phase extraction with C18 stationary phase. The ultra-performance liquid chromatographic (UPLC) separation of lunasin was achieved on an C18 column (50 mm×2.1 mm, 1.7 µm) using 0.1% aqueous formic acid (A) and 0.1% formic acid in acetonitrile (B) as mobile phase components delivered in a gradient mode for 10 min at a fow rate of 0.4 mL min−1. Electrospray ionisation (ESI) in positive polarity resulted in improved analyte ionisation, and detection was accomplished with a quadrupole
time-of-fight mass spectrometer (Q-ToF/MS). Analyte quantifcation was carried out using ion chromatograms extracted at m/z 838.8. The UPLC-ESI-Q-ToF/MS was validated using matrix-matched standard reference materials.
The method was found to be linear (17 to 10,200 ng mL−1), sensitive, accurate (mean recovery values greater than 91.1%), precise (relative standard deviations less than 2.40%). The extraction and quantifcation process were found to be efcient (88.1%-93.0%) and was used to quantify lunasin (mg/g sample) from soybeans (12.3–10.9), wheat (0.29–0.19), and their commercial products (0.00–5.56). A selective, specifc, and reliable liquid chromatography-mass spectrometric method of quantifying lunasin from complex food matrices was developed and validated, allowing for sensitive quantitation as well as a wider concentration range of quantifcation, making it a viable candidate for regular laboratory assay of lunasin from soybean and wheat-based food products.
