Characterisation of the phospholipid fraction of hulled and naked tetraploid and hexaploid wheats

Phospholipid (PL) profile was determined on lipids extracted from the whole grains of 10 genotypes of tetraploid wheats (Triticum dicoccon Schrank and Triticum durum Desf.) and 10 genotypes of hexaploid wheats (Triticum spelta L. and Triticum aestivum L.) by a liquid chromatography system coupled on-line with an evaporative light scattering detector (HPLC-ELSD). Phosphatidylethanolamine, phosphatidylinositol and phosphatidylcholine were the major PL determined, accounting for more than 70% of total PL. PL represented about 10% of total lipids and were detected in naked wheats at levels of 10.1 and 10.4 g/100 g of lipids (T. durum and T. aestivum, respectively) whereas in the corresponding ancestors T. dicoccon and T. spelta PL amounts were 8.4 and 9.1 g/100 g of lipids, respectively. PL amount in naked wheats was about 17% higher than that determined on average in hulled wheats: 10.2 ± 2.8 vs. 8.7 ± 2.2 g/100 g of lipids, respectively. A hyphenated system HPLC-ELSC was revealed as a useful and more informative tool to identify different PL classes with a minimal experimental workout in comparison to the organic phosphorus assay. The identification of PL molecular species was performed by HPLC, employing as detector a mass spectrometer working in negative ASI-ES mode.