Lipid Classes and Subclasses of Cold-Pressed and Solvent-Extracted Oils from Commercial Indian Niger (Guizotia abyssinica (L.f.) Cass.) Seed.

Lipid classes and subclasses of cold-pressed
and solvent-extracted (hexane and ethanol) oils from
commercially available niger (Guizotia abyssinica (L.f.)
Cass.) seeds were investigated. The oil yield of niger seeds
obtained by cold pressing was 28.3 g/100 g while by
hexane and ethanol extractions was 38.3 and 29.7 g/100 g
respectively. The lipid classification of the extracted niger
seed oils showed neutral lipids (65.9–95.5 %), glycolipids
(2.7–24.6 %) and phospholipids (1.8–9.5 %). The acylglycerol
composition of neutral lipids of extracted niger
seed oils showed triacylglycerols (76.9–91.6 %), diacylglycerols
(3.9–7.3 %) and monoacylglycerols (0.6–2.5 %).
The fatty acid composition of tri-, di-, and monoacylglycerols
of extracted niger seed oils showed linoleic acid
(66.7–71.6 %) as the major fatty acid. The triacylglycerol
composition of neutral lipids of extracted niger seed oils
showed trilinolein (39.2–40.3 %) as the major triacylglycerol.
The extracted niger seed oils contained
1289.9–6215.8 ppm of total phytosterols with b-sitosterol
(41.9–43.7 %) as the major phytosterol. Acylated steryl
glucoside (39.5–52.2 %) was the major glycolipid in
extracted niger seed oils. Phosphatidylcholine (49.6 and
47.9 %) was the major phospholipid in cold-pressed and
hexane-extracted niger seed oils and phosphatidylethanolamine
(57.1 %) was the major phospholipid in ethanolextracted
niger seed oil. This is probably the first report on
the variations in lipid classes and subclasses of Indian niger
seed oil as affected by different modes of oil extraction.