Trilinolein, also known as glyceryl trilinoleate, is a polyunsaturated triacylglycerol (TAG) composed of three linoleic acid (C18:2 cis-9,12) chains esterified to a glycerol backbone. Abundant in safflower, sunflower, and corn oils (~60–70% in high-linoleate varieties), this highly fluid lipid contrasts saturated tristearin and monounsaturated triolein by maximizing membrane disorder and oxidative susceptibility in the TAG series.
Chemical Structure
Trilinolein has the molecular formula C57H98O6 and a molecular weight of 879.4 g/mol. Each linoleoyl chain bears two cis double bonds at Δ9,12 positions, yielding a compact yet kinked geometry with conical packing (logP 17.4), prone to peroxidation and lipase hydrolysis releasing essential omega-6 fatty acids.
Physical Properties
A pale yellow, low-viscosity liquid (melting point −5 to −4°C, density 0.925 g/mL at 20°C, boiling point ~816°C predicted), trilinolein exhibits extreme hydrophobicity (log10WS −19.5) and solubility in chloroform/ethanol but immiscibility in water. Its ΔfusH ~149 kJ/mol and high ΔvapH (169 kJ/mol) reflect fluid chains preventing crystallization.
Biological Functions
Hydrolyzed to linoleic acid—essential for prostaglandin synthesis, skin barrier integrity, and arachidonic acid precursors—trilinolein fuels β-oxidation while supporting eicosanoid signaling. Excess levels correlate with oxidative stress and inflammation in metabolic disorders.
