Lipid composition of Silybum marianum cell cultures treated with methyl jasmonate

Abstract

Elicitation of cell cultures of Silybum marianum with methyl jasmonate (MeJA) increases the production and release of the secondary metabolite silymarin into the culture medium and this process seems to be dependent on phospholipase D activity and its product phosphatidic acid (PA). However, MeJA did not alter total membrane lipid content or overall fatty acid composition. A progressive increase in some galactolipids was observed with elicitation time. Phospholipids were mainly represented by phosphatidylcholine (PC) followed by phosphatidylethanolamine (PE) and phosphatidylinositol (PI). MeJA caused losses of PC species that contain two unsaturated acyl species, 36:5 and 36:6 and an increase in 36:2 species. A drop in the ratio of compounds with 18:3 in PI and PE was also observed. The presence of the lysophospholipids (LP) LPC (16:0, 18:3, 18:2, 18:1) and LPE (16:0, 18:3, 18:2, 18:1) and the high contents of PA, represented by the molecular species 34:3, 34:2 and 36:5 and 36:4, indicates high basal level of phospholipase activity in cultures and a high phospholipid turnover. MeJA treatment did not quantitatively alter these lipid classes.

Keywords

• galactolipids
• lipid signalling
• lysophospholipids
• phospholipids
• secondary metabolites
• silymarin