83
(mainly containing C14/C16 saturated FAs and C18/C16 unsaturated FA moieties)
in Sargassum horneri (Turner) C. Agardh using RPLC-MS/MS, with MGDGs containing 18:2 at sn-2 position showing reduced triglycerides and FA accumulation in
adipocytes. HILIC-ESI/IT-TOF-MS was used to analyze partial lipidomic profiles
of a few seaweeds including Pterocladiella capillacea (S. G. Gmelin) Santelices &
Hommersand containing lipid classes, viz., PG, PC, PI, LPI, PS, LPE, DGDG,
SQDG, and SQMG, Asparagopsis taxiformis (Delile) Trevisan had a single SGMG,
and Dictyota dichotoma (Hudson) J. V. Lamouroux mainly contained glycerophospholipids PC, LPE, SQMG, and SQDG (Ragonese et al. 2014). This lipidomicbased advanced approach is envisaged as a promising tool for elucidation of
seaweed lipid fingerprints, for understanding their metabolism, dependence of environmental conditions, for and biotechnological development of seaweed edible
products and bioactive compounds.
4.5.2 Lipidomic Changes in Seaweed Acclimation Strategies
to Abiotic/Biotic Stress
Lipids are an integral part of cellular membrane and, thus, constitute a part of the
first line of defense against any abiotic/biotic perturbation/stresses. Lipids play a
crucial role in maintaining membrane fluidity in seaweeds by modulating the levels
of PUFAs and inducing FA oxidation cascade during oxidative stress, which further
leads to induction of defense-related genes/enzymes (Dittami et al. 2011, 2012;
Gravot et al. 2010; Kumar et al. 2010a, b, 2011; Kumari et al. 2014b, 2015; Ritter
et al. 2014). Recently, the role of lipids and targeted and nontargeted GC-MS-based
metabolomic approaches to reveal the role of fatty acids, LC-ESI-MS-based
approaches to reveal the role of oxylipins, and other lipid molecules in seaweed
defense strategies against salinity, desiccation, metal, diurnal oscillations, wounding, and other stresses has been reviewed (Kumar et al. 2016 and references therein).
Thus, hereby, updated information of lipidomic changes in seaweed acclimation
strategies to abiotic/biotic stress unraveled by advanced shotgun or CLASS approach
is discussed.
ESI-MS-based shotgun lipidomic approach was for the first time used to
unravel the physiological roles of polar lipid metabolites including lipid classes,
fatty acids, and oxylipins in green seaweed Ulva lactuca Linnaeus under nutritional constraints of nitrate and phosphate (Kumari et al. 2014b). They deciphered
reactive oxygen species (ROS)-mediated nonenzymatic lipid peroxidation due to
nutritional limitation- induced oxidative stress in U. lactuca. To combat this nutritional stress, U. lactuca thalli undergo lipid remodeling including shift in lipid
classes and fatty acids (SFA/UFA), oxylipins (C18- and C20-derived hydroxyoxylipins) to combat nutritional stress. U. lactuca accumulated DGDG, SQDG, and
DGTS when deprived of either nitrate, phosphate, or both, while supplementation
of nutrients, especially nitrate, led to retrieval of lost MGDG. Similarly, glycero4 Seaweed Lipidomics in the Era of ‘Omics’ Biology: A Contemporary Perspective
(mainly containing C14/C16 saturated FAs and C18/C16 unsaturated FA moieties)
in Sargassum horneri (Turner) C. Agardh using RPLC-MS/MS, with MGDGs containing 18:2 at sn-2 position showing reduced triglycerides and FA accumulation in
adipocytes. HILIC-ESI/IT-TOF-MS was used to analyze partial lipidomic profiles
of a few seaweeds including Pterocladiella capillacea (S. G. Gmelin) Santelices &
Hommersand containing lipid classes, viz., PG, PC, PI, LPI, PS, LPE, DGDG,
SQDG, and SQMG, Asparagopsis taxiformis (Delile) Trevisan had a single SGMG,
and Dictyota dichotoma (Hudson) J. V. Lamouroux mainly contained glycerophospholipids PC, LPE, SQMG, and SQDG (Ragonese et al. 2014). This lipidomicbased advanced approach is envisaged as a promising tool for elucidation of
seaweed lipid fingerprints, for understanding their metabolism, dependence of environmental conditions, for and biotechnological development of seaweed edible
products and bioactive compounds.
4.5.2 Lipidomic Changes in Seaweed Acclimation Strategies
to Abiotic/Biotic Stress
Lipids are an integral part of cellular membrane and, thus, constitute a part of the
first line of defense against any abiotic/biotic perturbation/stresses. Lipids play a
crucial role in maintaining membrane fluidity in seaweeds by modulating the levels
of PUFAs and inducing FA oxidation cascade during oxidative stress, which further
leads to induction of defense-related genes/enzymes (Dittami et al. 2011, 2012;
Gravot et al. 2010; Kumar et al. 2010a, b, 2011; Kumari et al. 2014b, 2015; Ritter
et al. 2014). Recently, the role of lipids and targeted and nontargeted GC-MS-based
metabolomic approaches to reveal the role of fatty acids, LC-ESI-MS-based
approaches to reveal the role of oxylipins, and other lipid molecules in seaweed
defense strategies against salinity, desiccation, metal, diurnal oscillations, wounding, and other stresses has been reviewed (Kumar et al. 2016 and references therein).
Thus, hereby, updated information of lipidomic changes in seaweed acclimation
strategies to abiotic/biotic stress unraveled by advanced shotgun or CLASS approach
is discussed.
ESI-MS-based shotgun lipidomic approach was for the first time used to
unravel the physiological roles of polar lipid metabolites including lipid classes,
fatty acids, and oxylipins in green seaweed Ulva lactuca Linnaeus under nutritional constraints of nitrate and phosphate (Kumari et al. 2014b). They deciphered
reactive oxygen species (ROS)-mediated nonenzymatic lipid peroxidation due to
nutritional limitation- induced oxidative stress in U. lactuca. To combat this nutritional stress, U. lactuca thalli undergo lipid remodeling including shift in lipid
classes and fatty acids (SFA/UFA), oxylipins (C18- and C20-derived hydroxyoxylipins) to combat nutritional stress. U. lactuca accumulated DGDG, SQDG, and
DGTS when deprived of either nitrate, phosphate, or both, while supplementation
of nutrients, especially nitrate, led to retrieval of lost MGDG. Similarly, glycero4 Seaweed Lipidomics in the Era of ‘Omics’ Biology: A Contemporary Perspective