Comparative Lipidomics Study of Four Edible Red Seaweeds Based on RPLC–Q-TOF

Abstract

Red seaweeds (Rhodophyta) are becoming increasingly important as a food and medicine source in blue biotechnology applications such as functional foods, feeds, and pharmaceuticals. Compared to fatty acid composition and sterols, the lipidome in red seaweeds is still in an early disclosure stage. In this study, the lipidomes of four red seaweeds (Gracilaria sjoestedtii, Gracilaria verrucosa, Gelidium amansii, and Chondrus ocellatus) collected from the coastal area in north China were characterized using reversed-phase liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (RPLC−Q-TOF). Hundreds of lipid molecular species including glycolipids, phospholipids, sphingolipids, glycerolipids, and betaine lipids were identified and quantified. Novel lipids with unique molecular structures such as glucuronosyldiacylglycerols (GlcADG), head-group acylated GlcADG (acGlcADG), and hexose-inositol-phosphoceramides (Hex-IPC) were discovered in red seaweeds for the first time, greatly expanding our knowledge on glycolipids and sphingolipids in seaweeds. Glycolipids were the dominant components (45.6−67.7% of total lipids) with a high proportion of polyunsaturated fatty acids (PUFA) including arachidonic acid (AA) and eicosapentaenoic acid (EPA), indicating the potential nutritional value of the four red seaweeds. The investigated red seaweeds showed a distinctive sphingolipid profile with the t18:1 being the predominant LCB in Cer (41.1−71.5%) and HexCer (91.3−97.9%) except for Gelidium amansii, which had the highest proportion of t18:0. Comparison of lipid profiles among the four red seaweeds revealed that AA-and EPA-glycolipids are good lipid markers for the differentiation of red seaweed samples. The AA proportion in glycolipids of Gracilaria genus was much higher than Gelidium genus and Chondrus genus. This study acquired comprehensive lipid profiles from four red seaweeds, revealing the uniqueness of natural biochemical fingerprints of red seaweeds and further promoting their utilization.

An Update on the Chemical Constituents and Biological Properties of Selected Species of an Underpinned Genus of Red Algae: Chondrus

“…Notably, the SLs profile was marked by the presence of a tetrahydroxy long-chain base (LCB), dehydrophyto-sphingosine (t18:1), which was the most abundant LCB in the Cer and HexCer profile. In GPs, triacylglycerol (TG, 8.31%) and diacylglycerol (DG, 11.94%) have been identified from C. ocellatus [116]. The study highlights the importance of EPA and AA as important lipid biomarkers for the identification of red alga species, including C. ocellatus.…”

“…As mentioned in the review, Song et al [116] assessed the lipidomic profile of C. ocellatus. The study evaluated and compared lipid profiles of four different red seaweed species and documented a few novel lipid compounds that added knowledge on sphingolipids and glycolipids of seaweeds, and added knowledge about the unique and natural fingerprinting profile.…”

“…More recently, the comprehensive lipid profile of C. ocellatus as natural biochemical markers using reversed-phase liquid chromatography coupled with quadrupole timeof-flight mass spectrometry was documented and described as qualitative and semiquantitative lipid data [116]. Lipid composition (%) identified five major classes, including glycolipids (GLs, 56.3%), glycerolipids (GPs, 20.25%), betaine lipids (BL, 0.03%), phospholipids (PLs, 21.3%), and sphingolipids (SLs, 2.13%).…”

Comprehensive Lipid Profile of Eight Echinoderm Species by RPLC–Triple TOF-MS/MS

“…SQDG had the potential ability to be antiviral and antitumor 36 and was also used as an inhibitor of DNA polymerase activity in mammals. 37 However, the content of SQDG in echinoderms was significantly less than that in red 38 and brown 39 seaweeds, and the dominant composition of FA was saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) instead of PUFA.…”

Protective Effect of Sargassum fusiforme Fucoidan against Ethanol-Induced Oxidative Damage in In Vitro and In Vivo Models

“…Thus, a compound that possesses the effect of protecting the body against oxidative stress can be thought of as a potential ingredient for developing a therapeutic agent treatment for liver damage caused by EtOH intake. Seaweeds contain a lot of bioactive compounds such as phenolic compounds, carotenoids, fatty acids, dietary fibers, proteins, polysaccharides, and sterols [15][16][17][18][19][20][21][22][23]. These seaweed-derived compounds possess potent antioxidant activity [24,25].…”