Study of phospholipid molecular species of the green seaweed \(\textit{Halimeda incrassata}\) Lamx. from Truong Sa islands, Vietnam

In this report, by a high performance liquid chromatography (HPLC) - high resolution mass spectrometry (HRMS) method, 7 molecular species of phospholipid in the polar lipid class were identified including phosphatidylinositol (PI) and phosphatidylglycerol (PG). The PI 32:0 (16:0/16:0) and PG 34:3 (16:1/18:2) molecular species have the highest content. PI molecular species are mainly formed by saturated fatty acids (16:0, 18:0) and only one polyunsaturated fatty acids C20:4, while PG species are formed by unsaturated fatty acids (16:1, 18:2 and 18:3) and only one saturated fatty acid C16:0.

Comprehensive study of the lipid from whelk (Chlorostoma rusticum and Neverita didyma) with emphasis on characterization of phospholipid molecular species by shot-gun strategy

In the present study, an effective shot-gun lipidomic methodology was established to determine the glycerophospholipid (GP) molecular species of two species of edible marine whelks (Chlorostoma rusticum and Neverita didyma). Simultaneously, the lipid content, lipid classes, phospholipid (PL) subclasses and fatty acid compositions were also investigated. Over 210 molecular species of GP including glycerophosphocholine, lysoglycerophosphocholine, glycerophosphoethanolamine, lysoglycerophosphoethanolamine, glycerophosphoserine, lysoglycerophosphoserine, glycerophosphoinositol and lysoglycerophosphoinositol were characterized in the two abovementioned whelk species. The predominant GP molecular species contained n-3 long chain polyunsaturated fatty acid (n-3 LC-PUFA), especially docosahexaenoic acid and eicosapentaenoic acid. Meanwhile, PL (57.70-58.86% of total lipids) and PUFA (21.69-37.68% of total FA) take large proportions in whelk lipids. Among PL, phosphatidylcholine (50.58-52.41 mol%) and phosphatidylethanolamine (27.67-32.73 mol%) were dominant. Therefore, marine whelks turn out to be promising source of n-3 LC-PUFA existed in PL form and thus directly contribute to the health benefits of consumer.

Fatty Acid, Lipid Classes and Phospholipid Molecular Species Composition of the Marine Clam Meretrix lyrata (Sowerby 1851) from Cua Lo Beach, Nghe An Province, Vietnam

This study aims to analyze compositions of fatty acids and phospholipid molecular species in the hard clams Meretrix lyrata (Sowerby, 1851) harvested from Cua Lo beach, Nghe An province, Viet Nam. Total lipid of hard clams Meretrix lyrata occupied 1.7 ± 0.2% of wet weight and contained six classes: hydrocarbon and wax (HW), triacylglycerol (TAG), free fatty acids (FFA), sterol (ST), polar lipid (PoL), and monoalkyl diacylglycerol (MADAG). Among the constituents, the proportion of PoL accounted was highest, at 45.7%. In contrast, the figures for MADAG were lowest, at 1.3%. Twenty-six fatty acids were identified with the ratios of USAFA/SAFA was 2. The percentage of n-3 PUFA (ω-3) and n-6 PUFA (ω-6) was high, occupying 38.4% of total FA. Among PUFAs, arachidonic acid (AA, 20:4n-6), eicosapentaenoic acid (EPA, 20:5n-3), docosapentaenoic acid (DPA, 22:5n-3), and docosahexaenoic acid (DHA, 22:6n-3) accounted for 3.8%, 7.8%, 2.2% and 12.0% of total lipid of the clam respectively. Phospholipid molecular species were identified in polar lipids of the clams consisting six types: phosphatidylethalnolamine (PE, with 28 molecular species), phosphatidylcholine (PC, with 26 molecular species), phosphatidylserine (PS, with 18 molecular species), phosphatidylinositol (PI, with 10 molecular species), phosphatidylglycerol (PG, with only one molecular species), and ceramide aminoethylphosphonate (CAEP, with 15 molecular species). This is the first time that the molecular species of sphingophospholipid were determined, in Meretrix lyrata in particular, and for clams in general. Phospholipid formula species of PE and PS were revealed to comprise two kinds: Alkenyl acyl glycerophosphoethanolamine and Alkenyl acyl glycerophosphoserine occupy 80.3% and 81.0% of total PE and PS species, respectively. In contrast, the percentage of diacyl glycero phosphatidylcholine was twice as high as that of PakCho in total PC, at 69.3, in comparison with 30.7%. In addition, phospholipid formula species of PI and PG comprised only diacyl glycoro phospholipids. PE 36:1 (p18:0/18:1), PC 38:6 (16:0/22:6), PS 38:1 (p18:0/20:1), PI 40:5 (20:1/20:4), PG 32:0 (16:0/16:0) and CAEP 34:2 (16:2/d18:0) were the major molecular species.

INVESTIGATION ON CONTENT OF FATTY ACIDS, PHOSPHOLIPIDS, AND PHOSPHOLIPID MOLECULAR SPECIES COMPOSITION OF THE VIETNAMESE CORAL Bebryce sp.

In the fatty acid composition of total lipid of the soft coral Bebryce sp., the concentration of unsaturated fatty acid predominates. The composition of saturated fatty acids is very diverse, including all saturated fatty acids from C14 to C26. The unsaturated fatty acids with high concentration are C20: 4n-6, 20:5n-3, 22:6n-3, 24:5n-6, 26:3n-6, 26:2n-6, 26:2n-7, 28:3n-6. In the fatty acids composition of the studied coral, there is presence of characterized fatty acids for the existence of sponges C25-C28 (demospongic fatty acids) with total content 29,86%. Most of the Bebryce coral species do not have zooxanthellae, therefore, in the fatty acids composition, either it is lack or contains only a small amount of markers fatty acids for zooxanthellae such as 18:5n-3, 18:4n-3, 18:3n-6, 20:4n-3. In the phospholipid content of the soft coral Bebryce sp., there is presence of characterized classes for Cnidarian animals such as phosphatidylethanolamine (PE), phosphatidylchonline (PC), phosphatidylserine (PS), phosphatidylinositol (PI), phosphonolipid is ceramide aminoethylphosphonate (CAEP). PC account for the highest concentration (37,20% of total phospholipid). The molecular species of phospholipid classes of Bebryce sp. for the first time were investigated. In the results, there we 60 phospholipid molecular species identified in 5 classes. The molecular species with high content in the classes were PE 20:4/18:1e, PE 20:4/19:1, PC 20:4/18:0e, PC 20:4/16:0e, PS 24:5/18:0e, PI 24:5/18:0, CAEP18:2base/16:0 and CAEP 18:1base/16:0.