Nonmethylene-interrupted Dienoic Fatty Acids Research Articles

Sexual dimorphism in the gonad lipidome of blue mussels (Mytilus sp.): New insights from a global lipidomics approach

Blue mussels (Mytilus sp.) are an economically important species for European aquaculture. Their importance as a food source is expected to increase in the coming net-zero society due to their low environmental footprint; however, their production is affected by anthropogenic stressors and climate change. During reproduction, lipids are key molecules for mussels as they are the main source of energy on which newly hatched embryos depend in the first days of their development. In this work, blue mussels of different origins are analysed, focusing on the differences in lipid composition between the ovary (BMO) and the testis (BMT). The lipidome of blue mussel gonads (BMG) is studied here by combining traditional lipid profiling methods, such as fatty acid and lipid class analysis, with untargeted liquid chromatography-mass spectrometry (LC-MS) lipidomics. The approach used here enabled the identification of 770 lipid molecules from 23 different lipid classes in BMG. BMT, which consists of billions of spermatocytes, had greater amounts of cell membrane and membrane lipid components such as FA18:0, C20 polyunsaturated fatty acids (PUFA), free sterols (ST), ceramide phosphoethanolamines (CerPE), ceramide aminoethylphosphonates (CAEP), cardiolipins (CL), glycerophosphocholines (PC), glycerophosphoethanolamines (PE) and glycerophosphoserines (PS). In BMO, saturated fatty acids (FA14:0 and FA16:0), monounsaturated fatty acids (MUFA) and other storage components such as C18-PUFA accumulated in triradylglycerolipids (TG) and alkyldiacylglycerols (neutral plasmalogens, TG O-), which, together with terpenes, wax esters and cholesterol esters, make up most of oocytes yolk reserves. BMO also had higher levels of ceramides (Cer) and generally alkyl/alkenyl glycerophospholipids (mainly plasmanyl/plasmenyl PC), suggesting a role for these lipids in vitellogenesis. Non-methylene interrupted dienoic fatty acids (NMID FA), typically found in plasmalogens, were the only membrane-forming PUFA predominantly detected in BMO. The results of this study are of great importance for clarifying the lipid composition of BMG and provide an important basis for future studies on the reproductive physiology of these organisms.

Effect of cadmium exposure on essential omega-3 fatty acids in the edible bivalve Donax trunculus.

Donax trunculus is the most consumed bivalve by the local population of the Northeast Algeria for its nutritional value. Therefore, the aim of the current study was to determine the effects of cadmium (Cd), a known toxic metal, on the alterations in main essential omega-3 fatty acids, i.e., eicosapentaenoic acid (EPA; C20:5n-3) and docosahexaenoic acid (DHA; C22:6n-3), in male and female gonads of D. trunculus during the reproduction period at spring (before spawning). Additionally, this work seeks to describe the relation between EPA and DHA with non-methylene-interrupted dienoic (NMID) fatty acids, and explores their possible contribution of to protect against Cd stress. The samples were collected at El Battah, a relatively clean sea shore, and reared in the laboratory. Physico-chemical parameters such as temperature, pH, salinity, and dissolved oxygen were measured. Cd was added to the rearing water at two sublethal concentrations (LC10 and LC25-96h, as determined previously). A two-way ANOVA analysis indicated significant effects of concentrations and genders for both fatty acids. Our results showed a significant reduction in EPA and DHA concentrations in the both genders, with a strong effect in females. There was also a negative correlation between NMID fatty acids and the two essential omega-3 fatty acids for each gender.

Long-chain PUFA enrichment in microalgae and metabolic dynamics inTapes philippinarumlarvae

The possibility of increasing n-3 and n-6 long-chain polyunsaturated fatty acids (PUFA) content in microalgal mixtures used to feed Tapes philippinarum larvae was explored by lowering culture temperature from 26 to 14 °C. Although fatty acid composition of different microalgal species has a genetic basis, the algal cultures grown at 14 °C significantly increased the content of long-chain n-3 PUFA in Isocrysis galbana and in Thalassiosira pseudonana, while in Tetraselmis tetrathelo, the PUFA increase only involved shorter chain PUFA, namely 16:4n-3 and 18:4n-3. However, larvae fed on the PUFA enriched microalgal mixture did not show improvements in growth and survival performances with respect to the control group fed the microalgal mixture grown at 26 °C. From a biochemical perspective, two key aspects emerged from the results: (i) clam larvae have adequate biotransformation and selection skills to adjust fatty acid profile to their requirements as they can even modulate the incorporation of essential long-chain PUFA as 20:5n-3 and 22:6n-3 when the dietary supply exceeds the physiological requirements; (ii) bivalve can biosynthesize non-methylene-interrupted dienoic (NMID) fatty acids as confirmed by the constancy of relative proportion with larvae growth in spite of the NMID fatty acid absence in the diet.

Biochemical and energy dynamics during larval development of the mussel Mytilus galloprovincialis (Lamarck, 1819)

In the current investigation we analyzed the gross biochemical, lipid class and fatty acid composition throughout different developmental stages (namely, egg, D-shaped larva, pediveliger larva and postlarva) of mussel Mytilus galloprovincialis. Lipid was the main biochemical fraction among egg reserves (counting ca. 80%), and the embryonic activities were fueled by stored triglycerides and esters. Polyunsaturated fatty acid (PUFA) 22:6n3 played a structural role during embryonic development, while monounsaturated fatty acids and other PUFA seemed to be preferentially catabolyzed (e.g. 20:5n3, 18:2n6 or 18:3n3). In the transition from D-shaped to pediveliger larva, all the biochemical fractions increased as nutrients were incorporated exogenously from diet. Non methylene interrupted dienoic fatty acid (NMID) levels were similar to those of some essential fatty acids during development. Lipid fraction increased in postlarvae with respect to pediveliger larvae, and no significant energy losses were detected with metamorphosis. Our results provide useful information for the successful hatchery production of M. galloprovincialis.

Physiological and biochemical changes associated with massive mortality events occurring in larvae of American oyster (Crassostrea virginica)

In this paper, biochemical and physiological analyses were used to characterize changes associated with mortality event occurred during veliger development of American oyster, Crassostrea virginica. Biochemical analyses included the evaluation of lipid classes, fatty acid composition and total protein content. Larval physiology was evaluated by studying feeding activity, enzymes related to energy metabolism, oxidative stress levels and enzymatic antioxidant defenses. These analyses were complemented by bacterial community analyses as well as by measuring larval oyster performance. We observed that mortality events coincided with (1) strong changes in the surrounding bacterial community; (2) a progressive decrease in feeding activity; (3) higher levels of some lipid classes (free fatty acids, diglycerides, and acetone mobile phospholipids); (4) lower levels of phospholipids and protein; (5) higher contents of non-methylene interrupted dienoic fatty acids (22:2 NMI); (6) a decrease in energy metabolism activity (citrate synthase and cytochrome oxidase activities); (7) a higher oxidative stress (lipid peroxidation level); and (8) an activation of antioxidant defences before mortality (glutathione peroxidase and superoxide dismutase). We hypothesized that mortality emergence was related to higher energy consumption coupled with the progressive decline in feeding activity, lowered energy reserves and a decrease in energy metabolism activity. Thus, the low energy availability limited the efficiency of antioxidant defenses, resulting in a higher oxidative stress.

Effects of dietary lipids on the fatty acid composition and lipid metabolism of the green sea urchin Strongylocentrotus droebachiensis

The effects of different dietary lipids (hydrogenated coconut oil, corn oil, linseed oil, and mixtures of corn oil, linseed oil, menhaden oil, and/or soy lecithin) on the fatty acid composition of the sea urchin Strongylocentrotus droebachiensis were investigated. Dietary lipid compositions were reflected in the fatty acid profiles of sea urchin guts, gonads and shells. The shells had the highest level of 20:4n-6 and 20:5n-3, while the highest levels of monounsaturated fatty acids were seen in the guts. Tissue levels of 20:4n-6 and 20:5n-3 were influenced by the dietary levels of 18:2n-6 and 18:3n-3. The addition of soy lecithin to the diet (CLnML) enhanced the production and incorporation of 20:4n-6 in shell and gonad. Sea urchin also synthesized and incorporated 20 and 22 carbon non-methylene-interrupted dienoic fatty acids (NMIDs) in all tissue lipids. The NMID content varied among the different tissues and was influenced by the dietary lipid source. The hydrogenated coconut oil (HCO) diet resulted in the greatest NMID content, while the lowest levels were seen in sea urchins fed diets containing a mixture of corn oil, linseed oil, menhaden oil and lecithin (CLnML). The NMID content was lowest in gut and highest in the shell. Significant levels of mead acid (20:3n-9) were detected in the shells of sea urchins fed the EFA-deficient diet (HCO). The enzymatic capabilities of sea urchins to desaturate and elongate 18:2n-6 to 20:4n-6 and 18:3n-3 to 20:5n-3, as well as the capabilities to de novo synthesize NMID were hypothesized. Possible physiological roles and mechanisms for formation of NMID are discussed.

Lipid remodeling in wild and selectively bred hard clams at low temperatures in relation to genetic and physiological parameters

A temperature decrease usually induces an ordering effect in membrane phospholipids, which can lead to membrane dysfunction. Poikilotherms inhabiting eurythermal environments typically counteract this temperature effect by remodeling membrane lipids as stipulated in the homeoviscous adaptation theory (HVA). Hard clams, Mercenaria mercenaria, can suffer high overwintering mortalities in the Gulf of St Lawrence, Canada. The selectively bred M. mercenaria var. notata can have higher overwintering mortalities than the wild species, thus suggesting that the two varieties have different degrees of adaptation to low temperatures. The objective of this study was to investigate the changes in lipid composition of soft tissues in wild and selected hard clams in relation to their metabolic and genetic characteristics. Clams were placed at the northern limit of their distribution from August 2003 to May 2004; they were exposed to a gradual temperature decrease and then maintained at <0 degrees C for 3.5 months. This study is the first to report a major remodeling of lipids in this species as predicted by HVA; this remodeling involved a sequential response of the phospholipid to sterol ratio as well as in levels of 22:6n-3 and non-methylene interrupted dienoic fatty acids. Hard clams showed an increase in 20:5n-3 as temperature decreased, but this was not maintained during overwintering, which suggests that 20:5n-3 may have been used for eicosanoid biosynthesis as a stress response to environmental conditions. Selectively bred hard clams were characterized by a higher metabolic demand and a deviation from Hardy-Weinberg equilibrium at several genetic loci due to a deficit in heterozygote frequency compared with wild clams, which is believed to impose additional stress and render these animals more vulnerable to overwintering mortality. Finally, an intriguing finding is that the lower metabolic requirements of wild animals coincide with a lower unsaturation index of their lipids, as predicted by Hulbert's theory of membranes as pacemakers of metabolism.

Lipid composition of the hydrothermal vent clam Calyptogena pacifica (Mollusca: Bivalvia) as a trophic indicator

Specimens of the chemoautotrophic symbiont-bearing hydrothermal vent clam Calyptogena pacifica were collected from hydrothermal vents at the Endeavour segment of the Juan de Fuca Ridge. Total lipid was extracted from gill, foot and mantle tissues, and lipid class and fatty acid composition determined by thin layer chromatography with flame ionization detection (TLC–FID), gas chromatography (GC) and gas chromatography with mass spectrometry (GC–MS). An abundance of n–7 monounsaturated fatty acids (MUFA), especially in the gill, reflected the large contribution of chemoautotrophic symbiotic bacteria to the nutrition of this clam. The absence of n–8 MUFA suggests that C. pacifica does not contain methanotrophic symbiotic bacteria. Low levels of highly unsaturated fatty acids (HUFA) such as 20:5 n–3 and 22:6 n–3 were detected in C. pacifica and their presence is attributed to a source other than chemoautotrophic symbiotic bacteria. Significant levels of non-methylene interrupted dienoic fatty acids and eicosatrienoic acid (20:3) were also detected in C. pacifica and it is suggested that these fatty acids are synthesized from n–7 MUFA as alternatives to HUFA. In contrast to shallow water bivalves, elevated levels of triglyceride were detected in the gills compared to the mantle.

Fatty acid compositions of gonadal material and diets of the sea urchin, Psammechinus miliaris: trophic and nutritional implications.

The fatty acid compositions of gonadal material was examined for the sea urchin Psammechinus miliaris (Gmelin) held in aquaria and fed either salmon feed pellets or the macroalga, Laminaria saccharina for 18 months. Gonadal material was also examined from P. miliaris collected from four field sites, including commercial scallop lines encrusted with the mussel, Mytilus edulis, sea cages stocked with Atlantic salmon Salmo salar and two intertidal sea-loch sites, characterised by either a fine mud or a macroalgal substratum. The fatty acid compositions of known and potential dietary material was examined. The proportions of certain fatty acids in the gonads of P. miliaris were significantly affected by diet type and location. Docosahexaenoic acid (DHA) 22:6 n-3 was significantly higher in the gonads of the sea urchins fed salmon feed in aquaria and collected from the salmon cages and scallop lines than in the gonads of the sea urchins fed L. saccharina in aquaria and collected from the intertidal sea loch sites. The salmon feed and the mussel tissue also contained a high proportion of this fatty acid. Stearidonic acid 18:4 n-3 and arachidonic acid 20:4 n-6, however, were found in significantly higher proportions than DHA in the gonads of the sea urchins fed L. saccharina and collected from the two intertidal sea-loch sites. L. saccharina was also found to contain high proportions of stearidonic and arachidonic acid. The gonads of the sea urchins collected from the intertidal site, characterised by a mud substratum, and from the scallop lines were found to contain a lower 18:1 n-9/18:1 n-7 ratio and a higher proportion of branched and odd-chained fatty acids, signifying a high dietary bacterial input, than the sea urchins held in the aquaria and collected from the salmon cage. 20:2 and 22:2 non-methylene-interrupted dienoic fatty acids (NMIDs) were found in P. miliaris fed diets lacking these fatty acids suggesting de novo biosynthesis. These results, therefore, suggest that the proportions/ratios of certain fatty acids in the gonads of P. miliaris could be used to give an indication of the predominant diet type of this species in the wild.

Dietary impact of algal and artificial diets, fed at different feeding rations, on the growth and fatty acid composition of Tapes philippinarum (L.) spat

The effect of lipid supplementation and algal ration on growth and fatty acid composition of juvenile clams, Tapes philippinarum was investigated. A diet of Tetraselmis suecica was supplemented with a lipid emulsion and fed at a daily ration of 0.5, 1.0 and 1.5% WW DW −1 day −1. A mixed algal diet of Isochrysis galbana (clone T-Iso) and T. suecica (1:1 on DW basis) and starvation functioned as positive and negative control treatments, respectively. T. suecica, which contains eicosapentaenoic acid (20:5 n−3) but no docosahexaenoic acid (22:6 n−3), was supplemented with 50% (% of algal dry weight) of a 22:6 n−3-rich emulsion. Higher growth rates of T. philippinarum were associated with higher T. suecica feeding rations. Lipid supplementation resulted in significantly better growth rates of T. philippinarum at a T. suecica ration of 0.5, 1.0 and 1.5% WW DW −1 day −1. The growth promoting effect of lipid supplementation was significantly reduced during 4 consecutive weeks or by increasing the algal feeding ration. Increasing T. suecica rations were associated with a decrease in the % composition of 22:6 n−3 while the 20:5 n−3% composition was hardly affected in the total lipids of T. philippinarum. On the contrary, the absolute concentration of 22:6 n−3 (μg per gram dry weight, μg g DW −1) in the total lipids of T. philippinarum was similar at all T. suecica rations while the 20:5 n−3 concentration significantly increased. The major effect of lipid supplementation on the fatty acid composition of the clams, was a significant increase of the 22:6 n−3% composition in the total lipids, polar lipids and triglycerides. In contrast with 20:5 n−3, the effect of lipid supplementation on the absolute 22:6 n−3 content (μg g DW −1) was more pronounced at a higher T. suecica ration. After a starvation period of 4 weeks, the concentration (μg g DW −1) of all fatty acids was significantly reduced, except the n−7 monoenoic fatty acids (MUFA) and the non-methylene interrupted dienoic fatty acids (NMID). The concentration (μg g DW −1) of the NMID in starved clams and clams fed different diets was similar to the concentration in the initial sample. This indicated that growing spat was actively synthesising NMID and they were selectively retained in unfed animals. The results indicated that either dietary lipid or 22:6 n−3 was a growth-limiting factor when T. suecica was fed at a ration of 0.5, 1 and 1.5% WW DW −1 day −1. A selective retention in starved clams and a preferential accumulation in fed clams was observed for 22:6 n−3 but not for 20:5 n−3 which indicated a greater importance of 22:6 n−3 compared to 20:5 n−3.

Fatty acid characteristics in two symbiont-bearing mussels from deep-sea hydrothermal vents of the south-western Pacific

Two bacteria-bearing mussels,Bathymodiolus breviorandB. elongatus, collected at five deep-sea hydrothermal sites from Lau and Fiji back arc basins (south-west Pacific), were analysed for polar and neutral lipids using gas-liquid chromatography mass spectroscopy (GLC-MS). The respective fatty acid distributions found in gills and mantles were compared to data from a Mediterranean littoral filter-feeding mussel,Mytilus galloprovincialis. The main characteristic common to the gills of the two vent mussels was the high level of (n-7) monounsaturated phospholipid fatty acids, which are supposed to originate from sulphur-oxidizing symbionts. Using palmitoleic, 16:1 (n-7), and vaccenic, 18:1 (n-7), phospholipid fatty acids as bacterial markers, endobacterial biomass was estimated to account for 2–10% of the vent mussel gill volume. Vent mussel tissues were poor in plant-derived polyunsaturated fatty acids, indicating the limited importance of the photosynthesis based material in the metabolism of these hydrothermal vent bivalves. It is suggested that some compounds, such as nonmethylene-interrupted dienoic fatty acids and specific trienoic fatty acids originating from elongation and desaturation of oleic and palmitoleic acids, respectively, were synthesized in order to substitute exogenous plant-derived polyunsaturated fatty acids considered as essential in marine invertebrates. The high level of neutral lipids in vent mussel gills suggests that these compounds are used as a major energy storage material. The neutral lipid/phospholipid ratio in gills emphasized the preponderance of the endosymbionts in vent mussel nutrition. Using this ratio as an index of the physiological state, the symbiosis patterns in different hydrothermal fields were compared.

The pathway of the biosynthesis of non-methylene-interrupted dienoic fatty acids in molluscs

1. 1. The metabolic fate of 1- 14C-acetate administered to the marine bivalve mollusc Mytilus edulis was investigated. 2. 2. The active incorporation of the label in 20:2 non-methylene-interrupted dienoic (NMID) fatty acids was found. 3. 3. Acetate incorporation patterns and specific radioactivity of mussel acids suggest that 22:2Δ7,13 and 22:2/gD7,15 arose by C 2 elongation of 20:2Δ5,11 and 20:2Δ5,13 respectively. 4. 4. The proposed pathway of NMID fatty acid biosynthesis in molluscs is discussed.

Non-methylene-interrupted dienoic fatty acids in molluscs from the sea of Japan

Abstract 1. 1. Structural analysis of the fatty acid fraction isolated from lipids of the mollusc Scapharca broughtoni showed that it was the mixture of two isomers non-methylene-interrupted dienoic (NMID) fatty acids Δ7, 13–22:2 and Δ7, 15–22:2 in the ratio 1:1.56. 2. 2. Fatty acid composition of the seven species of marine bivalves and gastropods was studied. 3. 3. The content of NMID fatty acids varied from 0.7% for Spisula sachalinensis to 20.7% for Scapharca broughtoni . The latter value was the highest that is known for molluscs. 4. 4. The regularity of NMID distribution in bivalve molluscs are discussed.

Occurrence of a 22∶2 nonmethylene interrupted dienoic fatty acid and its seasonal distribution among lipids and tissues of the fresh water bivalveDiplodon delodontus from an isolated environment

LipidsVolume 19, Issue 10 p. 814-814 ErratumFree Access Occurrence of a 22∶2 nonmethylene interrupted dienoic fatty acid and its seasonal distribution among lipids and tissues of the fresh water bivalveDiplodon delodontus from an isolated environment This article corrects the following: Occurrence of a 22∶2 nonmethylene interrupted dienoic fatty acid and its seasonal distribution among lipids and tissues of the fresh water bivalveDiplodon delodontus from an isolated environment C. -E. Irazu, R. J. Pollero, R. R. Brenner, Volume 19Issue 9Lipids pages: 649-655 First Published online: September 1, 1984 C. E. Irazu, C. E. IrazuSearch for more papers by this authorR. J. Pollero, R. J. PolleroSearch for more papers by this authorR. R. Brenner, R. R. BrennerSearch for more papers by this author C. E. Irazu, C. E. IrazuSearch for more papers by this authorR. J. Pollero, R. J. PolleroSearch for more papers by this authorR. R. Brenner, R. R. BrennerSearch for more papers by this author First published: 01 October 1984 https://doi.org/10.1007/BF02534478 The online version of the original article can be found at http://dx.doi.org/10.1007/BF02534524 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume19, Issue10October 1984Pages 814-814 RelatedInformation

Occurrence of a 22∶2 nonmethylene interrupted dienoic fatty acid and its seasonal distribution among lipids and tissues of the fresh water bivalveDiplodon delodontus from an isolated environment.

Realatively high levels of a non-methylene-interrupted dienoic fatty acid were detected in the freshwater molluscDiplodon delodontus. The (7,13) 22∶2 NMID fatty acid was separated from total fatty acids by TLC, and its structure was determined by GLC and reductive ozonolysis. Its seasonal distribution was investigated in different tissues and lipids of the mollusc. High concentrations of this acid were found in polar lipids. The absence of the 22∶2 NMID fatty acid in the lipids of plankton and sediment in the same habitat suggests that it may be biosynthesized by themollusc. Possible synthesis and functions of the NMID fatty acids are discussed.

Distribution of methylene and nonmethylene-interrupted dienoic fatty acids in polar lipids and triacylglycerols of selected tissues of the hardshell clam (Mercenaria mercenaria).

Fatty acid profiles of polar lipids and triacylglycerols were determined for 6 tissues of the hardshell clam (Mercenaria mercenaria), namely, mantle, gill, mouth, foot, digestive tract/gonadal tissue and adductor muscle. The largest concentrations of nonmethylene-interrupted dienoic (NMID) fatty acids were found in the gill, mantle, and foot. Structural analyses were undertaken to determine the double bond configurations of the various NMID isomers. The major 22C NMID species were Δ7,13- and Δ7,15-docosadienoic acid. The major 20C NMID species were Δ7,11- and Δ7,13-eicosadienoic acid and Δ5,11-eicosadienoic acid.

Potential for employing the distribution of anomalous non-methylene-interrupted dienoic fatty acids in several marine invertebrates as part of food web studies.

A group of homologous, nonmethylene-interrupted dienoic fatty acids (NMID) recently reported in oysters has been found in several other shellfish species and also in other marine phyla. The distribution of most other "normal" fatty acids among several species of shellfish is basically similar but mantle lipids from two other molluscan species, both squid, differ radically. The squid mantle fatty acids do not include NMID, suggesting that in molluscs NMID may accumula-e primarily in filter-feeders or herbovores. The distribution of these anomalous fatty acid components in higher species suggests that they reflect invertebrates in the diet and are biochemically inert.

Occurrence and chemical structure of nonmethylene-interrupted dienoic fatty acids in American oyster Crassostrea virginica.

The American oyster, Crassostrea virginica, was found to contain structurally homologous nonmethylene-interrupted dienoic (NMID) fatty acids. The major C20 and C22 nonmethylene-interrupted dienoic fatty acid isomers were shown to occur as two pairs of homologues 5,13-20:2 with 7,15-22:2 and 5,11-20:2 with 7,13-22:2. A combination of analytical procedures was required for conclusive structure determination.