Fatty acid composition,cholesterol and fat‐soluble vitamins of wild‐caught freshwater spiny eel,Mastacembelus simack (Walbaum, 1792)

Because of its local commercial value, the proximate nutritional composition, fatty acid composition, cholesterol and fat‐soluble vitamins of spiny eel (Mastacembelus simack Walbaum, 1792) were determined in 20 specimens caught in Keban Dam Lake, Elaz??, Turkey in September 2009. Moisture, protein, lipid, ash and cholesterol contents of the spiny eel were 75.9, 17.1, 10.9, 1.0% and 52.6 mg per 100 g, respectively. Fatty acid composition showed that total polyunsaturated fatty acids (PUFA) were the highest (37.1%), followed by monounsaturated fatty acids (MUFA, 35.5%) and saturated fatty acids (SFA, 27.4%). The relation between PUFA and SFA (1.35) was comparable to that of some fish species, and PUFA : MUFA : SFA ratio (1.35 : 1.29 : 1) was very close to that recommended by nutritionists. Among the vitamins (A, D, E and K) analyzed, the vitamin E content was highest followed by D, K and A. In conclusion, M. simack is rich in proteins, unsaturated fatty acids and vitamins and low in cholesterol, with a reasonable PUFA : SFA and PUFA : MUFA : SFA ratio as recommended by nutritionists. M. simack can therefore be recommended for human consumption as a good source of nutrition.     

半滑舌鳎受精卵、卵黄囊仔鱼和开口仔鱼氨基酸及脂肪酸的变化

采用气相色谱仪和氨基酸分析仪测定了半滑舌鳎(Cynoglossus semilaevis)受精卵、卵黄囊仔鱼和开口仔鱼的氨基酸与脂肪酸组成的变化。结果表明:总氨基酸组成在受精卵和卵黄囊仔鱼之间变化明显,但是在卵黄囊仔鱼和开口仔鱼之间只有细微的变化。开口仔鱼与其摄食的轮虫的总必需氨基酸组成相关。受精卵、卵黄囊仔鱼、开口仔鱼的游离氨基酸含量分别为139 mg/g、3.6 mg/g和2.5 mg/g,占总氨基酸含量的22.3%、3.6%和2.5%。饱和脂肪酸的总量从受精卵到卵黄囊仔鱼明显下降,但是发育到开口仔鱼含量无显著变化。单不饱和脂肪酸和多不饱和脂肪酸的总量在不同发育阶段无显著变化,而EPA和DHA的含量从卵黄囊仔鱼到开口仔鱼有明显下降。这表明在早期发育阶段半滑舌鳎主要利用饱和脂肪酸作为能量代谢的基质,对饱和脂肪酸的利用程度大于单不饱和脂肪酸和多不饱和脂肪酸。半滑舌鳎似乎需要长链的多不饱和脂肪酸如EPA、DHA和ARA。     

Changes in lipid class and fatty acid composition during development in white seabream (Diplodus sargus) eggs and larvae

To establish the changes which occur during embryogenesis and early larvae development, eggs, yolk-sac larvae (one day old larvae) and absorbed yolk-sac larvae (three day old larvae) of white sea bream were examined for lipid class and fatty acid composition. The development was characterized by a decrease in all lipid classes with the exception of phosphatidylserine (PS) and fatty free acids (FFA) which increased, and sphingomyelin (SM) which remained unchanged. The changes observed in lipid class content and the decrease in fatty acids in total lipid (TL) reflect the utilization and mobilization of lipids during both embryogenesis and early larvae development. Fluctuations in the relative composition of fatty acids in phosphatidylcholine (PC) during development suggest a selective bulk uptake and catabolism of fatty acids in this lipid class. Unlike PC, catabolism of triacylglycerol (TG) fatty acid appears to be non-selective. During development, the decrease in levels of polyunsaturated fatty acids (PUFA) eicosapentaenoic (20:5n-3, EPA) and docosahexaenoic (22:6n-3, DHA) in total lipid denotes their utilization as energy substrate by Diplodus sargus larvae.     

Changes in lipid and fatty acid composition of eggs during development of the beet armyworm, Spodoptera exigua

The dry weight of Spodoptera exigua eggs decreased by 15·9 μg/egg or 64% of initial weight during embryogenesis and development of pharate first instar larvae. Lipid depletion accounts for 36% of this total dry weight loss and this occurs at an essentially constant rate throughout development. This marks S. exigua as an exception since most insects utilize lipids more rapidly during later developmental stages. Lipid depletion is due primarily to triglyceride catabolism, although phospholipids also decrease significantly.Fatty acid composition remains stable during development. In triglycerides, 18:1 is most common followed by 16:0 and 18:2; in the phospholipids, the order of abundance is 18:1, 18:2, and 16:0. Egg fatty acids differ from dietary fatty acids: 16:1 comprises 7% of triglyceride fatty acids although it is not present in the larval media; 18:1 predominates in the egg whereas 18:2 is most abundant in the diet.     

Lipid composition,fatty acid profiles,and lipid‐soluble antioxidants of eggs of the Hermann’s tortoise (Testudo hermanni boettgeri)

The major lipid classes, their fatty acid profiles, and the amounts of the lipid‐soluble components, vitamin E, vitamin A, and carotenoids, were determined for egg yolks of the Hermann’s tortoise (Testudo hermanni boettgeri) with the aim of identifying any features that may potentially impair the adaptation of this endangered species to deteriorations in habitat. Total lipid formed 16% (wt/wt) of the fresh yolk and consisted of (wt/wt) 74.4% triacylglycerol, 18.1% phospholipid, 3.0% cholesteryl ester, and 3.4% free cholesterol. Despite a diet based on green plants, contributing α‐linolenic acid as the main polyunsaturate, this fatty acid formed only 3.8% of the total mass of fatty acid of the total lipid. The main acyl component of the yolk lipids was the monounsaturated fatty acid, oleic acid, which formed 45.6% of the total. The most striking feature of the yolk composition was the almost complete lack of two nutrients, docosahexaenoic acid and vitamin A, which are essential for the developing embryo. Although it is feasible that the embryo synthesizes docosahexaenoic acid from yolk‐derived α‐linolenic acid and also converts yolk‐derived β‐carotene to vitamin A, the yolk is poorly endowed with both these precursors. The stringencies displayed by the yolk composition in this species may limit the flexibility to adapt to changes in the availability of food items when the habitat is threatened. Zoo Biol 20:75–87, 2001. © 2001 Wiley‐Liss, Inc.     

Lipid and fatty acid composition of striped bass (Morone saxatilis) larvae during development

Changes in lipid class, fatty acid composition, protein, and dry and wet weights of fertilized eggs and developing larvae of striped bass (Morone saxatilis) fed with the live food, Artemia, were investigated. A decrease of wet and dry weights and moisture was observed at the beginning of the larval stage. Larvae regained the original moisture level, and wet and dry weights increased steadily after feeding. Total lipids decreased from 190 μg/egg in fertilized eggs to 151 μg/egg during hatching and increased after feeding. When total lipid contents were expressed as a percentage of larval dry weight, a decline of lipid did not occur until after feeding. Total protein, on the other hand, increased right after feeding, but there was some variation between days. Polar lipids increased significantly from 20 μg/egg at the egg stage to 199 μg/larva at 26 days post-hatching (DPH), 2 days before the onset of metamorphosis, while neutral lipids declined from 175 μg/egg to 80 μg/larva during the same time period. Wax/steryl esters decreased from 150 μg/egg in fertilized eggs to 32 μg/larva at 26 DPH. Triacylglycerols dropped from 21 μg/egg to 15 μg/larva before feeding and increased gradually after feeding. In contrast, the level of cholesterol increased 2–3-fold. There was a significant increase of phospholipids, particularly phosphatidylcholine in larvae after feeding. The fatty acid composition of fish larvae was significantly influenced by the diet, Artemia. There was an indication of catabolism of endogenous eicosapentaenoic and docosahexaenoic acids during metamorphosis.     

Length–weight and length–length relationships of four species (Barbus lacerta Heckel, 1843), Oxynoemacheilus angorae (Steindachner, 1897), Squalius lepidus (Heckel, 1843) and Pseudorasbora parva (Temminck & Schlegel, 1846) from the Sirwan River (western Iran)

The study describes the length–weight and length–length relationships for three cyprinid species, namely Barbus lacerta, Squalius lepidus and Pseudorasbora parva, and a balitorid species, Oxynoemacheilus angorae from the Sirwan River (located in Kurdistan and Kermanshah provinces, Iran. This study presents the first reference on LWR for most of the species in their distribution range.     

Changes in the fatty acid composition of Drosophila melanogaster during development and ageing.

In Drosophila melanogaster the saturated fatty acids increase in amount early in pupal development relative to the concentrations in late third instar larvae, then decline to the levels characteristic of one-day-old adults. Conversely, the monounsaturated fatty acids decline in content early in pupal development, then increase late in the pupal period. Lauric acid (12:0), myristic acid (14:0) and palmitoleic acid (16:1) become more prominent and oleic acid (18:1) and palmitic acid (16:0) less prominent as the adult ages. At about 40 days of adult age myristic acid (14:0) begins to decrease and oleic acid (18:1) to increase. Within 20 days of eclosion males and females contain different amounts of myristic acid (14:0), palmitic acid (16:0) and oleic acid (18:1).     

Lipid and fatty acid composition of Antarctic shrimp eggs (Decapoda: Caridea)

Polar Biology - Eggs of the decapod shrimps, Chorismus antarcticus, Nematocarcinus lanceopes and Notocrangon antarcticus were taken to analyse their morphometric, lipid and fatty acid composition....     

Lipid and fatty acid composition of eggs producing larvae with high survival rate in the Japanese eel

Eggs of Japanese eel Anguilla japonica were obtained by artificial induction of maturation. Fertilization and hatching rates, and survival rates of normal larvae were examined. The levels of total lipids and polar lipids (PL) of high quality (HQ; >80% survival rate at 8 days post-hatch) eggs were significantly lower than low quality (LQ; hatching and survival rates were zero) eggs. The docosahexaenoic acid (DHA) level in PL of HQ eggs, however, was significantly higher than in LQ eggs. In contrast to DHA, arachidonic acid level was negatively correlated with egg quality variables and it was lower in HQ than in LQ eggs. Most of the egg lipid and fatty acid components showed larger variation in LQ than in HQ eggs.     

Effect of temperature on fatty acid composition and development of unfed Siberian sturgeon (A. baerii) larvae

The fatty acid metabolism in fish is influenced by various factors, including fish species, water temperature, water environment and diet supply. The aim of present work is to investigate the fatty acid composition of yolk‐stage Siberian sturgeon larvae reared at three different temperatures. Fertilized Siberian sturgeon eggs were transferred to the Lodi Aquaculture Research Center of the University of Milan, divided in three aquaria, each containing three incubators and incubated at 16°C. After hatching the temperature was switched to 16, 19 and 22°C. Larvae sampling was performed at the end of yolk sac reabsorption. No feed was dispensed during the trial. Eggs and larvae were weighed and fatty acid profile was determined by GC‐FID analysis after lipid extraction by chloroform/methanol mixture and fatty acid transesterification by methanolic hydrogen chloride. The fertilized eggs had a weight of 23.27 mg and a lipid content of 2.67 mg/egg. At hatching, the weight was 12.2 (0.17 SD) mg and lipid content 1.9 (0.6 SD) mg/larva. At the end of the trial, larvae mean weight was 33.6 (3.6 SD), 34.7 (1.8 SD) and 36.9 (1.1 SD) mg, while lipid content was 2.0 (0.3 SD), 2.1 (0.3 SD) and 2.0 (0.2 SD) mg for larvae reared at 16, 19 and 22°C respectively, without statistically significant difference. Larvae subjected to the highest water temperature showed a faster yolk‐sac absorption. No differences were found across temperatures regarding survival rates and regarding ontogenic development. The fatty acid composition of larvae was affected by the temperature. Larvae reared at 16°C had the lowest amount of saturated fatty acids, mainly due to a lower palmitic acid content, that was offset by a higher level of linolenic and linoleic acid, if compared with larvae reared at 19°C and 22°C. The study suggests that at a lower temperature sturgeon spare unsaturated fatty acid consuming preferably saturated fatty acids, increasing our knowledge of the fatty acid metabolism in this species.     

Length‐weight and length‐length relationships of Oxynoemacheilus frenatus (Heckel, 1843) and Petroleuciscus esfahani Coad & Bogutskaya, 2010 from the Cheshmeh‐Langan river,Iran

The study presents length‐weight relationships (LWRs) and length‐lenght relationships (LLRs) for two freshwater fish species from the Cheshmeh‐Langan River (Iran; 32°50′N, 50°04′E), a part of the Tigris drainage basin. Fish were sampled by electrofishing (Samus 725M) in August and September 2017. The LWRs and LLRs obtained showed a high level of correlation (r² > .98).     

Biochemical composition of cuttlefish (Sepia esculenta) eggs during embryonic development

Changes in egg volume, water content, proteins, carbohydrates, lipids, amino acids and fatty acids in cuttlefish (Sepia esculenta) were determined during embryogenesis to understand the nutritional requirements in the early life phase. The egg volume and the water content decreased significantly (P<0.05) during early embryonic development, and then increased abruptly after the beginning of organ differentiation. During embryonic development, protein was the major content in the yolk and the per cent composition varied to a large extent (55.19–78.45%) with carbohydrates (9.86–15.56%) and lipids (1.62–2.97%). Proteins and lipids decreased 23.3% and 0.4%, respectively, in dry weight, while carbohydrates increased 0.46%. Total amino acids and essential amino acids (EAAs) were stable during the early embryonic developmental stage, but decreased significantly until the eggs hatched (P<0.05). The largest utilisation of the yolk protein possibly occurred with respect to EAAs (25.7%) because of a decrease in methionine (70.3%), valine (63.0%) and phenylalanine (58.5%). The most important fatty acids were saturated fatty acid (SFA) C16:0 and polyunsaturated fatty acids (PUFAs) C22:6 and C20:5. Unsaturated fatty acids (UFAs) and SFA decreased at a similar rate during embryonic development (5.69% and 6.15%, respectively). For UFAs, monounsaturated fatty acids were consumed at a greater rate than PUFAs (29.6% and 0.05%, respectively).     

Changes in fatty acid composition of winter wheat during frost hardening

Twelve day old winter wheat seedlings (cvs Kharkov, frost hardy and Champlein, less hardy) accumulated linolenic acid at the expense of linoleic acid during controlled hardening. The change was most pronounced in the roots, where it was not specific to the phospholipid fraction. It was less marked in the leaves, but occurred there mainly in the phospholipids. The lack of differences between fatty acid profiles of the two cultivars rules out the explanation of varietal differences in frost hardiness in winter wheat on the basis of major changes in fatty acid unsaturation.     

Changes in fatty acid compositions of mitochondria during embryonic development

1. A general trend among biomembranes of hepatocytes in the developing avian embryo is to display increasing percentages of unsaturated fatty acids, especially oleic acid (C18:1). 2. However, once increasing amounts of thyroxine appear in the plasma, mitochondria begin to exhibit increasing percentages of saturated fatty acids, primarily stearic acid (C18:0). 3. Increasing saturation of mitochondrial membrane lipids can be inhibited by exposure of embryonated eggs to 500 R of X-irradiation. 4. Injection of embryonated eggs with estrone increases the proportion of oleic acid (C18:1) in mitochondrial membranes but a balancing increase in palmitic acid (C16:0) enables their lipids to remain more saturated than unsaturated.     

Genetic diversity of Garra rufa Heckel, 1843 (Teleostei: Cyprinidae) in Anatolia

In the present study, mitochondrial DNA polymerase chain reaction-restriction-fragment length polymorphism (PCR-RFLP) and nuclear DNA inter-simple sequence repeat (ISSR) assays were used to assess the phylogenetic and phylogeographic relationships among Garra rufa samples from Anatolia. The complete mtDNA NADH 3/4 dehydrogenase (ND-3/4) gene amplified by PCR was digested with eight restriction enzymes. These enzymes produced 20 composite haplotypes for G. rufa populations. All the mtDNA haplotypes detected were highly diverged from each other and each lineage had a unique genetic profile. The evaluation of mtDNA PCR-RFLP data coupled with geological history of Anatolia indicated a deep genetic divergence among the mtDNA haplotypes of G. rufa populations from drainages of the Mediterranean and Persian Gulf, suggesting an early isolation of Tigris-Euphrates with Orontes river and other rivers draining into the Mediterranean Sea. In general, data from both mtDNA and nDNA were congruent.