Fatty acid and molecular species compositions of the major diacy-glycerolphospholipids from muscle of crustacean metapenaeus istebbingi nobili adapted to different salinities

Phospholipid composition and metabolism were studied in the tropical crustacean [Metapenaeus istebbingi Nobili] muscle. Muscle tissue is rich in diphosphatidylglycerol [DPG] and abundant in monounsaturated fatty acids [oleic acid, 18: 1 n-9] and the long chain polyunsaturated fatty acids, eicosapentenoic [20: 5 n-3] and docosahexaenoic acid [22: 6 n-3] in both brackish-water [15.6 mg/L] and seawater [37.8 mg/L]. The level of phosphatides existed between tissues of shrimp from diluted media and concentrated media was significantly different. The muscle tissue of Metapenaeus istebbingi Nobili in seawater contains much more unsaturated phosphatidylethanolamine [PE]. The accumulation of 18: 1/22: 6, dipolyunsaturated fatty acids [20: 5/20: 5 and 20: 5/22: 6] and introduction of cis delta 9 double bond [18: 1 n-9] into sn-1 position in combination of the phospholipid molecule of seawater animals rendered this species more fluid membrane than another ones. Also, in phosphatidylcholine [PC] and phosphatidylethanolamine [PE], the polyunsaturated fatty acids of the linolenic type were preferentially located in the beta-position [sn-2]. Lipids of seawater crustaceans appear more fluid than brackish-water crustaceans as indicated by the degree of index of unsaturation fatty acids. Lipid changes may indicate the existence of functional differences among crustaceans with respect to their ability to allosteric transition

Marine-fish are main sources of omega-3 fatty acids

Studies were made on the phospholipid fatty acid composition of the most important aquatic animals more correctly, the poikilothermic and of the omega-3 fatty acid composition, which presumably plays the most important role in the protection of the physical properties of cell membrane. The poikilothermic were freshwater and marine fish. In these species, important difference were discored in the quantitative composition of the omega-3 fatty acids of the phospholipids and in the nature of the fatty acids of the phospholipids comprising the membrane. In freshwater fish, the level of arachidonic [AA, 20: 4 n-4] and linoleic [18: 2 n-6] acids were farily high in all species studied. In marine fish, n-3 fatty acids, mainly docosahexaenoic [DHA, 22: 6 n-3] and eicosapentaenoic [EPA, 20: 5 n-3] acids, were the dominant unsaturated fatty acids [17.4 - 36.1%] and [8.3 - 16.3%], respectively, but n-6 fatty acids, mainly 20.4 n-6, 18: 2 n-6 and docosapentaenoic [22: 5 n-6] acids, were also well represented [1 - 2%], [1.1 - 2.7%] and [0.6 - 1.1%], respectively. The ratio C18: 1/C18: 2 is higher of marine fish than for the freshwater fish and is fairly constant for each group

Influence of different pesticide dethamethrin concentrations on the phospholipid composition of carp erythrocyte plasma membrane

In this study, the effect of different concentrations [0.1, 1.2 and 4 ppm] of deltamethrin on the carp erythrocyte plasma membrane was examined following exposure time 48 and 96 hours. The results showed that, the deltamethrin pollutants significantly [P < 0.01] led to decrease of phosphotidyle ethanolamine [PE], phosphoglycerides [PG] and phosphatidic acids [PA] and high concentrations of it led to eliminates the phosphatidic acids and cardiolipin [CL]. Also, deltamethrin pollutant brought about marked difference in the fatty acid patterns of the phospholipids erythrocyte plasma membrane. The increase concentration leads to an increase in the level of saturated fatty acids primarily palmitic [16: 0] and stearic acid [18: 0] as well as in the level of polyunsaturated fatty acids [PUFAs], especially arachidonic acid [20: 4 n-6]. Of monosaturated fatty acids [MUFAs] palmitoleic acid [16: 1 n-7] and oleic acid [18: 1 n-9] did not increased significantly. At the same time the level of omega-3 polyunsaturated fatty acids eicosapentenoic [DHA, 22: 6 n-3], are significantly [P < 0.01] decreased and this makes membrane more rigid and less permeable

Initiation of lipid peroxidation by iron as [ferric chloride] in hepatic fish microsomes in vivo and vitro

The antioxidant effect of dl-alpha-tochopherol acetate [vitamin E], ascorbic acid [Vitamin C] and reduced glutathione [GSH] were studied in-vivo and in vitro peroxidizing system of fish hepatic microsomes. Lipid peroxidation [LP] measured as malondialdehyde [MDA] compound, was not significant altered and inhibited until the concentrations of these antioxidant reached a critical level which depend on the effectiveness of the oxidative stress. Combination between these antioxidants [dl-alpha-tochopherol and GSH] or [dl-alpha-tochopherol and ascorbic acid] are elicit a marked and ascorbic acid] are elicit a marked and progressive reduction to lipid peroxidation. The rational of the cooperation was discussed on the basis of the hydroperoxyl radical scavenging capacity of vitamin E and the reduction of membrane hydroperoxide by glutathione and ascorbic acid. The inhibition of LP by dl-alpha-tochopherol acetate and glutathione was found concomitantly with a decrease in the concentration of its reduced form and a corresponding increase in oxidized tochopherol and glutathione disulfide levels. The study also investigated the relationship between LP and some enzyme inactivation in fish hepatic microsomes. In microsomes incubated with iron as [ferric chloride], glucose-6-phosphatase [G6P-ase] and cytochrome P-450 [Cyt. P-450] levels were decreased rapidly and concurrently with increased level of thiobarbituric acid-reactive substances. Microsomal nicotinamide adenine dinucleotide phosphate cytochrome-c reductase [Cyt-cRas] little affected during incubation period. Addition of antioxidant partially protected against inactivation of G6P'ase and Cyt P-450, as well as LP induced by ferric chloride

Effects of water pollution with organophosphate [cythion] and organochloride [hexadrin] compounds on the antioxidant enzyme system in carp liver

The present work discussed the response reactions of tissue antioxidant enzymes in fishes as a model system upon exposure to organophosphate [Cythion] and organochloride [Hexadrin]. In the present experiments, changes of antioxidant enzyme activities and lipid peroxidation were studied in carp livers exposed to two different concentrations of these compounds. Antioxidant enzymes were studied. Addition of Hexadrin in water at SC or LC 50 concentrations induced significant [P <0.01] increase in t-SOD and GR-ase enzyme activities as well as in GSH, OH and LP levels of carp liver. Also, the activity of t-SOD, GP-ase and GSH was significantly icreased following exposure to SC [P <0.05] or LC 50 [P <0.01] concentration of Cythion

Omega-3 polyunsaturated fatty acids in relation to fish feeding habit

A correlation was found between the fatty acids composition of feed and lipid metabolism of the fish. The proportion of total n-6 PUFA was higher, while the total n-3 PUFA and the n-3/ n-6 were significantly lower in omnivorous fish as compared with carnivorous and herbivorous fish. The percentages of n-3 PUFA and especially 22:6 n-3 and 20:5 n-3 were higher in the herbivorous fish, while carnivorous fish exhibited the highest level of saturated fatty acids