Changes In Fatty Acid Composition Research Articles

Sulfamethoxazole and tetracycline induced alterations in biomass, photosynthesis, lipid productivity, and proteomic expression of Synechocystis sp. PCC 6803.

Since antibiotics show hormesis effects in cyanobacteria at the nanogram per liter concentration level, the possibility for two commonly used antibiotics (sulfamethoxazole and tetracycline) to increase lipid productivity in Synechocystis sp. PCC 6803 was assessed in the present study. The two target antibiotics significantly promoted (p < 0.05) the biofuel productivity of Synechocystis sp. PCC 6803 through the increase of both biomass and lipid content. Sulfamethoxazole and tetracycline significantly stimulated (p < 0.05) cyanobacterial growth by upregulating proteins related to cell differentiation, cell division, and gene expression; significantly enhanced (p < 0.05) the photosynthetic activity by upregulating photosynthesis-related proteins; and significantly increased (p < 0.05) the lipid content in cyanobacterial cells by downregulating carbohydrate catabolic proteins and carbohydrate transport proteins. Due to the altered expression pattern of biosynthesis-related proteins, the two antibiotics increased the proportion of monounsaturated fatty acids, while tetracycline reduced the proportions of saturated and polyunsaturated fatty acids. The changes in fatty acid composition may improve the combustion performance of biofuel. This study provided insights into the application of antibiotics in cyanobacteria-based biofuel production. Graphical abstract.

Changes of milk fatty acid composition in four lipid classes as biomarkers for the diagnosis of bovine ketosis using bioanalytical Thin Layer Chromatography and Gas Chromatographic techniques (TLC-GC)

The aim of this study was to extend the limited research available on the association between the concentration of milk fatty acids and the elevated plasmatic value of β-hydroxybutyrate (BHB) in early lactation of dairy cows. Fifty-four Holstein Friesian dairy cows were enrolled in the study. All animals were classified on the basis of their blood BHB concentration: BHB ≥ 1.0 mmol/L (BHB-1, sick group) and BHB ≤ 0.99 mmol/L (BHB-0, healthy group). Using Thin Layer Chromatography (TLC), four lipid classes (cholesterol esters -CE-, phospholipids -PL-, free fatty acids -FFA- and triacylglycerols -TAG-) were separated, and then the fatty acid (FA) composition was determined by High Resolution Gas Chromatography coupled with Flame Ionization Detector/Mass Spectrometer (HRGC-FID/MS). The FA profiles were used to investigate the diagnostic potential value of milk fatty acids for the correct classification of cows with BHB concentration above the established threshold (BHB < 1.0 mmol/L). Boruta Test and Receiver Operating Characteristic curves (ROC) were used to identify which FA and their thresholds of concentration could be used when animals presented hyperketonemia. The research has identified fourteen FA, belonging to CE, FFA, and TAG classes, useful for an association with BHB-1. These compounds, with predictive value for the development of hyperketonemia, could be considered valuable biomarkers. Further studies on a wider sampling, based on clinical and therapeutic approach, will be necessary to confirm, by bioanalytical chromatographic approaches, if these predictive FA will change between healthy and sick animals. New approaches in relation on the administration of different diets or supplements, and administration of drugs might improve the prevention of hyperketonemia.

Effects of buffer salts on the freeze-drying survival rate of Lactobacillus plantarum LIP-1 based on transcriptome and proteome analyses

Buffer salts are often added to culture medium to promote bacterial growth. However, we found that buffer salts can improve the freeze-drying survival rate. In this experiment, the mechanisms for the effects of different buffer salts on the survival rate of freeze-dried strains were examined. The results showed that buffer salts had important effects on the freeze-drying survival rate of L. plantarum LIP-1 that were related to changes in fatty acid composition. Different buffer salts affected the expression of fatty acid metabolic genes. A new gene cluster that regulates fatty acid metabolism and synthesis was discovered. Potassium ions in buffer salts upregulated the trkA gene and lysR-type transcription factor, and then upregulated the expression of fatty acid synthesis-related acc and fab family genes. These genes help to extend the fatty acid carbon chain and promote the unsaturated fatty acids content, which improves cell membrane fluidity and improves resistance to freeze-drying.

Composition and Functionality of Lipid Emulsions in Parenteral Nutrition: Examining Evidence in Clinical Applications

Lipid emulsions (LEs), an integral component in parenteral nutrition (PN) feeding, have shifted from the primary aim of delivering non-protein calories and essential fatty acids to defined therapeutic outcomes such as reducing inflammation, and improving metabolic and clinical outcomes. Use of LEs in PN for surgical and critically ill patients is particularly well established, and there is enough literature assigning therapeutic and adverse effects to specific LEs. This narrative review contrarily puts into perspective the fatty acid compositional (FAC) nature of LE formulations, and discusses clinical applications and outcomes according to the biological function and structural functionality of fatty acids and co-factors such as phytosterols, α-tocopherol, emulsifiers and vitamin K. In addition to soybean oil-based LEs, this review covers clinical studies using the alternate LEs that incorporates physical mixtures combining medium- and long-chain triglycerides or structured triglycerides or the unusual olive oil or fish oil. The Jaded score was applied to assess the quality of these studies, and we report outcomes categorized as per immuno-inflammatory, nutritional, clinical, and cellular level FAC changes. It appears that the FAC nature of LEs is the primary determinant of desired clinical outcomes, and we conclude that one type of LE alone cannot be uniformly applied to patient care.

Differential sensitivity of fatty acids and lipid damage in Microcystis aeruginosa (cyanobacteria) exposed to increased temperature

Changes in fatty acid (FA) composition can mean a mechanism of acclimation of Cyanobacteria to climate change. The objective of the present study was to evaluate the effects of increased temperature on M. aeruginosa cultures in terms of FA content, lipid damage, biomass and reactive oxygen species (ROS). Unicellular cultures were exposed to high (29 °C) and control (26 °C) temperature for 12 days. Differential sensitivity of ω3 FAs was observed after 2 days of exposure to elevated temperature (29 °C). Also, no significant differences in ROS content at different temperatures were observed although there was a significant decrease compared to the value at the start of the incubation. Thus, low FA peroxidation of selected ω6 PUFAs and potentially increased activation of antioxidant systems, resulting in lower lipid damage (on average 35%), could explain the strong acclimation to high temperature as shown by the increased growth rate (11%) compared to the control conditions. In high temperature conditions we found a retarded desaturation to 18:3ω3 and 18:4ω3 PUFAs which were 40% lower compared with control at the end of incubation.Overall, growth rate and omega-6 FA were increased at high temperature as a mechanism of successful acclimation. This is highly relevant for the ecological role of M. aeruginosa as food source for grazers. A reduced FA level can have serious implications for the flow of energy and thus the overall functioning of the ecosystem.

Long-term hypercortisolism induces lipogenesis promoting palmitic acid accumulation and inflammation in visceral adipose tissue compared with HFD-induced obesity.

Glucocorticoids (GCs) play critical roles in adipose tissue metabolism. Here, we compare in a mouse model the effects of chronic glucocorticoid excess and diet-induced obesity on white adipose tissue mass and distribution, by focusing on visceral adipose tissue (VAT) fatty acid composition changes, the role of de novo lipogenesis (DNL) and the inflammatory state. We used a noninvasive mouse model of hypercortisolism to compare GC-induced effects on adipose tissue with diet-induced obesity [high-fat diet (HFD) 45%] and control mice after 10 wk of treatment. Subcutaneous adipose tissue (SAT) and VAT mass and distribution were measured by nuclear magnetic resonance imaging (NMRI). Fatty acid composition in VAT was analyzed by NMR spectroscopy and gas chromatography. Gene expression of key enzymes involved in DNL was analyzed in liver and VAT. Macrophage infiltration markers and proinflammatory cytokines were measured by gene expression in VAT. HFD or GC treatment induced similar fat mass expansion with comparable distribution between SAT and VAT depots. However, in VAT, GCs induce DNL, higher palmitic acid (PA), macrophage infiltration, and proinflammatory cytokine levels, accompanied by systemic nonesterified fatty acid (NEFA) elevation, hyperinsulinemia, and higher homeostatic model assessment for insulin resistance (HOMA-IR) levels compared with diet-induced obesity. Thus, chronic hypercortisolism induces DNL and fatty acid composition changes toward increased SFA and reduced polyunsaturated fatty acid (PUFA) levels in VAT, promoting macrophage recruitment and proinflammatory cytokines, suggesting a worse cardiometabolic profile even compared with HFD mice.

The effect of drying temperature of milk thistle seeds on quality and bioactive compounds in the lipid fraction

Milk thistle oils are available on the market and appeal to consumers because of their healthy properties as cold-pressed oils. The raw material for producing such oils is purchased from a range of domestic and foreign sources. The aim of this work was to determine the effect of drying temperature on the peroxide value, acid value, fatty acid composition, tocopherol and phytosterol contents in the lipid fraction extracted from milk thistle seeds. The seeds were purchased in three different farms and were dried in a thin layer at 40 °C, 60 °C, 80 °C, 100 °C, 120 °C, and 140 °C. The level of phytosterols and the fatty acid composition were determined using GC-FID, while tocopherols concentrations were determined using HPLC. The study showed that the quality of seeds used in the production of oil varies. The drying of milk thistle seeds using air cooler than 80 °C caused no statistically significant changes in AV, p-AnV, phytosterol levels, tocopherols, or SFA levels. Drying temperatures in the 100–140 °C range caused significant losses of phytosterols and tocopherols and also resulted in changes in fatty acid composition. When seeds were dried at 140 °C, phytosterol levels dropped by 19–23%, tocopherols by 10–23%, MUFA by 30%, and PUFA by 11%.

The effects of elevated CO2 concentrations on changes in fatty acids and amino acids of three species of microalgae

ABSTRACT Microalgae are important producers in aquatic ecosystems and are valuable for biodiesel production and feed supply industries. Three such microalgae, Nannochloropsis oceanica (Eustigmatophyceae), Dunaliella salina (Chlorophyceae), and Chlamydomonas reinhardtii (Chlorophyceae), were cultured at two pCO2 (400 ppm, 1000 ppm) to investigate changes in fatty acid and amino acid composition. Elevated pCO2 increased C16:0, C18:3, C20:5, total saturated fatty acid (SFA), total polyunsaturated fatty acid (PUFA), and total essential amino acid (EAA) content in N. oceanica. High CO2 concentration reduced C16:0 and total SFA content, but increased C18:3, total PUFA, and total EAA accumulation, in D. salina. Changes in C. reinhardtii were the opposite of those in D. salina. Results indicated that higher pCO2 may improve the quality of biodiesel produced by N. oceanica and C. reinhardtii. Furthermore, in N. oceanica and D. salina, increased CO2 concentration elevated nutrient levels but resulted in reduced nutrient quality in C. reinhardtii. Our results can help predict nutritional changes in microalgae at elevated pCO2, and provide insight into production of biodiesel and animal feed by microalgae.

Polystyrene microplastics decrease accumulation of essential fatty acids in common freshwater algae

Despite growing concern about the occurrence of microplastics in aquatic ecosystems there is only rudimentary understanding of the pathways through which any adverse effects might occur. Here, we assess the effects of polystyrene microplastics (PS-MPs; <70 μm) on a common and widespread algal species, Chlorella sorokiniana. We used laboratory exposure to test the hypothesis that the lipids and fatty acids (FAs) are important molecules in the response reactions of algae to this pollutant. Cultivation with PS-MPs systematically reduced the concentration of essential linoleic acid (ALA, C18:3n-3) in C. sorokiniana, concomitantly increasing oleic acid (C18:1n-9). Among the storage triacylglycerols, palmitoleic and oleic acids increased at the expenses of two essential fatty acids, linoleic (LIN, C18:2n-6) and ALA, while PS-MPs had even more pronounced effects on the fatty acid and hydrocarbon composition of waxes and steryl esters. The FA composition of two major chloroplast galactolipids, monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG), were affected implying changes in the conformational structure of photosynthetic complexes in ways that can impair the photosynthesis. These data reveal how exposure to polystyrene microplastics can modify the concentrations of lipid molecules that are important intrinsically in cell membranes, and hence the lipid bilayers that could form an important barrier between algal cellular compartments and plastics in the aquatic environment. Changes in lipid synthesis and fatty acid composition in algae could also have repercussions for food quality, growth and stressor resistance in primary consumers. We advocate further studies of microplastics effects on the lipid composition of primary producers, and of their potential propagation through aquatic food webs.

The WRKY6 transcription factor affects seed oil accumulation and alters fatty acid compositions in Arabidopsis thaliana.

In rapeseed, the oil content of the seed not only supplies energy for seed germination and seedling development but also provides essential dietary nutrients for humans and livestock. Recent studies have revealed that many transcription factors (TFs) regulate the accumulation of fatty acids (FAs) during seed development. WRKY6, a WRKY6 family TF, was reported to serve a function in the plant senescence processes, pathogen defense mechanisms and abiotic stress responses. However, the precise role of WRKY6 in influencing FA accumulation in seeds is still unknown. In this study, we demonstrate that WRKY6 has a high expression level in developing seeds and plays an essential role in regulating the accumulation of FAs in developing seeds of Arabidopsis. Mutation of WRKY6 resulted in significant increase in seed size, accompanied by an increase in FA content and changes in FA composition. Ultrastructure analyses showed that the absence of WRKY6 resulted in more and higher percentage of oil body in the cell of mature seeds. Quantitative real-time PCR analysis revealed changes in the expression of several genes related to photosynthesis and FA biosynthesis in wrky6 mutants at 10 or 16 days after pollination. These results reveal a novel function of WRKY6 influencing seed oil content and FAs compositions. This gene could be used as a promising gene resource to improve FA accumulation and seed yield in Brassica napus through genetic manipulation.

ANGPTL3 deficiency alters the lipid profile and metabolism of cultured hepatocytes and human lipoproteins

Loss-of-function (LOF) mutations in ANGPTL3, an inhibitor of lipoprotein lipase (LPL), cause a drastic reduction of serum lipoproteins and protect against the development of atherosclerotic cardiovascular disease. Therefore, ANGPTL3 is a promising therapy target. We characterized the impacts of ANGPTL3 depletion on the immortalized human hepatocyte (IHH) transcriptome, lipidome and human plasma lipoprotein lipidome. The transcriptome of ANGPTL3 knock-down (KD) cells showed altered expression of several pathways related to lipid metabolism. Accordingly, ANGPTL3 depleted IHH displayed changes in cellular overall fatty acid (FA) composition and in the lipid species composition of several lipid classes, characterized by abundant n-6 and n-3 polyunsaturated FAs (PUFAs). This PUFA increase coincided with an elevation of lipid mediators, among which there were species relevant for resolution of inflammation, protection from lipotoxic and hypoxia-induced ER stress, hepatic steatosis and insulin resistance or for the recovery from cardiovascular events. Cholesterol esters were markedly reduced in ANGPTL3 KD IHH, coinciding with suppression of the SOAT1 mRNA and protein. ANGPTL3 LOF caused alterations in plasma lipoprotein FA and lipid species composition. All lipoprotein fractions of the ANGPTL3 LOF subjects displayed a marked drop of 18:2n-6, while several highly unsaturated triacylglycerol (TAG) species were enriched. The present work reveals distinct impacts of ANGPTL3 depletion on the hepatocellular lipidome, transcriptome and lipid mediators, as well as on the lipidome of lipoproteins isolated from plasma of ANGPTL3-deficient human subjects. It is important to consider these lipidomics and transcriptomics findings when targeting ANGPTL3 for therapy and translating it to the human context.

Changes in chemical properties and oxidative stability of refined vegetable oils during short‐term deep‐frying cycles

In this study, changes in chemical properties, oxidative stability, fatty acid composition (FAC) and Fourier transform infrared (FTIR) spectra of soybean (SBO), rice bran (RBO), canola (CNO), cottonseed (CSO), and sunflower (SFO) oils during short-term deep frying of chickpea splits were determined. Free fatty acid (FFA), peroxide value (PV), p-anisidine value (p-AV), and viscosity of refined vegetable oils increased while the oxidative stability index (OSI) decreased with increment in frying cycles (FCs). The minimum changes in FFA, PV, p-AV, viscosity, and OSI were observed in SBO till fifth FCs. Oil uptake was also low in SBO and high in CNO after 5th and 10th FCs. CNO, RBO, and CSO exhibited higher changes in FAC and FTIR spectra (peak intensities at 3,009, 2,925, 2,854, and 1,745 cm−1) compared to SBO and SFO with increment in FCs. Thus, SBO with admissible ω6/ ω3 ratio (9.42:1) is suitable for short-term deep frying of chickpea splits. Practical applications In the deep-frying process of chickpea splits, five vegetable oils behaved differently in quality and stability characteristics. Soybean oil exhibited minimum changes in FFA content, viscosity, and OSI with increment in frying cycles. Oil uptake was lowest in soybean oil and it contains a desirable FAC for health benefits. Thus, soybean oil is recommended for short-term deep-frying operations among the studied vegetable oils.

Changes in Fatty Acid Composition and Lipid Content Occurring in Potato Leaves during Cold Hardening: the Role of ∆12-Acyl-Lipid Desaturase

The qualitative composition and changes in the total fatty acid (FA) content in leaves of wild-type potato (Solanum tuberosum L., cv. Desnitsa) plants and plants transformed with the desA gene of Δ12-acyl-lipid desaturase from Synechocystis sp. PCC 6803 have been studied under cold hardening conditions (6 days at 5°С). During cold adaptation, plants of both types increase their cold resistance, but transformed plants significantly exceed control ones in relation to this parameter. Following cold hardening, the content of total etherified FA in leaves of control plants increases by almost 25% due to the decrease in the content of saturated FA and almost 30% increase in the content of polyunsaturated FA (PUFA); the growth of the PUFA content is provided mainly by linoleic (C18:2) and linolenic (C18:3) acids. Nonhardened leaves of transformed plants are characterized by the same FA content (especially C18:3) as the leaves of hardened control plants. Due to this fact, increase in the total FA content in hardened transformants is not so significant as in the control; at the same time, the content of linoleic (C18:2) acid increases by 30% (the calculated activity index for ∆12-desaturases also slightly increased). The growth of a hexadecatrienic (С16:3) acid content in transformed plants probably results from a low-temperature activation of potato ω3-desaturases. The obtained data allow one to suppose that the higher resistance of transformed plants compared to control ones is connected with a constitutively increased PUFA content and determines more efficient cold hardening of such plants.

Changes in behavior and fatty acid composition induced by long-term reduction in murine Δ6-desaturation activity

Polyunsaturated fatty acids (PUFAs), especially arachidonic acid (ARA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), play an important role in biological regulation. In our previous study using mice deficient in Δ6 desaturase (D6D), we reported that ARA is required for body growth, while DHA is necessary for functional development. In mammals, ARA and DHA are supplied directly or by synthesis from linoleic acid (LA) and α-linolenic acid (ALA). However, as desaturase enzyme activity is immature or low in newborns, and humans with minor alleles of the gene encoding desaturase, respectively, they require dietary supplementation with ARA and DHA. To investigate how the body reacts to a long-term reduction in fatty acid synthesis, we measured behavioral changes and fatty acid composition in mice heterozygous for the D6D null mutation with reduced D6D activity fed a diet containing only LA and ALA as PUFAs. During the growth-maturity period, heterozygous mice showed a slightly change in interest and curiosity compared with the wild-type group. ARA levels were decreased in the brain and liver in the heterozygous group, especially during the growth-maturity period, whereas DHA levels were decreased in the liver only in the old age period, suggesting that there are differences in the synthesis of and demand for ARA and DHA during life. For newborns, and humans with minor alleles with low desaturase activity, direct ARA intake is particularly important during the growth-maturity period, but they may need to be supplemented with DHA in the old age period. Further research is needed to determine the optimal intake and duration of these fatty acids.

Debittering of cold pressed grapefruit seed oil by metal‐organic framework adsorbents

The aim of this study was to remove bitterness from cold pressed grapefruit seed oil. Seven different metal-organic frameworks and three natural clays (commercial bleaching earth, zeolite, and sepiolite) were used as adsorbents. In addition, water washing and solvent extraction treatments were done. After the treatments, oil physicochemical properties, fatty acid, sterol, tocopherol and flavonoid compositions, sensory flavor profile analysis, and consumer tests were completed. Results indicated that adsorbent treatments were better for oil color, turbidity, free fatty acidity, and p-anisidine values than those of the washing and extraction treatments. Although there was no significant change in oil fatty acid and sterol composition, some loss in tocopherol content was observed after the treatments. Sensory descriptive analysis indicated that oil bitterness, spicy, and throatcatching scores decreased by 62.79%, 42.42%, and 58.97% by chromium metal-organic framework (Cr-MOF) treatment. In conclusion, Cr-MOF treatment successfully removed the bitterness from cold pressed grapefruit seed oil. Practical applications The bitter taste of cold pressed grapefruit seed oil was almost totally removed by adsorbent treatment with the laboratory synthesized chromium metal-organic frameworks. Sensory flavor profile analysis and consumer test indicated that the treated oil can be directly consumed as edible oil. This method could have practical importance for those who interested to produce and use cold pressed grapefruit seed oils for edible purposes.

A single meal has the potential to alter brain oxylipin content

Our objective was to determine whether consumption of a single meal has the potential to alter brain oxylipin content. We examined the cerebrum of mice fed a single high-fat/high-sucrose Western meal or a low-fat/low-sucrose control meal, as well as fasted mice. We found no changes in fatty acid composition of cerebrum across the groups. The cerebral oxylipin profile of mice fed a Western meal is distinct from the profile of mice fed a low-fat/low-sucrose meal. Cerebral gene expression of cyclooxygenase 1, cyclooxygenase 2, and epoxide hydrolase 1 were elevated in Western meal-fed mice compared to low-fat/low-sucrose meal-fed mice. Mice that consumed either meal had lower gene expression of cytochrome P450, family 2, subfamily j, polypeptide 12 than fasted mice. Our data in this hypothesis-generating study indicates that the composition of a single meal has the potential to alter brain oxylipins and the gene expression of the enzymes responsible for their production.

Influence of feeding thermally peroxidized soybean oil on growth performance, digestibility, gut integrity, and oxidative stress in nursery pigs.

The objectives of the current experiments were to evaluate the effect of feeding soybean oil (SO) with different levels of peroxidation on lipid, N, and GE digestibility, gut integrity, oxidative stress, and growth performance in nursery pigs. Treatments consisted diets containing 10% fresh SO (22.5 °C) or thermally processed SO (45 °C for 288 h, 90 °C for 72 h, or 180 °C for 6 h), each with an air infusion of 15 L/min, with postprocessing peroxide values of 7.6, 11.5, 19.1, and 13.4 mEq/kg and p-anisidine values of 1.92, 6.29, 149, and 159, for the 22.5 °C, 45 °C, 90 °C and 180 °C processed SO, respectively. In experiment 1, 64 barrows (7.1 ± 0.9 kg initial BW) were randomly allotted into 2 rooms of 32 pens and individually fed their experimental diets for 21 d, with a fresh fecal sample collected on day 20 for determination of GE and lipid digestibility. In experiment 2, 56 barrows (BW 9.16 ± 1.56 kg) were placed into individual metabolism crates for assessment of GE, lipid, and N digestibility and N retention. Urinary lactulose to mannitol ratio was assessed to evaluate in vivo small intestinal integrity, and urine and plasma were collected to analyze for markers of oxidative stress. Pigs were subsequently euthanized to obtain liver weights and analyze the liver for markers of oxidative stress. In experiment 1, pigs fed the SO thermally processed at 90 °C had reduced ADG (P = 0.01) and ADFI (P = 0.04) compared to pigs fed the other SO treatment groups, with no differences noted among pigs fed the 22.5 °C, 45 °C, and 180 °C SO treatments. No effects of feeding thermally processing SO on dietary GE or lipid digestibility (P > 0.10) were noted in either experiment. In experiment 2, there was no dietary effect of feeding peroxidized SO on the DE:ME ratio, N digestibility, or N retained as a percent of N digested, on the urinary ratio of lactulose to mannitol, on serum, urinary, or liver thiobarbituric acid reactive substances, on plasma protein carbonyls, or on urinary or liver 8-OH-2dG (P > 0.10). In experiment 2, pigs fed the SO thermally processed at 90 °C had the greatest isoprostane concentrations in the serum (P ≤ 0.01) and urine (P ≤ 0.05) compared to pigs fed the unprocessed SO. These results indicate that the change in fatty acid composition and/or the presence of lipid peroxidation products in peroxidized SO may reduce ADG and ADFI in nursery pigs, but appears to have no impact on GE, lipid, or N digestibility, or gut permeability. These data suggest that the presence of lipid peroxidation products may affect certain markers of oxidative stress.

Effects of temperature on the whole body fatty acid composition and histological changes of the gills in blue swimmer crabs, Portunus pelagicus

As water temperatures rise due to the effects of climate change, the effects of temperature on the physiological processes of aquaculture species must be studied. This study evaluates the effects of different water temperatures on the fatty acid (FA) composition and histological development of the gills in the blue swimmer crab, Portunus pelagicus. Three levels of water temperature (24 °C, 28 °C, and 32 °C) were used to determine their effects on the first 119 days of the crabs’ development after C8 stage in a recirculating aquaculture system. The study showed that the FA analysis in crabs in water with a temperature of 28 °C showed greater FA composition in their whole body compositions than in crabs kept at 32 °C. The results of the histological gill analysis showed that the number of hemocytes in the anterior gills of the crabs increased proportionately with the increases in temperature. In summary, temperature affects the Omega-3 and omega-6 concentrations and the histological conditions of the structure of the gills of the P. pelagicus.

Fatty acid synthesis by Chlamydomonas reinhardtii in phosphorus limitation.

The importance of crucial nutrient factors like Phosphate (P) and their limited availability leads to variable fluctuations in fatty acid and phospholipid synthesis in the green alga. These fatty acids and phospholipids are an imperative byproduct of alga which used in biofuel production. The production of phospholipids in alga might be naturally enhanced by the optimized supplied by specific essential nutrient like Phosphate. In this study, green alga Chlamydomonas reinhardtii was cultivated in phosphate stress condition to obtain maximum phospholipids. In the stress condition, the organism exhibited variable changes in chlorophyll, fatty acid, and phospholipid compositions. These parameters analyzed by biomass, X-ray, GC, and TLC. Remarkably, saturated fatty acids, monounsaturated, and di-unsaturated fatty acids amounts, increases, while polyunsaturated fatty acids to decrease markedly. The maximum fatty acid content observed at 0.4 mgl-1 P content in growing media. A broad peak area of 56% of hexadecanoic acid (C 16:0) and followed by 28.8% linolenic (C18:3) was observed in GC analysis. These results indicate the essential fatty acid accumulation maximized at particular phosphate concentration in growing media. This necessary and essential fatty acid production from green algae in a sustainable manner is an inexpensive and excellent way for commercialization and biofuel production.

Ганглиозиды мозга и их функции как природных адаптогенов

In this review some aspects of investigation of vertebrate brain lipids made under the guidance of academician E.M.Kreps and then by his collaborators are characterized using as an example the studies of brain gangliosides. In brain gangliosides and individual phospholipids of cold-water stenothermal teleost fishes higher content of polyenoic and monoenoic fatty acids was revealed than in the brain gangliosides and individual phospholipids of warm-water stenothermal teleosts. The changes in fatty acid composition of lipids during adaptation of fishes to living in cold water and at great water depth are directed to the maintenance of the optimal degree of brain cell membrane fluidity and microheterogeneity. The results of cluster analysis of the data on composition and structure of carbohydrate component of brain gangliosides of various ectothermic vertebrates were used to create a dendrogram. This dendrogram was found to correspond appreciably to the tree of classical taxonomy of vertebrates. The changes in molecular organization of brain gangliosides in the course of evolution of vertebrates are suggested to contribute to differentiation of brain and complication of its functions in phylogenesis. The main mammalian brain gangliosides (GM1, GD1a, GD1b и GT1b) protect nerve cells against the action of excitatory amino acids, hydrogen peroxide, amyloid β-peptide and other toxins, their protective effect depending on activation of Trk receptor tyrosine kinase and downstream protein kinases (Akt, ERK1/2, protein kinase C). Another mechanism of protection is used by GM1 and GD1a gangiosides against bacterial lipopolysaccharide (LPS)-induced toxicity. It appears to be due to changes of lipid composition of plasma membrane rafts of nerve cells due to exogenous ganglioside incorporation, which prevents LPS receptors TLR4 translocation to them. Using Morris water test intranasal administration of gangliosides was shown to prevent the impairment of spatial memory in rats with 2-nd type diabetes mellitus. Intranasal administration of gangliosides was used for the first time, its high efficiency was shown.