Modification Of Fatty Acid Composition Research Articles

Elucidating the functional role of human ABHD16B lipase in regulating triacylglycerol mobilization and membrane lipid synthesis in Saccharomyces cerevisiae

Lipids are essential biological macromolecules that play a pivotal role in various physiological processes and cellular homeostasis. ABHD16B, a member of the α/β-hydrolase domain (ABHD) superfamily protein, has emerged as a potential key regulator in lipid metabolism. However, the precise role of human ABHD16B in lipid metabolism remains unclear. In this study, we reported the overexpression of ABHD16B in Saccharomyces cerevisiae to determine its physiological relevance in lipid metabolism. Through in vivo [14C]acetate labeling experiments, we observed that overexpression of ABHD16B causes a decrease in cellular triacylglycerol (TAG) levels and a concurrent increase in phospholipid synthesis in wild-type cells. Mass spectrometry (LC–MS/MS) analysis further corroborated these findings, showing a significant decrease in TAGs with a carbon chain length of 48 and an increase in major phospholipid species, specifically 34:2, upon overexpression of ABHD16B. Confocal microscopy analysis revealed a reduction in the number of lipid droplets in strains overexpressing ABHD16B, consistent with the observed decrease in neutral lipids. Additionally, qRT-PCR analysis indicated a high phospholipid synthetic activity of ABHD16B and a potential decrease in TAG levels in wild-type yeast, possibly due to upregulation of endogenous TAG hydrolytic enzymes, as confirmed using 3tglsΔ mutant strain. Furthermore, GC-MS analysis revealed significant modifications in fatty acid composition upon ABHD16B overexpression. Collectively, our results underscore the influence of ABHD16B overexpression on TAG levels, phospholipid synthesis, lipid droplet dynamics, and fatty acid composition. These findings reveal a complex interplay between TAG hydrolysis and phospholipid synthesis, highlighting the critical involvement of ABHD16B in lipid homeostasis and providing further insights into its regulatory function in cellular lipid metabolism.

Modification of Fatty Acid Composition of Escherichia coli by Co-Expression of Fatty Acid Desaturase and Thioesterase from Arabidopsis thaliana.

Fatty acid composition has an important influence on the fluidity of biological membranes, which is a key factor for the survival of Escherichia coli. With the aim to modify fatty acid composition in this experimentally friendly microorganism, the AtFab2 gene, encoding the Arabidopsis thaliana fatty acid desaturase, was expressed separately and jointly with AtFatA, a fatty acid thioesterase of the same plant origin. The expression of ATFab2 desaturase resulted in an enhancement of cis-vaccenic acid (18:1Δ11) contents, while amounts of palmitioleic acid (16:1Δ9) accumulated by E. coli were increased by 130% for the expression of the AtFatA thioesterase. In the final engineered strain co-expressing AtFab2 and AtFatA, the percentage of palmitic acid (16:0), the most abundant saturated fatty acid found in E. coli, was reduced to 29.9% and the ratio of unsaturated fatty acid to saturated fatty acid reached 2:1. Free fatty acids accounted for about 40% of total fatty acid profiles in the recombinant strain expressing both two genes, and the unsaturated fatty acid contents reached nearly 75% in the free fatty acid profiles. The increase of unsaturated fatty acid level might provide some implication for the construction of cold tolerant strains.

Molecular identification and transmission mode of a phytoplasma and its effect on fatty acid composition in Taverniera cuneifolia

Taverniera cuneifolia plants showing shoots proliferation and witches' broom symptoms were observed in Minab, Iran. A study was performed to detect and identify the possible phytoplasma associated with the disease, identify the putative insect vector and possible modification in fatty acid composition of symptomatic plant roots. Sequence analysis revealed that the associated phytoplasma shared 99.92% sequence identity with ‘Candidatus Phytoplasma australasia'-related strains. Successful transmission of phytoplasma by Orosius albicinctus to healthy periwinkle demonstrated its putative vector status. Moreover, analysis of the oil composition of the plant roots revealed an increased rate of fatty acid composition in the infected plants.

Seasonal Variation of Chemical Composition, Fatty Acid Profile, and Sensory Properties of a Mountain Pecorino Cheese.

This study aims to assess the compositional traits and sensory characteristics of a traditional pecorino cheese associated with management and feeding system seasonality. The study was carried out on two mountain dairy farms using an outdoor, pasture-based system from April to October (OutS), and an indoor system (InS) during the rest of the year. Outdoor-produced milk had higher fat content and a tendency for protein and somatic cell count to be higher. The OutS cheeses showed higher dry matter and fat content, higher percentages of unsaturated fatty acids, C18:3, cis-9, trans-11 conjugated linoleic acid, and trans-11 C18:1, and lower percentages of C14:0 and C16:0. These modifications in fatty acid composition determined the reduction of the atherogenic index. The OutS cheeses also displayed higher intensity of almost all sensory attributes, including odor, flavor, taste, and texture descriptors. The outdoor system partly reduced the liking of consumers for pecorino. However, changes in the productive process leading to an increment in the water content and softness of the cheeses (i.e., controlled humidity and temperature during ripening) may increase the overall liking of pasture-based products, thus promoting the consumption of healthier foods.

Stress hormones mediated lipid accumulation and modulation of specific fatty acids in Nannochloropsis oceanica CASA CC201

The aim of this study is to analyze the effect of two plant growth regulators on selective modulation of nutraceutically important fatty acids. Exogenous application of methyl jasmonate (MeJA) promoted microalgal growth compared to control. Treatment with 10 ppm salicylic acid (SA) induced significantly higher lipid production of 475 mg/L (2.2 fold). Interestingly treatment with higher doses of MeJA promoted monounsaturated fatty acid production, particularly oleic acid (C18:1) at early stationary growth phase, while treatment with SA induces essential omega 3 fatty acid production (EPA, C20:5). This significant modification of fatty acid compositions was correlated with the oxidative stress in terms of total reactive oxygen species production and endogenous growth hormone levels. Taken together, the results indicated that treatment with stress associated plant hormones significantly increased high value metabolite accumulation specifically MUFA and PUFA production by modulating stress mechanisms and endogenous growth hormone levels.

Development of a Technology for the Directed Modification of Fatty Acid Composition of Beef in Grass-Fed Feeding

The article presents the results of the influence of studying the formation of a fatty acid profile in cattle meat using forage herbs rich in secondary metabolites (polyphenol oxidase, saponins, tannins and catecholamines) on lipolysis and biohydrogenation in animal rumen. The experiment planning matrix was performed using the Latin square method. The main factor studied was the effect of polyphenol oxidase on biohydrogenation processes in animals. Based on the studies, recommendations are made on the optimal composition of grassland in the pastures of the South of Russia in order to improve the fatty acid composition of beef.

Growth Performance, Carcass Characteristics, Fatty Acid Composition, and Blood Biochemical Parameters of Lamb Fed Diet with the Addition of Lingonberry Leaves and Oak Bark

AbstractThe aim of the study is to determine the effect of natural additives supplemented to the lamb diet on lamb performance, fatty acid (FA) composition of edible parts of lambs, and biochemical plasma indices. The study is carried out on 18 male lambs, allocated to three groups in a randomized complete block design. Control animals (CON) are fed a basic diet, while the experimental lambs additionally receive lingonberry leaves (VVI) or oak bark (QUE) (10 g d−1), as a different source of tannins. Supplementing lambs with the VVI diet decreases fat content in the longissimus dorsi muscle (MLD). The VVI diet decreases monounsaturated fatty acid (MUFA) concentration (including C18:1 cis‐9) in the MLD, increases the proportion of C16:0, C16:1, C17:1, and C22:6 n‐3 in the semitendinosus muscle, as well as increases the n‐6/n‐3 ratio and thrombogenic index in the liver. The addition of QUE to lamb diets decreases C17:1 concentration and increases the content of C18:1 trans‐11 in the MLD. Tannins‐enriched diets increase low density lipoprotein concentrations in the blood plasma. The VVI diet increases the activity of alkaline phosphatase, while QUE supplementation decreases gamma‐glutamyl transferase activity in blood plasma. Modifications of FA composition in lamb tissues may suggest an indirect effect of tannins on FA ruminal biohydrogenation.Practical Applications: The use of VVI and QUE in lamb nutrition as natural resources is of a great interest to scientists. The present study shows that primarily VVI addition to lamb diets affects the quality of meat, due to higher proportion of catechin than QUE. Decreased concentration of fat, as well as increased proportion of C22:6 n‐3 and desirable fatty acids (including MUFA, polyunsaturated fatty acid, C18:0) after VVI supplementation increases health‐promoting properties of lamb meat and is related to humans. However, the presence of biologically active substances (tannins) in the examined additives makes it necessary to further research and discover their full potential in many areas.

Molecular cloning, phylogenetic analysis and functional characterisation of an Elovl7-like elongase from a marine crustacean, the orange mud crab (Scylla olivacea).

The capacity of crustaceans to biosynthesise long-chain polyunsaturated fatty acids has yet to be fully defined, due to the lack of evidence on the functional activities of enzymes involved in desaturation or elongation of fatty acid substrates. We report here the cloning and in vitro functional analysis of an elongase from the orange mud crab, Scylla olivacea. Sequence and phylogenetic analysis placed the elovl close to the vertebrate Elovl1 and Elovl7 clade, which is distinct from the other remaining five Elovl families. The elongase was also clustered together with several elongases from crustaceans and insects. This elongase showed activities towards 16:1n-7, and at lower rate, linoleic acid (18:2n-6) and linolenic acid (18:3n-3). To our knowledge this is the first description of a functional enzyme involved in biosynthesis of long-chained polyunsaturated fatty acids in a crustacean species. Expression of the S. olivacea elovl7-like mRNA was prominent in stomach, intestine and gill tissues, due to the need to regulate the permeability of epithelial tissue through modification of fatty acid compositions. The implication of our findings, in terms of ability of Crustacea phylum to biosynthesise polyunsaturated fatty acids is discussed.

Cold adaptive potential of pine wood nematodes overwintering in plant hosts.

ABSTRACTThe pine wood nematode (PWN; Bursaphelenchus xylophilus) is the causal agent of pine wilt disease, which results in severe ecological and economic losses in coniferous forests. During overwintering, PWNs undergo morphological and physiological changes to adapt to low temperature environments. Here, the physiological changes of the PWN populations sampled in the summer and winter were compared to analyze the role of low temperatures in their response. The PWN overwinters as third-stage dispersal juveniles, which showed significantly greater survival rates than summer populations (propagative forms) at sub-zero temperatures. The major biochemical compounds in the populations were analyzed by gas chromatography. Eight dominant fatty acids, with stearic acid being the most important, were identified from PWN propagative stage and third-stage dispersal stage. Compared with the propagative stage, the dispersal stage showed significant increases in the fatty acid content and the proportion of unsaturated fatty acids. Three carbohydrates, trehalose, glycerol and glucose, were detected in the PWN. Compared with the summer population, the levels of trehalose and glycerol increased significantly, while glucose decreased, in the winter population. The modifications in fatty acid composition and cryoprotectant levels, as elements of its changing physiology, play important roles in the overwintering success of the PWN.

Gibberellin Promotes Cell Growth and Induces Changes in Fatty Acid Biosynthesis and Upregulates Fatty Acid Biosynthetic Genes in Chlorella vulgaris UMT-M1.

Microalgae lipids and oils are potential candidates for renewable biofuels and nutritional inventions. Recent studies from our lab have shown that two plant hormones, auxin and jasmonic acid, influence microalgae growth and fatty acid accumulation. Therefore, in this study, a high oil-producing strain Chlorella vulgaris UMT-M1 was selected for hormonal study using gibberellin (GA). Exogenous GA3 was applied to early stationary culture of C. vulgaris UMT-M1. Results showed that GA3 gradually increases the cell density of C. vulgaris to up to 42% on days after treatment (DAT)-8 and also capable of delaying the algal senescence. However, the increment in cell density did not enhance the total oil production albeit transient modification of fatty acid compositions was observed for saturated (SFA) and polyunsaturated (PUFA) fatty acids. This illustrates that GA3 only promotes cell division and growth but not the oil accumulation. In addition, application of GA3 in culture medium was shown to promote transient increment of palmitic (C16:0) and stearic (C18:0) acids from DAT-4 to DAT-6 and these changes are correlated with the expression of β-ketoacyl ACP synthase I (KAS I) gene.

Selection of a Taxon-Specific Reference Gene for Qualitative and Quantitative PCR Detection of Carthamus tinctorius

Safflower (Carthamus tinctorius) is an emerging model plant for the transgenic modification of fatty acid composition and the production of pharmaceuticals, proteins, or enzymes. Safflower is also a traditional Chinese medicine and is often used as a fake saffron product. Reliable detection of an endogenous reference gene is indispensable for the supervision of genetically modified safflower. Such an endogenous reference gene can also be used to specifically identify safflower ingredient in complex mixtures such as medicine or food. In this study, we identified and validated the CTOS gene as an endogenous reference for safflower. Conventional and real-time polymerase chain reaction (PCR) methods for detecting the CTOS gene sequence showed high interspecies specificity and intra-species stability. The lowest copy number detectable by conventional PCR was 10 haploid copies. The limit of detection and limit of quantification for the real-time PCR assay were estimated to be five and 40 haploid genome copies, respectively. Standard curves established for the real-time PCR assay exhibited good linearity (R 2 > 0.99) between the cycle threshold (Ct) values and the initial template copies. The developed conventional and real-time PCR assays were validated in routine analysis of the safflower ingredient in commercial Chinese medicines. In conclusion, the developed quantitative PCR methods were sufficiently specific and sensitive to be used in safflower genomic DNA quantification and safflower ingredient identification.

Lifelong imbalanced LA/ALA intake impairs emotional and cognitive behavior via changes in brain endocannabinoid system

Imbalanced dietary n-3 and n-6 PUFA content has been associated with a number of neurological conditions. Endocannabinoids are n-6 PUFA derivatives, whose brain concentrations are sensitive to modifications of fatty acid composition of the diet and play a central role in the regulation of mood and cognition. As such, the endocannabinoid system appears to be an ideal candidate for mediating the effects of dietary fatty acids on mood and cognition. Lifelong administration of isocaloric α-linolenic acid (ALA)-deficient and -enriched diets induced short-term memory deficits, whereas only dietary ALA enrichment altered emotional reactivity in adult male rats compared with animals fed a standard diet that was balanced in ALA/linoleic acid (LA) ratio. In the prefrontal cortex, both diets reduced 2-AG levels and increased MAG lipase expression, whereas only the enriched diet reduced AEA levels, simultaneously increasing FAAH expression. In the hippocampus, an ALA-enriched diet decreased AEA content and NAPE-PLD expression, and reduced 2-AG content while increasing MAG lipase expression. These findings highlight the importance of a diet balanced in fatty acid content for normal brain functions and to support a link between dietary ALA, the brain endocannabinoid system, and behavior, which indicates that dietary ALA intake is a sufficient condition for altering the endocannabinoid system in brain regions modulating mood and cognition.

Finishing feeding strategy as an instrument for modification of fatty acid composition of brook char (Salvelinus fontinalis)

This study investigated the possibility of using a finishing feeding strategy and to apply a dilution model for the calculation of the content of fatty acids (FA) in farmed brook char (Salvelinus fontinalis). Four duplicate groups of fish with an initial weight 153.3 ± 4.9 g−1 were kept in a flow-through system for 135 days, during which they more than triplicated their weight. Control groups were fed the same unmodified commercial diet with 100 % fish oil (FO) or with 60 % fish oil and 40 % rapeseed oil (RO) mixture. Two groups were fed by RO diet followed by 45 (RO:45FO) and 90 (RO:90FO) days of FO diet, respectively, at the end of the growing period. The fillet FA composition at the end of the experiment corresponded with the FA composition of the lipid source in the diet for the tested groups. A significant (p < 0.05) impact on FA composition with a decreasing tendency in the representation of n-3 HUFA with a prolonged feeding period with the RO diet was observed. The application of a dilution model enabling the prediction of the content of a given fatty acid in a given time was successfully performed.

Characterization of SPARC physiological function by immune-inhibited grouper

Secreted protein acidic and rich in cysteine (SPARC) involves antigen-specific immune responses of dendritic cell migration. It is also a matricellular protein that correlates with adipocyte hyperplasia and hypertrophy and regulates adipogenesis and lipid accumulation in muscle. However, the physiological function of fish SPARC remains unclear. Therefore, the objective of this study is to characterize SPARC physiological function by immune-inhibited groupers. The immune-inhibition was performed by triggering the adaptive immune response against SPARC in orange-spotted grouper. After the treatment, the adaptive immune response was represented by the value of anti-SPARC titer. The SPARC-inhibited grouper showed higher value than control in various parameters including body weight, body weight without viscera and fillet weight. In addition, the fatty acid composition of muscle SPARC-inhibited grouper is similar to control groupers. Although none of effect shown on total serum cholesterol, the serum triglyceride significant increased. The adipocyte density and lipid accumulation increased in muscle tissue. Furthermore, it is interesting that SPARC mRNA expression in muscle tissue was increased while the protein expression of SPARC decreased. In conclusion, the grouper SPARC regulates the adipogenesis and lipid accumulation without modification of fatty acid composition and then further affects the growth of the grouper. These results provide a new model system by immuneinhibition technology for physiological function analysis in fish.

Role of bioactive fatty acids in nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD) is characterized by fat deposition in hepatocytes, and a strong association with nutritional factors. Dietary fatty acids are classified according to their biochemical properties, which confer their bioactive roles. Monounsaturated fatty acids have a dual role in various human and murine models. In contrast, polyunsaturated fatty acids exhibit antiobesity, anti steatosic and anti-inflammatory effects. The combination of these forms of fatty acids—according to dietary type, daily intake and the proportion of n-6 to n-3 fats—can compromise hepatic lipid metabolism. A chemosensory rather than a nutritional role makes bioactive fatty acids possible biomarkers for NAFLD. Bioactive fatty acids provide health benefits through modification of fatty acid composition and modulating the activity of liver cells during liver fibrosis. More and better evidence is necessary to elucidate the role of bioactive fatty acids in nutritional and clinical treatment strategies for patients with NAFLD.

Effects on Physicochemical Characteristics of Yoghurt and Ice Cream with Fatty Acid Modification and Cholesterol Removal

This study investigated the effect of fatty acid modification and cholesterol removal on physico-chemical characteristics of yoghurt and ice cream. Fatty acid profile of milk fat was modified by feeding calcium salts of soybean oil fatty acids to cows and cholesterol was removed by b-cyclodextrin. b-cyclodextrin removed 76% and 60% cholesterol from yoghurt and ice cream. Modification of fatty acid composition did not have a significant effect on a-tocopherol content; while b-cyclodextrin treated milk had substantially lower a-tocopherol content. The concentration of a-tocopherol in control and b-cyclodextrin treated yoghurt was 45.62, 32.73 mg/g and 210.34, 185.56 mg/g for ice cream, respectively. Fatty acid modification and cholesterol removal significantly decreased the overrun in ice cream (P&lt;0.05), with no effect on sensory characteristics of yoghurt and ice cream. These results evidenced that milk with higher content of unsaturated fatty acids and low cholesterol can be used in the formulation of yoghurt and ice cream with improved health benefits and suitable sensory features.

Elucidating the role of jasmonic acid in oil accumulation, fatty acid composition and gene expression in Chlorella vulgaris (Trebouxiophyceae) during early stationary growth phase

Manipulation of microalgae cultivation is an important approach as the growth conditions will determine the quality and compositions of lipids produced by the cells. This study attempts at maximizing the production of lipids in Chlorella vulgaris (Trebouxiophyceae) through introduction of the plant hormone jasmonic acid (JA). Exogenous application of JA at early stationary growth phase promoted microalgal growth with increment of up to 51% of cell density relative to the control. JA also transiently increased the total oil production of microalgal cells by 54%. Interestingly, this increment also induced significantly higher production of saturated (SFA) and monounsaturated (MUFA) without compensating the production of polyunsaturated fatty acid (PUFA). Further analysis of fatty acid compositions showed that JA stimulated the production of C16:0 (palmitic acid), C18:0 (stearic acid) and C18:1 (oleic acid) at early stationary growth phase whilst C18:3 n-3 (α-linolenic acid) at later stationary growth phase. This transient modification of fatty acid compositions was correlated with the fatty acid biosynthetic gene expression as quantified by real-time PCR. Taken together, our results indicated that JA significantly increased microalgal lipid accumulation and could be utilized in cultivation to facilitate commercial mass production of microalgae lipids.

Dietary combination of sucrose and linoleic acid causes skeletal muscle metabolic abnormalities in Zucker fatty rats through specific modification of fatty acid composition.

A dietary combination of sucrose and linoleic acid strongly contributes to the development of metabolic disorders in Zucker fatty rats. However, the underlying mechanisms of the metabolic disorders are poorly understood. We hypothesized that the metabolic disorders were triggered at a stage earlier than the 8 weeks we had previously reported. In this study, we investigated early molecular events induced by the sucrose and linoleic acid diet in Zucker fatty rats by comparison with other combinations of carbohydrate (sucrose or palatinose) and fat (linoleic acid or oleic acid). Skeletal muscle arachidonic acid levels were significantly increased in the sucrose and linoleic acid group compared to the other dietary groups at 4 weeks, while there were no obvious differences in the metabolic phenotype between the groups. Expression of genes related to arachidonic acid synthesis was induced in skeletal muscle but not in liver and adipose tissue in sucrose and linoleic acid group rats. In addition, the sucrose and linoleic acid group exhibited a rapid induction in endoplasmic reticulum stress and abnormal lipid metabolism in skeletal muscle. We concluded that the dietary combination of sucrose and linoleic acid primarily induces metabolic disorders in skeletal muscle through increases in arachidonic acid and endoplasmic reticulum stress, in advance of systemic metabolic disorders.

Fatty acid composition remains stable across trophic levels in a gall wasp community

AbstractAcquiring sufficient nutrients is particularly important for insects that are unable to synthesize certain nutrient types de novo, as is the case for numerous parasitoid species that do not synthesize lipids. The lipid reserves of parasitoids are acquired from a single host during larval development. This imposes constraints on the quantity and quality of available lipids. In the present study, the lipid dynamics throughout the trophic cascade are investigated by measuring lipogenic ability, modifications in fatty acid composition and host exploitation efficiency in species at different trophic positions within the community of parasitoids associated with the gall wasp Diplolepis rosae L. (Hymenoptera: Cynipidae). The results obtained show that lipid levels remain stable or decline after feeding in all species, indicating that none of the wasps synthesize lipids. Fatty acid composition is highly similar between the gall wasp, parasitoid and hyperparasitoid species, with the exception of the parasitoid Orthopelma mediator Thunberg (Hymenoptera: Ichneumonidae). The divergence of fatty acid composition in O. mediator suggests that this species is able to modify its fatty acid composition after the consumption of host lipids. The efficiency of exploitation of host resource, in terms of dry body mass acquired, varies among the species (41–70%), although it is high overall compared with the efficiencies reported in other animals. Hence, for parasitoid wasps that lack lipid synthesis capabilities, the efficiency of host exploitation is high and fatty acids are consumed directly from the host without modification, leading to stable fatty acid compositions throughout the trophic cascade.

Effect of long-term salinity on cellular antioxidants, compatible solute and fatty acid profile of Sweet Annie (Artemisia annua L.)

Impact of long-term salinity and subsequent oxidative stress was studied on cellular antioxidants, proline accumulation and lipid profile of Artemisia annua L. (Sweet Annie or Qinghao) which yields artemisinin (Qinghaosu), effective against cerebral malaria-causing strains of Plasmodium falciparum. Under salinity (0.0-160 mM NaCl), in A. annua, proline accumulation, contents of ascorbate and glutathione and activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR) and catalase (CAT) increased, but the contents of reduced forms of glutathione (GSH) and ascorbate declined. The fatty-acid profiling revealed a major salinity-induced shift towards long-chain and mono-saturated fatty acids. Myristic acid (14:0), palmitoleic acid (16:1), linoleic acid (18:2) and erucic acid (22:1) increased by 141%, 186%, 34% and 908%, respectively, in comparison with the control. Contents of oleic acid (18:1), linolenic acid (18:3), arachidonic acid (22:0) and lignoceric acid (24:0) decreased by 50%, 17%, 44% and 78%, respectively. Thus, in A. annua, salinity declines ascorbate and GSH contents. However, increased levels of proline and total glutathione (GSH+GSSG), and activities of antioxidant enzymes might provide a certain level of tolerance. Modification in fatty-acid composition might be a membrane adaptation to long-term salinity and oxidative stress.