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In this work, seeds from selected Mertensia species were analyzed for γ-linolenic acid-rich oils and minor functional compounds. Fatty acids (FA) were analyzed by GC-FID; tocopherols, sterols, squalene, and phenolics compounds by HPLC-DAD, and the structures of the latter were confirmed by LC-MS. M. maritima spp. asiatica and M. sibirica showed the highest amounts of γ-linolenic acid (22.8 and 18.7%, respectively) and total FA (15.9 and 10.9 g/100 g seeds, respectively). M. sibirica had the greatest levels of sterols, phenolics and tocopherols (244.8, 243.9 and 66.3 mg/100 g, respectively), in which stigmasterol, rosmarinic acid and α-tocopherol (237.7, 180.1 and 53.6 mg/100 g, respectively) were the most abundant components. M. maritima spp. asiatica and M. arizonica showed the highest amounts of squalene (2.5 and 1.1 mg /100 g seeds). Mertensia species constitute a new source of GLA-rich oils, suitable to be marketed by the pharmaceutical and food industries., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Polyunsaturated fatty acids (PUFAs) are closely related to various physiological conditions. In several age-related diseases including Alzheimer's disease (AD) altered PUFAs metabolism has been reported. However, the mechanism behind PUFAs impairment and AD developpement remains unclear. In humans, PUFAs biosynthesis requires delta-5 desaturase (D5D), delta-6 desaturase (D6D) and elongase 2 activities; which are encoded by fatty acid desaturase 1 (FADS1), fatty acid desaturase 2 (FADS2), and elongation of very-long-chain fatty acids-like 2 (ELOVL2) genes, respectively. In the present work, we aim to assess whether genetic variants in FADS1, FADS2 and ELOVL2 genes influence plasma and erythrocyte PUFA composition and AD risk. A case-control study was carried out in 113 AD patients and 161 healthy controls.Rs174556, rs174617, and rs3756963 of FADS1, FADS2, and ELOVL2 genes, respectively were genotyped using PCR-RFLP. PUFA levels were quantified using Gas Chromatography. Genotype distributions of rs174556 (FADS1) and rs3756963 (ELOVL2) were different between case and control groups. The genotype TT of rs174556 and rs3756963 single nucleotide polymorphism (SNP) increases significantly the risk of AD in our population. PUFA analysis showed higher plasma and erythrocyte arachidonic acid (AA) level in patients with AD, whereas only plasma docosahexaenoic acid (DHA) was significantly decreased in AD patients. The indexes AA/Dihomo-gamma-linolenic acid (DGLA) and C24:4n-6/Adrenic acid (AdA) were both higher in the AD group. Interestingly, patients with TT genotype of rs174556 presented higher AA level and AA/DGLA index in both plasma and erythrocyte. In addition, higher AA and AA/DGLA index were observed in erythrocyte of TT genotype ofrs3756963 carrier's patients. Along with, positive correlation between AA/DGLA index, age or Gamma-linolenic acid (GLA)/ Linoleic acid (LA) index was seen in erythrocyte and /or plasma of AD patients. After adjustment for confounding factors, the genotype TT of rs174556, erythrocyte AA and AA/DGLA index were found to be predictive risk factors for AD while plasma DHA was found associated with lower AD risk. Both rs174556 and rs3756963 influence AD risk in the Tunisian population and they are likely associated with high AA level. The combination of the two variants increases further the susceptibility to AD. We suggest that FADS1 and ELOVL2 variants could likely regulate the efficiency of AA biosynthesis which could be at the origin of inflammatory derivate., Competing Interests: Declaration of Competing Interest All authors have no conflict of interests., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The role of fish oil, primrose oil and their mixture in ameliorating the changes in Alzheimer's like model was evaluated in rats. Primrose oil and primrose/fish oil mixture fatty acids composition was assessed by gas chromatography. The rat experiment consisted of 5 groups; the first fed on balanced diet as control normal (CN); the other four groups treated with intraperitoneal aluminum lactate and consumed dyslipidemic diet; one group served as control Alzheimer's like disease (CA) while the other three groups (test groups) received daily oral dose from primrose oil, fish oil and primrose/fish oil mixture separately for 5 weeks. Results showed primrose oil and primrose/ fish oil mixture to contain gamma linolenic acid as 9.15 and 4.3% of total fatty acids, respectively. Eicosapentaenoic and docosahexaenoic were present as 10.9 and 6.5 %, respectively in the oil mixture. Dyslipidemia and increased erythrocyte sedimentation rate (ESR), plasma butyrylcholinesterase (BChE), brain malondialdehyde (MDA) and NO with decrease in plasma magnesium, brain catalase, reduced glutathione, body weight gain and brain weight were demonstrated in CA compared to CN. Brain histopathology and immuno-histochemistry showed neuronal degeneration and neurofibrillary tangles with elevated myeloperoxidase and nuclear factor-kappa B in CA compared to CN. The tested oils demonstrated neuro-protection reflected in the variable significant improvement of biochemical parameters, immuno-histochemistry and brain histopathology. Primrose/fish oil mixture was superior in reducing ESR, brain MDA, plasma activity of BChE and brain histopathological changes along with elevating plasma magnesium. Primrose/fish oil mixture and fish oil were more promising in improving plasma high density lipoprotein cholesterol (HDL-C) than primrose. Fish oil was the most efficient in improving plasma total cholesterol (T-C), low density lipoprotein cholesterol and T-C /HDL-C. Primrose/fish oil mixture and primrose oil were superior in elevating brain catalase compared to fish oil. Other parameters were equally improved by the different oil treatments. Primrose oil, fish oil and their mixture reduced the progression of Alzheimer's disease in rats with superiority to primrose/fish oil mixture.

High-fat and high-sucrose diet (HFHSD)-induced obesity leads to oxidative stress and chronic inflammatory status. However, little is known about the beneficial effects of total lipids extracted from Spirulina . Hence, in the present study, Spirulina lipids were extracted with chloroform/methanol (SLC) or ethanol (SLE) and then their effects on oxidative stress and inflammation in the mice fed a HFHSD were investigated. The results show that the major lipid classes and fatty acid profiles of SLC and SLE were almost similar, but the gamma-linolenic acid (GLA) and carotenoid contents in SLE was a little higher than that in SLC. Dietary 4% SLC or SLE for 12 weeks effectively decreased the hepatic lipid hydroperoxide levels as well as increased the activities and mRNA levels of antioxidant enzymes in the mice fed a HFHSD. In addition, supplementation with SLC and SLE also markedly decreased the levels of serum pro-inflammatory cytokines and the mRNA expression of pro-inflammatory cytokines in the liver and epididymal white adipose tissue of mice fed a HFHSD, and the effects of SLC and SLE were comparable. These findings confirm for the first time that dietary Spirulina lipids could alleviate HFHSD-induced oxidative stress and inflammation.

Fifty Ribes species and R. nigrum-based cultivars from eight Ribes sections were surveyed for γ-linolenic acid (GLA, 18:3, n-6)- and stearidonic acid (SDA, 18:4, n-3)-rich oils. R. pallidiflorum, R. glabellum and R. pubescens seed oils contain noticeable GLA amounts: 13.3, 11.8, and 11.9% of total fatty acids (FA), respectively. However, the highest GLA contents were found in the seed oils of several blackcurrant cultivars, highlining Ribes 'Myuryucheene' with 20.2% GLA of total FA. Principal Component Analysis showed that similarities in FA profiles allow grouping species as botanical criteria for Ribes sections do. The main GLA-taxa detected in this study correspond to blackcurrant cultivars, all of them native to Siberia. Considering that such cultivars are notable fruit-producers, its cultivation in Siberia besides producing fruits in very difficult agronomic areas, could produce a valuable by-product, i.e. the seeds, which will add economic value to agricultural systems if devoted to GLA-rich oils extraction., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

This work focused on physicochemical property assaying, fatty acid composition, triacylglycerol (TAG) profiles, and unsaponifiable matters composition of the Chinese evening primrose oil. The cold press oil possessed very low acid value and peroxide value, and relatively high iodine value. Fatty acid composition results indicated that this oil was especially high in linoleic acid and linolenic acid. Characterization of TAG composition was achieved by a two-dimensional HPLC coupling of nonaqueous reverse-phase and silver ion HPLC with atmospheric pressure chemical ionization MS method. There was a total of 38 TAGs including 27 regioisomers which had been determined. Unsaponifiable matters composition results revealed that this oil possessed a number of phytosterols, in which β-sitosterol and stigmasterol were most predominant.

This study aimed at evaluating the polycyclic aromatic hydrocarbons (PAHs) contamination of commercial vegetable oils and examined the identity through the fatty acids profiles. Coconut, safflower, evening primrose, and linseed oils marketed in São Paulo (Brazil) were investigated totaling 69 samples. Four PAHs, benzo[a]anthracene (BaA), chrysene (Chr), benzo[b]fluoranthene (BbF), and benzo[a]pyrene (BaP), were detected in 96% of the samples at individual levels ranging from not detected to 14.99 μg kg -1 . Chrysene was the abundant hydrocarbon found among all types of oils, with the highest median values. The results of the fatty acid profiles revealed that 43% showed different profiles according to the ones on their labels, with a higher incidence of adulteration of evening primrose oils. The maximum tolerable limits by European Regulation No. 835/2011 were exceeded for BaP in 12%, and for total 4 PAHs in 28%, with a greater contribution of adulterated samples., (Copyright © 2017. Published by Elsevier Ltd.)

Mucor circinelloides is one of few oleaginous fungi that produces a useful oil rich in γ-linolenic acid, but it usually only produces <25% total lipid. Nevertheless, we isolated a new strain WJ11 that can produce up to 36% lipid of cell dry weight. In this study, we have systematically analyzed the global changes in protein levels between the high lipid-producing strain WJ11 and the low lipid-producing strain CBS 277.49 (15%, lipid/cell dry weight) at lipid accumulation phase through comparative proteome analysis. Proteome analysis demonstrated that the branched-chain amino acid and lysine metabolism, glycolytic pathway, and pentose phosphate pathway in WJ11 were up-regulated, while the activities of tricarboxylic acid cycle and branch point enzyme for synthesis of isoprenoids were retarded compared with CBS 277.49. The coordinated regulation at proteome level indicate that more acetyl-CoA and NADPH are provided for fatty acid biosynthesis in WJ11 compared with CBS 277.49.

Objective: The aim of this study was to examine differences in fatty acid concentrations in colostrum of women with and without gestational diabetes mellitus (GDM). The effect of GDM on fatty acid composition of colostrum is not fully understood, although rates of GDM are increasing globally., Methods: A prospective case-control study was conducted of postpartum women with and without GDM. Gas chromatographic analysis was conducted to examine differences in colostral fatty acids of the colostrum samples of 29 women with and 34 without GDM., Results: Analyses of the fatty acid composition revealed significantly higher concentrations of four essential ω-6 polyunsaturated fatty acids-γ-linolenic, eicosatrienoic, arachidonic, and docosatetraenoic-in the colostrum of GDM women compared with non-GDM women. Timing of collection influenced saturated medium chain fatty acid and monounsaturated fatty acid levels., Conclusions: Differences in concentrations of ω-6 fatty acids but not in dietary linoleic fatty acid or ω-3 fatty acids suggest that altered concentrations are attributed to changes in specific endogenous metabolic pathways. Implications of higher concentrations of ω-6 fatty acids in the colostrum of women with GDM have yet to be determined. Timing of colostrum collection is critical in determining colostral fatty acid and metabolite concentrations., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The aim of this work was to establish the richness in γ-linolenic acid (GLA, 18:3n6) and stearidonic acid (SDA, 18:4n3) of several Sardinian Boraginaceae species. To this end, seeds of selected species were collected from their natural habitats and analysed. The highest GLA contents were found in the seed oils of two endemic Borago taxa, i.e. B. morisiana (24.4 and 24.6% GLA of total fatty acids for samples from San Pietro Island and Sardinia Island, respectively), and 22.9% GLA for B. pygmaea. Both Borago species contained more GLA than B. officinalis collected in the same ecosystems. SDA was found in significant amounts in Echium plantagineum seed oil from the Lattias Mountains (15% SDA of total fatty acids). It is notable that both Borago GLA-rich species are under threat of extinction, thus revealing the importance of the preservation of the natural Sardinian ecosystems for endangered species and human health., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Structured lipids (SLs) containing palmitic, docosahexaenoic (DHA), and gamma-linolenic (GLA) acids were produced using refined olive oil, tripalmitin, and ethyl esters of DHA single cell oil and GLA ethyl esters. Immobilized Lipozyme TL IM lipase was used as the biocatalyst. The SLs were characterized for fatty acid profile, triacylglycerol (TAG) molecular species, solid fat content, oxidative stability index, and melting and crystallization profiles and compared to physical blend of substrates, extracted fat from commercial infant formula (IFF), and milk fat. 49.28 mol% of palmitic acid was found at the sn-2 position of SL TAG and total DHA and GLA composition were 0.73 and 5.00 mol%, respectively. The total oleic acid content was 36.13 mol% which was very close to the 30.49% present in commercial IFF. Comparable solid fat content profiles were also found between SLs and IFF. The SLs produced have potential for use in infant formulas., (© 2015 Institute of Food Technologists®)

The cultivation of four industrial hemp cultivars (Felina 32, Chamaeleon, Uso31, and Finola) was investigated for oil production in the north-east of Italy along two years. The oils of all cultivars resulted in rich amount of linoleic acid (ω-6) and α-linolenic acid (ω-3). Felina 32 and Chamaeleon oils exhibited the highest amount of linoleic acid (59%) and α-linolenic acid (18%). Finola and Uso31 oils resulted in the richest of γ-linolenic acid (5-6%). All hempseed oils presented high oxidation stability and an acceptable initial quality. It is suggested that these oils can be used to produce EFA dietary supplements high in ω-6 and ω-3 of vegetal origin.

The study evaluated the effect of Spirulina and Thyme dietary supplementation on rabbit meat quality, nutrient true retention and protection against oxidative stress. Rabbits in the control group (C-C) received a non-supplemented pellet throughout the experiment (5-11weeks of age). In the other groups, the pellet contained 5% Spirulina (S), 3% Thyme (T), or both (ST) for either the entire (groups S-S, T-T, ST-ST) or only the final part of the growing period (8-11weeks: groups C-S, C-T, C-ST). Spirulina supplementation increased the γ-linolenic acid content of rabbit meat, whereas Thyme improved the oxidative stability of raw and freeze-dried meat., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Introduction: Atopic dermatitis (AD) has been related to a deficiency of delta-6-desaturase, an enzyme responsible for the conversion of linoleic acid to gamma-linolenic acid (GLA). Evening primrose oil (EPO) contains high amounts of GLA. Therefore, this study investigated whether EPO supplementation results in an increase in plasma GLA and its metabolite dihomo-gamma-linolenic acid (DGLA) correlating with clinical improvement of AD, assessed by the SCORing Atopic Dermatitis (SCORAD) index., Methods: The open study included 21 patients with AD. EPO (4-6 g) was administered daily for 12 weeks. Before treatment, and 4 and 12 weeks after initiation of EPO supplementation, objective SCORAD was assessed and plasma concentrations of GLA and DGLA were determined by gas chromatography., Results: A significant increase in plasma GLA and DGLA levels and a decrease in the objective SCORAD were observed 4 and 12 weeks after initiation of EPO treatment. In the per-protocol population (n = 14), a significant inverse correlation between the changes in plasma GLA levels and SCORAD was found (P = 0.008)., Conclusion: The clinical disease activity under EPO treatment correlates with the individual increase in plasma GLA levels. Thus, the results of this pilot study indicate that an increase in plasma GLA might be used as predictive parameter for responsiveness of AD to EPO therapy.

This study was conducted to examine the chemical composition and antioxidant activity of the essential oils (EOs) of Borago officinalis stem during its flowering stage. The EO composition was characterised by high proportions of E,E-decadienal, the main compound of monoterpene hydrocarbon class, with values varying from 47.08% to 55.28% in two Tunisian regions. The region of Korba exhibited the highest scavenging activity (2.05 mg/mL) by comparison with Beja region. In all tests, the fructification stage showed the best antioxidant activity of all flowering stages.

Recently, steps have been taken to further developments toward increasing gamma-linolenic acid (GLA) concentration and lowering costs in plant seed oils using transgenic technology. Through identification and expression of a fungal delta-6 desaturase gene in the high linoleic acid safflower plant, the seeds from this genetic transformation produce oil with >40% GLA (high GLA safflower oil (HGSO)). The aim of the study was to compare the effects of feeding HGSO to a generally recognized as safe source of GLA, borage oil, in a 90 day safety study in rats. Weanling male and female Sprague-Dawley rats were fed a semi-synthetic, fat free, pelleted diet (AIN93G) supplemented with a 10% (wt/wt) oil blend containing HGSO or borage oil, with equivalent GLA levels. Results demonstrated that feeding diets containing HGSO or borage oil for 90 days had similar biologic effects with regard to growth characteristics, body composition, behavior, organ weight and histology, and parameters of hematology and serum biochemistries in both sexes. Metabolism of the primary n-6 fatty acids in plasma and organ phospholipids was similar, despite minor changes in females. We conclude that HGSO is biologically equivalent to borage oil and provides a safe alternative source of GLA in the diet., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Reversed phase liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (RP-HPLC/APCI-MS) was used for direct analysis of triacylglycerols (TAGs) from different strains of the cyanobacteria Mastigocladus laminosus, Tolypothrix cf. tenuis and Tolypothrix distorta. This technique enabled us to identify and quantify the specific molecular species of TAGs directly from lipid extracts of the cyanobacteria. The regioisomeric series of TAGs having α-linolenic and γ-linolenic and also oleic and cis-vaccenic acids were separated by RP-HPLC and identified by APCI-MS. M. laminosus produced only a few molecular species of TAGs, including both isomers of octadecenoic (oleic and vaccenic) acid, while T. distorta contained tens of molecular species of TAGs having FAs with up to four double bonds (stearidonic acid and including also its positional isomer, i.e. 3,6,9,12-octadecatetraenoic acid) and both positional isomers (α and γ) of linolenic acids. Individual strains of both cyanobacteria exhibited different contents of polyunsaturated fatty acids (Tolypothrix sp.) and different distribution of positional isomers of monoenoic fatty acids in TAGs (M. laminosus)., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

γ-Linolenic acid (GLA) has been used as a general nutraceutical for pharmacologic applications, particularly in the treatment of skin conditions such as eczema. Four transgenic soybean lines that produce GLA at high yields (4.21% of total fatty acids, up to 1002-fold) were generated through the stable insertion of the Delta-6-fatty acid desaturase gene isolated from Borago officinalis into the genome of a conventional soybean cultivar. As part of the safety assessment of genetically engineered crops, the transgenic soybean seeds were compared with their parental soybean seeds (nontransgenic) by applying the principle of substantial equivalence. Compositional analyses were conducted by measuring the fatty acids, proximate analysis (moisture, crude protein, crude fat, carbohydrates, TDF, and ash contents), amino acids, lectins, and trypsin inhibitor activity. The present results showed that the specific transgenic cultivar studied was similar to the conventional control.

Unlabelled: In the present study, fatty acids and essential oils of the flower of borage (Borago officinalis L.) were obtained by supercritical carbon dioxide fluid extraction under different conditions. The extracts obtained were compared to oils of borage flower oil isolated by hydrodistillation. The obtained oils were analyzed by gas chromatography mass spectrometry. The compounds were identified according to their retention indices and mass spectra. The experimental parameters of supercritical fluid extraction (SFE) were optimized using a central composite design after a full factorial experimental design. Extraction yields based on SFE varied in the range of 0.02% to 1.96% (w/w), and the oil yield based on the hydrodistillation was 0.05% (v/w). The optimum conditions of SFE were obtained at a pressure of 350 atm, a temperature of 65 °C, a methanol modifier volume of 100 μL, and static and dynamic extraction time of 10 min. Main components of the extracts under optimum SFE conditions were palmitic acid, linoleic acid, γ-linolenic acid, and oleic acid. The results indicated that by using the suitable extraction conditions, SFE is more effective than the conventional hydrodistillation method in the extraction of fatty acids and the preservation of its quality., Practical Application: SFE is a good technique for the extraction of oils from plants. The extraction yields by SFE are more than the conventional method. SFE is used on a large scale for production of essential oils and pharmaceutical products from plants., (© 2011 Institute of Food Technologists®)

A novel expression system was established in the oleaginous yeast, Lipomyces kononenkoae. The expression vector pLK-rhPHG of L. kononenkoae was constructed and using the hygromycin phosphotransferase gene and green fluorescent protein gene as reporter genes. A delta 6-fatty acid desaturase gene (D6DM) from Cunninghamella echinulata MIAN6 was then expressed in this strain. The recombinant strain accumulated about 1.2% γ-linolenic acid in the total fatty acids., (© Springer Science+Business Media B.V. 2011)

The open reading frame of the Δ(6)-desaturase gene was isolated from Mortierella alpina W15 and the gene was cloned into a pPIC3.5K vector. The vector was transformed into Pichia pastoris GS115 and expression was induced with methanol. The Δ(6)-desaturase expressed in P. pastoris GS115 catalyzed the conversion of linoleic acid to γ-linolenic acid but not the conversion of α-linolenic acid to octadecatetraenoic acid. The results indicate that the Δ(6)-desaturase gene from M. alpina W15 has substrate specificity in different organisms. Phylogenetic analysis revealed that Δ(6)-desaturase genes can be divided into four monophyletic groups. This work paves the way for further study of the functions of Δ(6)-desaturase in fatty acid metabolism and its three-dimensional structure., (© Springer Science+Business Media B.V. 2011)

Essential fatty acids were extracted from Echium amoenum (Boraginaceae) seed oil via supercritical carbon dioxide and the results were compared with conventional Soxhlet method as the base case of 100% recovery. The response surface methodology was used to optimize the effective extraction parameters. The chemical composition of recovered oil was analyzed by polar and non-polar gas chromatograph-flame ionization detector columns. The experimental results indicated that echium seed contained 25 wt% oil and the maximum extraction oil recovery of 92% was obtained via supercritical CO(2) at optimal operating conditions (43°C, 280 bar, 1.5 mL/min, 25 min static time and 130 min dynamic time). At similar operating conditions, applying 2.5 and 5 mol% ethanol as a modifier enhanced the recovery to 96 and 112%, respectively. The results showed that supercritical fluid extraction is a viable technique for separation of constituents such as γ-linolenic acid (7-8%), palmitic acid (6-7%), stearic acid (3-4%), oleic acid (12-13%), linoleic acid (19-20%), α-linolenic acid (40-41%) and stearidonic acid (8-9%) from Boraginaceae., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Lowered sperm quality associated with reduced superoxide dismutase activity in testis and spermatozoa has been observed in red deer from a mined area in South-central Spain. Here we present fatty acid profiles for testis and spermatozoa of deer from this mined area (n=29) and a control area (n=33). Despite elevated Pb in liver and bone of red deer from this area, concentrations in testis and sperm were not significantly higher than in control areas; however, Cu in testis was lower in mined areas. Testis from mined areas also contained higher percentages of linoleic acid (18:2n-6) and dihomo-gamma-linolenic acid (20:3n-6), but lower arachidonic acid (20:4n-6). The percentage of 20:4n-6 was also lower in spermatozoa of deer from the mined area. Copper levels in testis correlated positively with the percentage of 20:4n-6. The imbalance in Cu homeostasis caused by metal pollution may have caused the observed effects on deer sperm., (Copyright 2010 Elsevier Inc. All rights reserved.)

Objective: The influence on the urea inclusion compound under different conditions (allocated proportion, time of inclusion, temperature of inclusion) were studied through the orthogonal test, and theoretical reference of urea inclusion process for further optimization wound be offered., Method: The orthogonal experiment was adopted, and microscope was used to observe the shape, aperture size of the urea inclusion compound under different technological parameters, the GC was employed to inspect the purity of GLA., Result: The results indicated that the ratio of fatty acids and urea, inclusion of temperature, time of inclusion had great effect on urea inclusion compound. The three factors and its interactions significantly affected the purity of GLA. The results also showed that the best process was that the ratio of fatty acids and urea was 1 : 3, temperature of inclusion was--15 degrees C, time of inclusion was 24 h., Conclusion: Under the best condition, the purity of GLA reach up to 95.575 9%; and it is feasible to observe the shape and the amount of the urea inclusion compound to reflect and guide the urea inclusion technology.

The consumption of dietary fats have been long associated to chronic diseases such as obesity, diabetes, cancer, arthritis, asthma, and cardiovascular disease; although some controversy still exists in the role of dietary fats in human health, certain fats have demonstrated their positive effect in the modulation of abnormal fatty acid and eicosanoid metabolism, both of them associated to chronic diseases. Among the different fats, some fatty acids can be used as functional ingredients such as alpha-linolenic acid (ALA), arachidonic acid (AA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), gamma-linolenic acid (GLA), stearidonic acid (STA) and conjugated linoleic acid (CLA), among others. The present review is focused on recent developments in FAs analysis, covering sample preparation methods such as extraction, fractionation and derivatization as well as new advances in chromatographic methods such as GC and HPLC. Special attention is paid to trans fatty acids due its increasing interest for the food industry.

The purpose of this study was to compare the susceptibility of the retina and the exorbital lacrimal gland to dietary supplies of long-chain omega-3 (omega3) and omega-6 (omega6) polyunsaturated fatty acids (LC-PUFAs). Male Wistar rats were fed a 5% lipid diet containing: (1) 10% eicosapentaenoic acid (EPA) and 7% docosahexaenoic acid (DHA), or (2) 10% gamma-linolenic acid (GLA), or (3) 10% EPA, 7% DHA and 10% GLA or (4) a balanced diet deprived of EPA, DHA and GLA for 3 months. Lipids were extracted from plasma phospholipids, retina and exorbital lacrimal gland, and fatty acid composition was determined by gas chromatography. Dietary supplementation with EPA and DHA increased omega3 PUFA levels in plasma phospholipids as well as in the retina and the exorbital lacrimal gland. By contrast, GLA supplementation favored omega6 PUFA incorporation, and particularly the incorporation of the end-chain omega6 product, docosapentaenoic acid (DPA), into all tissues. Supplementation with EPA, DHA and GLA increased the levels of DHA, EPA and dihomo-GLA (dGLA), whereas arachidonic acid (AA) was unchanged and DPA decreased in the retina and the lacrimal gland. The ability of both tissues to incorporate PUFAs from blood was evaluated. The results showed that the retina was more selective than the lacrimal gland for EPA. In spite of the different susceptibility of the retina and the lacrimal gland to dietary PUFAs, these results suggest that the concomitant use of dietary omega3 and omega6 PUFAs may be useful in modulating inflammation in both tissues., (Copyright 2009 S. Karger AG, Basel.)

Gamma-linolenic acid (Gla) and oils containing Gla have evident positive effects on a variety of disorders, and therefore, the structure of triacylglycerols (TAGs) containing Gla is of special interest. The regioisomeric structures of TAGs 18:3(n-3)/18:2/18:2 (Ala/L/L) and 18:3(n-6)/18:2/18:2 (Gla/L/L) in blackcurrant seed oil were determined by Ag-HPLC/APCI-MS and Ag-HPLC/ESI-MS/MS techniques. In the latter, silver ion adducts were prepared by adding silver nitrate to the postcolumn flow. A new Ag-HPLC solvent system containing nonchlorinated solvents for the separation of Gla- and Ala-containing TAGs is introduced. Ag-HPLC separation of Ala/L/L and Gla/L/L was sufficient and regioisomers sn-LnLL + sn-LLLn and sn-LLnL (Ln, linolenic acid) could be differentiated well with the MS methods used. No discrimination was made between the sn-1 and sn-3 positions. The results show that the methods used are suitable to discriminate and determine the regioisomeric structure of TAGs. The regioisomeric structure of TAG with the fatty acid combination Gla/L/L in blackcurrant seed oil was considered to be practically random (32.7-37.8% of sn-LGlaL). In the fatty acid combination Ala/L/L, the regioisomeric structure is nonrandom (7.3-12.1% of sn-LAlaL) with Ala preferentially in a primary position. It can be concluded that the positional distribution of Ala and Gla is different in Ln/L/L TAGs of blackcurrant seed oil.

Milk lipids contain several bioactive factors exhibiting antimicrobial activity against bacteria, viruses, and fungi. In the present study, we demonstrate that free fatty acids (FFA) derived from the saponification of bovine whey cream lipids are active in vitro at inhibiting the germination of Candida albicans, a morphological transition associated with pathogenicity. This activity was found to be significantly increased when bovine FFA were enriched in non-straight-chain FFA. At low cell density, this non-straight-chain FFA-enriched fraction was also found to inhibit in a dose-dependant manner the growth of both developmental forms of C. albicans as well as the growth of Aspergillus fumigatus. Using an assay-guided fractionation, the main components responsible for these activities were isolated. On the basis of mass spectroscopic and gas chromatographic analysis, antifungal compounds were identified as capric acid (C10:0), lauroleic acid (C12:1), 11-methyldodecanoic acid (iso-C13:0), myristoleic acid (C14:1n-5), and gamma-linolenic acid (C18:3n-6). The most potent compound was gamma-linolenic acid, with minimal inhibitory concentration values of 5.4 mg/L for C. albicans and 1.3 mg/L for A. fumigatus, in standardized conditions. The results of this study indicate that bovine whey contains bioactive fatty acids exhibiting antifungal activity in vitro against 2 important human fungal pathogens.

Objective: To explore the best technique parameters on preparing evening primrose oil microspheres by spray drying technique., Method: GC and internal standard method were used to determine the content of gamma-linolenic acid methyl esters, the technological parameters were investigated by orthogonal experimental design with the yield and entrapment rate as indexes., Result: The charging rate as 3 mL x min(-1), atomizing pressure as 100 kPa and the temperature of inlet as 105 degrees C were the best technique parameters., Conclusion: Evening primrose oil microspheres accorded with the expecting demand. The main influencing factor is the charging rate. Spray drying is reasonable and practical for preparing evening primrose oil microspheres.

Background: It has been suggested that atopic dermatitis (AD) is associated with impaired delta-6 desaturase activity and the subsequent altered composition of n-6 essential fatty acids (EFAs)., Objective: To investigate whether n-6 EFA deficiency accounts for AD by affecting transepidermal water loss or the immune response., Methods: Serum levels of n-6 EFAs were measured using gas chromatography-mass spectrometry in a well-defined group of 35 children with AD (IgE level >150 U/mL); 35 age-matched children with allergic rhinitis, asthma, or both (IgE level >150 U/mL); and 31 nonatopic controls (IgE level <100 U/mL). Skin barrier function was evaluated by measuring transepidermal water loss and severity of AD by computing the Scoring Atopic Dermatitis (SCORAD) index., Results: Atopic children had higher levels of linoleic acid (LA) and lower levels of its metabolites. Furthermore, gamma-linolenic acid to LA and dihommo-gamma-linolenic acid to LA ratios were significantly reduced in atopic patients. Transepidermal water loss and the SCORAD index were negatively correlated with serum levels of LA metabolites. There was no correlation between the SCORAD index and IgE level (P = .51) or between n-6 EFA concentrations and IgE level (P > .10)., Conclusions: Deficits in n-6 EFAs were correlated with the severity of AD by affecting skin barrier function and cutaneous inflammation. The link between impaired n-6 EFA metabolism and IgE level could not be defined.

Objective: To study the influence of methyl esterification on the ultraviolet absorption of gamma-linolenic acid., Methods: To measure the ultraviolet absorption value of some gamma-linolenic acid product by Ultraviolet Spectrophotometry before and after methyl esterification and to measure the fatty acids formation with gas chromatographic method. Then to do a correlation analysis of the results., Results: The ultraviolet absorption value of gamma-linolenic acid before methyl esterification was very significantly correlated with that after methyl esterification., Conclusion: It is feasible to mesure the ultraviolet absorption value of polyunsaturated fatty acids (such as gamma-linolenic acid) without methyl esterification.

Background: Breastfeeding accounts for a sizable proportion of infant HIV infections. Some fatty acids (FAs) are potent immunomodulators with virucidal activity, and their primary source in breastfed children is breast milk., Objectives: The aims of the study were to examine whether the percentage weight concentration of FAs in breast milk was associated with the risk of mother-to-child transmission (MTCT) of HIV by breastfeeding and with shedding of cell-free virus (CFV) or cell-associated virus (CAV) in breast milk., Design: We conducted a case-control study nested within a cohort of HIV-infected Tanzanian women and children. We matched 59 incident breastfeeding MTCT cases to 59 nontransmitting controls based on the child's age at sample collection. We quantified FAs, CFV, and CAV in a breast milk sample collected before the infant's first positive HIV test., Results: After adjustment for indicators of maternal HIV disease stage, the risk of MTCT was inversely related to 11c,14c-eicosadienoic acid [odds ratio (OR) for quartile 4 compared with quartile 1: 0.21; P for trend = 0.04], arachidonic acid (OR: 0.21; P for trend = 0.03), and dihomo-gamma-linolenic acid (OR: 0.24; P for trend = 0.03); the latter 2 were also linearly, inversely related to virus shedding in breast milk. Lauric acid and pentadecanoic acid were associated with increased MTCT, whereas trans FAs were related to higher CAV and CFV., Conclusion: Increasing concentrations of long-chain n-6 polyunsaturated FAs in breast milk might reduce the risk of MTCT.

While many naturally occurring mixtures of free fatty acids are conveniently analyzed by hyphenated technique of LC-NMR, a complete separation of alpha- and gamma-linolenic acids for their quantitative determination appears impossible at least by the methods of reversed phase HPLC. However, they can be differentiated and quantified from 1H NMR spectra measured in the course of isocratic acetonitrile-chloroform (90:10, with C8 and C18 columns in series) LC-NMR analysis without the need for any derivatization.

Changes in the composition of fatty acids (FA) were determined in lipid extracts isolated from developing ovaries containing ovules and developing seeds of Echium vulgare L. The samples were collected successively over 20 days beginning with the first day after flowering. The contents of the n-6 FA family members, i.e., gamma-linolenic (GLA) (C(18:3)) and linoleic (LA) (C(18:2)) acids changed in a parallel manner and reached the maximum of 13.9% and 24%, respectively, on the 12th day, after which they fell systematically down to 8.6% and 18.2%, respectively, on the 20th day after flowering. Starting with day 13, the content of alpha-linolenic acid (ALA) (C(18:3) n-3) begins to grow intensively, from 24.2% to 39.3% on the 20th day after flowering. The increase in the content of stearidonic acid (SDA) (C(18:4) n-3), up to 10.5% on the 20th day after flowering, occurred steadily as the seeds developed, and was independent of the changes in the content of GLA and LA. The pattern of changes in the content of SDA, GLA, LA and ALA during the development of seeds, and the occurrence of SDA in the seed oil of other plants, demonstrate that the biosynthesis of SDA in the seeds is critically dependent on the presence of ALA. The above condition indicates that SDA biosynthesis in the seeds of Echium vulgare follows the scheme LA --> simultaneous, competitive, action of Delta(6) and Delta(15) desaturases, leading to the formation of GLA and ALA, respectively, and then ALA (Delta(6) des) --> SDA. The biosynthesis according to the scheme: GLA (Delta(15) des) --> SDA is highly unlikely.

Changes in lipid composition of the oleaginous fungus Cunninghamella echinulata were monitored during growth. Lipid fractions and individual lipid classes varied in amount, relative proportions, and fatty acid profile depending on the developmental stage. Neutral lipids (N), comprised mainly of triacylglycerol, were accumulated in the fungal mycelium during both the late exponential and the stationary growth phases with a concomitant decrease in the amount of polar lipids. While fatty acid composition of N fraction remained almost constant, individual N classes showed a noticeable alteration in gamma-linolenic acid (GLA) concentration. The glycolipid plus sphingolipid (G+S) fraction consisted mainly of monoglycosylglycerol and diglycosylglycerol. The sugar composition of G+S fraction was analyzed and showed a partial replacement of galactose for glucose as growth proceeded. Phospholipid (P) major classes were phosphatidylcholine (PC) and phosphatidylethanolamine, followed by phosphatidylinositol, phosphatidylserine, and diphosphatidylglycerol. P fatty acid composition showed significant changes with time, resulting in a considerable drop in the unsaturation index of this fraction. While in mid exponential growth phase, all P classes contained more than 20% w/w GLA of total fatty acids, and their concentration decreased to 12-17% w/w, except for the PC class where GLA concentration remained at high levels (e.g., more than 20% w/w). The constant level of GLA in PC at all growth phases suggests that PC was the major source of GLA. Sterol analysis showed that their concentration increased during growth, whereas ergosterol was the major component.

Fatty acids have been shown to cause death of rat and human primary pancreatic beta cells and of insulin-producing cell lines. These studies focused mainly on saturated and monounsaturated FA such as palmitic, stearic and oleic acids. In this study, we have performed a comparison of the toxicity of a wider range of FA. The toxicity of different FA to insulin-producing RINm5F cells was assessed by flow cytometry measuring loss of plasma membrane integrity and increase in DNA fragmentation. Additionally, the FA induced neutral lipid accumulation and the FA composition were determined. Palmitic, linoleic, gamma-linolenic, oleic, stearic, and eicosapentaenoic acid caused DNA fragmentation of insulin-producing RINm5F cells. Loss of membrane integrity was mainly caused by linoleic and gamma-linolenic acid. There was no correlation between cytotoxicity and the abundance of the FA in the cells as determined by HPLC analysis. Taken as whole, the toxic effect of the FA on insulin-producing RINm5F cells varied irrespective of the chain length and the degree of unsaturation. In these cells PA and LA exhibited the highest toxicity, whereas AA was not toxic. In addition, the toxicity of most tested FA was inversely related to low NLA, except for AA and EPA. The results of this study contribute to the understanding of the role of FA in the impairment of pancreatic beta cell function that occurs in type 2 diabetes and obesity.

The distribution of gamma-linolenic acid (GLA) was studied in the seed oil of six Cape Verdian Boraginaceae. The GLA ranges from trace levels in the three Heliotropum surveyed to 22.2% on saponifiable oil in Echium stenosiphon. All Echium species had GLA percentages in their seed oil around 20%. Echium seeds yield saponifiable oil from 15.8% (E. stenosiphon) to 17.3% (E. hypertropicum).

Intravenous lipid emulsions (ILE) have demonstrated advantages including prevention of essential fatty acid (EFA) deficiency; however, too much EFA can down regulate fatty acid elongation leading to an imbalance of nutritional compounds in plasma and cell membranes. An olive oil-based ILE containing long-chain triacylglycerols (LCT) with a low content (20 %) of PUFA was administered for home parenteral nutrition (HPN) and compared with a conventional soyabean oil-based ILE (PUFA content, 60 %). Thirteen patients (26-92 years) with stable intestinal failure were randomised after a 1-month run-in period with a medium-chain triacylglycerols-LCT-based ILE, to receive 3 months of HPN with either olive oil- (n 6) or soyabean oil-based (n 7) ILE. The nutritional impact and safety of HPN, oral intakes and absorption rates, phospholipid fatty acids in plasma and lymphocyte cell membrane were assessed. The only clinical event reported was one case of pneumonia (soya group). In both groups, 20 : 3n-9:20 : 4n-6 ratios remained within normal ranges (0.03-0.07). There was a significant increase of gamma-linolenic acid (gamma-LA) in plasma and lymphocyte cell membrane (P=0.02) and of oleic acid in plasma (P<0.01) in the olive compared with the soya group. A significant correlation was found between gamma-LA (day 90 - day 0) in plasma and PUFA parenteral intakes (P=0.02), but neither with fat intakes nor with fat absorption rates. In conclusion, plasma and lymphocyte EFA pattern remained in normal ranges without EFA deficiency with both lipid emulsions, despite a lower content of n-3 and n-6 series with the olive oil-based ILE.

Objective: To measure the saponification value and fatty acid formation of evening primrose oil, to study the effects of pH value on production yield and fatty acid formation during the saponification reaction, and to provide rationales for the selection of raw material, the enhancement of production yield of saponification, and the encapsulation of gamma-linolenic acid with urea., Method: To measure fatty acid's formation with gas chromatographic method and to measure the saponification value., Result: The content of gamma-linolenic acid is 7%-10% in evening primrose oil. The content of gamma-linolenic acid is inversely correlated with that of unsaturated fatty acid. The saponification value, the amount of KOH for saponification of evening primrose oil, and the pH value for subsequent isolations of oils are determined. From the measurement of fatty acids of evening primrose oil in two different cultivation locations, the content of gamma-linolenic acid is determined to be 7%-10%, unsaturated oils account for 90%., Conclusion: The saponification value of evening primrose oil is between 180-200, pH value of isolated oil is 1.5-2.0 after saponification reaction. Fatty acids mainly include palmitic acid, stearic acid, oleic acid, linolic acid and gamma-linolenic acid.

Gamma-linolenic acid (GLA, C18:3delta(6, 9, 12) is one of nutritionally important polyunsaturated fatty acids in human and animal diets. Vast majority oilseeds crops do not produce GLA. Delta6-fatty acid desaturase (D6D) is the rate-limiting enzyme, which catalyzes the conversion of linoleic acid (LA) and alpha-linolenic acid (ALA) to GLA and octadecatetraenoic acid (OTA). In this study, a delta6-fatty acid desaturase gene isolated from Mortierella isabellina was transformed into some soybean cultivars Jilin 35, Jilin 47, Suinong 10, Suinong 14 and Heinong 37 successfully by agrobacterium-mediated cotylendon node transformation system. The results of PCR analysis, Southern blotting and Northern blotting with transgenic plants indicated that target gene was integrated into transgenic soybean genome and expressed at the level of RNA. Meanwhile, total fatty acids were extracted from transgenic seeds and methyl-esterified. Analysis of gas chromatograph (GC) showed that a novel peak corresponding to the standard of GLA methyl ester was detected, the highest percentage of gamma-lenolenic acid to total fatty acids in transgenic seeds was 27. 067%, which indicated that Mortierella isabellina delta6-fatty acid desaturase gene was expressed in transgenic soybean. It is so far the first report on the expression of delta6-fatty acid desaturase gene in transgenic soybean in the world.

The fatty acid compositions of seeds from 29 black currant genotypes were determined using a rapid small-scale procedure. There was interest in alpha-linolenic, stearidonic, and, especially, gamma-linolenic acid (GLA) contents, and most samples showed values between 11.1 and 18.7%, between 2.5 and 4.5%, and between 11.6 and 17.4%, respectively. However, six genotypes exhibited gamma-linolenic contents >18%, and values >20% were recorded in four of these genotypes. The fatty acid contents of the six genotypes were also analyzed by using a conventional procedure, and only slight differences in fatty acid composition were found between the two methods. Although GLA content was not strongly correlated with juice parameters, some genotypes had both high GLA contents and desirable juice characteristics. The results obtained provide evidence that it is possible to select for GLA contents without negatively affecting juice quality, and both aspects can be combined in a single cultivar, thereby increasing the added value of the whole fruit.

A cDNA sequence putatively encoding a Delta(6)-fatty acid desaturase was isolated from Rhizopus arrhizus using reverse transcription polymerase chain reaction and rapid amplification of cDNA ends methods. Sequence analysis indicated that this cDNA sequence had an open reading frame of 1377 bp encoding 458 amino acids of 52 kDa. The deduced amino acid sequence showed high similarity to those of fungal Delta(6)-fatty acid desaturases which comprised the characteristics of membrane-bound desaturases, including three conserved histidine-rich motifs and hydropathy profile. A cytochrome b(5)-like domain was observed at the N-terminus. To elucidate the function of this novel putative desaturase, the coding sequence was expressed heterologously in Saccharomyces cerevisiae strain INVScl. The result demonstrated that the coding product of the sequence exhibited Delta(6)-fatty acid desaturase activity by the accumulation of gamma-linolenic acid.

Gamma-linolenic acid (GLA, C18:3delta6 ,9,12), an essential polyunsaturated fatty acid, plays an important role in hormone regulation and fatty acid metabolization. Delta6-fatty acid desaturase (D6D) is the rate-limiting enzyme of the desaturation of linoleic acid (C18:2delta9,12) in the production of gamma-linolenic acid. A deficiency of GLA may have occurred when delta6-fatty acid desaturase activity decreases in aging, stress, diabetes, eczema, and some infections. To establish a new expression system for delta6-fatty acid desaturase gene in Pichia pastoris, which is an increasingly popular heterologous gene expression system, a gene encoding delta6-fatty acid desaturase from Mortieralla alpina was isolated by PCR amplification. The PCR product was then digested by EcoR I and Not I and subcloned into the intracellular expression vector pPIC3.5K to generate the recombinant vector pPIC3.5K-MA6. The resulting vector was linearized by Sac I and electroporated into P. pastoris SMD1168 (his- pep-) host cells. After electroporation, aliquots were spreaded on the MDS plates and incubated at 30 degrees C for three days until colonies appeared. Those transformants were subsequently screened for clones with high copy number by using the YPD plates containing G418. To identify the D6D constructs that were produced, chromosomal DNA of the transformants were prepared and used as template for PCR with the primer 5' AOX and 3' AOX. The PCR product of Mut+ recombinants was shown as a band of 1.38 kb of D6D gene and the product of 2.2 kb of AOX1 gene, while the product of Mut(s) transformants only was shown as a band of 1.38 kb of the D6D gene.To further confirm the transformants containing a functional D6D gene, the positive clones were selected and induced by methanol for expression. Those induced cultures were taken for analyses of the intracellular fatty acid composition by GC. The resultant chromatograms of fatty acid methyl esters showed that a novel peak was detected, which was not apparent in the case of control. Comparisons of the retention times of the newly yielded peaks with those of authentic standards have anticipated that the fatty acid is GLA. And this prospects was positively supported by definitive assignments of the compounds by GCMS analyses. Thus, the active delta6-fatty acid desaturase was expressed intracellularly in P. pastoris and gamma-linolenic acid reached 16.26% of the total fatty acid in recombinant P. pastoris strains. It was the first report about the expression of Mortieralla alpina D6D gene in P. pastoris.

Virgin olive oil (VOO) compared with fish oil (FO) and evening primrose oil (PO) on the ability of stimulated leukocytes to produce inflammatory mediators was investigated in rats. Weaned Wistar rats were fed a basal diet (BD) (2% by weight of corn oil) or diets containing 15% by weight of VOO, PO, or FO. After 8 weeks, glycogen-elicited peritoneal polymorphonuclear leukocytes, mainly neutrophils, were isolated. The calcium-ionophore stimulated neutrophils (2.5 x 10(6) cells/mL) obtained from rats fed the different oils produced a higher release of lysosomal enzymes (beta-glucuronidase, lysozyme, and myeloperoxidase [MPO]) compared with those fed BD. The production of reactive oxygen species (ROS) in response to the stimulant, 12-O-tetradecanoyl-phorbol-13-acetate (TPA), by neutrophils from the VOO group (15.44 nmol of O(2)(-) and 6.56 nmol of H(2)O(2)) was similar to the BD group (12.01 nmol O(2)(-) and 8.49 nmol H(2)O(2)) and significantly lower than the PO (20.90 nmol O(2)(-) and 10.84 nmol H(2)O(2)) and FO (20.93 nmol O(2)(-) and 12.79 nmol H(2)O(2)) groups. The cyclooxygenase-derived eicosanoid production was reduced by the lipid enrichment of the diets. Whereas the generation of prostaglandin E(2) (PGE(2)) was significantly decreased in VOO (5.40 ng/mL), PO (4.95 ng/mL), and FO (1.44 ng/mL) groups compared with BD (8.19 ng/mL), thromboxane B(2) (TXB(2)) reduction was especially significant in neutrophils from the FO diet group (14.67 ng/mL compared with 26.69 ng/mL from BD). These experimental data suggest that FO and PO, as well as VOO, could be considered a valuable strategy in preventing the generation of some inflammatory mediators.

Growth and lipogenesis of fungus Mucor lusitanicus 306 D producing gamma-linolenic acid was studied under various regimes of nitrogen and carbon nutrition. Media containing food industry wastes such as maize extract, molasses, and protein hydrolysate were used. Content of gamma-linolenic acid was higher when using carbohydrates such as glucose and molasses as carbon sources and urea as a nitrogen source. At high glucose concentration (100 g/l), fed batch cultivation provided high content of gamma-linolenic acid in lipids (1 g/l). After extraction of lipids, fungus biomass contained 42% proteins with all essential amino acids. Defatted biomass was shown to be effectively assimilated by minks.

Objective: The effect of dietary borage oil (rich in the gamma-linolenic acid [GLA]) on insulin sensitivity and lipid metabolism was compared with that of fish oil (rich in n-3 polyunsaturated fatty acids [PUFAs]) in high fat (HF) diet-induced insulin resistance (IR) of rats., Methods: Male Wistar rats were fed ad libitum for 3 weeks a standard laboratory chow (Controls) or high fat diet consisting of 70-cal % fat. In addition, a group of rats was fed high fat (HF) diet where a part of saturated fat was replaced with fish oil as a source of n-3 PUFAs (HF+FO), or borage oil as a source of GLA (HF+GLA). In vivo insulin action was assessed by the euglycemic hyperinsulinemic clamp. Glucose, insulin, free fatty acids (FFA), triglycerides (Tg) and glycerol levels in blood and tissue depots were also measured., Results: Increased levels of Tg, FFA and glycerol in circulation after HF diet were accompanied by their raised accumulation in insulin sensitive tissues. FO feeding lowered the concentration of all lipids in serum and prevented their accumulation in both tissues. On the other hand GLA supplementation into the high fat diet did not suppress increased levels of Tg, FFA and glycerol in circulation and tissue depots as well. FO feeding significantly reduced HF diet-induced in vivo IR, while GLA supplementation did not improve the in vivo insulin sensitivity in HF diet induced insulin resistance., Conclusions: 1. Substitution of FO into the high fat diet led to an improvement of in vivo insulin action; 2. this insulin sensitizing effect of FO was accompanied by a decrease of circulating Tg, FFA and glycerol levels in the postprandial state and by a lower lipid content in liver and skeletal muscle. 3. on the opposite, GLA treatment failed to improve in vivo insulin action; and 4. was associated with an adverse effect on lipid levels both in circulation and tissue depots.

Objective: We have shown previously that the impaired insulin action in hereditary hypertriglyceridemic (hHTg) rat is accompanied by a specific fatty acid (FA) profile in the insulin target tissues, possibly due to a desaturation defect. Thus, the aim of this study was to measure the enzymatic activity and gene expression of delta-6 desaturase in liver of hHTg rats and the tissue FA composition in relation to insulin action., Methods: Glucose, triglycerides and insulin in plasma were measured using commercially available enzymatic sets. The hepatic delta-6 desaturase activity in hHTg rats was determined radiometrically in a microsomal fraction using the 1-14C-linoleic acid as substrate. delta-6 Desaturase gene expression was measured by the Northern blot technique using a specific cDNA probe. Tissue FA profile was determined by gas chromatography in the total lipid fraction extracted to chloroform. The glucose turnover rate was measured in conscious freely moving animals with the aid of euglycemic hyperinsulinic clamp method., Results: Tissue triglycerides showed a high accumulation in skeletal muscle of hHTg rats. In the liver of these animals, a defect in delta-6 desaturase enzymatic activity was found, while the gene expression for delta-6 desaturase was not changed. Such decreased delta-6 desaturase activity in the liver was linked to a decrease of delta-6 desaturase index as calculated from the liver FA composition. Also the concentration of arachidonic acid (a final metabolite in the biosynthesis of polyunsaturated fatty acids of the n-6 series) was significantly decreased in hHTg rat liver. These changes in FA metabolism were accompanied by a decreased glucose infusion rate (a measure of in vivo insulin action) required to maintain euglycemia at hyperinsulinemia in hHTg rats, and correlated with the hepatic delta-6 desaturase activity., Conclusions: 1. hHTg rats showed a reduced activity of the delta-6 desaturase in liver without any changes in gene expression for this enzyme; 2. such impairment is accompanied by a lower delta-6 desaturase index (18:2n-6/18:3n-6) found in the liver of these animals and by specific FA profiles in the tissues, particularly regarding the amount of long-chain PUFAs and 18:2n-6 metabolites; and (4) these alterations seem to be related to the impaired insulin action of hHTg rats.

Two New Age foods which contain high concentrations of whole food nutrients are the single-celled microalgae Chlorella and Spirulina. They are accepted as functional foods, which are defined as products derived from natural sources, whose consumption is likely to benefit human health and enhance performance. These foods are used as a supplement/ingredient or as a complete food to enhance the performance and state of the human body, or improve a specific bodily function. Functional foods are used mainly as products to nourish the human body after physical exertion or as a preventive measure against ailments. We determined the fatty acid compositions, particularly polyunsaturated fatty acid compositions, of Chlorella and Spirulina by capillary column-gas chromatography. The data obtained show that Spirulina contains unusually high levels of gamma-linolenic acid, an essential polyunsaturated fatty acid.

Fourteen species of the genus Echium (Fam. Boraginaceae) collected in the Macaronesia were surveyed in a search for high levels of gamma-linolenic acid (GLA, 18:3omega6) in the seed oil. High amounts of this fatty acid were found in all of them, ranging from 18.85% (E. pitardii var. pitardii) to 27.42% (E. gentianoides) on total seed fatty acids. The GLA content related to total seed weight was also significant, ranging from 1.26% (E. handiense) to 8.22% (E. gentianoides). In addition, considerable amounts of stearidonic acid (SA, 18:4omega3) were detected, ranging from 3.78% (E. bonnetii var. bonnetii) to 8.81% (E. pininana) on total fatty acids. Besides all the perennial species, the four herbaceous Echium taxa endemic to the Macaronesia also showed high GLA percentages. This is in contrast to the low GLA level found in continental Echium species, all of them bearing an herbaceous habit. These results are in good agreement with the available genetic data and show the ability of GLA to discriminate between Macaronesian and continental Echium species. The analysis of five other Macaronesian species belonging to plant families rich in GLA are also reported.

Background: The increased consumption of n-6 polyunsaturated fatty acids (PUFA) has been shown to coincide with the increased prevalence of atopic diseases. We aimed to investigate whether maternal diet and atopic status influence the PUFA composition of breast milk and the serum lipid fatty acids of infants., Methods: Maternal diet was assessed by a food questionnaire. The PUFA composition of breast milk obtained at 3 months from 20 allergic and 20 healthy mothers and of their infants' (10 atopic and 10 nonatopic/group of mothers) serum lipids was analyzed., Results: Although no differences in maternal PUFA intake were observed, the breast milk of allergic mothers contained less gamma-linolenic acid (18:3 n-6) than that of healthy mothers. Similarly, atopic infants had less gamma-linolenic acid in phospholipids than healthy infants, although n-6 PUFA were elevated in other serum lipid fractions in atopic infants. The serum lipid fatty acids in atopic infants did not correlate with those in maternal breast milk., Conclusion: Our results suggest that dietary n-6 PUFA are not as readily transferred into breast milk or incorporated into serum phospholipids, but may be utilized for other purposes, such as eicosanoid precursors, in allergic/atopic individuals. Subsequently, high dietary proportions of n-6 PUFA, or reduced proportions of regulatory PUFA, such as gamma-linolenic acid and n-3 PUFA, may be a risk factor for the development of atopic disease.