Proportion Of Monounsaturated Fatty Acids Research Articles

Valoración nutricional de la dieta sin gluten. ¿Es la dieta sin gluten deficitaria en algún nutriente?

IntroductionThe gluten-free diet has traditionally been accepted as a healthy diet, but there are articles advocating that it may have some nutritional deficiencies. The current study assesses whether there was any change in the contributions of calories, essential elements, proportion of fatty acids, vitamins, minerals and fiber in children who were diagnosed with celiac diseases, comparing the diet with gluten prior one year after diagnosis with the diet without gluten to the year of diagnosis. The level of clinical or analytical impact that nutritional deficits could have was also assessed. Material and methodsA prospective,descriptive, observational study in which information was collected from a dietary survey, anthropometric and analytical data at pre-diagnosis of celiac disease and following a gluten diet and one year after celiac disease diagnosis, under gluten-free diet. ResultsA total of 37 patients meet the study criteria. A decrease in the intake of saturated fatty acids was found, with an increase of monounsaturated fatty acids and an increase in the intake of phosphorus in the diet without gluten. A deficient intake of vitamin D was found in both diets. Clinically, at year of gluten-free diet there was an improvement in weight and size. Analytically, there was an improvement in hemoglobin, ferritin, vitamin D, and parathyroid hormone in plasma. ConclusionThe gluten-free diet has minimal deficiencies, similar to those present in the diet with gluten, with an improvement in the lipid profile by increasing the proportion of monounsaturated fatty acids to the detriment of saturated fatty acids.

Use of Avocado and Tomato Paste as Ingredients to Improve Nutritional Quality of Pork Frankfurter

<p>The objective of this research was to study the effect of avocado pulp (A) and tomato paste (T) addition on the physicochemical, nutritional and sensory quality of pork frankfurters. Treatments were: 1) Control; 2) A10 = 10% A; 3) A20 = 20% A; 4) T10 = 10% T; 5) T20 = 20% T; and 6) A10+T10 = 10% A+10% T. Colour (<em>L*</em>, <em>a*</em> and <em>b*</em>), fatty acid profile, contents of phenols and flavonoids, and antioxidant capacity were measured. In the same way, sensory analysis was evaluated. Tomato paste decreased <em>L*</em> but increased (P < 0.05) <em>a</em>* and <em>b</em>* values. On the other hand, A did not affect <em>L*</em>, decreased <em>a*</em> and increased <em>b*</em>. Avocado pulp increased (P < 0.05) the proportion of monounsaturated fatty acids in the finished product. Antioxidant activity increased (P < 0.05) with incorporation of T, much higher than that observed by adding A. Frankfurters with T and with a combination of T and A had the best acceptance by the sensory panel. The use of T and A can be a good strategy to improve nutritional quality and antioxidant properties of pork frankfurters.</p>

The effects of conjugated linoleic acid on growth performance, carcass traits, meat quality, antioxidant capacity, and fatty acid composition of broilers fed corn dried distillers grains with solubles

This study investigated the effects of dietary supplementation with conjugated linoleic acid (CLA) on the growth performance, carcass traits, meat quality, antioxidant capacity, and fatty acid composition of broilers fed corn dried distillers grains with solubles (DDGS). Four hundred eighty 1-d-old broilers were randomly assigned to 4 groups, consisting of 6 replicates with 20 broilers each. Broilers were allocated 1 of 4 diets and fed for 49 d in a 2 × 2 factorial design. The dietary treatments consisted of 2 levels of DDGS (0 or 15%) and 2 levels of CLA (0 or 1%). The results of growth performance analyses showed that dietary supplementation with 1% CLA, 15% DDGS, or both in broilers had no significant effects on ADG, ADFI, and feed/gain (P > 0.05). Dietary supplementation with 15% DDGS did not significantly affect meat color values, drip loss percentage, pH value at 15 min, crude fat content, or shear force value (P > 0.05). Diets supplemented with 15% DDGS decreased the proportions of saturated fatty acids (P < 0.05) and monounsaturated fatty acids but increased the proportion of polyunsaturated fatty acids of the thigh meat (P < 0.05). Diets supplemented with 1% CLA significantly decreased the abdominal fat percentage (P < 0.05). Supplementation with 1% CLA increased the crude fat content and decreased the color (b*) value and shear force value of the breast meat (P < 0.05). Diets supplemented with 1% CLA increased the total superoxide dismutase activity of the serum, breast meat, and liver, and decreased the malondialdehyde content of the serum and breast meat (P < 0.05). Supplementation with 1% CLA decreased the proportion of monounsaturated fatty acids and increased the proportion of saturated fatty acids (P < 0.05). Accumulation of CLA in the thigh meat was significantly increased (P < 0.05) with increasing CLA level in the diet. In conclusion, dietary supplementation with 1% CLA had positive effects on meat quality, antioxidant capacity, and fatty acid composition of broilers, although it had no significant effect on growth performance.

Cancer death is related to high palmitoleic acid in serum and to polymorphisms in the SCD-1 gene in healthy Swedish men

A high proportion of monounsaturated fatty acids (MUFAs) or a high ratio of MUFAs to saturated fatty acids in plasma, reflecting a high activity of the lipogenic enzyme stearoyl-CoA desaturase-1 (SCD-1), has been shown to be related to cancer death and incidence in some studies. The objective was to study whether the serum cholesteryl ester proportion of palmitoleic acid [16:1n-7 (16:1ω-3)] and the ratio of palmitoleic to palmitic acid (16:1n-7/16:0), as an estimation of the activity of SCD-1, are related to cancer death and to investigate whether polymorphisms in the SCD-1 gene are related to cancer mortality. A community-based cohort of 50-y-old men was followed for a maximum of >40 y. Survival analysis was used to relate fatty acid composition in serum, analyzed at baseline by gas-liquid chromatography (n = 1981), and single nucleotide polymorphisms in the SCD-1 gene (n = 986) to cancer death. A 7-d dietary record was completed at age 70 y (n = 880). The proportions of 16:1n-7 and the ratio of 16:1n-7 to 16:0 were associated with cancer mortality during follow-up in a comparison of the highest with the lowest quartile of 16:1n-7 (adjusted HR: 1.37; 95% CI: 1.04, 1.82). Inherited variance of the SCD-1 gene seemed to be related to cancer death, especially among men with a low proportion of PUFA in the diet in a comparison of the highest with the lowest weighted genetic risk score (HR: 2.14; 95% CI: 1.13, 4.04). The findings are compatible with the hypothesis that there is an association between endogenously synthesized MUFAs and cancer death.

Momordica Charantia Seed Oil Methyl Esters: A Kinetic Study And Fuel Properties

Due to growing concerns such as increasing energy demand and the environmental issues-related fossil energy problems caused by consumption of fossil energy, it is needed to focus on nonedible oils for biodiesel production. In the present research work, the seed oil of Momordica charantia (M. charantia) was for the first time appraised as possible nonedible oil for synthesis of biodiesel. M. charantia has oil content (36.10 ± 4.20%), high acid value (1.82 mg KOH g−1), and its oil enable base-catalyzed transesterified for biodiesel production after acid pretreatment. It was transesterified under standard conditions at 6:1 molar ratio of methanol to oil; sodium methoxide (1.00 wt.% in relation to oil mass) as a catalyst; 60°C reaction temperature and 90 min of reaction time. At optimum conditions biodiesel yield of 93.2% was acquired. The reaction followed first order kinetics. The activation energy (E A) was 254.5 kcal mol−1 and the rate constant value was 1.30 × 10−4 min−1 at 60°C. Gas chromatography investigation of M. charantia seed oil methyl esters (MSOMEs) depicted that the fatty acid composition comprises a high proportion of mono-unsaturated fatty acids (64.11 ± 5.02%). MSOMEs were also characterized using Fourier Transform Infrared and 1H Nuclear Magnetic Resonance spectroscopy. The tested fuel properties of the MSOMEs, except oxidative stability, were conformed to EN 14214 and ASTM D6751 standards. The low-value oxidative stability of MSOMEs can be solved by adding antioxidants additives. In summary, M. charantia oil has potential as nonedible raw material for biodiesel production.

UTS2R gene polymorphisms are associated with fatty acid composition in Japanese beef cattle

Fatty acid composition of beef adipose tissue is one of its important traits because a high proportion of monounsaturated fatty acid is related to favorable beef flavor and tenderness. In this study, we searched polymorphisms in full length coding DNA sequence of urotensin 2 recepter and investigated the effects on fatty acid composition (C14:0, C14:1, C16:0, C16:1, C18:0, C18:1, C18:2, monounsaturated fatty acid, saturated fatty acid). Eight single nucleotide polymorphisms (SNP) were identified by sequence comparison among eight animals, including five Japanese Black and three Holstein cattle. One of these SNP (c.866C>T) was predicted to cause amino acid substitutions (P289L) and the other seven synonymous SNP, including c.267C>T, were presumed to be in linkage disequilibrium. Therefore we selected two SNP (c.267C>T and c.866C>T) for further analysis. We investigated associations between these genotypes and fatty acid composition in three Japanese Black populations (n=560, 245 and 287) and a Holstein population (n=202). Tukey-Kramer's honestly significant difference test revealed that CC genotype in c.267C>T indicated lower C14:0 and higher C18:1 than the other genotypes in Japanese Black cattle and CC genotype in c.866C>T showed lower C16:1 than CT genotype in Holstein cattle (P<0.05). These results suggested that these genotypes would contribute to production of high-grade meat as selection markers in beef cattle.

Carboxylicivirga gen. nov. in the family Marinilabiliaceae with two novel species, Carboxylicivirga mesophila sp. nov. and Carboxylicivirga taeanensis sp. nov., and reclassification of Cytophaga fermentans as Saccharicrinis fermentans gen. nov., comb. nov.

Two facultatively anaerobic mesophilic bacteria, strains MEBiC 07026(T) and MEBiC 08903(T), were isolated from two different tidal flat sediments and both strains showed approximately 92.2 % 16S rRNA gene sequence similarity with [Cytophaga] fermentans DSM 9555(T). 16S rRNA gene sequence similarity between the two new isolates was 97.5 % but levels of DNA-DNA relatedness between the two were 31.3-31.8 %. Phylogenetic analysis revealed that the two isolates and [Cytophaga] fermentans DSM 9555(T) were affiliated with the family Marinilabiliaceae in the class Bacteroidia. The dominant fatty acids of strains MEBiC 07026(T), MEBiC 08903(T) and [Cytophaga] fermentans DSM 9555(T) were branched-type or hydroxylated C15 : 0, but [Cytophaga] fermentans DSM 9555(T) contained a higher proportion of anteiso-branched fatty acids. The two new isolates contained a markedly higher proportion of monounsaturated fatty acids than other members of the family Marinilabiliaceae. The major respiratory quinone of the strains was MK-7. Strains MEBiC07026(T) and MEBiC08903(T) utilized a wide range of carboxylic acids whereas [Cytophaga] fermentans DSM 9555(T) utilized carbohydrates rather than carboxylic acids. The DNA G+C content of the novel strains was about 44 mol% but that of [Cytophaga] fermentans DSM 9555(T) revealed from the genome sequence was 37.6 mol%. Based on evidence from this polyphasic taxonomic study, a novel genus, Carboxylicivirga gen. nov., is proposed in the family Marinilabiliaceae with two novel species, Carboxylicivirga mesophila sp. nov. with type strain MEBiC 07026(T) ( = KCCM 42978(T) = JCM 18290(T)) and Carboxylicivirga taeanensis sp. nov. with type strain MEBiC 08903(T) ( = KCCM 43024(T) = JCM 19490(T)). Additionally, [Cytophaga] fermentans DSM 9555(T) ( = ATCC 19072(T)) is reclassified as Saccharicrinis fermentans gen. nov., comb. nov.

Effect of micro-encapsulated n-3 fatty acids on quality properties of two types of dry sausages

Dry sausages are popular traditional meat products. As these products are a rich source of animal fat, there is an effort to improve their fatty acid ratio. The aim of this work was to study the effect of micro-encapsulated n-3 fatty acids added into dry sausages. Samples of dry sausages (Poličan and Vysočina) enriched with unsaturated fatty acids (36 g for 6 kg of mixture) and rosemary extract (0.3 g·kg-1) were made along with control samples. Physicochemical, instrumental analyses were performed, fatty acid profile was measured by gas chromatography, and oxidation processes were monitored by determination of thiobarbituric acid reactive substances. No significant differences (P ≥ 0.05) in quality indicators were found between samples, however, there were differences in oxidation processes. Sausages enriched with unsaturated fatty acids showed an increase in thiobarbituric acid reactive substances (&gt; 2 mg·kg-1 and &gt; 3 mg·kg-1 in Poličan and Vysočina, respectively, compared to control). Sausages enriched with unsaturated fatty acids and also with rosemary extract have the similar concentration of thiobarbituric acid reactive substances as the control. An increase in the proportion of monounsaturated fatty acids and polyunsaturated fatty acids was seen in samples of Poličan supplemented with unsaturated fatty acids in combination with rosemary extract. The addition of rosemary extract had also a significant effect in increasing the proportion of unsaturated fatty acids in samples of Vysočina. From the viewpoint of quality indicators, changes in the properties of the product were not seen in any samples.

Effect of age on contents of fatty acids in whole bodies of pheasants throughout their growth

The aim of the work was to evaluate the effect of age on the proportion of particular fatty acids in the whole bodies of pheasants fattened for up to 118 days of age. In the experiment, 232 chicks of common pheasants (Phasianus colchicus) were used. In the course of the experiment, the required number of pheasants was randomly selected for analysis at regular 10-day intervals. The age of pheasant chicks had a significant effect on the content of all fatty acids. Significant changes in the proportion of fatty acid groups were recorded mainly at 20, 40 and 60 days of age. By 20 days of age the proportion of monounsaturated fatty acids decreased considerably in relation to the increase in the content of polyunsaturated fatty acids, while the n6/n3 ratio decreased markedly. The content of monounsaturated fatty acids increased between day 20 and day 40, causing a simultaneous decrease in polyunsaturated fatty acids. From day 40, the monounsaturated fatty acid content increased gradually till the end of fattening, whereas the reverse trend was observed in the saturated fatty acid content in this period. As for polyunsaturated fatty acids, their presence increased from day 40 to day 60, followed by a gradual decrease till the end of fattening. The results of our work showed the different ability of pheasants to digest and utilize particular fatty acids with varying efficiency throughout their growth. The study brings new findings concerning changes in fatty acid composition of pheasants during fattening.

Continuous production of Chaetoceros calcitrans in a system suitable for commercial hatcheries

Chaetoceros calcitrans is a small, fast-growing diatom with a high nutritional value for filter feeders. It is often used in hatcheries, particularly in the production of bivalve spat. It is widely produced in batch culture systems ranging from carboys to plastic bags to high volume tanks. Continuous culture of C. calcitrans has generally not been successful due to frequent crashes of the culture. We report the continuous culture of C. calcitrans in a hanging plastic bag system that is suitable for use in commercial hatcheries. Runs of continuous production lasted up to 125d, with an average bag life of 24.4d. Crashes occurred at irregular intervals in individual bags and caused the cell concentration to drop by up to three orders of magnitude. Cultures recovered over a few days following a crash. The temporary reduction of production due to crashes in individual bags was compensated by a 30% higher production than required. At dilution rates of 1.0–1.3volume exchangesd−1 the system produced 7–13×106cellsmL−1d−1. The cell diameter mode as determined by a Coulter Counter was 2.8–3.0μm. The cells had the typical flat rectangular box shape with well-developed setae. The culturable bacterial population of the algae culture was 105–107colony forming unitsmL−1. Genetic integrity of C. calcitrans and monospecific status of the continuous culture were maintained over 7 sequential bag-to-bag transfers during a 125-day run. The fatty acid profiles of continuous and batch cultures of C. calcitrans were similar. Growth and survival of Greenshell™ mussel (Perna canaliculus) larvae were identical when fed with C. calcitrans batch culture or continuous culture delivered directly from the harvest line. When continuous culture was first collected over 24h, diluted and then delivered to the rearing tanks over 24h, larval growth was markedly slower (24d to reach settlement competency compared to 21d for the other two treatments); however the subsequent settlement success of competent larvae was not statistically different between the three diets (‘Carboy’, ‘Continuous/Harvest line’, ‘Continuous/Feed-out bin’; 33.9–35.5% settled). Concomitant to the differences in larval performance we observed a difference in larval fatty acid profile: lower-performing larvae had a markedly lower proportion of mono-unsaturated fatty acids and a markedly higher proportion of poly-unsaturated fatty acids. Lower performance and different fatty acid profiles of larvae fed the ‘Continuous/Feed-out bin’ diet appeared to be caused by unidentified changes that occurred during storage of the C. calcitrans culture.

Biochemical and molecular evidence of a Δ9 fatty acid desaturase from Ensifer meliloti 1021

It has been reported that Ensifer meliloti presents a high proportion of monounsaturated fatty acids and has a putative desaturase gene designated as PhFAD12 (National Centre for Biotechnology Information), encoding a putative Δ12 desaturase-like protein. In this work, we report the desaturation capacity and characterisation of this gene encoding the putative fatty acid desaturase of E. meliloti 1021. This gene was also isolated from the rhizobial strain and overexpressed in Escherichia coli.Compared to a control, the expression of this gene in the transformed strain decreased the levels of palmitic and stearic acids, enhanced palmitoleic and cis-vaccenic levels, and allowed for the detection of oleic acid. E. coli overexpressing the putative desaturase gene was capable of desaturating palmitic and stearic acids to monounsaturated fatty acids, similarly to the rhizobial strain. Our studies show that AAK64726 encodes a Δ9 desaturase instead of a Δ12 desaturase as previously indicated. This work describes evidence for the presence of a desaturase-mediated mechanism in monounsaturated fatty acid synthesis in E. meliloti 1021, which is modified by high growth temperature. This mechanism supplements the anaerobic mechanism for unsaturated fatty acid synthesis.

Forage fish quality: seasonal lipid dynamics of herring (Clupea harengus L.) and sprat (Sprattus sprattus L.) in the Baltic Sea

Abstract Røjbek, M. C., Tomkiewicz, J., Jacobsen, C., and Støttrup, J. G. Forage fish quality: seasonal lipid dynamics of herring (Clupea harengus L.) and sprat (Sprattus sprattus L.) in the Baltic Sea. – ICES Journal of Marine Science, 71: . This study investigates lipid content and fatty acid composition of two important forage fish, sprat (Sprattus sprattus) and herring (Clupea harengus) in the Baltic Sea ecosystem. Seasonal variation in lipids was studied during three periods following the annual reproductive cycle considering potential differences relating to fish size, sex, and reproductive status. The isopod Saduria entomon, being at times an important prey for predatory fish, was included for comparison. In both sprat and herring, lipid content and absolute contents of essential polyunsaturated fatty acids (PUFAs) varied seasonally with high levels towards the end of the annual zooplankton production cycle, succeeded by a decline. Lipid content and fatty acid composition differed significantly between sprat and herring. Sprat lipid content was higher than herring, increasing with fish size and characterized by large proportions of monounsaturated fatty acids. Herring lipid content was related to the reproductive cycle and proportions of PUFAs were high compared with sprat. Levels of essential PUFAs were high in S. entomon compared with clupeids rendering it a valuable alternative prey species in the Baltic Sea ecosystem. The lipid dynamics of forage fish and benthos, combined with changes in availability and abundance, will affect growth and reproduction of their predators.

Genetic ancestry modifies fatty acid concentrations in different adipose tissue depots and milk fat

The objective of this study was to determine the effect of cow genetic strain on fatty acid (FA) profiles in adipose tissue and milk. Adipose samples from two subcutaneous (shoulder and tail-head) and three visceral (kidney channel, mesenteric and omental) depots were obtained post mortem from New Zealand (NZ; n = 8) and North American (NA; n = 8) Holstein-Friesian cows. At the time of slaughter cows were in similar body condition (NZ: 4.0 ± 0.03, NA: 4.0 ± 0.02; ± SD) and stage of lactation (NZ: 90 ± 11.2 d; NA: 83 ± 4.3 d; ± SD). Milk was collected during the a.m. milking prior to slaughter and milk fat was extracted. Adipose and milk fat FA were quantified using gas chromatography. NZ cows had a lower proportion of saturated FA in shoulder, tail-head and omental adipose tissue and a greater proportion of mono-unsaturated FA and an elevated Δ9-desaturase index in shoulder and tail-head adipose tissue. The proportions of individual FA differed between adipose depots, with proportions of de-novo FA greater in subcutaneous compared with visceral adipose depots. Milk from NZ cows contained greater concentrations of short chain FA (C8 : 0-12 : 0) and CLA, and less cis-9 18 : 1 than milk from NA cows. Regression analysis identified moderate associations between milk FA and shoulder adipose tissue FA for 18 : 2 (R(2) = 0.24), 18 : 3 n - 3 (R(2) = 0.39), and polyunsaturated fatty acids (R(2) = 0.38). Results from this study support the hypothesis that genetic strain dictates FA profiles in adipose tissue and milk and may alter the metabolic status of the various adipose depots differently. The data further support the premise that genetic strain affects the metabolic status of the various adipose depots differently. Elucidating the mechanisms that regulate the different adipose depots in the NZ and NA strains will increase our understanding of tissue mobilization and replenishment.

Altered Fatty Acid Profile in the Liver and Serum of Stroke-Prone Spontaneously Hypertensive Rats: Reduced Proportion of cis-Vaccenic Acid

Stroke-prone spontaneously hypertensive rats (SHRSP) are utilized as models for study of the pathogenesis of not only stroke and cardiovascular disorders but also atherosclerosis and metabolic syndrome. Basic information on the profiles of fatty acids and lipid classes in the liver is indispensable to use SHRSP as a model of disorder of lipid metabolism; nevertheless, detailed information on the metabolism of triacylglycerols (TAGs) and fatty acids in the liver of SHRSP is lacking. This study aimed to characterize profiles of lipid classes and fatty acids and to explore the mechanism underlying the characteristic alterations in metabolism of TAGs and fatty acids in the liver of SHRSP, in comparison with spontaneously hypertensive rats (SHR). The characteristic changes observed in SHRSP were (1) markedly lower hepatic TAG contents; (2) altered expressions of genes encoding three enzymes responsible for the control of TAG level, namely, adipose triglyceride lipase (for TAG degradation; up-regulated), carnitine palmitoyltransferase 1a (for fatty acid β-oxidation; up-regulated) and long-chain acyl-CoA synthetase 3 (for glycerolipid synthesis; down-regulated); (3) evidently lower contents and proportions of monounsaturated fatty acids, in particular cis-vaccenic acid (18:1n-7), in the liver and serum; and (4) down-regulation of palmitoleoyl-CoA chain elongase, which is necessary for the biosynthesis of 18:1n-7, in the liver. From the above observations, we concluded that there are significant differences in profiles of lipid classes and fatty acids between SHRSP and SHR, and that altered characteristics in SHRSP are likely responsible for increases in TAG hydrolysis and β-oxidation, and decreases in TAG synthesis and 18:1n-7 synthesis.

Genetic variation in fatty acid composition of subcutaneous fat in cattle

Genetic parameters were estimated for fatty acid composition of subcutaneous beef fat of 1573 animals which were the progeny of 157 sires across seven breeds grown out on pasture and then finished on either grain or grass in northern New South Wales or in central Queensland. There was genetic variation in individual fatty acids with estimates of heritability for the proportions of C14 : 0, C14 : 1c9, C16 : 0, C16 : 1c9, C18 : 0 and C18 : 1c9 fatty acids in subcutaneous beef fat of the order of 0.4 or above. Also substantial correlations between some fatty acids were observed. Genetic correlations between fatty acids and fat depth at the P8 site suggested that much of the genetic variation in fatty acid composition was related to changes in fatness. Selection for decreased fatness resulted in decreased proportions of C18 : 1c9 with concomitant increases in C18 : 0, C14 : 0 and C16 : 0. This suggested that selection for decreased fatness at a given weight will result in a decrease in the proportions of monounsaturated fatty acids in the subcutaneous fat in the carcass with a corresponding increase in the proportions of saturated fatty acids.

Key Fatty Acid Combinations Define Vascular Smooth Muscle Cell Proliferation and Viability

High plasma concentrations of free fatty acids (FFA) and insulin are common features in atherosclerotic patients with type 2 diabetes. FFA, according to their nature, can have various effects on vascular smooth muscle cells (VSMC). These cells play important roles throughout atherosclerosis pathogenesis, from plaque development to plaque instability. Thus, this study aims to assess the impact of two FFA combinations and insulin on murine VSMC viability. The two combinations contain the same FFA but at different ratios, one being richer in saturated fatty acids (SFA) and the other having a higher proportion of monounsaturated fatty acids (MUFA). Both combinations inhibited VSMC proliferation due to their pro-apoptotic potential, with SFA being the major inducers of apoptosis. However, the presence of oleic acid (OLA) attenuated this impact in a dose-dependent manner. OLA had also the capacity to reduce apoptosis rates more strongly when combined with a SFA than when used alone in VSMC treatments. This effect was significant only for specific proportions of these FFA and was even more effective in presence of insulin. These results highlight the presence of a competition between pro-apoptotic and anti-apoptotic mechanisms in VSMC that is dependent on FFA ratios (saturated vs. monounsaturated) and on insulinemia. They also underline the importance of the presence of MUFA such as OLA in diets containing high proportions of SFA.

Degradation state of organic matter in surface sediments from the Southern Beaufort Sea: a lipid approach

Abstract. For the next decades significant climatic changes should occur in the Arctic zone. The expected destabilisation of permafrost and its consequences for hydrology and plant cover should increase the input of terrigenous carbon to coastal seas. Consequently, the relative importance of the fluxes of terrestrial and marine organic carbon to the seafloor will likely change, strongly impacting the preservation of organic carbon in Arctic marine sediments. Here, we investigated the lipid content of surface sediments collected on the Mackenzie basin in the Beaufort Sea. Particular attention was given to biotic and abiotic degradation products of sterols and monounsaturated fatty acids. By using sitosterol and campesterol degradation products as tracers of the degradation of terrestrial higher plant inputs and brassicasterol degradation products as tracers of degradation of phytoplanktonic organisms, it could be observed that autoxidation, photooxidation and biodegradation processes act much more intensively on higher plant debris than on phytoplanktonic organisms. Examination of oxidation products of monounsaturated fatty acids showed that photo- and autoxidation processes act more intensively on bacteria than on phytodetritus. Enhanced damages induced by singlet oxygen (transferred from senescent phytoplanktonic cells) in bacteria were attributed to the lack of an adapted antioxidant system in these microorganisms. The strong oxidative stress observed in the sampled sediments resulted in the production of significant amounts of epoxy acids and unusually high proportions of monounsaturated fatty acids with a trans double bond. The formation of epoxy acids was attributed to peroxygenases (enzymes playing a protective role against the deleterious effects of fatty acid hydroperoxides in vivo), while cis/trans isomerisation was probably induced by thiyl radicals produced during the reaction of thiols with hydroperoxides. Our results confirm the important role played by abiotic oxidative processes in the degradation of marine bacteria and do not support the generally expected refractory character of terrigenous material deposited in deltaic systems.

Effect of processing and storage on the fatty acid composition of n‐3 or n‐6 fatty acid‐enriched eggs

SummaryFresh eggs from hens fed diets supplemented with 4% linseed oil (LO) or sunflower oil (SO) were either directly submitted to pasteurisation, hard‐boiling or scrambling processing, or first submitted to refrigerated storage at 4 °C for 60 day and then to processing. Fresh LO eggs showed higher (P ≤ 0.05) proportions of monounsaturated fatty acids (MUFAs) and n‐3 polyunsaturated fatty acids (PUFAs), but lower (P ≤ 0.05) proportions of saturated fatty acids (SFAs), PUFAs and n‐6 PUFAs than the SO eggs. Storage decreased (P ≤ 0.05) the proportion of PUFAs and increased (P ≤ 0.05) that of MUFAs in egg yolks from both treatments. The pasteurisation process had no effect on the fatty acid composition of fresh eggs from both treatments, but increased (P ≤ 0.05) n‐6 PUFAs and decreased (P ≤ 0.05) n‐3 PUFAs in stored LO eggs. Hard‐boiling and scrambling modified the fatty acid composition of fresh and stored eggs from both treatments by decreasing (P ≤ 0.05) the proportion of PUFAs, particularly of the very long‐chain n‐3 eicosapentaenoic, docosapentaenoic and docosahexaenoic PUFAs. LO eggs showed a higher susceptibility to fatty acid modification upon processing as compared to the SO eggs.

Fatty acid composition of Mongolian mare milk

Fat content and fatty acid composition of milk from mares grazing in two dominant Mongolian ecosystems, Steppe and Forest-steppe, were compared during the summer and autumn seasons. The mares received no additional supplements. Milk fat content, concentration of total saturated fatty acids (SFA) and total unsaturated fatty acids (TUFA) were similar in the two regions and milking seasons. Significant effects of season on individual milk fatty acids were found. The concentrations of caprylic (8:0) and stearic acid (18:0) were highest in summer milk, and the concentration of palmitic acid (16:0) was lower in summer milk. The proportion of monounsaturated fatty acids 14:1, 17:1 and 20:1 was higher in milk from mares grazing on the Steppe than the Forest-steppe. The concentration of SFA was lower and of alpha-linolenic acid (ALA) higher than published for other breeds and feeding conditions. High concentration of gamma-linolenic acid (GLA), especially in the summer, is noteworthy.

Gene Transfer in Leptolyngbya sp. Strain BL0902, a Cyanobacterium Suitable for Production of Biomass and Bioproducts

Current cyanobacterial model organisms were not selected for their growth traits or potential for the production of renewable biomass, biofuels, or other products. The cyanobacterium strain BL0902 emerged from a search for strains with superior growth traits. Morphology and 16S rRNA sequence placed strain BL0902 in the genus Leptolyngbya. Leptolyngbya sp. strain BL0902 (hereafter Leptolyngbya BL0902) showed robust growth at temperatures from 22°C to 40°C and tolerated up to 0.5 M NaCl, 32 mM urea, high pH, and high solar irradiance. Its growth rate under outdoor conditions rivaled Arthrospira (“pirulina” strains. Leptolyngbya BL0902 accumulated higher lipid content and a higher proportion of monounsaturated fatty acids than Arthrospira strains. In addition to these desirable qualities, Leptolyngbya BL0902 is amenable to genetic engineering that is reliable, efficient, and stable. We demonstrated conjugal transfer from Escherichia coli of a plasmid based on RSF1010 and expression of spectinomycin/streptomycin resistance and yemGFP reporter transgenes. Conjugation efficiency was investigated in biparental and triparental matings with and without a “elper”plasmid that carries DNA methyltransferase genes, and with two different conjugal plasmids. We also showed that Leptolyngbya BL0902 is amenable to transposon mutagenesis with a Tn5 derivative. To facilitate genetic manipulation of Leptolyngbya BL0902, a conjugal plasmid vector was engineered to carry a trc promoter upstream of a Gateway recombination cassette. These growth properties and genetic tools position Leptolyngbya BL0902 as a model cyanobacterial production strain.