Major Trans Fatty Acid Research Articles

Impact of Fatty Acids on Obesity-Associated Diseases and Radical Weight Reduction

PurposeFatty acids (FA), particularly polyunsaturated (PUFA) ones, are involved in the regulation of glycemic control, lipid metabolism, and inflammation. The aim of the study was to assess patient FA profile in relation to obesity, lipid and carbohydrate metabolism disturbances, and weight loss.Materials and MethodsThe studied group consisted of 51 patients with extreme obesity, 23 of whom achieved radical weight reduction within 1 year after a laparoscopic sleeve gastrectomy (LSG). FA levels were determined using gas chromatography with flame ionization detection.ResultsPatients with extreme obesity and higher serum PUFA content have lower serum levels of SFA and MUFA (especially myristic, palmitic, lignoceric acids and palmitoleic, oleic acids), as well as lower triglyceride and higher HDL-cholesterol concentrations and it was not influenced by CEPT Taq1B variant. At baseline, the fatty acid profile of patients with type II diabetes differ from patients with dyslipidemia. In patients who had lost weight, significantly lower levels of selected saturated FA and major trans-fatty acid, elaidic, were found. Moreover, the proportion of PUFA was increased.ConclusionIn extreme obesity, higher PUFA exert their favorable effects on serum lipids. Significant weight reduction after the bariatric surgery is associated with beneficial changes in the fatty acid profile.Graphical

Simulation of fatty acid peak profile on a 100-m CP-Sil 88 column and application for analysis of commercial trans fat alternatives in Thailand

A program to simulate fatty acid peak profiles on a gas chromatograph coupled with a 100-m CP-Sil 88 column has been developed. The concept of a quantitative structure-retention relationship (QSRR) with a Gibbs energy additivity approach and Gaussian function was used to create the program, which can be performed on Excel spreadsheets. The present method is applicable for optimizing multi-step temperature-programmed gas chromatography (GC) for determination of fatty acid profiles in samples. Strong correlation coefficients were obtained between experimental and simulated retention times (tR), with R2 = 0.9981. Based on simulation results, the AOAC2012.13 GC condition was recommended for the trans fat analysis. The proposed method was applied to analyze fatty acid compositions in 12 samples of trans fat alternatives, including shortenings, margarines, butter blends and non-dairy creamers, sold commercially in Thailand. The major trans fatty acid (TFA) isomer found after fractionation on Ag-Ion SPE was C18:1t11 (trans-vaccenic acid). The samples contained 0.0–6.3 g TFA/100 g fat, which is similar to the level found in nature. Contents of TFA in the samples determined by GC after fractionation on Ag-Ion SPE were comparable to those obtained by Fourier transform infrared analysis.

Trans-Fatty acids facilitate DNA damage-induced apoptosis through the mitochondrial JNK-Sab-ROS positive feedback loop

trans-Fatty acids (TFAs) are unsaturated fatty acids that contain one or more carbon-carbon double bonds in trans configuration. Epidemiological evidence has linked TFA consumption with various disorders, including cardiovascular diseases. However, the underlying pathological mechanisms are largely unknown. Here, we show a novel toxic mechanism of TFAs triggered by DNA damage. We found that elaidic acid (EA) and linoelaidic acid, major TFAs produced during industrial food manufacturing (so-called as industrial TFAs), but not their corresponding cis isomers, facilitated apoptosis induced by doxorubicin. Consistently, EA enhanced UV-induced embryonic lethality in C. elegans worms. The pro-apoptotic action of EA was blocked by knocking down Sab, a c-Jun N-terminal kinase (JNK)-interacting protein localizing at mitochondrial outer membrane, which mediates mutual amplification of mitochondrial reactive oxygen species (ROS) generation and JNK activation. EA enhanced doxorubicin-induced mitochondrial ROS generation and JNK activation, both of which were suppressed by Sab knockdown and pharmacological inhibition of either mitochondrial ROS generation, JNK, or Src-homology 2 domain-containing protein tyrosine phosphatase 1 (SHP1) as a Sab-associated protein. These results demonstrate that in response to DNA damage, TFAs drive the mitochondrial JNK-Sab-ROS positive feedback loop and ultimately apoptosis, which may provide insight into the common pathogenetic mechanisms of diverse TFA-related disorders.

Association between plasma concentrations of elaidic acid, a major trans fatty acid, and depression in a nationally representative sample of U.S. adults

BackgroundPrevious studies on health effects of trans fatty acids (TFA) have focused mainly on cardiovascular health. Little is known about the association of TFA with brain or mental health. In this study, we examined the associations of objectively-measured plasma TFA concentrations with depression in a large population-based cross-sectional study among U.S. adults. MethodsWe included 2136 non-pregnant participants aged 20 years or older from the National Health and Nutrition Examination Survey 2009–2010. Four major TFAs, including palmitelaidic acid (C16:1n-7t), elaidic acid (C18:1n-9t), vaccenic acid (C18:1n-7t), and linoelaidic acid (C18:2n-6t, 9t), were measured in fasting plasma using gas chromatography/mass spectrometry. Depressive symptoms were assessed using the validated Patient Health Questionnaire-9. ResultsParticipants with depressive symptoms had a higher plasma concentration of total TFA compared with those without depressive symptoms (6.6 vs 6.0 μmol/g lipids, P = 0.046). After adjustment for other major risk factors, the odds ratio (OR) of depressive symptoms comparing the highest with lowest tertile of TFAs was 1.44 (95% CI, 0.86–2.39) for total TFAs (P for trend 0.15). For each individual type of TFA, the corresponding OR was 1.78 (1.03–3.07) for elaidic acid (P for trend 0.049), 1.23 (0.76–2.00) for linoelaidic acid (P for trend 0.37), 1.19 (0.75–1.87) for palmitelaidic acid (P for trend 0.46), and 1.20 (0.75–1.94) for vaccenic acid (P for trend 0.43). LimitationsThe cross-sectional study design limited causal inferences of the findings. ConclusionsIn a nationally representative population, plasma elaidic acid, a major trans fatty acid, was positively associated with depressive symptoms in adults. A positive but non-significant association of depressive symptoms was observed for total TFAs, linolelaidic acid, palmitelaidic acid, and vaccenic acid.

Association between plasma trans-fatty acid concentrations and diabetes in a nationally representative sample of US adults.

A diet high in trans-fatty acids (TFA) induces insulin resistance in rodent models and primates. However, previous epidemiological studies on the association between TFAs, based primarily on self-reported intake from the diet, and diabetes in humans have yielded conflicting results. Herein we examined the associations of objectively measured plasma TFA concentrations with diabetes in a large population-based study among US adults. We included 3801 participants aged ≥20 years from the National Health and Nutrition Examination Survey 1999-2000 and 2009-10. Four major TFAs, namely palmitelaidic acid (C16:1 n-7t), elaidic acid (C18:1 n-9t), vaccenic acid (C18:1 n-7t), and linolelaidic acid (C18:2 n-6t, 9t), were measured in fasting plasma using gas chromatography-mass spectrometry. Diabetes was defined by self-reported physician diagnosis, plasma fasting glucose ≥126 mg/dL, or HbA1c ≥6.5%. After adjustment for other major risk factors, the odds ratios (95% confidence intervals) of diabetes comparing the highest with lowest quintile of plasma TFAs was 2.19 (1.27-3.79) for total TFAs (Ptrend = 0.01), 2.34 (1.48-3.72) for elaidic acid (Ptrend = 0.0004), 1.33 (0.82-2.15) for linolelaidic acid (Ptrend = 0.18), 1.58 (0.97-2.58) for palmitelaidic acid (Ptrend = 0.02), and 1.64 (0.95-2.84) for vaccenic acid (Ptrend = 0.08). In addition, total TFAs, elaidic acid, palmitelaidic acid, and vaccenic acid were significantly associated with fasting glucose, fasting insulin, the insulin resistance index, and HbA1c. In a nationally representative population, plasma TFAs, in particular elaidic acid, were positively associated with diabetes and biomarkers of glucose metabolism.

Association between plasma trans fatty acids concentrations and leucocyte telomere length in US adults.

To assess the relationship between plasma trans-fatty acids (TFAs) levels and leucocyte telomere length (TL) in a US adult population sample. National Health and Nutrition Examination Survey (NHANES) database was used for this study. Gas chromatography was used to separate derivatised fatty acids (Four major TFAs [palmitelaidic acid (C16:1n-7t), trans vaccenic acid (C18:1n-7t), elaidic acid (C18:1n-9t), and linoelaidic acid (C18:2n-6t,9t)]) which were then quatified using negative chemical ionization mass spectrometry. Data analyses used multivariable linear regressions, while accounting for the survey design. A total of 5446 eligible participants, with 46.8% (n = 2550) being men, were included. Their average age was 47.1 years for the total sample, and 47.8 and 46.5 years in men and women respectively (p = 0.085 for men vs. women difference). Concentrations of palmitelaidic acid and linolelaidic acid decreased with increasing length of the telomere (p < 0.05). Univariable linear regressions revealed a significant negative association between levels of the palmitelaidic acid, elaidic acid, vaccenic acid, and linolelaidic acid with TL. However when models were adjusted for age, sex, ethnicity, education, marital status, sub-clinical inflammation, body mass index, and smoking, only palmitelaidic acid and linolelaidic acid remained significant (p < 0.05). TFAs levels and particularly palmitelaidic and linolelaidic acids, are likely negatively associated with telomere lenght. Future studies should explore the potential implications of these associations.

Quantitation of trans-fatty acids in human blood via isotope dilution-gas chromatography-negative chemical ionization-mass spectrometry

Trans-fatty acids (TFA) are geometric isomers of naturally occurring cis-fatty acids. High dietary TFA intake has been associated with risk factors for cardiovascular disease. However, little is known about TFA levels in humans. To address this data need, we developed and validated a new isotope dilution-gas chromatography-negative chemical ionization-mass spectrometry (ID-GC-NCI-MS) method for quantitation of 27 fatty acids (FA) including 4 major TFA in human plasma, serum, and red blood cells (RBC) from 66 donors. Quantitation was performed with 18 isotope labeled internal standards and results are presented in μM and % of total FA. This method has high sensitivity and specificity due to use of pentafluorobenzyl-bromide derivatization combined with NCI-MS and a 200m column to optimize positional and geometric FA isomer separation. The four major TFA, palmitelaidic acid, elaidic acid, trans-vaccenic acid, and linoelaidic acid, were detected in all samples, with median total TFA concentrations of 17.7μM in plasma, 19.6μM in serum, and 21.5μM in RBC. The % of total FA for the TFA was 0.20% in plasma, 0.20% in serum, and 0.30% in RBC. Patterns for % FA are similar to those reported in other studies. We developed a highly specific, ID-GC-NCI-MS method to quantitate TFA and other FA in humans.

Trans fatty acids and conjugated linoleic acid in food: origin and biological properties

Trans fatty acids (TFA) are minor lipid components present in different foods, including ruminant derived products, which have received great attention due to their relationship with cardiovascular disease risk. The origin of TFA in food is mainly related to the industrial hydrogenation processes of unsaturated vegetable oils, but they can also occur naturally in the digestive tract of ruminants by enzymatic biohydrogenation reactions. Both mechanisms generate similar TFA compounds. However, TFA consumption may exert different biological effects depending on the isomeric distribution, which is strongly influenced by the dietary source (i.e., industrial or natural). Industrial hydrogenated vegetable fats are rich in elaidic (trans-9 18:1) and trans-10 18:1 fatty acids, among others. In contrast, vaccenic acid (trans-11 18:1) is the major TFA isomer detected in milk and other ruminant derived products. Vaccenic acid is the physiological precursor of conjugated linoleic acid, a bioactive lipid with beneficial effects on human health. This article provides updated information on the biological effects and potential bioactive properties of TFA considering both, their chemical structure and provenance.

Elaidic acid induces cell apoptosis through induction of ROS accumulation and endoplasmic reticulum stress in SH‑SY5Y cells.

Elaidic acid, which is a major trans fatty acid, has been reported to be involved in neurotoxicity; however, the underlying molecular mechanisms underlying its neurotoxic effects remain largely unknown. Therefore, the present study aimed to investigate the potential mechanisms underlying elaidic acid-induced neuronal damage in vitro. The SH-SY5Y neuroblastoma cell line was used as a model in the present study. Following treatment of cells with various concentrations of elaidic acid or with vehicle for 24 h, cell viability was measured using the MTT assay. Mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) release were measured using flow cytometry. Cell apoptosis was measured by Annexin V-fluorescein isothiocyanate/propidium iodide double staining, and cellular redox status was determined using ELISA analysis. Furthermore, western blotting was used to detect the protein expression levels of factors associated with oxidative damage and components of the endoplasmic reticulum (ER) stress/unfolded protein response (UPR) signaling pathways. The results demonstrated that elaidic acid treatment inhibited cell viability, elevated cell apoptosis and resulted in a loss of MMP. In addition, elaidic acid induced marked alterations in cellular redox status. Treatment with high doses of elaidic acid treatment also enhanced the release of ROS, and upregulated lipid peroxide and malondialdehyde levels; however, it reduced superoxide dismutase and glutathione peroxidase activities. Furthermore, elaidic acid resulted in upregulation of nuclear factor erythroid 2-related factor 2 and downregulation of heme oxygenase 1, which are two key antioxidative factors. Elaidic acid treatment also induced or inhibited the expression of numerous ER stress/UPR-associated molecules. It induced glucose-regulated protein 78 (GRP78) expression, whereas the expression levels of activating transcription factor 4 (ATF4) and CCAAT/enhancer-binding protein homologous protein (CHOP) were upregulated and then downregulated following treatment with various doses of elaidic acid. These results indicated that elaidic acid inhibited SH-SY5Y cell growth and induced apoptosis by enhancing oxidative stress and activating the ER stress/UPR signaling pathway and the GRP78/ATF4/CHOP pathway.

The association between fatty acid index and in vitro fertilization outcomes

Fatty acids have been shown to play an important role in oocyte competence and early implantation of the embryo. Our hypothesis-generating study sought to determine if individual fatty acids expressed as a percentage of total erythrocyte fatty acids are associated with embryo quality and other in vitro fertilization (IVF) outcomes. This was a prospective cohort study at an academic fertility center. Sixty women undergoing their first IVF cycle were recruited. Serum measurements of 22 fatty acids were obtained. We calculated each fatty acid as a percentage of total fatty acids, defined as the index for that individual fatty acid. Omega-3 index had no correlation with IVF outcomes. A negative correlation was found between the trans fatty acid index, elaidic acid (EA), and IVF outcomes, including fertilization rate (r=-0.261, p=0.04), blastocyst conversion rate (r=-0.41, p=0.001), and number of usable blastocysts and embryos (r=-0.411, p=0.001). There was no correlation between EA index and number of oocytes retrieved, embryo grade, or clinical pregnancy. No consistent correlations were observed with the additional fatty acids analyzed. No correlation was observed between omega-3 index and IVF outcomes. Elevated erythrocyte EA index, the major trans fatty acid commonly consumed in hydrogenated oils, margarine, and fried foods, was negatively correlated with number of usable blastocysts and embryos, blastocyst conversion, and fertilization rate. Our findings suggest preliminary evidence that trans fat may be negatively associated with IVF outcomes.

The impact of serum trans fatty acids concentration on plaque vulnerability in patients with coronary artery disease: Assessment via optical coherence tomography

Background and aimsRecent epidemiological studies have showed that excessive intake of trans fatty acids (TFA) can be a residual risk for the development of coronary artery disease (CAD) even under medical management, including statins. This study aimed at investigating the association between lipid profile, including serum TFA concentration, and plaque vulnerability using optical coherence tomography (OCT). MethodsThe level of serum elaidic acid, a major TFA component, was measured using gas chromatography in 161 consecutively enrolled patients with CAD under guideline-directed risk factor management. OCT was performed to evaluate morphological features of angiographic intermediate stenosis (30% < diameter of stenosis <70%). OCT data were also used to measure lipid index (LI), defined as mean lipid arc multiplied by lipid length, and determine the presence of thin-cap fibroatheroma (TCFA), defined as a lipid-rich plaque with the smallest fibrous cap thickness <65 μm and the maximal arc >90°. ResultsAmong 190 lesions assessed using OCT, 49 TCFAs were detected. In patients with at least one TCFA lesion, levels of elaidic acid (12.9 ± 4.9 vs. 10.3 ± 4.3 μmol/L, p = 0.001), triglycerides (169 ± 81 vs. 130 ± 60 mg/dL, p = 0.005), and remnant-like particle cholesterol (10.4 ± 6.5 vs. 7.7 ± 4.7 mg/dL, p = 0.005) were higher than in those without TCFAs. Generalized estimating equations identified elaidic acid level as the independent risk factor of TCFA. LI had a positive correlation with elaidic acid level (r = 0.173, p = 0.025). ConclusionsTFA may affect plaque vulnerability in patients with CAD. Serum TFA concentration may represent another cardiovascular risk factor during conventional risk factor management.

Effect of rice bran oil spread on the physical, sensory and fatty acid profile of cake.

Studies were carried out to replace hydrogenated fat (HF) with rice bran oil (RBO) and two varieties of rice bran oil spread RBOS1 and RBOS2 in the preparation of cake. Physico-chemical properties, sensory properties, scanning electronic microscopic (SEM) study and fatty acid estimation with reference to trans fatty acids of cake made with control and experimental samples were studied. The best acceptable cake among the four i.e., RBOS2 cake was selected for consumer evaluation along with control (HF) cake. Results revealed that there was no significant difference in overall acceptability of cake made with HF and RBOS2. The internal structure and pore structure of RBOS2 cake was finer and smoother than the control cake as per SEM imaging. The pores within the core varied in diameter between 13.9 and 29.6µm in control cake and between 16.9 and 58.6µm in RBOS2 cake at 500×magnification indicating good textural properties compared to HF cake. The fatty acids analysis results showed that the amount of total trans fatty acids (TFA) was 15.46% in HF cake, 3.56% in RBO cake, 4.54% in RBOS1 cake, and 3.78% in RBOS2 cake. The major trans fatty acids observed in all samples were elaidic acid (C18:1 trans-9) and Linolelidic acid (C18:2, trans-6). Elaidic acid was the highest in HF cake (6.64%) and the least in RBO cake (2.62%). Linolelidic acid was the highest in HF cake (8.48%) and the least in RBOS2 cake (0.91%). Trans Vaccenic acid was detected only in HF cake (0.34%). TFA content assumes significance in terms of its ill effects on the health of consumers, only if fat content is also high. Hence, consumption of the HF products might prove to be harmful, if consumed in large amounts and at higher frequencies. Therefore RBOS can be promoted as healthy fat for production of baked products.

Plasma trans-fatty acid concentrations in fasting adults declined from NHANES 1999–2000 to 2009–20101–3

Background: The consumption of trans fatty acids (TFAs) is associated with an increased risk of cardiovascular disease, and reducing their consumption is a major public health objective. Food intake studies have provided estimates for TFA concentrations in the US population; however, there is a need for data on TFA blood concentrations in the population.Objective: The objective of this study was to determine plasma TFA concentrations in a nationally representative group of fasted adults in the US population in NHANES samples from 1999–2000 and 2009–2010.Design: Four major TFAs [palmitelaidic acid (C16:1n–7t), trans vaccenic acid (C18:1n–7t), elaidic acid (C18:1n–9t), and linoelaidic acid (C18:2n–6t,9t)] were measured in plasma in 1613 subjects from NHANES 1999–2000 and 2462 subjects from NHANES 2009–2010 by gas chromatography–mass spectrometry. Geometric means and distribution percentiles were calculated for each TFA and their sum by age, sex, and race/ethnicity (non-Hispanic white, non-Hispanic black, Mexican American), and covariate-adjusted geometric means were computed by using a model that included these demographic and other dietary factors, as well as survey year and any significant interaction terms.Results: These nationally representative data for the adult US population show that TFA concentrations were 54% lower in NHANES 2009–2010 than in NHANES 1999–2000. Covariate-adjusted geometric means for the sum of the 4 TFAs were 81.4 μmol/L (95% CI: 77.3, 85.6 μmol/L) and 37.8 μmol/L (95% CI: 36.4, 39.4 μmol/L) in NHANES 1999–2000 and 2009–2010, respectively. Even with the large decline in TFA concentrations, differences between demographic subgroups were comparable in the 2 surveys.Conclusion: The results indicate an overall reduction in TFA concentrations in the US population and provide a valuable baseline to evaluate the impact of the recent regulation categorizing TFAs as food additives.

Concerns about the use of 15:0, 17:0, and trans-16:1n–7 as biomarkers of dairy fat intake in recent observational studies that suggest beneficial effects of dairy food on incidence of diabetes and stroke

Concerns about the use of 15:0, 17:0, and trans-16:1n–7 as biomarkers of dairy fat intake in recent observational studies that suggest beneficial effects of dairy food on incidence of diabetes and stroke

Trans Fatty Acids in Plasma, Serum, and Red Blood Cells

Trans‐fatty acids (TFA) intake was associated with increased risk of cardiovascular disease. However, little is known about TFA concentrations in human blood. Studies suggested that individuals with the same fatty acid (FA) intake may have different concentrations of regular FA in red blood cells (RBC), plasma, and serum due to a number of factors including genetics and lifestyle. This created the need to assess TFA concentrations in different blood specimens from people to obtain information about TFA exposure and metabolism. We investigated the TFA distribution in RBC, plasma, and serum using convenience samples from 66 adults. Samples were analyzed using an isotope dilution‐gas chromatography‐mass spectrometry method validated for the analysis of 28 FA, including the 4 major TFA: palmitelaidic acid, elaidic acid, vaccenic acid, and linoelaidic acid. The TFAs were detected in all samples, with median total TFA concentrations of 21.12 μM in RBC, 17.86 μM in plasma, and 20.88 μM in serum. The median percent of total TFA was similar for elaidic and vaccenic acids in all three matrices. The median percent of total TFA was 1/3 lower in the RBC than in the plasma and serum for palmitelaidic acid and half as high for linoelaidic acid in RBC as in plasma and serum. The differences in TFA distributions suggest differences in metabolism of individual TFA.

The trans fatty acid content in human milk and its association with maternal diet among lactating mothers in Malaysia.

Excessive intake of trans fatty acids (TFA) could reduce the fat density of human milk and impair the desaturation of essential fatty acids. Because the mammary glands are unable to synthesize TFA, it is likely that the TFA in human milk come from dietary intake. Thus, the aim of this study was to investigate the sources of TFA intake for lactating mothers in one of the urban areas in Selangor. In this cross-sectional study, anthropometric measurements, FFQ including 7 food groups and dietary consumption data were collected from 101 lactating mothers. Five major TFA isomers (palmitoelaidic acid (16:1t9), petroselaidic acid (18:1t6), elaidic acid (18:1t9), vaccenic acid (18:1t11) and linoelaidic acid (18:2t9,12) in human milk were measured by gas chromatography (GC). The relationship between food consumption and TFA levels was assessed using the non-parametric Spearman's rho test. The TFA content in human milk was 2.94±0.96 (SEM) % fatty acid; this is considered low, as it is lower than 4%. The most abundant TFA isomer was linoelaidic acid (1.44±0.60% fatty acid). A sub-experiment (analyzing 3 days of composite food consumption) was conducted with 18 lactating mothers, and the results showed that linoelaidic acid was the most common TFA consumed (0.07±0.01 g/100 g food). Only 10 food items had an effect on the total TFA level and the isomers found in human milk. No association was found between TFA consumption and the TFA level in human milk.

Linolelaidic Acid Induces a Stronger Proliferative Effect on Human Umbilical Vein Smooth Muscle Cells Compared to Elaidic Acid

Trans fatty acids (TFA) have been considered as an independent risk factor of coronary heart disease, sudden death and insulin-resistance, and different TFA isomers may have different effects on the progression of cardiovascular diseases such as atherosclerosis. The aim of the study was to investigate the effects of two major TFA, elaidic acid and linolelaidic acid which have the same number of carbons but a different number and configuration of trans bonds, on the proliferation of human umbilical vein smooth muscle cells (HUVSMC). Methyl thiazolyl tetrazolium and flow cytometry assays showed that the cell proliferation rose to 115.37±0.39 and 117.5±0.57% and the cell number in the S phase of the cell cycle reached 27.7±0.7 and 25.8±2.8% when treated with 50μM elaidic acid and 20μM linolelaidic acid, respectively. Quantitative real-time reverse transcriptase-polymerase chain reaction and Western blotting analyses showed that the two TFA increased the mRNA and protein expression levels of PCNA, CDK2 and Cyclin E in HUVSMC. Moreover, gas chromatography analysis showed that the total PUFA level of HUVSMC was lower after treatment with the two TFA, especially n-3 PUFA. These results suggested that linolelaidic acid exhibited a stronger proliferative effect on HUVSMC than elaidic acid, and regulation of CDK2 and Cyclin E may be important for the effect of the TFA on atherosclerosis.

Trans Fatty Acid Content of Iranian Edible Oils

Clinical and epidemiologic studies showed that among dietary factors the type of fatty acids (FAs) in the diet plays an important role in determining risk of chronic disease. The aim of our study was to determine the levels of Trans FA (TFA) in edible oil samples consumed in Tehran, Iran analyzed by gas chromatograph (GC). The mean of total TFA was 0.45% ranging from (0.11% - 1.61%) for liquid frying oils and 2.92% ranging from (0.46% - 5.40%) for solid oils. The major TFA observed in these two groups was elaidic acid in solid oils. The highest content of total saturated fatty acid (SFA) was detected in solid oils with average of 32.07 and palmitic acid was the major SFA in these four groups. Linoleic and linolenic acid are the most important poly unsaturated fatty acid (PUFA). The variance in the percentage of TFA in the edible oils probably resulted from differences in the type of oils, quality, heating, processing technique and storage condition of the edible oils. The results indicated that, edible oils contain considerable proportions of trans fatty acids. Therefore, it is important to assess the content of TFA in edible oils in Iran.

Formation of Trans Fatty Acids Induced by Radicals in Irradiated Ground Beef and Liquid Egg

AbstractThis study was conducted to investigate the possible formation of trans fatty acids due to gamma‐irradiation of ground beef and liquid egg via a radical path. The effects of irradiation on trans fatty acids in ground beef and liquid egg were evaluated by GC analysis. The control sample of ground beef had higher concentrations of total trans fatty acids than the liquid egg. C18:1‐11t was the major trans fatty acid detected in non‐irradiated ground beef. The results showed that irradiation led to a significant increase of total trans fatty acid content in both of the two food items with an absorbed dose range between 6.743 and 11.472 kGy (P &lt; 0.05). The change in C18:1‐9t content was the most significant compared with other trans fatty acids. Additionally, gamma‐irradiation caused a higher rate of trans fatty acid formation in liquid egg compared with ground beef. However, a slight decrease in the total trans fatty acid amount was observed in ground beef with an absorbed dose at 21.113 kGy. The increase in trans fatty acid content was negligible in liquid egg under the same absorbed dose. This result may be due to the oxidation of unsaturated configurations of both cis and trans fatty acids.

Substitution of wheat dried distillers grains with solubles for barley silage and barley grain in a finishing diet increases polyunsaturated fatty acids including linoleic and alpha-linolenic acids in beef

Wheat dried distillers grain with solubles (WDDGS) contain low levels of starch, but are high in protein and fiber and have been used as a substitute for barley grain in commercial Western Canadian finishing diets for beef cattle. This study investigated effects of WDDGS on fatty acid profiles of meat when it was substituted for barley silage in a barley grain finishing diet. Steers (n=240; 489±30.0kg) were fed one of four finishing diets consisting of a barley based concentrate (barley grain plus additives), barley silage and WDDGS (dry matter (DM) basis) in ratios of 850:150:0 (CON), 650:100:250 (WDDG25), 650:50:300 (WDDG30), and 650:0:350 (WDDG35) over a 12wk period. Substitution of WDDGS for barley silage increased (P<0.01) concentrations of total polyunsaturated fatty acids (PUFA), including linoleic acid and alpha-linolenic acid (ALA) in pars costalis diaphragmatis muscle without affecting major trans fatty acids. Replacement of 100 and 150g silage with 200g of barley grain/kg feed DM with WDDGS increased (P<0.05) ALA, from 0.32g in CON to 0.40 and 0.41g/kg of total fatty acids in WDDG30 and WDDG35, respectively. Results suggest that replacement of barley silage with up to 350g WDDGS/kg DM increases total PUFA and omega-3 fatty acids in beef.