Monounsaturated Fatty Acid Composition Research Articles

Effect of daily avocado consumption for 6 mo compared with habitual diet on red blood cell fatty acid profiles and association with cardiometabolic risk factors in individuals with abdominal obesity: a randomized trial

BackgroundAvocado intake improves dietary fat quality, but the subsequent impact on red blood cell (RBC) saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA), and trans-fatty acid (TFA) composition and association with cardiometabolic health, has not been elucidated. ObjectivesTo compare the effect of consuming 1 avocado/d relative to habitual diet (HAB) on RBC-FA profiles, and their association with visceral adiposity and cardiometabolic risk factors (CMRFs) in individuals with abdominal obesity. MethodsRBC-FA profiling at baseline, 3- and 6 mo was conducted in participants (n = 994) from the Habitual Diet and Avocado Trial (HAT). HAT was a multisite, free-living, parallel-arm intervention study in which participants were randomly assigned to either the avocado-supplemented group (AVO, usual diet with 1 avocado/d) or the HAB group (usual diet with limited avocado intake) for 6 mo. Changes in RBC-FA profiles, a secondary outcome measure, were determined within and between groups using linear regression and mixed effect models, adjusting for age, sex, BMI, clinical site, smoking status, and percentage of energy intake from fat at baseline. The association between changes in RBC-FAs with visceral adiposity measures and CMRFs was assessed after covariate and False Discovery Rate (FDR <0.05) adjustment. ResultsNo major differences in RBC-FA profiles were observed between groups, with the exception of MUFA cis-vaccenic [18:1n−7c], which was significantly higher in AVO (β: 0.11 [0.05, 0.17]) compared with the HAB (β: 0.03 [−0.03, 0.08]) participants. In the HAB but not AVO group, increases in MUFA cis (18:1n−7c, oleic [18;1n−9c], erucic [22:1n−9c]) and MUFA trans (palmitelaidic [16:1n−7t], vaccenic [18:1n−7t], elaidic [18:1n−9t], and petroselaidic [18;1n−10-12t), as well as PUFA γ-linolenic [18:3n−6], dihomo-γ-linolenic [20:3n−6], arachidonic [20:4n−6], and α-linolenic [18:3n−3] were associated with unfavorable changes in visceral adiposity measures, lipid profiles, glucose, insulin and high sensitivity C-reactive protein concentrations. ConclusionsDaily avocado intake over 6-mo modified RBC–MUFA composition, notably 18:1n−7c, and potentially mitigated some of the unfavorable individual RBC-FA–CMRF associations observed over time in the HAB group.This trial was registered at https://clinicaltrials.gov/study as NCT03528031.

The composition of monounsaturated fatty acids of artemia enriched with biologically active substances

The work is devoted to the study of monounsaturated fatty acids (MUFA) content in artemia enriched with biologically active substances at different stages of ontogenesis. Artemia cysts are used in the preparation of dietary supplements, highly effective feed additives for farm animals, fertilizers for crop production, chitosan for pharmaceutical industry and cosmetology, as raw materials in many other fields. When growing fish, crustaceans, shellfish in aquaculture, artemia nauplii are used as live starter feeds, which are obtained in situ when cultivating artemia cysts. Recently, the direction of enrichment of artemia nauplia used for feeding fish larvae and fry with biologically active substances has begun to develop: vitamins, essential amino acids, essential fatty acids, probiotics. In our work, we used a feed additive for the enrichment of artemia nauplia, including: vitamin-amino acid complex – «Chiktonic», probiotic – «Vetom-1», adaptogen – «Trekrezan», hemp oil. Enrichment was carried out through the skin at the stage of early nauplia. The aim of the work was to study the composition of MUFA at different stages of ontogenesis in intact artemia and artemia enriched with biologically active substances. The main function of MUFA is to activate metabolic processes and maintain homeostasis. When identifying monounsaturated fatty acids of artemia, the race we studied, the following were identified: oleic, palmitoleic, eicosenic, elaidic, erucic, nervonic, myristoleic acids. Oleic, palmitoleic and eicosenic fatty acids played a dominant role in the structure of MUFA. Two fatty acids, erucic and elaidic, can be distinguished in the composition of MUFA, the content of which was minimal.

Effects of Maternal Exclusion Diet for Infants Suspected Food Allergy on Fatty Acid Composition in Breast Milk

Background: Levels of fatty acid (FA) in breast milk (BM) may vary depending on the maternal diet. This study aimed to explore FA composition in BM of lactating women following dietary restrictions due to infant allergic conditions. Materials and Methods: Thai lactating mothers of term infants who were on exclusion diets were recruited. Mature BM was collected before and after a period (at least 2 weeks) of dietary restriction. FA in BM was analyzed by gas chromatography-mass spectrometry. Results: Fifty lactating women 33.7 ± 3.6 years of age were enrolled. Thirty-three percent of the lactating mothers restricted more than eight food items. Most common dietary restriction were cow's milk (88%) and eggs (74%). After the period of dietary exclusion, total polyunsaturated FA showed no significant change, while saturated FA (SFA) declined, and monounsaturated FA (MUFA) increased. A decrease in fat intake was associated with an increase in arachidonic acid (ARA) and docosahexaenoic acid (DHA) content in BM (r = -0.37, r = -0.36; p < 0.05). However, a rise in ARA, eicosapentaenoic acid (EPA), and DHA intake was associated with an increase in linoleic acid and EPA in BM, respectively (r = 0.38, r = 0.55 and r = 0.41; p < 0.05). Infant weight-for-age z-score did not significantly change after the period of maternal dietary exclusion. Conclusion: Maternal exclusion diet resulted in lower SFA and higher MUFA composition in BM. Further study should explore the long-term outcomes of maternal dietary restriction on infant and child health.

Gökkuşağı Alabalık (Oncorhynchus mykiss Walbaum, 1792) Kıyması ile Üretilmiş Geleneksel Türk İçli Köftesinin Besinsel Komposizyonu ve Dondurularak Depolama Boyunca (-18ºC) Renk ve Duyusal Kalitesinin Belirlenmesi

The nutritional value of stuffed meatballs made with minced rainbow trout rather than red meat in the stuffing was investigated, as well as color variations (L *, a *, and b *) and sensory quality, using two different cooking methods (boiling and frying) on samples stored in the freezer (-18 oC). As a result of this research, the moisture, the crude ash, the lipid, and the crude protein contents of stuffed meatballs produced with rainbow trout were found as %58.25 ± 0.93, %2.01 ± 0.05, %5.28 ± 0.29, and %7.69± 0.08, respectively. The content of total saturated fatty acids composition (∑SFA), total monounsaturated fatty acids composition (∑MUFA), and total polyunsaturated fatty acids composition (∑PUFA) was found to be 12.52 ± 0.23%, 39.11 ± 1.27%, and 43.73 ± 1.98%, respectively. The atherogenic (AI) and thrombogenic indexes (TI) for dietary factors associated with cardiovascular disease were found to be 0.10 and 0.25, respectively. In the evaluation of color (L *, a *, and b *) of frozen samples, L * (black-white) and b * (blue-yellow) values in all groups (raw, boiled, and fried) increased significantly at the end of storage compared to the initial value ( p&amp;lt;0.05). Following frying and boiling, the * (green-red) values of the frozen-stored samples decreased significantly (p&amp;lt;0,05). Sensory quality was assessed in this study using two cooking methods: boiling and fried, both of which are common serving methods for stuffed meatballs. Although a significant decrease was detected in all sensory quality parameters of samples during frozen storage, it was determined that it did not reach the unacceptable limit at the end of storage.

Fatty acid profile in the breast and thigh muscles of the slow- and fast-growing birds under the same management system.

The aim of the study was to assess the effect of feeding the same diet to different breeds of chickens and at different ages on fatty acid (FA) composition of the breast and thigh muscles. A total of 150 chickens comprising 50 each of red jungle fowl (RJ) and village chicken (VC), the slow-growing birds, and the commercial broiler (CB), fast-growing birds, were used for this study. Ten chickens from each breed were serially euthanized at days 1, 10, 20, 56, and 120 post hatch, and pectoralis major and bicep femoris were harvested to represent the breast and thigh muscles respectively. It was revealed that the breast muscle concentrations of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and total polyunsaturated fatty acids (PUFA) are significantly different (p<0.05) among the breeds. Also, the FA composition of breast and thigh muscles among RJ, VC, and CB at various ages studied varied significantly (p<0.05) but without a definite pattern. The composition of MUFA was lower, but that of PUFA was higher in the RJ and VC than in the CB breast muscles. Within the breeds, the composition of total MUFA decreased, while that of PUFA increased with age. The total MUFA and PUFA showed no significant difference (p>0.05) between the breast and thigh muscles at different ages evaluated. This study suggests that slow-growing birds (RJ and VC) might be better sources of desirable FA than the fast-growing birds, CB.

Piglet birthweight and sex affect growth performance and fatty acid composition in fatty pigs

This study aimed to determine the effects of piglet birthweight (BIW) and sex, and within-litter BIW variation, on postnatal growth traits and meat quality in fatty breeds of pig. In total, 406 crossbred piglets (half male, half female) born to Iberian sows were studied during their postnatal development until slaughter. After birth, piglets were classified into four BIW categories: very low, low, medium and high. There was a negative effect of low BIW on growth patterns and fatty acid (FA) composition, but effects of litter size and within-litter BIW variation were not found. The very low BIW piglets underwent a period of significant catch-up growth (P &amp;lt; 0.005) relative to high BIW piglets during the early postnatal phase, but also showed a higher feed conversion rate and lower average daily weight gain (P &amp;lt; 0.05 for both measures) throughout the study period. BIW affected development during the entire productive life, and the sex effect increased with age. As a result, the period to reach market weight was longer in very low BIW piglets, by 43 days for females and 15 days for males, compared with their high BIW counterparts. BIW and sex also influenced amount of intramuscular fat, n-3 FA content and monounsaturated FA composition. The study indicates that BIW, modulated by sex, is a critical point for productive traits in fatty pigs. These results provide a basis for future strategies to enhance productive efficiency and meat quality of traditional swine breeds.

Imaging, Sensory Properties and Fatty Acid Composition of Parma Ham and “Nero Di Parma” Ham

This paper provides preliminary results on “Nero di Parma” ham analysing fatty acid composition from fat and muscle tissues in three locations. Computerized Tomography (CT) and sensory characteristics were also performed. The same measurements were investigated in Parma ham too. Significant differences in terms of saturated and monounsaturated fatty acids composition were observed between hams resulting lower and higher in “Nero di Parma” ham than Parma ham respectively. Results detected by CT showed an inverse ratio of fat and muscle between the hams. “Nero di Parma” ham highlighted some descriptors such as oiliness, brightness, redness significantly different from Parma useful to define the sensory profile of a typical product which had never been tested.

Sodium Orthovanadate Changes Fatty Acid Composition and Increased Expression of Stearoyl-Coenzyme A Desaturase in THP-1 Macrophages

Vanadium compounds are promising antidiabetic agents. In addition to regulating glucose metabolism, they also alter lipid metabolism. Due to the clear association between diabetes and atherosclerosis, the purpose of the present study was to assess the effect of sodium orthovanadate on the amount of individual fatty acids and the expression of stearoyl-coenzyme A desaturase (SCD or Δ9-desaturase), Δ5-desaturase, and Δ6-desaturase in macrophages. THP-1 macrophages differentiated with phorbol 12-myristate 13-acetate (PMA) were incubated in vitro for 48 h with 1 μM or 10 μM sodium orthovanadate (Na3VO4). The estimation of fatty acid composition was performed by gas chromatography. Expressions of the genes SCD, fatty acid desaturase 1 (FADS1), and fatty acid desaturase 2 (FADS2) were tested by qRT-PCR. Sodium orthovanadate in THP-1 macrophages increased the amount of saturated fatty acids (SFA) such as palmitic acid and stearic acid, as well as monounsaturated fatty acids (MUFA)—oleic acid and palmitoleic acid. Sodium orthovanadate caused an upregulation of SCD expression. Sodium orthovanadate at the given concentrations did not affect the amount of polyunsaturated fatty acids (PUFA) such as linoleic acid, arachidonic acid, eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA). In conclusion, sodium orthovanadate changed SFA and MUFA composition in THP-1 macrophages and increased expression of SCD. Sodium orthovanadate did not affect the amount of any PUFA. This was associated with a lack of influence on the expression of FADS1 and FADS2.

FATTY ACIDS CONTENT IN UNGURAHUA OIL (OENOCARPUS BATAUA) FROM ECUADOR. FINDINGS ON ADULTERATION OF UNGURAHUA OIL IN ECUADOR

Objective: The aim of this study was to determine the fatty acids composition in an ungurahua seeds oil (Oenocarpus bataua) sample cultivated in Ecuador and to determine eventual adulteration in the composition of commercial ungurahua oil.Methods: Oil was obtained from ungurahua seeds using the cold pressing method. Fatty acids analysis was performed using the gas chromatography (GC) method with a mass selective detector and using the database library NIST14.L to identify the compounds.Results: Methyl esters fatty acids were identified from ungurahua (O. bataua) using the GC mass spectrometer analytical method. Ungurahua oil presented a high content of monounsaturated fatty acids with 82.03% of oleic acids. A fraud in the composition of fatty acids present in commercial ungurahua oil was found as fatty acids had a value of only 36.77% of oleic acids. The content of linoleic acid can be used to determine adulteration of this oil.Conclusions: Ungurahua seeds are a good source of monounsaturated and fatty acids. The content of oleic acid is higher than in olive oil. Ungurahua can help reducing cardiovascular diseases risk in Ecuador due to its good composition of monounsaturated fatty acids. Ungurahua oil is a good option to be used in the food industry for different uses.

Monitoring the Oxidative Stability of Monovarietal Extra Virgin Olive Oils by UV–Vis Spectroscopy and MCR–ALS

The extra virgin olive oil (EVOO) has a certain oxidation resistance when compared to other vegetable oils without refining process, due to their large composition of monounsaturated fatty acids, antioxidants, and bio-compounds. The main of this research was to evaluate and monitor the behavior of autoxidative processes through the storage time in two packaging systems of different EVOO monovarietals produced in Minas Gerais, Brazil by using ultraviolet and visible spectroscopy (UV–Vis) with multivariate curve resolution with alternating least squares (MCR–ALS). We analyzed six EVOOs produced from different monovarietals (Arbequina, Empeltre, Coratina, Grappolo, Koroneiki, and Maria da Fe), over the course of 1 year, performed the analysis in times 0, 30, 90, 180, and 365 days, and storage in glass bottles and tinplate cans. The UV–Vis spectroscopy coupled with MCR–ALS was a feasible tool to monitor autoxidation processes in EVOO through storage time and in the monitoring of the EVOO quality in different package systems. The glass bottles were a package system that provides more protection for the autoxidation processes with the time for the EVOO from monovarietals Empeltre, Arbequina, and Coratina. In addition, it was possible to make a differentiation between the monovarietal olive oils produced in Brazil by observing the amount of phenolic compounds present in the chemical composition of each oil. Allowing gather information about the formation of oxidative products may correlate with the shelf life of the EVOO.

Comparison of lipid and biodiesel properties of Chaetoceros muelleri cultured in deep sea water and surface sea water

The growth rates, lipid characteristics, and fuel properties of fatty acid methyl esters (FAME) made from the microalgae cultured in deep sea water (DSW) were analyzed and compared with those made from the microalgae cultured in surface sea water (SSW). The mineral nutrients including nitrates, silicates, and phosphates contained in DSW were, respectively, 7.8, 4.6, and 5.2 times than those of the corresponding nutrients in SSW. The experimental results also show that the lipid content, growth rate, biomass formation, and production of fatty acid methyl ester (FAME) of the microalgae cultured in DSW were significantly greater than those of the microalgae cultured in SSW by 23.0%, 120.0%, 4.7%, and 9.5%, respectively. In addition, the microalgae cultured in DSW took additional 2 days to reach their maximum biomass quantity than those cultured in SSW. Biodiesel made from Chaetoceros muelleri grown in DSW had the highest content of saturated fatty acids and the lowest composition of mono-unsaturated fatty acids and iodine number among those three biodiesels studied here. DSW is thus a favorable medium for microalgae cultivation to generate lipid and biodiesel with adequate fuel properties.

Rapid, non-destructive determination of butter adulteration by means of photopyroelectric (PPE) calorimetry

The study focuses on the application of the photopyroelectric (PPE) technique combined with gas chromatography to detect adulteration of cow milk-obtained butter. The thermal diffusivity and effusivity have been directly measured using back and front PPE detection, respectively, and the results have been correlated with the composition of adulterated butter samples. The back detection configuration has been used in the case of butter adulterated with palm oil, and a possible correlation of the thermal diffusivity with total amount of monounsaturated fatty acids composition has been proposed. For butter adulterated with soy milk, we used the front PPE configuration in order to measure the samples’ thermal effusivity. A strong dependence of the value of thermal effusivity as a function of soy milk content was found.

Critical role of miR-125b in lipogenesis by targeting stearoyl-CoA desaturase-1 (SCD-1)1

Alteration of gene expression tightly regulates lipogenesis. Stearoyl-CoA desaturase-1 (SCD-1), a key enzyme in lipogenesis, catalyzes the conversion of SFA to MUFA, and inhibition of its activity impairs lipid synthesis. As posttranscriptional regulators, microRNAs are involved in many pathways of lipid metabolism; however, their effect on SCD-1 has not been reported. In this study, miR-125b was identified as a potential regulator of SCD-1 using bioinformatics analysis. Here, we validated SCD-1 as the target of miR-125b using a dual luciferase assay. During adipogenesis, a synthetic mimic or inhibitor was used to overexpress or reduce the expression of miR-125b in porcine adipocytes. Overexpression of miR-125b reduced the accumulation of lipid droplets and triglycerides concentration and repressed SCD-1 protein expression and MUFA composition. The inhibitor had the reverse effect. Small interfering RNA against tested in adipocytes further proved the direct correlation between miR-125b and SCD-1. Moreover, in vivo experiments in mice showed that injection of miR-125b expression vector decreased the hepatic triglycerides concentration relative to saline. This study indicated that miR-125b regulates lipogenesis by targeting SCD-1; therefore, miR-125b might be applied in therapy of lipid metabolism disorders.

Microbial lipid production by cold‐adapted oleaginous yeast Yarrowia lipolytica B9 in non‐sterile whey medium

AbstractDeproteinized whey was used as a substrate for the production of lipids by cold‐adapted yeast Yarrowia lipolytica B9 under non‐sterile culture conditions. Undesired microbial contamination in non‐sterile whey medium could be prevented when appropriate culture parameters (inoculum size of 3 mL/100 mL, initial pH of 5.5 and incubation temperature of 15 °C) were selected. In contrast to additional nitrogen (ammonium sulfate) and phosphorus (potassium dihydrogen phosphate) sources, additional carbon source (lactose) increased lipid accumulation. Under optimized culture conditions, biomass and lipid concentrations of the yeast were found as 7.4 g/L and 4.29 g/L, respectively. Lipid content was determined as 58% of total cell biomass. Fatty acids of the yeast were oleic acid (18:1), cis‐10‐heptadecenoic acid (C17:1), palmitoleic acid (16:1) and palmitic acid (16:0). The yeast was found to contain no polyunsaturated fatty acids. The content of C16 and C18 fatty acids was found to be 91.98% of total lipids. Monounsaturated fatty acids accounted for 80.54% of total lipids. Due to rich monounsaturated fatty acid composition, biomass of Y. lipolytica B9 may be used as feedstock for biodiesel production, especially operating in winter conditions. This is the first report on the use of cheese whey as a lipid production substrate for cold‐adapted microorganisms including Y. lipolytica yeast. Besides, lipid production potential of Y. lipolytica under non‐sterile culture conditions was investigated for the first time in this study. © 2015 Society of Chemical Industry and John Wiley &amp; Sons, Ltd

Transcriptional analysis of intramuscular fatty acid composition in the longissimus thoracis muscle of Iberian × Landrace back‐crossed pigs

This study aimed at identifying differential gene expression conditional on the fatty acid profile of the longissimus thoracis (Lt) muscle, a prime cut of economic relevance for fresh and cured pork production. A population of 110 Iberian (25%)×Landrace (75%) back-crossed pigs was used, because these two breeds exhibit extreme profiles of intramuscular saturated fatty acid, monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) contents. Total RNA from Lt muscle was individually hybridized to GeneChip Porcine Genome arrays (Affymetrix). A principal component analysis was performed with data from the 110 animals to select 40 extreme animals based on the total fatty acid profile and the MUFA composition (MAP). Comparison of global transcription levels between extreme fatty acid profile pigs (n=40) resulted in 219 differentially expressed probes (false discovery rate <0.10). Gene ontology, pathway and network analysis indicated that animals with higher percentages of PUFA exhibit a shift toward a more oxidative muscular metabolism state, with a raise in mitochondria function (PPARGC1A, ATF2), fatty acid uptake and oxidation (FABP5, MGLL). On the other hand, 87 probes were differentially expressed between MUFA composition groups (n=40; false discovery rate <0.10). In particular, muscles rich in n-7 MUFA expressed higher levels of genes involved in lipid metabolism (GLUL, CRAT, PLA2G15) and lower levels of fatty acid elongation genes (ELOVL5). Moreover, the chromosomal position of FABP5, PAQR3, MGLL, PPARGC1A, GLUL and ELOVL5 co-localized with very relevant QTL for fat deposition and composition described in the same resource population. This study represents a complementary approach to identifying genes underlying these QTL effects.

Hepatic and plasma sex differences in saturated and monounsaturated fatty acids are associated with differences in expression of elongase 6, but not stearoyl-CoA desaturase in Sprague–Dawley rats

Monounsaturated fatty acids (MUFA) have been viewed as either beneficial or neutral with respect to health; however, recent evidence suggests that MUFA may be associated with obesity and cardiovascular disease. Sex differences in MUFA composition have been reported in both rats and humans, but the basis for this sexual dimorphism is unknown. In the current study, enzymes involved in MUFA biosynthesis are examined in rat and cell culture models. Male and female rats were maintained on an AIN-93G diet prior to killing at 14weeks of age after an overnight fast. Concentrations of 16:0 (2,757±616 vs. 3,515±196μg fatty acid/g liver in males), 18:1n-7 (293±66 vs. 527±49μg/g) and 18:1n-9 (390±80 vs. 546±47μg/g) were lower, and concentrations of 18:0 (5,943±1,429 vs. 3,987±325μg/g) were higher in phospholipids in livers from female rats compared with males. Hepatic elongase 6 mRNA and protein were 5.9- and 2.0-fold higher, respectively, in females compared with males. Stearoyl-CoA desaturase expression did not differ. Specific hormonal effects were examined in HepG2 cells cultured with varying concentrations of 17β-estradiol, progesterone and testosterone (0, 10, 30 and 100nM) for 72h. Progesterone and 17β-estradiol treatments increased, while testosterone decreased, elongase 6 protein. Sex differences in MUFA composition were associated with increased expression of hepatic elongase 6 in females relative to male rats, which appears to be mediated by sex hormones based on observations of hormonal treatments of HepG2 cells.

Omega-3 fatty acid deficiency increases stearoyl-CoA desaturase expression and activity indices in rat liver: Positive association with non-fasting plasma triglyceride levels

Although omega-3 ( n−3) fatty acids negatively regulate triglyceride biosynthesis, the mechanisms mediating this effect are poorly understood, and emerging evidence suggests that stearoyl-CoA desaturase (Scd1) is required for de novo triglyceride biosynthesis. To investigate this mechanism, we determined the effects of perinatal n−3 deficiency and postnatal repletion on rat liver Scd1 mRNA expression and activity indices (liver 16:1/16:0 and 18:1/18:0 ratios), and determined relationships with postprandial (non-fasting) plasma triglyceride levels. Rats were fed conventional diets with or without the n−3 fatty acid precursor α-linolenic acid (ALA, 18:3 n−3) during perinatal development (E0-P100), and a subset of rats fed the ALA− diet were switched to the ALA+ diet post-weaning (P21-P100, repletion). Compared with controls, rats fed the ALA− diet exhibited significantly lower liver long-chain n−3 fatty acid compositions and elevations in monounsaturated fatty acid composition, both of which were normalized in repleted rats. Liver Scd1 mRNA expression and activity indices (16:1/16:0 and 18:1/18:0 ratios) were significantly greater in n−3 deficient rats compared with controls and repleted rats. Among all rats, liver Scd1 mRNA expression was positively correlated with liver 18:1/18:0 and 16:1/16:0 ratios. Plasma triglyceride levels, but not glucose or insulin levels, were significantly greater in n−3 deficient rats compared with controls and repleted rats. Liver Scd1 mRNA expression and activity indices were positively correlated with plasma triglyceride levels. These preclinical findings demonstrate that n−3 fatty acid status is an important determinant of liver Scd1 mRNA expression and activity, and suggest that down-regulation of Scd1 is a mechanism by which n−3 fatty acids repress constitutive triglyceride biosynthesis.

Subcutaneous and intramuscular adipose tissue stearoyl-coenzyme A desaturase gene expression and fatty acid composition in calf- and yearling-fed Angus steers1

We proposed that stearoyl-CoA desaturase (SCD) activity dictates fatty acid composition of adipose tissue and muscle in beef cattle, regardless of ruminal or hepatic fatty acid hydrogenation or desaturation. Twelve Angus steers were assigned to a calf-fed (CF) group and slaughtered at weaning (8 mo of age; n=4), 12 mo of age (n=4), or 16 mo of age (n=4). Twelve steers were assigned to a yearling-fed (YF) group and slaughtered at 12 mo of age (n=4), 16 mo of age (n=4), and 17.5 mo of age (n=4; 525 kg, market weight). Data were analyzed based on time on the corn-based finishing diet, with terminal age as a covariate, and orthogonal polynomial contrasts were tested on the main effects of treatment group and time on the finishing diet. Fatty acids from duodenal digesta, plasma, liver, LM, and subcutaneous and intramuscular adipose tissue were measured, and SCD gene expression was measured in intramuscular and subcutaneous adipose tissues. In duodenal digesta, palmitic and linoleic acids increased by 100% over the sampling period, α-linolenic acid decreased over the sampling period, and trans-vaccenic acid was greater in YF than in CF steers (all P < 0.01). The proportion of α-linolenic acid decreased over time in all tissues, including liver. The SCD index (ratio of SCD fatty acid products to SCD fatty acid substrates) increased over time in LM and in intramuscular and subcutaneous adipose tissues. The SCD:glyceraldehyde 3-phosphate dehydrogenase mRNA ratio was virtually undetectable at the initial sampling periods in subcutaneous adipose tissue of YF and CF steers, and it increased over time (P < 0.01). The SCD index and SCD:glyceraldehyde 3-phosphate dehydrogenase ratio were greater in intramuscular adipose tissue of CF steers than in that of YF steers. The SCD index did not change over time in liver and decreased over time in duodenal digesta. We conclude that, unlike essential fatty acids, the SFA and MUFA composition of adipose tissue is regulated by adipose tissue fatty acid desaturation, with little contribution from hepatic or duodenal fatty acids.

Impact of feeding various amounts of wet and dry distillers grains to yearling steers on palatability, fatty acid profile, and retail case life of longissimus muscle1

Due to increased production of ethanol, abundance of distillers grains (DG) is increasing. Steers (n = 176) were assigned to 1 of 5 treatment groups: steam-flaked corn (SFC), 10% dry DG (DDG), 10% wet DG (WDG), 20% WDG, or 30% WDG. The objectives were to determine the effects of feeding greater amounts of WDG, or DDG on meat quality. Steaks, 2.54 cm, were cut from strip loins and identified for simulated retail display, Warner-Bratzler shear force analysis, palatability, and fatty acid composition. Steaks from cattle fed 10% WDG and 30% WDG had smaller (P < 0.05) Warner-Bratzler shear force values than steaks from cattle fed 20% WDG. Trained sensory panelists found no differences (P > 0.05) in overall tenderness and off-flavors. No differences were found in total SFA and MUFA composition among treatments; however, 20% and 30% WDG had a greater proportion of PUFA and n-6 fatty acids than 10% WDG. No differences were found during simulated retail display between various amounts of WDG. Further research needs to be conducted to evaluate methods that aid in increasing shelf life of steaks from cattle fed greater rates of WDG.

사료 내 목초액의 첨가가 토종닭의 생산성, 혈액성상, 암모니아 가스 발생량 및 가슴육의 지방산 조성에 미치는 영향

본 시험은 목초액이 토종닭 한협 3호의 생산성, 유해 가스 발생량, 혈액 성상 그리고 가슴육의 지방산 함량에 미치는 영향을 평가하기 위하여 토종닭 사료에 수준별로 첨가하여 70일 동안 급여하였다. 목초액은 0, 0.1, 0.2% 수준으로 첨가 급여하였고, 처리구당 5반복, 반복당 16수씩 총 240수를 시험에 이용하였다. 시험 결과, 목초액은 생산성에 있어서 큰 영향을 미치지 못하였으나, 암모니아 가스 발생량은 대조구에 비하여 유의하게 감소시켰다(p<0.05). 혈중 total cholesterol과 HDL-cholesterol 농도에 있어서는 목초액 처리구가 대조구에 비하여 유의하게 증가한 반면 triglyceride의 농도는 감소하였다(p<0.05). 가슴육의 포화지방산인 myristic acid와 stearic acid는 목초액을 급여함에 따라 대조구에 비하여 유의적으로 감소하였으나, 불포화지방산인 oleic acid와 linolenic acid는 유의적으로 증가하였다(P<0.05). 따라서 본 연구 결과, 목초액은 유해 가스 저감 효과가 있으며, 토종닭의 혈중 지질 수준을 개선시키고, 가슴육의 포화지방산 함량을 감소시키고 단쇄 불포화지방산의 함량은 증가시키는 것으로 판단된다. The current study was conducted to estimate the effect of dietary pyroligneous acid (PA) on performance, noxious gas emission in excreta, blood parameter and fatty acid composition of breast meat in Korean native chicken. A total of 240 one-day-old chicks were allocated to three treatments (PA; 0, 0.1, 0.2%) with five replicate of 16 each per treatment for 10 weeks. Although there was no effect on the performance, ammonia gas concentration was significantly decreased in the PA treatments compared to the control (p<0.05). Birds fed PA had higher serum total protein and high density lipoprotein-cholesterol (HDL-cholesterol) concentration but lower triglyceride content in the PA 0.2% treatment than control (p<0.05). In fatty acids composition of breast meat, myristic and stearic acid were significantly decreased, whereas oleic and linolenic acid were significantly increased in the group fed PA compared to those of the control group (p<0.05). The result of the current study indicates that dietary PA may reduce the noxious gas emission and improve lipid levels as well as increase of monounsaturated fatty acids composition of breast meat in Korean native chickens.