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1.
Effects of feeding conjugated linoleic acid (CLA) to hens on progeny chick development and composition at hatch (NHC) and three weeks of age (TWC) were assessed. CLA (0 or 0.5%, composed of mixed isomers of cis-9,trans-11 or trans-10,cis-12-CLA) was fed to hens with either safflower (SO) or olive oil (OO) (3 or 3.5%) to assure successful hatch for 2 weeks prior to collection for incubation. Maternal CLA feeding had no effect on hatchability, but improved egg fertility (p < 0.05). Maternal feeding of CLA with SO increased 21 day-old progeny growth, while CLA with OO decreased growth (oil*CLA, p < 0.05). In 25 day-old chicks (TWC), but not NHC, maternal CLA decreased the proportion of total body water (p < 0.05) and increased body ash (p < 0.05). While monounsaturated fatty acids were decreased and saturated fatty acids increased in eggs and NHC from hens fed CLA, no differences in fatty acid composition were observed in chicks at 25 days of age from hens fed CLA. Maternal CLA feeding resulted in the presence of c9,t11 and t10,c12-CLA in NHC, but only c9,t11 in the TWC. In conclusion, hens fed CLA led to improved fertility and altered body composition at 3 weeks of age.  相似文献   

2.
High stearic, low α-linolenic acid soybean oil (HSLL) has been developed via traditional breeding to serve as a substitute for partially hydrogenated soybean oils used in food manufacturing. The purpose of this study was to estimate the impact on fatty acid intake in the United States if HSLL were substituted for partially hydrogenated soybean oils used in several food categories, including baked goods, shortenings, fried foods, and margarines. Using National Health and Nutrition Examination Survey (NHANES) data (1999–2002), baseline intakes of five fatty acids and trans fatty acids (TFA) were determined at the mean and 90th percentile of fat consumption. Then intakes of these fatty acids were determined after HSLL was substituted for 100% of the partially hydrogenated soybean oils used in these four food categories. The results show that baseline intake of stearic acid is 3.0% energy at the mean and 3.3% energy at the 90th percentile. Use of HSLL could increase stearic acid intake to about 4–5% energy. Mean intakes of TFA could decrease from 2.5 to 0.9% energy, and intake of palmitic acid would remain unchanged. Use of HSLL as a substitute for partially hydrogenated soybean oils would result in changes in the fatty acid composition of the US diet consistent with current dietary recommendations.  相似文献   

3.
4.
The photosulfochlorination process has been used in earlier works to produce n-alkane sulfonates. In this work, this process was applied for the first time on lauric and myristic fatty acids, leading to methyl ester sulfonates (MESs). The operating conditions were optimized and the isolation method described. Apart from the known advantages of this reaction, namely the use of sulfuryl chloride, the visible light and short reaction time, this process led to a clear mono-sulfonate products and thus allowed avoiding the bleaching step. The chemical composition of these surfactants was determined and their structures characterized by Fourier transform infrared spectroscopy, liquid chromatography-electrospray ionization tandem mass spectrometry and proton nuclear magnetic resonance. The physicochemical properties of these surfactants such as surface tension, critical micelle concentration, maximum surface excess and minimum area per molecule of surfactant at the air/water interface were determined. The Krafft point was determined experimentally and compared to the MES literature data. The experimental and calculated hydrophilic–lipophilic balance values obtained compared well. The foaming power using Bartsch’s method was presented and the results obtained compared to those of similar structures and those of sodium dodecyl sulfate.  相似文献   

5.
This study presented a refining process and reported on fatty acid composition and the physicochemical properties of the oil from black soldier fly larvae (BSFL). Crude larvae oil was purified through four steps consisting of degumming, neutralization, bleaching, and deodorization. Optimum degumming conditions that give the highest phospholipid weight and oil consisted of water concentration of 7% (v/v), followed by addition of H2SO4 at a concentration of 0.5% (v/v). Optimum conditions for saponification that maximize saponification value and free fatty acid (FFA) value were 0.4 mg NaOH/100 g oil, 1 hour, and 80 °C of NaOH quantity, reaction time, and temperature, respectively. The oil was then dehydrated using 10 mg Na2SO4/g oil. The bleaching process that gives maximum oil yield consisted of activated carbon at concentration of 5% (w/w), followed by centrifugation at a speed of 5000 rpm (radius = 86 mm) for 30 min. The contents of lauric acid, linoleic acid, and linolenic acid in purified oil were 28.8%, 11.1%, and 0.4%, respectively. Physicochemical properties of the refined oil included viscosity of 96 ± 0.14 cP (measured at 20 °C), FFA value of 0.45 ± 0.017%, acid value of 0.9 ± 0.043 mg KOH g−1, saponification value of 215.78 mg KOH g−1, iodine value of 53.7 gI2/100 g, and peroxide index of 133 mEq kg−1.  相似文献   

6.
7.
The uptake of specific fatty acids in humans is dependent on their position on the glycerol backbone. There is a great interest in methods that can access this information fast and accurately. By way of high-resolution NMR, we have analyzed TAG extracted from pig and beef tissues and obtained quantitative data for the composition and regioisomeric distribution of all major unsaturated fatty acids usually found in these source materials, using a combination of manual integration and deconvolution of 13C NMR spectra. In addition, we have developed a method for determining composition and regioisomeric distribution of the two main saturated fatty acids found in pork (16:0, 18:0). The results are discussed in relation to species-specific genetic characteristics of fatty acid and TAG biosynthesis. The developed method could support decisions related to breeding for desired fatty acid profiles, and stimulate further methodology developments using high field NMR.  相似文献   

8.
Production of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in plant seed oils has been pursued to improve availability of these omega‐3 fatty acids that provide important human health benefits. Canola (Brassica napus), through the introduction of 10 enzymes, can convert oleic acid (OLA) into EPA and ultimately DHA through a pathway consisting of two elongation and five desaturation steps. Herein we present an assessment of the substrate specificity of the seven desaturases and three elongases that were introduced into canola by expressing individual proteins in yeast. In vivo feeding experiments were conducted with 14 potential fatty acid intermediates in an OLA to DHA pathway to determine the fatty acid substrate profiles for each enzyme. Membrane fractions were prepared from yeast expression strains and shown to contain active enzymes. The elongases, as expected, extended acyl‐CoA substrates in the presence of malonyl‐CoA. To distinguish between enzymes that desaturate CoA‐ and phosphatidylcholine‐linked fatty acid substrates, we developed a novel in vitro method. We show that a delta‐12 desaturase from Phytophthora sojae, an omega‐3 desaturase from Phytophthora infestans and a delta‐4 desaturase from Thraustochytrium sp., all prefer phosphatidylcholine‐linked acyl substrates with comparatively low use of acyl‐CoA substrates. To further validate our method, a delta‐9 desaturase from Saccharomyces cerevisiae was confirmed to use acyl‐CoA as substrate, but could not use phosphatidylcholine‐linked substrates. The results and the assay methods presented herein will be useful in efforts to improve modeling of fatty acid metabolism and production of EPA and DHA in plants.  相似文献   

9.
Hedrick DB  Peacock AD  Long P  White DC 《Lipids》2008,43(9):843-851
A previously unreported series of di- and tri-methylated fatty acids, as well as saturated and monounsaturated diacids were identified in polar lipids isolated from environmental subsurface sediment samples. Mechanisms are proposed for their formation, but their origin and role in cell membranes remains unknown.  相似文献   

10.
Intrauterine growth restriction (IUGR) with rapid catch‐up growth leads to adult obesity and insulin resistance. We have previously shown that IUGR male rats demonstrated increased de novo fatty acid synthesis in the subcutaneous (SC) fat, but not the visceral fat, during the nursing period prior to the onset of obesity. Young IUGR females do not exhibit the same increase. We further hypothesized that in male IUGR offspring, de novo synthesis is a programmed intrinsic effect that persists to adulthood and does not suppress in response to a high fat diet. We measured fatty acid de novo synthesis in IUGR adult males (6 months) using deuterium‐enriched drinking water as a stable isotope tracer, then further studied the response after consumption of an isocaloric high fat diet. Baseline de novo synthesis in adult females was also studied at age 9 months. Males demonstrated increased baseline de novo synthesis in both SC fat and visceral fat. Correspondingly, SC and visceral fat protein expression of lipogenic enzymes acetyl‐coA carboxylase‐α (ACCα) and fatty acid synthase were upregulated. After the isocaloric high fat diet, de novo synthesis was suppressed such that no differences remained between the two groups, although, IUGR SC fat demonstrated persistently increased lipogenic protein expression. In contrast, de novo synthesis among adult females is not impacted in IUGR. In conclusion, enhancement of male IUGR SC fat de novo synthesis appears to be an early consequence of metabolic programming, whereas enhancement in visceral fat appears to be a later consequence.  相似文献   

11.
This study focuses on new interpretations of the published literature by statistically evaluating the potential of microbial lipids from activated sludge (AS) as alternatives to high-value oils and fats. There are two data analysis stages involved in this study after compilation and organization of fatty acid profiles from the literature databases: (1) comparison of fatty acid profiles of the cultivated AS lipids with that of oils and fats found in the literature databases, and (2) hierarchical cluster analysis of the fatty acids of the combined dataset of literature oils and fats, and the AS lipids. Results show that fatty acid profiles of lipids from cultivated AS were similar to the fatty acid profiles of some oils and fats of plant, animal, single-microbial cultures, and algal origins; hence, lipids from AS could be potential alternatives to specialty oils and fats. The cultivation conditions of AS during lipid content enhancement may influence lipid application.  相似文献   

12.
Chickens can hepatically synthesize eicosapentaenoic acid (20:5 n‐3) and docosahexaenoic acid (22:6 n‐3) from α‐linolenic acid (ALA; 18:3 n‐3); however, the process is inefficient and competitively inhibited by dietary linoleic acid (LNA; 18:2 n‐6). In the present study, the influence of dietary high‐oleic acid (OLA; 18:1 n‐9) soybean oil (HOSO) on egg and tissue deposition of ALA and n‐3 polyunsaturated fatty acids (PUFA) synthesized from dietary ALA was investigated in laying hens fed a reduced‐LNA base diet supplemented with high‐ALA flaxseed oil (FLAX). We hypothesized that reducing the dietary level of LNA would promote greater hepatic conversion of ALA to very long‐chain (VLC; >20C) n‐3 PUFA, while supplemental dietary HOSO would simultaneously further enrich eggs with OLA without influencing egg n‐3 PUFA contents. Nine 51‐week‐old hens each were fed 0, 10, 20, or 40 g HOSO/kg diet for 12 weeks. Within each group, supplemental dietary FLAX was increased every 3 weeks from 0 to 10 to 20 to 40 g/kg diet. Compared to controls, dietary FLAX maximally enriched the total n‐3 and VLC n‐3 PUFA contents in egg yolk by 9.4‐fold and 2.2‐fold, respectively, while feeding hens 40 g HOSO/kg diet maximally attenuated the yolk deposition of ALA, VLC n‐3 PUFA, and total n‐3 PUFA by 37, 15, and 32%, respectively. These results suggest that dietary OLA is not neutral with regard to the overall process by which dietary ALA is absorbed, metabolized, and deposited into egg yolk, either intact or in the form of longer‐chain/more unsaturated n‐3 PUFA derivatives.  相似文献   

13.
The aim of this study was to examine the influence of dietary fat on lipid composition, as well as on the steroidogenic function of interstitial cells isolated from Wistar rats that had been fed semi-synthetic diets containing four different commercial oils (S soybean, O olive, C coconut, and G grape seed). Steroidogenic enzyme activities, lipid composition, and androgen production were measured in testicular interstitial cells. Lipid analysis included measurement of the contents of major lipid subclasses (neutral lipids, polar lipids, free and esterified cholesterol), as well as principal polar and neutral lipid fatty acyl compositions. Significant differences in lipid composition were observed among the groups, most of them reflecting the specific fatty acyl composition of the diet tested. Testosterone concentration was higher in O and C groups compared with S or G. In agreement with this observation, the activity of both key enzymes involved in testosterone biosynthesis (3-β-HSD and 17-β-HSD) was higher in O and C groups with significant differences between them (O > C). A significant negative correlation was found between cellular testosterone production and cellular cholesterol ester content. Additionally, testosterone concentration directly correlated with cholesterol levels. We conclude that dietary oils qualitatively and quantitatively modified the lipid composition of interstitial cells, producing either a direct or indirect regulatory effect on testicular steroidogenic function.  相似文献   

14.
To better understand how docosahexaenoic acid (DHA) improves the effects of doxorubicin (DOX), we examined DHA ± DOX on changes in whole cell and lipid raft phospholipids (PL) of MDA-MB-231 and MCF-7 breast cancer cells. We sought to confirm whether the relative changes in PL DHA content of MDA-MB-231 cells could be extended to PL from MDA-MB-231 tumors grown in mice fed a DHA supplemented diet ±DOX. Treatment with DHA did not change PL composition yet DOX increased the proportion of phosphatidylserine in MCF-7 cell lipid rafts by two-fold (p < 0.001). Regardless of DOX, the relative percent incorporation of DHA was higher in MDA-MB-231 cells compared to MCF-7 cells in phosphatidylserine, phosphatidylethanolamine, and phosphatidylcholine (whole cell and lipid rafts); and higher in phosphatidylethanolamine vs. phosphatidylcholine (4.4-fold in MCF-7 and 6-fold in MDA-MB-231 cells respectively). DHA treatment increased eicosapentaenoic acid and docosapentaenoic acid in MDA-MB-231 cells but not MCF-7 cells. Increased DHA content in MDA-MB-231 cells, MCF-7 cells, and MDA-MB-231 tumors in all PL moieties (except sphingomyelin) corresponded with reduced arachidonic acid (p < 0.05). Feeding mice 2.8% (w/w of fat) DHA ± DOX increased tumor necrotic regions (p < 0.05). This study established differential incorporation of DHA into whole cell and lipid rafts between human breast cancer cell lines. However, within each cell line, this incorporation was not altered by DOX confirming that DOX does not change membrane lipid composition. Furthermore, our findings indicate that membrane changes observed in vitro are translatable to in vivo changes and that DHA + DOX could contribute to the anticancer effects through increased necrosis.  相似文献   

15.
J. Seemann  Y. Sawall  H. Auel  C. Richter 《Lipids》2013,48(3):275-286
Following up on previous investigations on the stress resistance of corals, this study assessed the trophic plasticity of the coral Stylophora subseriata in the Spermonde Archipelago (Indonesia) along an eutrophication gradient. Trophic plasticity was assessed in terms of lipid content and fatty acid composition in the holobiont relative to its plankton (50–300 μm) food as well as the zooxanthellae density, lipid, FA and chlorophyll a content. A cross-transplantation experiment was carried out for 1.5 months in order to assess the trophic potential of corals. Corals, which live in the eutrophied nearshore area showed higher zooxanthellae and chlorophyll a values and higher amounts of the dinoflagellate biomarker FA 18:4n-3. Their lipid contents were maintained at similar to levels from specimens further away from the anthropogenic impact source going up to 14.9 ± 0.9 %. A similarity percentage analysis of the groups holobiont, zooxanthellae and plankton >55 μm found that differences between the FA composition of the holobiont and zooxanthellae symbionts were more distinct in the site closer to the shore, thus heterotrophic feeding became more important. Transplanted corals attained very similar zooxanthellae, chlorophyll a and lipid values at all sites as the specimens originating from those sites, which indicates a high potential for trophic plasticity in the case of a change in food sources, which makes this species competitive and resistant to eutrophication.  相似文献   

16.
The lipid and fatty acid compositions in the various organs (muscle, liver, other viscera) and stomach contents of three common herbivorous fish species in Japan, Siganus fuscescens, Calotomus japonicus and Kyphosus bigibbus, were examined to explore the stable 20:4n-6 (arachidonic acid, ARA) sources. Triacylglycerol (TAG), phosphatidylethanolamine (PtdEtn), and phosphatidylcholine (PtdCho) were the dominant lipid classes, while the major FA contents were 16:0, 18:1n-9, 16:1n-7, 14:0, 18:0, 18:1n-7, and some PUFA, including ARA, 20:5n-3 (eicosapentaenoic acid, EPA), 22:5n-3 (docosapentaenoic acid, DPA), and 22:6n-3 (docosahexaenoic acid, DHA). The amounts of these fatty acids were varied among species and their lipid classes. Phospholipids contained higher levels of PUFA than TAG. However, ARA in both phospholipids and TAG was markedly present in the muscle and viscera of all specimens, particularly in C. japonicus and K. bigibbus. Moreover, their ARA levels were higher than the levels of DHA and EPA. The observed high ARA level is unusual in marine fish and might be characteristic of herbivorous fish. Furthermore, ARA was the dominant PUFA in the stomach contents of the three species, suggesting that the high ARA level originated from their food sources. The above indicates that these three herbivorous fishes are ARA-rich marine foods and have potential utilization as stable ARA resources.  相似文献   

17.
In the present study, the lipid amount and fatty acid profile of different Sparidae species, including gilthead seabream, juvenile gilthead seabream, annular seabream, white seabream, common two-banded seabream were evaluated. Fish were seasonally collected from Köyceğiz Lagoon (Muğla, South Western Turkey) from June 2018 to June 2019 and after collection, the sex of each specimen was recorded. According to the results of the study, the highest lipid amount was found in female annular seabream individuals as 8.09 ± 0.78% in November and the lowest lipid amount was found in male juvenile gilthead seabream as 0.98 ± 0.12% in March. Palmitic acid and oleic acid were determined as the most abundant SFA and MUFA for all species, respectively. The highest value of DHA, which was the predominant PUFA was assessed as 15.33 ± 0.26% in female white seabream in November whereas the lowest value (3.83 ± 0.36%) was found in gilthead seabream in December. The n-6/n-3 ratio was determined between 0.27 ± 0.00 (for male common two-banded seabream in July)-1.20 ± 0.03 (for male gilthead seabream in December) and it followed within the range of healthy values for all species. As a conclusion, it was found that values of lipid and fatty acid profiles among the examined Sparidae species vary among the season of collection. The results of the study gave the seasonal nutritional values of four economically-important Sparidae species that being rich in healthy polyunsaturated fatty acids such as DHA, have beneficial in human nutrition.  相似文献   

18.
Milk fat is known to contain one of the highest number of fatty acids of all edible oils. Some of these fatty acids are known to be valuable (e.g. conjugated linoleic acids, furan fatty acid) and other as undesirable (e.g. saturated and some trans-fatty acids) food ingredients. However, a comprehensive picture on the presence of many trace fatty acids has not been achieved. For this reason we have developed an analysis scheme based on the conversion of the fatty acids into methyl esters. The fatty acid methyl esters were then fractionated by urea complexation. Both the filtrate of the urea complexation (~4 % of the sample weight) and the original sample were fractionated by high-speed counter-current chromatography (HSCCC). The resulting fractions were analyzed by GC/MS analysis. With this method 430 fatty acids were detected in one single butter sample. More than 230 fatty acids had two or more double bonds. In addition to the widely known spectrum of fatty acids we also detected a range of cyclohexyl fatty acids (five homologues) and methyl-branched fatty acids (including short chain and even-numbered anteiso-fatty acids), conjugated tetradecadienoic acids along with the novel ω-oxo-fatty acids (seven homologues). The reported relative retention time on the polar column may serve as a data base for the screening of other samples for this profusion of fatty acids.  相似文献   

19.
Contradictory results have been found in the response of dairy goats to the supplementation of fish oil in their diet to improve the n-3 polyunsaturated fatty acids (PUFA) in milk. The responses to the inclusion of fish oil in the diet of ruminants either induced milk fat depression, increased milk fat content, and/or negatively impacted milk yield. The objective of this study was to determine whether including a low dose of encapsulated fish oil in the diet of goats can modify yield, milk composition, and the fatty acid (FA) profile of milk. Ten Alpine goats were divided into two homogeneous subgroups and assigned to either the control or experimental diet. The control animals received the basal diet without supplementation of fish oil, whereas the experimental group was given the same basal diet supplemented with encapsulated fish oil (1.14 g /kg of concentrate) for 56 days. Milk samples were analyzed for chemical composition and FA profile. The inclusion of encapsulated fish oil in the goat diet did not affect the yield and composition of goat milk. The effect of diet was not significant on the FA profile of goat milk, except that 20:0 was lower (P < 0.05) in the milk of goats that received fish oil. The low dose of encapsulated fish oil supplement used in this study did not impact (P > 0.05) the PUFA content of goat milk or milk composition and yield; however, the atherogenicity index (AI), which is beneficial to heart health, was lower (P < 0.05) in the milk of goats that received fish oil as a supplement in their diet compared to the control.  相似文献   

20.
The fat contents of 12 brands of biscuits were extracted and evaluated for free fatty acids (FFA) and their fatty acid composition (FAC). The oil content and FFA varied from 13.7 to 27.6% and 0.2 to 1.0%, respectively. The FAC was analyzed by gas chromatography–mass spectroscopy with particular emphasis on trans fatty acids (TFA). Total saturated, unsaturated, cis-monounsaturated and polyunsaturated fatty acids were determined in the range of 37.9–46.9, 53.0–62.0, 12.3–43.7 and 0.1–9.2%, respectively. The high amount of TFA was observed in all biscuit samples and varied from 9.3 to 34.9%. The quantity and quality of the lipid fraction of the biscuits indicated that the all analyzed biscuits are a rich source of fat, saturated fatty acids and trans fatty acids, consequently not suitable for the health of consumers. The high content of trans fatty acids and palmitic acid also indicated that blends of RBD palm oil and partially hydrogenated oil had been used in the biscuit manufacturing.  相似文献   

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