Lipid Classes,Fatty Acids and Triglycerides in Papaya Seed Oil

Seed oil from papaya, cultivated in Vietnam, which accounted for 28% of the whole dried seeds and 54% of the endosperm was characterized by composition of lipid classes, fatty acids and triglycerides. Eleven triglyceride groups differing in unsaturation are determined by argentation thin-layer chromatography and densitometry. The fatty acid and triglyceride compositions of papaya seed oil are close to those of olive oil and characterize it as a good natural raw material.     

In vitro and in vivo Digestibility of Blended and Corresponding Interesterified Fats in Rats

The process of interesterification of fat blends namely vanaspati-ground-nut oil (40:60) (vanaspati-GNO), sal fat and groundnut oil (30:70) (sal-GNO), sheep tallow and groundnut oil (30:70) (ST-GNO), and cottonseed oil (CSO) was found to bring about limited but consistent increase in in vitro digestibility (compared to starting stocks) during first four hours studied. Apparent digestibility of blends of sal-GNO and vanaspati-GNO in rats was not effected by the process of interesterification while interesterified products had significantly higher in vivo true digestibility compared to starting stocks.     

Feeding Effect of Some Poultry Byproducts on Chicken's Serum Fatty Acids

The most important fat chemical constants for mesentric fat used as a part of the diet given to chickens were determined. This fat was characterized by fairly low acid and iodine values. Analysis of its fatty acids indicated that 10:0, 14:0, 17:0, 18:1 and 20:1 present in amounts greater than 10%, 17:0 and 20:1 being the most abundant odd and even carbon acids, respectively. A wide variety of fatty acids (10:0–20:1) were found in chicken's serum including even-carbon saturated and unsaturated acids and saturated odd-carbon acids. The concentration of individual fatty acids and their degree of unsaturation in chicken's serum varied according to different feeding regimes.     

Fatty Acids and Lipid Paradox-Neuroprotective Biomarkers in Ischemic Stroke

Stroke is the primary cause of death and disability worldwide, with ischemic stroke up to 80% of the total cases. Lipid profile was established as a major risk factor for stroke, but recent studies show a paradoxical relationship between serum values and the outcome of stroke patients. Our study aims to analyze the impact of the classic extended lipid profile, including fatty acids as potential neuroprotective biomarkers for the outcome of ischemic stroke patients. We included 298 patients and collected clinical, paraclinical, and outcome parameters. We used a method consisting of high-performance liquid chromatography coupled with mass spectrometry to quantify serum fatty acids. We observed a negative correlation between National Institutes of Health Stroke Scale (NIHSS) at admission and total cholesterol (p = 0.040; r = −0.120), respectively triglycerides (p = 0.041; r = −0.122). The eicosapentaenoic to arachidonic acid ratio has a negative correlation, while the docosahexaenoic to eicosapentaenoic acid ratio positively correlates with all the prognostic parameters, showing a potential neuroprotective role for eicosapentaenoic acid in preventing severe ischemic stroke. The impact of the lipid profile paradox and the dependency relationship with the fatty acids represent a significant predictive factor for the functional and disability prognostic of ischemic stroke patients.     

Dimer and Trimer Fatty Acids in Feed Fats Characterized by HPLC-GPC and MS

Commercial feed fats, animal fat distillation residue, bleached earth oil and abused frying fat were fractionated into monomeric and dimeric triglycerides by means of gel permeation chromatography. Upon hydrolysis and methylation the mixtures were analysed by electron impact mass spectrometry using the integrated ion current technique. All samples contained a fraction of dimeric fatty acid methyl ester with molecular ions at m/z 584 , 586, 588 and 590, probably representing a great variety of both cyclic and linear structures. The individual dimers are not separated by this technique but the mass spectra of the multicomponent dimer fractions of all feed fats investigated showed remarkable resemblance. This may indicate that the dimeric fatty acids generated through intermolecular dimerization between two triglycerides are rather similar to those formed through intramolecular dimerization within the triglycerides. In two cases only trimeric fatty acids methyl esters were observed. The actual concentration of dimeric fatty acids was determined by HPLC-GPC to 3.7-13.7%.     

Stability of Emulsions Containing Interesterified Fats Based on Mutton Tallow and Walnut Oil

In this work, modified fats were produced by enzymatic interesterification of mutton tallow with walnut oil. As a result of forcing the fat hydrolysis process by addition of water to the enzymatic preparation (11.5, 13.0, 14.5, 16.0 wt %), additional levels of polar fractions (MAGs, DAGs, and FFAs) were observed. The aim of this work was to evaluate the stability of emulsions of modified fats containing natural emulsifiers resulting from enzymatic interesterification of mutton tallow with walnut oil. The physical‐chemical parameters of obtained fats were determined in this study. Using several methods, the stability of the formed emulsions was also evaluated. The results showed that the fats resulting from interesterification in the presence of Lipozyme RM IM (immobilized lipase from Rhizomucor miehei, Novozymes Bagsvaerd, Denmark) with 13.0, 14.5, and 16.0 wt % of water in the enzymatic preparation could form stable emulsion systems. On the other hand, the emulsion of the interesterification system where the amount of water in the enzymatic preparation was 11.5 % showed very low stability. The number of natural emulsifiers (MAGs and DAGs) that arose after interesterification was insufficient to stabilize the emulsion system. The work has shown the possibility of using interesterified fats as the fat phase. Emulsions formed on the basis of interesterified fats without any additional emulsifiers such as sunflower lecithin had properties comparable to emulsions containing mixed non‐interesterified fat containing additional emulsifier. The natural emulsifiers formed as part of enzymatic interesterification allow formation of stable emulsion systems.     

trans Fatty Acids in Colostrum,Mature Milk and Diet of Lactating Adolescents

The purpose of this study was to investigate the trans fatty acids (TFA) content and distribution in colostrum, mature milk, and diet of adolescent mothers, after TFA declaration in food labels became mandatory in Brazil. Participants were healthy adolescents (n 54, 15–19 years, 1–90 days postpartum) practicing exclusive breastfeeding. Milk samples were collected 3 days after delivery (colostrum) and in the third month postpartum (mature milk) by hand expression. The fatty acid composition of the milk samples was determined by gas chromatography. TFA intake corresponded to 1.23 % of total energy value. Total 18:2 TFA accounted for less than 0.5 % of the energy intake. The amount of total 18:1 TFA (mean ± SEM) was 1.9 % ± 0.14 in colostrum and 1.5 % ± 0.2 in mature milk. The total content of n‐3 PUFA was inversely correlated with the total content of 18:1 TFA in colostrum. Both in colostrum and in mature milk, vaccenic acid (11t‐18:1) was found to be the most abundant 18:1 trans isomer, followed by elaidic acid (9t‐18:1), whereas rumenic acid (9c,11t‐18:2 CLA) was the predominant 18:2 trans isomer. In conclusion, the levels of TFA of industrial sources found in the mother's diet and breast milk (colostrum and mature milk) showed a decrease in relation to those observed in studies conducted prior to the TFA labeling resolution in Brazil. However, the current low intake levels of n‐3 LCPUFA and DHA content in the milk of lactating adolescents may be insufficient for supporting adequate neurological development of the infants.     

Raman Study on Lipid Droplets in Hepatic Cells Co-Cultured with Fatty Acids

The purpose of the present study was to investigate molecular compositions of lipid droplets changing in live hepatic cells stimulated with major fatty acids in the human body, i.e., palmitic, stearic, oleic, and linoleic acids. HepG2 cells were used as the model hepatic cells. Morphological changes of lipid droplets were observed by optical microscopy and transmission electron microscopy (TEM) during co-cultivation with fatty acids up to 5 days. The compositional changes in the fatty chains included in the lipid droplets were analyzed via Raman spectroscopy and chemometrics. The growth curves of the cells indicated that palmitic, stearic, and linoleic acids induced cell death in HepG2 cells, but oleic acid did not. Microscopic observations suggested that the rates of fat accumulation were high for oleic and linoleic acids, but low for palmitic and stearic acids. Raman analysis indicated that linoleic fatty chains taken into the cells are modified into oleic fatty chains. These results suggest that the signaling pathway of cell death is independent of fat stimulations. Moreover, these results suggest that hepatic cells have a high affinity for linoleic acid, but linoleic acid induces cell death in these cells. This may be one of the causes of inflammation in nonalcoholic fatty liver disease (NAFLD).     

Evaluation of Isolated Impact of Trans Fatty Acids on Short Dough Product

In this study, the effects of trans fatty acids (TFAs) on rheological properties of dough (elastic moduli (G’), loss moduli (G”), complex modulus (G*)) and textural properties of dough and cookie (hardness) were studied. Two different groups of fat samples having different TFA composition but similar solid fat content (SFC) were prepared. Samples of the first group (group 1) had TFA between 0.0 and 56.23 %, while the samples of the second group (group 2) contained trans isomers ranging from 0.0 to 44.40 %. Texture measurements of different doughs and cookies prepared with different fat samples were performed. Texture measurements indicated that hardness values of doughs increased from 3950 ± 420 to 5498 ± 506 g in group 1 and 4700 ± 501 to 6787 ± 369 g in group 2 with increased amounts of TFAs. A particularly high, almost three‐fold increase in complex modulus values was observed in the dough samples containing the highest TFA levels compared with samples containing 0.0 % TFA. Although not significantly different, mean hardness and relative sound intensity values of cookies displayed an initial decreasing trend and then both parameters had maximum values when the TFA content was at maximum in both groups.     

Fatty Acid and Lipid Profiles with Emphasis on n-3 Fatty Acids and Phospholipids from Ciona intestinalis

In order to establish Ciona intestinalis as a new bioresource for n‐3 fatty acids‐rich marine lipids, the animal was fractionated into tunic and inner body tissues prior to lipid extraction. The lipids obtained were further classified into neutral lipids (NL), glycolipids (GL) and phospholipids (PL) followed by qualitative and quantitative analysis using GC‐FID, GC–MS, ¹H NMR, 2D NMR, MALDI‐TOF‐MS and LC–ESI–MS methods. It was found that the tunic and inner body tissues contained 3.42–4.08 % and 15.9–23.4 % of lipids respectively. PL was the dominant lipid class (42–60 %) irrespective of the anatomic fractions. From all lipid fractions and classes, the major fatty acids were 16:0, 18:1n‐9, C20:1n‐9, C20:5n‐3 (EPA) and C22:6n‐3 (DHA). The highest amounts of long chain n‐3 fatty acids, mainly EPA and DHA, were located in PL from both body fractions. Cholestanol and cholesterol were the dominant sterols together with noticeable amounts of stellasterol, 22 (Z)‐dehydrocholesterol and lathosterol. Several other identified and two yet unidentified sterols were observed for the first time from C. intestinalis. Different molecular species of phosphatidylcholine (34 species), sphingomyelin (2 species), phosphatidylethanolamine (2 species), phosphatidylserine (10 species), phosphatidylglycerol (9 species), ceramide (38 species) and lysophospholipid (5 species) were identified, representing the most systematic PL profiling knowledge so far for the animal. It could be concluded that C. intestinalis lipids should be a good alternative for fish oil with high contents of n‐3 fatty acids. The lipids would be more bioavailable due to the presence of the fatty acids being mainly in the form of PL.     

Inhibitory Effect of Amino Acids and Dipeptides on the Sensitized Photooxidation of Fats

The protective effect of amino acids and dipeptides on the singlet molecular oxygen photo-oxidation of soybean oil and thier FAME was investigated, in homogeneous media and in aqueous emulsions. Soybean oil was chosen as an example of fat due to its particular stability problem. In the presence of 10–100 ppm of the amino acids, photo-oxidation of the fats in relatively concentrated solutions, was considerably retarded when exposed to visible light, with an added sensitizer. The study indicates that amino acids and peptides, could acd as protective agents against fats photo-oxidation, specially in foods containing oxidizable non saturated fatty acids, constituted in many cases by emulsions, where fats can simultaneously be disolved with proteineaceous compounds.     

Alteration of Endogenous Fatty Acids Profile and Lipid Metabolism in Rats Caused by a High-Colleseed Oil and a High-Sunflower Oil Diet

Dietary fat has an important influence on mammalian lipid homeostasis. However, the relationship between dietary fat types and endogenous fatty acids (FAs) in organs as well as lipid homeostasis remains unclear enough. In this study, rats are randomly divided into a control group (CN), a high-colleseed oil group (COG), and a high-sunflower oil group (SOG). FAs profile in liver and visceral fats of rats in two high-fat (HF) diet groups is compared with that in CN. Oleic, γ-linolenic, eicosadienoic, and arachidonic acid accumulate in COG liver or visceral fats, but the levels of linoleic, eicosadienoic, docosanoic, and dihomo-γ-linolenic acid decrease in COG visceral fats. However, these FAs levels increased in SOG liver or visceral fats except dihomo-γ-linolenic and arachidonic acid which changed insignificantly. The trend of initial upregulation and then downregulation of lipid metabolism-related genes expression is noted in COG liver, including stearoyl-CoA desaturase. Upregulation of adiponectin (ADPN) expression in visceral fats and downregulation of ADPN receptor 2 (Adipo-R2) expression in livers of both HF groups are observed. Correlation analysis revealed positive correlations between specific FAs content and ADPN expression level. Negative correlations are observed between Adipo-R2 expression and the content of oleic, linoleic, and γ-linolenic acid in the SOG liver. Practical applications: Dietary fat not only provides energy but is also associated with lipid homeostasis. In this work, the authors investigate the distribution of fatty acids (FAs) in vivo and their influence on genes related to lipid metabolism induced by diets enriched in oleic acid or linoleic acid. The study suggests that dietary fats modulate lipid homeostasis not only by regulating endogenous FAs levels but also by affecting the expression of genes related to lipid metabolism. This study may support the research in lipid nutrition and rational intake of dietary fat.     

Detection of Small Quantities of Higher Saturated Fatty Acids in Mixed Fatty Acids of Oils by Lead Salt Separation and Thin-Layer Chromatography

A combination of Twitchell's lead salt separation procedure and reverse phase thin-layer chromatography on Plaster of Paris plates has enabled easy separation and identification of C₂₀-C₂₄ minor saturated acids in mustard seed oils. This has further demonstrated the inapplicability of Bellier's turbidity point test for mustard oils by showing the quantitative variation in the proportion of C₂₀-C₂₄ acids naturally present in these oils. Expected augmentation of minor acid spots in chromatograms could be shown by adulteration with groundnut oil. The method can be adapted for the detection of adulteration of fats and oils.     

Impact of Free Fatty Acids and Phospholipids on Reverse Micelles Formation and Lipid Oxidation in Bulk Oil

Association colloids such as phospholipid reverse micelles could increase the rate of lipid oxidation in bulk oils. In addition to phospholipids, other surface active minor components in commercial oils such as free fatty acids may impact lipid oxidation rates and the physical properties of reverse micelles. In this study, the effects of free fatty acids on changes in the critical micelle concentration (CMC) of 1,2-Dioleoyl-sn-glycero-3-phosphocholine (DOPC) in stripped corn oil (SCO) were determined by using the 7,7,8,8-tetracyanoquinodimethane solubilization technique. Different free fatty acids including myristoleic, oleic, elaidic, linoleic and eicosenoic were added at 0.5 % by wt along with the DOPC into the bulk oils. There was no significant effect of free fatty acids with different chain length, configuration and number of double bonds on the CMC value for DOPC in bulk oil. However, increasing concentrations of oleic acid (0.5 to 5 % by wt) caused the CMC value for DOPC in bulk oils to increase from 400 to 1,000 μmol/kg oil. Physical properties of DOPC reverse micelles in the presence of free fatty acids in bulk oils were also investigated by the small angle X-ray scattering technique. Results showed that free fatty acids could impact on the reverse micelle structure of DOPC in bulk oils. Moreover, free fatty acid decreased pH inside reverse micelle as confirmed by the NMR studies. The oxidation studies done by monitoring the lipid hydroperoxide and hexanal formation revealed that free fatty acids exhibited pro-oxidative activity in the presence and absence of DOPC. Different types of free fatty acids had similar pro-oxidative activity in bulk oil.     

Plasma Lipid Peroxidation and Vitamin E Supplementation during High Intakes of Fish-Oil Fatty Acids

High intakes of fish oil concentrates (15g/day MaxEPA) resulted in increased TBARS in plasma after 2 weeks irrespective of the vitamin E intake and plasma content. After 4 weeks TBARS values returned to normal despite continued MaxEPA supplementation and different vitamin E levels. Fish oil supplements resulted in increased whole-blood aggregation and higher plasma glucose concentrations which did not occur when extra vitamin E was given. No significant differences in plasma cholesterol levels were observed.     

Levels of Lipid Peroxidation in Human Plasma and Erythrocytes: Comparison between Fatty Acids and Cholesterol

Lipid peroxidation has gained renewed attention with increasing evidence showing its biological role in producing toxic compounds and cellular signaling mediators. The assessment of lipid peroxidation levels in vivo is difficult partly because lipids are oxidized by different oxidants by different mechanisms to give versatile types of products, which may undergo metabolism and secondary reactions. In the present study, total hydroxyoctadecadienoic acids (tHODE) and 7α- and 7β-hydroxycholesterol (t7-OHCh) from 44 healthy human subjects were assessed as biomarkers after reduction with sodium borohydride followed by saponification with potassium hydroxide comparing with the prevailing standard 8-isoprostaglandin F_2α (t8-iso-PGF_2α). The average concentrations of tHODE, total 8-isoprostaglandin F_2α (t8-iso-PGF_2α), t7α-OHCh, and t7β-OHCh were 203, 0.727, 87.1, and 156 nmol/l plasma and 1,917, 12.8, 1,372, and 3,854 nmol/l packed erythrocytes, respectively. The ratios of tHODE and t7-OHCh to the parent substrates were 194 and 3,519 μmol tHODE/mol linoleates and 40.9 and 686 μmol t7-OHCh/mol cholesterol in plasma and erythrocytes, respectively. It was found that (1) t7-OHCh in blood was unexpectedly high, as high as or even higher than tHODE, (2) the amounts of tHODE was more than 100 fold higher than t8-iso-PGF_2α (3) the level of lipid oxidation products in erythrocytes was higher than that in plasma, and (4) lipid peroxidation products level tended to increase while antioxidant level decrease with age. These products may be used as potential biomarker for assessment of lipid peroxidation and oxidative stress in vivo.