Reduction Of Linoleic Acid Research Articles

Arabidopsis seeds altered in the circadian clock protein TOC1 are characterized by higher level of linolenic acid

The circadian clock plays a critical role in regulating plant physiology and metabolism. However, the way in which the clock impacts the regulation of lipid biosynthesis in seeds is partially understood. In the present study, we characterized the seed fatty acid (FA) and glycerolipid (GL) compositions of pseudo-response regulator mutants. Among these mutants, toc1 (timing of cab expression 1) exhibited the most significant differences compared to control plants. These included an increase in total FA content, characterized by elevated levels of linolenic acid (18:3) along with a reduction in linoleic acid (18:2). Furthermore, our findings revealed that toc1 developing seeds showed increased expression of genes related to FA metabolism. Our results show a connection between TOC1 and lipid metabolism in Arabidopsis seeds.

Breeding of high seed oil oleate levels into Upland cotton from wild Gossypium barbadense L. germplasm

AbstractA high seed oil oleate trait identified in wild Gossypium barbadense L. cotton accession GB713 (PI 608139) was bred into Upland cotton (Gossypium hirsutum L.) cultivar Sure‐Grow 747 (SG747, PVP 9800118). Starting from the F2 generation of an initial cross between GB713 and SG747, plants were selected by measuring the seed oil fatty acid distributions by gas chromatography. Selected F3 plants were crossed to M Rk‐Rn 6, a line previously created from GB713 and SG747 for improved nematode resistance. High‐oleate plants were selected in the F2 population. Selected plants were then crossed to HOa1 (a ∼35% oleate line derived from M Rk‐Rn 1, a sibling line to M Rk‐Rn 6), and high‐oleate plants were again selected in the F2 population. F3 plants were re‐selected for the high‐oleate trait, and four selected F4 lines were evaluated in 2022 field plots. The four lines had oleate levels between 52% and 57%, approximately triple that found in normal cottonseed oil (15%–19%) and higher than in either the high‐oleate wild GB713 parent (∼40%) or in the previously released HOa cotton plant lines (33%–35%). The increased oleate levels occurred with an approximately equal reduction in linoleic acid. Other seed and fiber properties were largely like those of SG747, although some residual GB713 character existed within the lines. The resulting oil composition should be ideal for use in deep fat frying, with the high level of oleic acid improving the oil's oxidative stability but with sufficient linoleic acid to maintain frying flavor.

Quality of oil extracted by cold press from Nigella sativa seeds incorporated with rosemary extracts and pretreated by microwaves

Abstract Black cumin (Nigella sativa) seed (BS) oil has high a peroxide value (PV) and acid value (AV). In this study, BS was incorporated with different levels of rosemary extracts as a natural antioxidant source before and after pretreatment by microwaves. Based on the oil extraction yield (33%), PV (8.4 meq O2 per kg oil), and AV (3.2 mg KOH per gram oil), the optimum condition was determined as microwave radiation for 120 s and, after that, moisturizing by the extract at 4% level. AV and PV were lower, and chlorophylls, carotenoids, polyphenols, thymoquinone, and tocopherols content were higher in oil extracted from pretreated BS than oil extracted from control BS. Reduction and loss of bioactive components occurred in oil samples during the 120 days of storage; however, it was higher in the control sample. There were no significant differences (p < 0.05) in the fatty acid composition of oil samples; however, oxidation and reduction of linoleic acid in the control oil sample were higher (4.2%) than the oil extracted from pretreated BS (2.5%). In conclusion, the oil extracted from the pretreated BS had higher oil extraction yield, high bioactive components, and stability; therefore, microwave radiation and incorporation of rosemary extract before oil extraction from BS is suggested.

Targeted metabolomics reveals fatty acid abundance adjustments as playing a crucial role in drought-stress response and post-drought recovery in wheat.

Drought stress is one of the abiotic stresses restricting plant development, reproductive growth, and survival. In the present study, the effect of drought stress and post-drought recovery for the selected local wheat cultivar, Atta Habib, was studied. Wheat was grown for 16days followed by drought stress for 7days and allowed to recover for 7days after the removal of the drought stress. Same-aged untreated plants were also grown as a control. The effect of drought stress and post-drought recovery on morphology (root length, shoot length, root weight, and shoot weight), enzymatic activity, and fatty acid profile were analyzed. The results showed that shoot weight (93.1mg), root weight (85.2mg), and shoot length (11.1cm) decreased in the stressed plants but increased steadily in the recovered plants compared to the same-aged control plants, while root length showed a higher increase (14.0cm) during drought stress and tended to normalize during the recovery phase (13.4cm). The ascorbate peroxidase activity increased in the stressed plants (5.44unit/mg protein) compared to the control, while gradually normalizing in the recovery phase (5.41unit/mg protein). Gas chromatography coupled mass spectrometric analysis revealed abundance changes in important fatty acids, such as palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid. Palmitic acid (39.1%) and oleic acid (2.11%) increased in the drought-stressed plants, while a reduction in linoleic acid (6.85%) and linolenic acid (51.18%) was observed compared to the same-aged control plants, i.e., palmitic (33.71%), oleic (0.95%), linoleic (7.52%), and linolenic acid (55.23%). The results suggest that wheat tries to recover in the post-drought stage by repairing oxidative damage through ascorbate peroxidase, and by adjusting fatty acid abundances under drought stress and during the post-drought phase in an effort to maintain membranes' integrity and a suitable fat metabolism route, thus helping recovery. Targeted metabolomics may be further used to explore the role of other metabolites in the drought-stress response mechanism in wheat. Furthermore, this relatively little explored avenue of post-drought recovery needs more detailed studies involving multiple stress durations.

Influence of germ storage from different corn genotypes on technological properties and fatty acid, tocopherol, and carotenoid profiles of oil

The objective was to evaluate the influence of germ storage (0, 30, and 60 days) from different corn genotypes (yellow floury, white floury, and yellow flint corn) on technological properties and fatty acid, tocopherol, and carotenoid profiles of oil. There was an increase in γ-tocopherol, lutein, zeaxanthin, and cryptoxanthin in yellow flint corn oil according to the increase of storage time. There was a reduction in linoleic acid in yellow floury and flint corn oils as the storage time increased. There was a reduction in γ-tocopherol and lutein in yellow and white floury corn as the storage time increased. The α-tocopherol decreased during storage in all genotypes. Yellow flint corn is indicated for extraction of oil due to the great conservation of germ during storage and higher content of carotenoids. White floury corn, despite having a higher content of tocopherols in oil, showed higher degradation during storage which increases the production costs of oil.

Research on the Antioxidant Effects of Olive (Olea europaea L.) Leaf Using by in vitro Methods#

In this study, antioxidant properties of olive (Olea europaea L.) leaves containing oleuropein were investigated in n-hexane, ethyl acetate, and methanol based extracts obtained from dried olive leaves at different concentration by various in vitro methods. Percentage yields of the O. europaea were found for the n-hexane extract 13.21%, for ethyl acetate extract 26.15% and for methanol extract 34.59%, respectively. Total phenolic substance content (85.27±15.03%), linoleic acid reduction (89.52±9.77%) and reduction capacity (1.49±0.03) were the highest in the methanol extract. Finally, the DPPH radical scavenging efficiency (72.93±0.42%), reduction of iron (II) ions (50.53±5.53%) and superoxide radical scavenging activity (72.93±0.42%). were the highest in the ethyl acetate extract. In conclusion, it was seen that total phenolic substances, linoleic acid reduction and reduction capacity of the methanol extract of the antioxidant activity of the O. europaea was more active when equated with n-hexane and ethyl acetate extracts. Also, it was found out that the ethyl acetate extract was more effective in DPPH radical scavenging, iron reduction, linoleic acid reduction and superoxide radical scavenging activity. According to the data obtained, it is thought that olive leaf might be evaluated as a natural and cheap alternative antioxidant in different fields such as food, cosmetic, pharmaceutical industry and animal nutrition.

Effect of flaxseed oil supplementation on the erythrocyte membrane fatty acid composition and endocannabinoid system modulation in patients with coronary artery disease: a double-blind randomized controlled trial

BackgroundThe endocannabinoid system (ECS) overactivation, associated with increased inflammatory process, may act as a risk factor for coronary artery disease (CAD). Dietary fat may influence the ECS tone. The aim of the present study was to investigate the effect of flaxseed oil on the erythrocyte membrane fatty acid profile and ECS activity by the measurement of serum N-arachydonoil ethanolamine (AEA) and cannabinoid receptor type-1 (CB1), cannabinoid receptor type-2 (CB2), and fatty acid amide hydrolase (FAAH) mRNA expression.MethodsThis clinical trial was performed on 44 patients with CAD. The intervention group received 1.5% fat milk supplemented with flaxseed oil (containing 2.5 g α-linolenic acid or ALA), while the placebo group received 1.5% fat milk for 10 weeks. The fatty acid profile of erythrocyte membrane phospholipids was measured by gas chromatography. The AEA level was determined using an ELISA kit, and real-time PCR was performed to measure CB1, CB2, and FAAH mRNA expression pre- and post-intervention.ResultsFlaxseed oil supplementation resulted in a significant increase in the ALA content and a significant reduction in linoleic acid (LA) content of membrane phospholipids, compared to the placebo group (MD = − 0.35 and 2.89, respectively; P < 0.05). The within group analysis showed that flaxseed oil supplementation caused a significant reduction in both LA and arachidonic acid (MD = − 4.84 and − 4.03, respectively; P < 0.05) and an elevation in the ALA (MD = 0.37, P < 0.001) content of membrane phospholipids compared with the baseline. In the intervention group, a marked reduction was observed in the serum AEA level after 10 weeks of intervention, compared with the placebo group (MD = 0.64, P = 0.016). Changes in CB2 mRNA expression in the flaxseed oil group were significant (fold change = 1.30, P = 0.003), compared with the placebo group.ConclusionFlaxseed oil supplementation could attenuate the ECS tone by decreasing the AEA level and increasing CB2 mRNA expression. Therefore, flaxseed oil may be considered a promising agent with cardioprotective properties.

Roles of microbes and lipolytic enzymes in changing the fatty acid profile, α-tocopherol and β-carotene of whole-crop oat silages during ensiling and after exposure to air

The aim of present study is to clarify the roles of microbes, lipase and lipoxygenase in changes of fatty acids (FA) profile, α-tocopherol and β-carotene of whole-crop oat silages treated without (Control) or with Lactobacillus plantarum (LP) and propionic acid additive (PA) during ensiling and aerobic exposure. Whole-crop oat was harvested from the 8 fields (1000 m2 per field) and mixed as a pile which was then separated into 12 piles in the laboratory. The 12 piles (630 g per pile) were randomly ensiled with above additive treatments. Four piles per additive treatment were separately filled into 4 experimental silos (polyvinyl chloride bottle, 1 L), immediately. After ensiling for 65 d at room temperature, a part of silages (200 g) was sampled and the others (420 g) were exposed to air for 4 d. The increase of palmitic acid, reduction of linoleic acid and α-linolenic acid, and β-carotene loss occurred in the control silage because of bio-hydrogenation of lactic acid bacteria, lipase responsible for degrading lipid into FA, and lipoxygenase in charge of degrading β-carotene, linoleic acid and α-linolenic acid after ensiling. Compared with the control silage, an increase in linoleic acid content was found in LP-treated silage because LP increased the activity of lipase; Moreover, higher activity of lipoxygenase resulted in big losses of α-linolenic acid and β-carotene in LP-treated silage. In PA-treated silage, effects of lipase and lipoxygenase on changing the contents of linoleic acid and α-linolenic acid were not found, and slight loss of β-carotene was observed. During aerobic exposure for 4 d, multiplication of aerobic bacteria and yeasts resulted in most of FA and β-carotene loss and increased α-tocopherol content in all treatments. Compared with the control and LP-treated silages, PA relieved loss of β-carotene and reductions of linoleic acid and α-linolenic acid, because PA restrained the multiplication of aerobic bacteria and yeasts. In conclusion, lipase had a contribution in increasing contents of palmitic acid and linoleic acid during ensiling, and microbes played a potential role in increasing α-tocopherol content before aerobic deterioration in the present study.

Influence of high-dose gamma radiation and particle size on antioxidant properties of Maize ( Zea mays L.) flour

Influence of high-dose gamma radiation and particle size on antioxidant properties of maize (Zea mays L.) flour was studied using response surface methodology. A central composite design based on three levels of each of particle size, in terms of mesh number (40, 60 and 80 meshes), and gamma radiation dose (25, 50 and 75 kGy) was constructed. A statistically significant dose-dependent decrease (p<0.05) in antioxidant properties of gamma irradiated flour was observed. However, an increase in the mesh number (decrease in particle size of flour) resulted in an increase in antioxidant properties. The optimum level of radiation dose to achieve maximum value of responses was found to be 50 kGy for Trolox equivalent total antioxidant activity (TETAOA), 25 kGy for iron chelating ability (ICA), 25 kGy for reducing power (RP) and 75 kGy for linoleic acid reduction capacity (LARC). However, the optimum level of mesh number to achieve desired levels of TETAOA, ICA, RP and LARC was found to be 80 meshes.

Physico-chemical Characteristics and Oxidative Stability of Date-Pits Oil during Storage at Different Temperatures

Abstract In this study, oxidative stability of date-pits (i. e. Khalas variety) was investigated during storage as a function of temperature. The stability of date-pits oil was determined by measuring acid value (AV), peroxide value (PV), p-anisidine value (PAV), tocopherol and oxidative stability index. Initial characteristics of oil were assessed by measuring its physico-chemical and melting characteristics, fatty acids composition and aflatoxin. Storage of date-pits caused highest reduction in linoleic acid (C18:2, ω6) followed by oleic acid (C18:1, ω9). AV, PV and PAV of the fresh oil were 1.41 mg KOH/g oil, 3.30 meq/kg oil and 0.60, respectively. These values increased linearly at slower rate in the case of 30 °C storage, while sharp rise was observed after 40 days in cases of 100 and 150 °C storage (p &lt; 0.05). The results of this study indicate that date pits oil had a good oxidative and thermal stability and could thus be used to develop value-added food ingredients.

Application of esterase inhibitors: A possible new approach to protect unsaturated fatty acids from ruminal biohydrogenation

General nutritional guidelines recommend reducing the consumption of fats originated from ruminant products. This is due to the ruminal biohydrogenation of unsaturated fatty acids (UFAs) which leads to the presence of unhealthy saturated or trans fats in ruminant products. Here, for the first time to our knowledge, we have focused on the main biochemical process which results in the saturation of UFAs. Rumen lipolytic activity (RLA) generates non‐esterified fatty acids (NEFAs) in the rumen, which are a prerequisite for the biohydrogenation process to occur. We have examined different concentrations of pyridostigmine bromide (PB), of reversible cholinesterase inhibitor, in batch cultures containing 80 mg soybean oil, as a source of triglyceride. PB is the main active compound of an FDA approved drug for the treatment of myasthenia gravis and also pretreatment against nerve gas in humans. Our hypothesis was to evaluate PB as an inhibitor for RLA. In normal conditions, soon after triglycerides enter the rumen, they are hydrolyzed as a result and free fatty acids undergo the biohydrogenation process. Our results indicated that no significant (P &gt; 0.01) reduction in linoleic acid (C18:2, ω6) after 6 h incubation was observed for cultures containing PB with concentrations above 0.052 g/dL. We concluded that PB has the potential to inhibit RLA in cultures after 6 h of incubation. Such findings suggest the potential of PB to be utilized in vivo as a feed additive to inhibit biohydrogenation of unsaturated fatty acids in the rumen.Practical applications: The biohydrogenation of health benefitial unsaturated fatty acids in the rumen cause ruminant products, such as milk and meat, to contain highly saturated fats. Inhibition of rumen microbial lipolytic activity in vivo could increase the flow of unsaturated fatty acids for absorption and therefore, would have the potential to improve fatty acid composition of ruminant milk and meat. This would also have benefits for the animal.In normal ruminal fermentation, unsaturated fatty acids are hydrolyzed as a result of rumen lipolytic activity. Hydrolysis of lipids and production of non‐esterified fatty acids are prerequisite for biohydrogenation of unsaturated fatty acids. We have applied esterase inhibitors in vitro to investigate whether it is possible to block rumen lipolytic activity or not. Our objective was to introduce a new method to bypass unsaturated fatty acids to small intestine.

English

Sunflower oil is extensively used in frying in Algeria as an alternative to olive oil due to its low cost. However, the high level of unsaturated fatty acids (FA) contained in sunflower oil enhances its susceptibility to oxidation. In our study, the sunflower oil was heated at 99&plusmn;2&deg;C with incorporation of 9 L of oxygen/second for 52 h continuously in the absence of foodstuff. Heating polyunsaturated fatty acids (PUFAs) in the presence of air causes a greater degree of lipid peroxidation. The oil oxidation degree was monitored through several physicochemical analyses. The products of thermal oxidation were monitored using UV- spectrophotometric method and Fourier transform infrared spectroscopy (FT-IR). Compared to fresh oil, the free-fatty acid contents, peroxide value, density and moisture of the thermally oxidized sunflower oil increased. In addition, the iodine and saponification values decreased during thermal treatment. The treatment applied had a negative effect on FA composition; the most significant effects were on C18:2, C18:1 and C16:0 contents. Analysis of chromatographic profile of thermoxidized sunflower oil showed a reduction in linoleic acid (LA) and an increase in oleic and palmitic acids; decrease of linoleic acid content is used as an indicator of lipid oxidation. Moreover, during the early stages, conjugated dienes (CDs), absorbing at 233 nm, were formed upon decomposition of hydroperoxides. In our study, the early stages of lipid oxidation were measured by UV-spectrophotometric method. Hydroperoxides broke down into secondary products and were revealed by FT-IR; these scission products are generally odoriferous by nature. The C=O stretching band at 1739-1724 cm-1 of the aldehydes was much more intense. Formation of conjugated double bond systems and the isomerisation of cis to trans double bonds was observed in the C=C stretching region at 980 to 965 cm-1. The results obtained reveal that even fresh oil contains products of peroxidation and isomerization of C18:2, n-6; indeed, CDs can be produced during the refining process of oil. The treatment applied increased the rate of these products and conferred a marked rancid taste and a thick texture to the thermoxidized sunflower oil. &nbsp; Key words: Sunflower oil, Linoleic acid, thermally oxidative treatment, alteration level.&nbsp;

Genetic improvement for oil quality through induced mutagenesis in groundnut (Arachis hypogaeaL.)

The present research was aimed towards oil quality improvement in two groundnut cultivars (GPBD-4 and TPG-41) through induced mutagenesis using EMS and gamma rays. Six hundred true breeding mutants were isolated in M3 and were characterized for fatty acid profile at M4/M5 generations. Twenty high oleate mutants showing consistent fatty acid profile across the generations were further evaluated for economic traits. The induced variability was skewed towards high levels of oleic acid and low level of linoleic acid in GPBD-4 and it was reverse in TPG-41. Greater magnitude of induced variability was found for oleic acid (37.40–75.16%), linoleic acid (9.01–40.30%) and oleic to linoleic acid ratio (O/L) (0.95–8.34) in mutant populations at M5. Mutant, GE-113 recorded the highest increase in oleic acid (74.48%), lowest reduction in linoleic acid (9.17%) and highest increase in O/L ratio (8.12) compared to parent GPBD-4. High oleate mutants were having reduced levels of palmitic acid, long chain saturated fatty acids and iodine value and were comparable to parents for economic traits. Mutant GE-113 had pod yield of 25.33 qt/ha comparable to GPBD-4 (27.06 qt/ha).

Specialty Fats Enriched with Behenic and Medium Chain Fatty Acids from Palm Stearin by Lipase Acidolysis

AbstractStructured lipids containing behenic and medium chain (MC) fatty acids were prepared from palm stearin using 1,3‐specific lipase‐catalyzed acidolysis. Incorporation of MC and behenic acids was affected by proportion of substrate, type of fatty acids, reaction time, addition of water and quantity of lipase. It was found that incorporation of caproic acid was less compared to other longer chain fatty acids. Caprylic, capric and behenic acids shared similar incorporation (up to 32 %), which increased with the amount of fatty acids added and the time of reaction. The incorporation of these acids increased with addition of 1 % moisture and the increasing amount of enzyme from 5 to 10 % at the beginning of the reaction. Incorporating behenic and MC fatty acids, reduced palmitic and oleic acids considerably from palm stearin, the extent being the same as those incorporated. However, the reduction of linoleic acid was marginal. The solid fats content of the modified palm stearin containing MC and behenic acids were reduced at all temperatures due to a reduction in higher molecular weight triglycerides and an increasing proportion of lower chain triglycerides. The modified products of palm stearin with added capric and behenic acids were similar to commercial bakery shortenings and those with added capric acid were like salad or cooking oils or butter in melting characteristics.

Starch and oil in the donor cow diet and starch in substrate differently affect the in vitro ruminal biohydrogenation of linoleic and linolenic acids

Trans isomers of fatty acids exhibit different health properties. Among them, trans-10,cis-12 conjugated linoleic acid has negative effects on milk fat production and can affect human health. A shift from the trans-11 to the trans-10 pathway of biohydrogenation (BH) can occur in the rumen of dairy cows receiving high-concentrate diets, especially when the diet is supplemented with highly unsaturated fat sources. The differences of BH patterns between linoleic acid (LeA) and linolenic acid (LnA) in such ruminal conditions remain unknown; thus, the aim of this work was to investigate in vitro the effects of starch and sunflower oil in the diet of the donor cows and starch level in the incubates on the BH patterns and efficiencies of LeA and LnA. The design was a 4 × 4 Latin square design with 4 cows, 4 periods, and 4 diets with combinations of 21 or 34% starch and 0 or 5% sunflower oil. The rumen content of each cow during each period was incubated with 4 substrates, combining 2 starch levels and either LeA or LnA addition. Capillary electrophoresis single-strand conformation polymorphism of incubates showed that dietary starch decreased the diversity of the bacterial community and the high-starch plus oil diet modified its structure. High-starch diets poorly affected isomerization and first reduction of LeA and LnA, but decreased the efficiencies of trans-11,cis-15-C18:2 and trans C18:1 reduction. Dietary sunflower oil increased the efficiency of LeA isomerization but decreased the efficiency of trans C18:1 reduction. An interaction between dietary starch and dietary oil resulted in the highest trans-10 isomers production in incubates when the donor cow received the high-starch plus oil diet. The partition between trans-10 and trans-11 isomers was also affected by an interaction between starch level and the fatty acid added to the incubates, showing that the trans-10 shift only occurred with LeA, whereas LnA was mainly hydrogenated via the more usual trans-11 pathway, whatever the starch level in the substrate, although the bacterial communities were not different between LeA and LnA incubates. In LeA incubates, trans-10 isomer production was significantly related to the structure of the bacterial community.

Epidermal FABP (FABP5) Regulates Keratinocyte Differentiation by 13(S)-HODE-Mediated Activation of the NF-κB Signaling Pathway

Fatty acid-binding proteins (FABPs) are postulated to serve as lipid shuttles that solubilize hydrophobic fatty acids and deliver them to appropriate intracellular sites. Epidermal FABP (E-FABP/FABP5) is predominantly expressed in keratinocytes and is overexpressed in the actively proliferating tissue characteristic of psoriasis and wound healing. In this study, we found decreased expression of the differentiation-specific proteins keratin 1, involucrin, and loricrin in E-FABP(-/-) keratinocytes relative to E-FABP(+/+) keratinocytes. We also determined that incorporation of linoleic acid was significantly reduced in E-FABP(-/-) keratinocytes. Although linoleic acid did not directly affect keratinocyte differentiation, keratin 1 expression was induced by the linoleic acid derivative 13(S)-hydroxyoctadecadienoic acid (13(S)-HODE), and this induction was concomitant with increased NF-κB activity. In E-FABP(-/-) keratinocytes, the expression of 13(S)-HODE and the subsequent induction of NF-κB activity was lower than in wild-type keratinocytes. The reduction of linoleic acid in E-FABP(-/-) keratinocytes led to decreased cellular 13(S)-HODE content, resulting in decreased keratin 1 expression through downregulation of NF-κB activity. The regulation of fatty acid metabolism by E-FABP during keratinocyte differentiation suggests that E-FABP may have a role in the pathogenesis of psoriasis.

Red blood cell and adipose tissue fatty acids in mild inactive multiple sclerosis

The fatty acid profiles of phosphatidyl ethanolamine (PE) and phosphatidyl choline (PC) of the red blood cells of 30 patients with mild inactive multiple sclerosis (MS) and 30 healthy controls were studied by gas chromatography. The groups were well matched for factors likely to influence tissue lipid levels, including diet. The MS patients showed a significant reduction in PE eicosapentaenoic acid (p = 0.009) especially in women, and an increase in both PE dihomo-gamma-linolenic acid (p = 0.004) and PC stearic acid (p = 0.04). No reduction in linoleic acid was observed in either the PC or PE fractions of the MS subjects. A similar study of the fatty acid profile in adipose tissue in 26 MS and 35 healthy controls found no detectable eicosapentaenoic acid in either group. However, whereas docosahexaenoic acid was not detectable in any MS patient, 40% of the controls had measurable levels varying from to 0.1 to 0.3% of total estimated fatty acid (p = 0.0003). No reduction in linoleic acid in MS subjects was observed. Supplementation with oral fish body oil demonstrated that n-3 fatty acids were incorporated into red blood cells over 5 weeks and this occurred equally in MS and controls. The effects of oral supplementation on adipose tissue were studied after 1 and 2 years. Whereas many fatty acids such as linoleic acid were raised at 1 year, but did not rise subsequently, eicosapentaenoic acid and docosahexaenoic acid continued to rise through the 2-year period.(ABSTRACT TRUNCATED AT 250 WORDS)

Enhancement of the oxidative stability of some vegetable oils by blending with Moringa oleifera oil

Blends (20%, 40%, 60%, 80% w/w) of Moringa oleifera oil (MOO) with sunflower oil (SFO) and soybean oil (SBO) were prepared to evaluate the changes in fatty acid (FA) composition, oxidative and thermal stability of SFO and SBO. The blending of MOO with SFO and SBO in proportions of 0–80% resulted in the reduction of linoleic acid (C 18:2) content of SFO and SBO from 67.0% to 17.2% and 56.2% to 14.6% and increase in the contents of oleic acid (C 18:1) from 26.2% to 68.3% and 21.4% to 65.9%, factors of 0.72, 0.72 and 1.27, 1.33, respectively. A storage ability test (180 days; ambient conditions) showed an appreciable improvement in the oxidative stability of substrate oils with increase of MOO concentration, as depicted by the least oxidative alterations in PV, IV and highest increase in induction period, IP, of the MOO:SBO (80: 20 w/w) blend. Each 20% addition of MOO resulted in decreases of PV and IV by factors of 0.84, 0.85 and 0.89, 0.88, respectively, and increases in IP by factors of 1.45 and 1.37 of SFO and SBO, respectively. The heating performance test (180 °C for 42 h; 6 h heating cycle per day), as followed by the measurement of polymer contents and total polar contents (TPC), also revealed the MOO:SBO (80:20 w/w) blend to be the most stable. Every 20% addition of MOO in SFO and SBO resulted in reduction of the polymer contents and TPC of SFO and SBO by factors of 0.91, 0.92 and 0.94, 0.94, respectively. On the basis of the present findings, it appears that proper blending of high linoleic oils with MOO can result in oil blends which could meet nutritional needs with improved stability for domestic cooking and deep-frying.

Remodeling of phospholipid fatty acids in mitochondrial membranes of estivating snails.

The effects of estivation on the phospholipid-specific fatty acid composition of mitochondrial membranes in the hepatopancreas of the terrestrial snail Cepaea nemoralis were investigated. The fatty acid composition of all phospholipids was significantly altered in snails estivating for 6 wk, indicating that substantial remodeling occurs. The most profound changes occurred in cardiolipin (CL). CL of estivating snails was 13-fold more saturated, contained 9-fold more monoenes, and had 45% fewer polyenes than in active snails. These differences were due, in part, to a reduction in linoleic acid (1 8:2n-6) content of CL from estivators. As in mammals, CL of active snails appears to preferentially incorporate 18:2n-6, which accounts for 60% of the acyl chains in this phospholipid. This proportion was reduced by 50% in estivators. Changes in the fatty acyl content of other phospholipids of estivating snails included increased monoenes in phosphatidylethanolamine (PE) and phosphatidylinositol, reduced ratios of n-3/n-6 polyenes in PE and phosphatidylcholine (PC), and an increased n-3/n-6 ratio in phosphatidylserine (PS). Arachidonic acid (20:4n-6) levels were reduced in PS but increased in CL and PC. Taken together, these alterations to fatty acid composition are consistent with decreased biological activity of membrane-related processes which occur in conjunction with the reduction of mitochondrial aerobic metabolism observed during estivation.

VITAMIN C ATTENUATION OF THE DEVELOPMENT OF TYPE I DIABETES MELLITUS BY INTERFERON-α

Interferon alpha (IFN-α) inhibits insulin release and may be cytotoxic to pancreatic islets. Increased free radical activity may be implicated in the cytotoxic action of IFN-α and development of diabetes mellitus. Therefore we measured markers of free radical activity (lipid peroxides and the non-peroxide-conjugated diene isomer of linoleic acid [PL-9,11-LA′]) along with some pancreatic variables in male albino rats treated with IFN-α, as well as the possible protective effect of two antioxidants, vitamin C and mannitol. Compared to untreated rats, it was shown that IFN-α induced an increase in plasma glucose. Pancreatic and serum insulin, as well as serum C-peptide, were increased after 1 week, then their levels were reduced after 2 weeks. Plasma lipid peroxides and (PL-9,11-LA′) were markedly elevated, while linoleic acid was reduced. These changes in the studied parameters were attributed, in part, to the superoxide and free radical generation during IFN-α treatment. Plasma glucagon was increased after 2 weeks. Administration of vitamin C along with IFN-α succeeded in modulating most of the altered parameters affected during IFN-α. The hyperglycaemic effect of IFN-α was greatly ameliorated and the negative effect on pancreatic and serum insulin and serum C-peptide were nearly abolished. The elevated levels of lipid peroxide and (PL-9,11-LA′) and the reduction in linoleic acid being normalised. The only persistent effect was the increase in plasma glucagon. Concurrent administration of mannitol with IFN-α caused no changes in the parameters studied compared to that induced by treatment with IFN-α alone.