Diunsaturated Fatty Acids Research Articles

Maize Grain Metabolite Profiling by NMR: Effects of Growing Year, Variety, and Cropping System.

Considering that maize (Zea mays L.) is a staple food for a large segment of the population worldwide, many attempts have been made to improve the nutritional value of its grain and at the same time to achieve sustainable cropping systems. The present study aimed to characterize the composition and nutritional value of maize grain as influenced by cropping system, genetic background (variety), and growing year using untargeted NMR metabolomics. The composition of both water- (sugars and polyols, organic acids, and amino acids) and liposoluble metabolites (free and esterified fatty acids, sterols, and lipids) extracted from the maize grain was determined. Multivariate statistical analyses (PCA and ANOVA) pointed to the growing year and the variety as the most important random and fixed factors, respectively, influencing the metabolite profile. The samples were separated along PC1 and PC3 according to the growing year and the variety, respectively. A higher content of citric acid and diunsaturated fatty acids and a lower content of tyrosine, trigonelline, and monounsaturated fatty acids was observed in the organic with respect to the conventional variety. The effect of the cropping system was overwhelmed by the random effect of the growing year. The results provide novel knowledge on the influence of agronomic practices on maize micronutrient contents.

Abstract 2873: Radiation therapy promotes polyunsaturated fatty acid mediated ferroptosis in cervical cancer: Role of AMPK/xCT/GPX4 axis

Abstract Purpose: Previously, we found that mono-and di-unsaturated fatty acids can sensitize cervical cancer to radiotherapy (RT) through a p53 dependent apoptotic mechanism that is distinct from ferroptosis (Muhammad et al., Cancer Res. 2022; 82: 4515-27). Polyunsaturated fatty acids (PUFAs) enhance therapeutic response in preclinical tumor models by increasing lipid peroxidation (L-ROS) and induction of ferroptosis. Ferroptosis is a form of cell death that requires abundant cytosolic labile iron to promote membrane lipid peroxidation. The objective of the present study is to test whether the combination of RT + PUFAs promotes cell death via increased membrane lipid peroxidation and ferroptosis in cervical cancer, and to determine the impact of RT + PUFAs on cervix tumor cell metabolism and mitochondrial function. Experimental Procedures: Cell viability and clonogenic cell survival assays were performed using 8 human cervical cancer cell lines including normal cervix epithelial controls incubated with PUFAs (EPA, DHA and AA), before and after RT. Western blotting, siRNA-mediated knockdown, pharmacologic inhibition and activation were performed to determine whether ferroptosis dependent signals were mediating PUFA-induced RT sensitivity. Oxidative stress parameters were quantified using mass spectrometry and fluorometric dyes. Flow cytometry was used to quantify total cell ROS, lipid ROS, mitochondrial ROS and labile iron pool. Mitochondrial morphology and function were characterized using microscopy and the Seahorse assay. Summary: PUFAs + RT increased total ROS and LROS accumulation followed by a ferroptotic tumor cell death, which was iron-dependent and could be prevented by the addition of iron chelator and lipophilic antioxidants, Ferrostatin-1 and Liproxstatin-1. GPX4, a thiol dependent enzyme that eliminates lipid peroxides, and the cystine-glutamate antiporter (xCT) a key source of cystine for reduced glutathione (GSH) synthesis, were downregulated in response to PUFAs + RT. PUFAs + RT induced increased mitochondrial ROS and subsequent metabolic dysfunction. Mechanistically, the expression of AMPK, a key regulator of metabolic/energy homeostasis and mitochondrial biogenesis, was upregulated by PUFAs + RT. Pharmacological activation and inhibition of AMPK further enhanced and abrogated the effect of PUFA + RT, respectively. Conclusions: PUFAs modify the RT sensitivity of cervical cancer cells by inducing cell death through ferroptosis and mitochondrial dysfunction via AMPK activation. In vivo experiments are ongoing in immunocompromised and immunodeficient mouse tumor models to confirm this finding and determine the impact of PUFAs on RT induced tumor cell death and anti-tumor immunity. Citation Format: Naoshad Muhammad, Nishanth Gabriel, Louise M. Bengtsson, Tyler McKinnish, Naomi Msengi, Kevin Cho, Gary Patti, Julie K. Schwarz. Radiation therapy promotes polyunsaturated fatty acid mediated ferroptosis in cervical cancer: Role of AMPK/xCT/GPX4 axis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2873.

Formation of Formic Acid and Its Esters in Oxidation of Fatty Acid Methyl Esters

Pathways of formation of low-boiling products in the course of oxidation of fatty acid methyl esters with atmospheric oxygen in a bubbling column were studied. These products are continuously removed from the reactor under the action of high temperature at continuous air supply. Two kinds of feedstock with different content of esters of mono- and diunsaturated fatty acids (methyl esters of fatty acids of olive and sunflower oils) were used in the study. Along with acids and aldehydes forming the major fraction of low-boiling products, compounds containing ester groups were detected. The 1Н and 13С NMR analysis revealed the presence of formic acid esters in the samples. The formate formation mechanism involving the Baeyer–Villiger reaction of aldehydes with hydroperoxides in the reaction volume was suggested.

Abstract 11443: Metabolic Profile Signature of Obesity in Heart Failure With Preserved Ejection Fraction

Introduction: Heart failure (HF) affects an estimated 6.2 million people in the US, with at least 50% of patients having HF with preserved ejection fraction (HFpEF). Obesity is a risk factor for HFpEF, however the association of obesity with metabolic signatures in HFpEF remains unclear. We aimed to identify unique metabolic profile of obesity among patients with HFpEF. Methods: A total of 41 participants from the Metabolomics, Oxidative Stress and Vascular Function (MOV) in HF study formed the discovery cohort, and 40 participants from the Atlanta Cardiomyopathy Consortium (TACC) study formed the validation cohort. All patients had HFpEF with left ventricular ejection fraction ≥ 50%. Untargeted high-resolution plasma metabolomic profiling identified 1,986 metabolic features. Partial least squares-discriminant analysis (PLS-DA) was performed separately in two cohorts to find the differently expressed metabolic features among obese (body mass index [BMI] ≥ 30 kg/m 2 ) vs. non-obese (BMI < 30 kg/m 2 ) patients with HFpEF. Variable Importance in Projection (VIP) score > 1 was used for feature selection. Annotation was performed by matching to an in-house library of previously confirmed metabolites. All features with VIP > 1 were used to explore pathway enrichment using Mummichog. Results: The MOV and TACC cohorts included 68.3% and 42.5% obese patients, respectively. The PLS-DA identified 23 metabolic features with confirmed annotations associated with obesity in the MOV, and 9 metabolic pathways were represented. Ten metabolites were validated in TACC, including 2,6-dihydroxypyridine, l-proline, taurine, l-methionine, guanine, 4-coumarate/phenylpyruvate, pyridoxamine, 1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline, ll-2,6-diaminoheptanedioate, and linoleate. One metabolic pathway, di-unsaturated fatty acid beta-oxidation, was validated. Conclusions: In two cohorts of HFpEF patients, by comparing the metabolic profiles of obese vs. non-obese patients, we identified alterations in amino acids, fatty acids, alkaloids, and vitamins. Moreover, pathway analysis confirmed alterations in the metabolic pathway of beta-oxidation of unsaturated fatty acids such as linoleate are also associated with obesity.

Neuropharmacological Alterations by a Rice Contaminant Stenotrophomonas maltophilia: a Detailed Bio-molecular and Mechanistic Landscape.

Contaminated rice is a major source of food poisoning in human communities where our earlier study showed Stenotrophomonas maltophilia, a Gram-negative bacillus, has been a major contaminant of the stored rice. In the present study, mono- and di-unsaturated fatty acids (UFAs) such as 18:1 ω 7 c, 16:1 ω 6 c, 16:1 ω 7 c, and 18:2 ω 6,9 c long-chain fatty acids have been found as the chief constituents of S. maltophilia boiled cell lysate. Throughout the study, both acute and chronic exposure of the cell lysate showed a decrease in the locomotor activity and a time-dependent increase of the depression (p < 0.001-0.0001, two-way ANOVA), supported by bioamine (dopamine, noradrenaline, adrenaline, serotonin, and GABA) depletion in rodents' brain possibly due to UFA-amino acid decarboxylase interaction favoring bioamine depletion as revealed by our study. Furthermore, the UFA-rich cell lysate revealed dose-dependent inhibition of murine brain microglial cell viability in vitro with concomitant increase of reactive oxygen species (ROS) inside the cell. Destruction of neuroprotective and neurotrophin releasing microglial cells, augmentation of brain ROS, and inflaming brain tissue resulting in infiltration of polymorphonuclear leucocytes also suggest to cause neurotoxicity by UFA derived from Stenotrophomonas maltophilia.

Long-Chain Fatty Acids in Bones and Their Link to Submicroscopic Vascularization Network: NMR Assignment and Relaxation Studies under Magic Angle Spinning Conditions in Intramuscular Bones of Atlantic Herring Fish.

The long-lasting proton signals in bones are identified as long-chain fatty acids, including saturated, mono-, and di-unsaturated fatty acids, with direct nuclear magnetic resonance evidence. We used intramuscular bones from Atlantic Herring fish to avoid interference from lipid-rich marrows. The key is to recognize that these signals are from mobile phase materials and study them with J-coupled correlation spectroscopies under magic angle spinning conditions. We kept extensive 1H-spin-echo records that allowed us to examine the effect of magic angle spinning on the transverse relaxation time of water and lipids over time. While it is impossible to distinguish based on chemical shifts, the relaxation data suggest that the signals are more consistent with the interpretation of phospholipid membranes than triglycerides in lipid droplets. In particular, the simultaneous T2 changes in water and lipids suggest that the centrifugal impact of magic angle spinning alters the lipid's structure in very tight spaces. Additional evidence of phospholipid membranes came from the choline-γ resonance at 3.2 ppm in fresh samples, which disappears with magic angle spinning. Thus, the fatty acid signals are at least partially from membrane bilayer structures, and we propose that they are linked to the submicroscopic vascularization channels similar to the dense canaliculi network in mammalian bones. Our detection of phospholipids from bones depended critically on two factors: (1) the elimination of the overwhelming triglyceride signals from marrows and (2) the preservation of water that biomembranes require. The relaxation data reveal aspects of lipid fluidity that have not been elucidated by previous order parameter studies on model membranes. Relaxation times have long been considered difficult to interpret. A robust and renewed understanding may be beneficial.

1H-NMR metabolomics reveals a multitarget action of Crithmum maritimum ethyl acetate extract in inhibiting hepatocellular carcinoma cell growth

Hepatocellular carcinoma (HCC) is nowadays the sixth cause of tumour-related deceases worldwide, estimated to become the third in Western countries by 2030. New drugs for HCC treatment still have many adverse effects. Several lines of evidence indicate that plant metabolites offer concrete opportunities for developing new therapeutic strategies for many diseases, including cancer. We previously reported that ethyl acetate extract of a spontaneous edible plant harvested in Apulia, Crithmum maritimum, significantly inhibited cell growth in HCC cells. By 1H-NMR spectroscopy, here we show that Crithmum maritimum ethyl acetate extract counteracts the Warburg effect, by reducing intracellular lactate, inhibits protein anabolism, by decreasing amino acid level, and affects membrane biosynthesis by lowering choline and phosphocholine. Also, we observed an effect on lipid homeostasis, with a reduction in triglycerides, cholesterol, monounsaturated fatty acids (MUFA), and diunsaturated fatty acids (DUFA), and an increase in polyunsaturated fatty acids (PUFA). Taken together, these data demonstrate that Crithmum maritimum-induced cytostasis is exerted through a multi-effect action, targeting key metabolic processes in HCC cells. Overall, our findings highlight the role of Crithmum maritimum as a promising tool for the prevention and the improvement of the therapeutic options for HCC and other types of tumours.

Identification and Quantitation of Hydroxy Fatty Acids in Fermented Sausage Samples.

The quality of fermented sausage is strongly influenced by its fatty acid (FA). However, the role of a defined starter culture in modifying sausage FA composition, and especially in the production of hydroxy FAs (HFAs), has not been determined. In this study, the FA compositions of sausages fermented with Latilactobacillus sakei, with L. sakei plus Staphylococcus carnosus, and with an aseptic control were characterized by liquid chromatography-mass spectrometry (MS)/MS and gas chromatography-MS. The sausages fermented with L. sakei, and with L. sakei plus S. carnosus, showed a reduced accumulation of poly and/or diunsaturated FAs and distinct composition of HFAs compared to the aseptic control. 2-HFAs were enriched via high-speed counter-current chromatography and identified uniquely in the L. sakei plus S. carnosus fermented sausage. Through lipid analyses, this study illustrated how the choice of a defined starter culture affected the observed FA metabolism in fermented sausages, facilitating the development of starter cultures or additives that impart desirable characteristics to sausage.

A bacterial biosynthetic pathway for methylated furan fatty acids

Fatty acids play many important roles in cells and also in industrial processes. Furan fatty acids (FuFAs) are present in the lipids of some plant, fish, and microbial species and appear to function as second messengers in pathways that protect cells from membrane-damaging agents. We report here the results of chemical, genetic, and synthetic biology experiments to decipher the biosynthesis of the monomethylated FuFA, methyl 9-(3-methyl-5-pentylfuran-2-yl) nonanoate (9M5-FuFA), and its dimethyl counterpart, methyl 9-(3,4-dimethyl-5-pentylfuran-2-yl) nonanoate (9D5-FuFA), in two α-proteobacteria. Each of the steps in FuFA biosynthesis occurs on pre-existing phospholipid fatty acid chains, and we identified pathway intermediates and the gene products that catalyze 9M5-FuFA and 9D5-FuFA synthesis in Rhodobacter sphaeroides 2.4.1 and Rhodopseudomonas palustris CGA009. One previously unknown pathway intermediate was a methylated diunsaturated fatty acid, (10E,12E)-11-methyloctadeca-10,12-dienoic acid (11Me-10t,12t-18:2), produced from (11E)-methyloctadeca-11-enoic acid (11Me-12t-18:1) by a newly identified fatty acid desaturase, UfaD. We also show that molecular oxygen (O2) is the source of the oxygen atom in the furan ring of 9M5-FuFA, and our findings predict that an O2-derived oxygen atom is incorporated into 9M5-FuFA via a protein, UfaO, that uses the 11Me-10t,12t-18:2 fatty acid phospholipid chain as a substrate. We discovered that R. palustris also contains a SAM-dependent methylase, FufM, that produces 9D5-FuFA from 9M5-FuFA. These results uncover the biochemical sequence of intermediates in a bacterial pathway for 9M5-FuFA and 9D5-FuFA biosynthesis and suggest the existence of homologs of the enzymes identified here that could function in FuFA biosynthesis in other organisms.

The main differences in reactivity of mono- and diunsaturated fatty acid esters during aerobic oxidation

During the aerobic oxidation of esters of both mono- and diunsaturated fatty acids and their mixtures, epoxide compounds are first forming, as well as the peroxide compounds with different structures and reactivities depending on the number of double bonds in the original molecule. The mild aerobic oxidation conditions in the column-type apparatus led to a number of features of the process. It was shown that both types of esters are consumed in independent ways, despite the fact that the whole process is radical. Therefore, this means the absence of processes of transfer of oxidation chains, as well as the chains of radical reactions themselves. Thus, we can conclude that the process under study is radical without chain transfer from one type of ester to another. Peroxides forming from monounsaturated fatty acid esters are able to participate in catalytic epoxidation by hydroperoxides, which proceeds with high selectivity. From diunsaturated fatty acid esters, at least two types of peroxides with different reactivities are formed. One of them can enter into catalytic epoxidation reaction, the other forms secondary oxidation products, which are mainly represented by the products of the Baeyer–Villiger reaction. In this contribution upon using different mono- and diunsaturated fatty acid esters, the mechanism of products formation has been investigated and discussed.

Fatty acid synthesis by Chlamydomonas reinhardtii in phosphorus limitation.

The importance of crucial nutrient factors like Phosphate (P) and their limited availability leads to variable fluctuations in fatty acid and phospholipid synthesis in the green alga. These fatty acids and phospholipids are an imperative byproduct of alga which used in biofuel production. The production of phospholipids in alga might be naturally enhanced by the optimized supplied by specific essential nutrient like Phosphate. In this study, green alga Chlamydomonas reinhardtii was cultivated in phosphate stress condition to obtain maximum phospholipids. In the stress condition, the organism exhibited variable changes in chlorophyll, fatty acid, and phospholipid compositions. These parameters analyzed by biomass, X-ray, GC, and TLC. Remarkably, saturated fatty acids, monounsaturated, and di-unsaturated fatty acids amounts, increases, while polyunsaturated fatty acids to decrease markedly. The maximum fatty acid content observed at 0.4 mgl-1 P content in growing media. A broad peak area of 56% of hexadecanoic acid (C 16:0) and followed by 28.8% linolenic (C18:3) was observed in GC analysis. These results indicate the essential fatty acid accumulation maximized at particular phosphate concentration in growing media. This necessary and essential fatty acid production from green algae in a sustainable manner is an inexpensive and excellent way for commercialization and biofuel production.

Effectiveness of the rapid test of polar compounds in frying oils as a function of environmental and compositional variables under restaurant conditions

Effect of fried food, oil type, moisture, fatty acid and molecular distribution on the effectiveness of rapid test of Total Polar Compounds (TPC) in frying oil based on dielectric constant was explored. Effects of all factors were compared and found to be significant (P < 0.05). Throughout the life cycle of frying oil, its rapid results were correlated well with those of conventional chromatography (Y = 0.7625X + 3.681, R2 = 0.8734). But the discrepancy was found within selected TPC ranges of 0%–10% and 20%–30%. According to the definition of TPC, three potential reasons for the high TPC values of fresh oils were discussed. For the deteriorated oils, the triglyceride dimers, mono-unsaturated and di-unsaturated fatty acids were found to be the main compositional factors by stepwise multivariate regression analysis. Pieces of advice about the operation guideline, internal control indices, calibration, reference oil, sensor, and detection range were proposed for instrument users and producers.

The Jellyfish Rhizostoma pulmo (Cnidaria): Biochemical Composition of Ovaries and Antibacterial Lysozyme-like Activity of the Oocyte Lysate.

Jellyfish outbreaks in marine coastal areas represent an emergent problem worldwide, with negative consequences on human activities and ecosystem functioning. However, potential positive effects of jellyfish biomass proliferation may be envisaged as a natural source of bioactive compounds of pharmaceutical interest. We investigated the biochemical composition of mature female gonads and lysozyme antibacterial activity of oocytes in the Mediterranean barrel jellyfish Rhizostoma pulmo. Chemical characterization was performed by means of multinuclear and multidimensional NMR spectroscopy. The ovaries of R. pulmo were mainly composed of water (93.7 ± 1.9% of wet weight), with organic matter (OM) and dry weight made respectively of proteins (761.76 ± 25.11 µg mg−1 and 45.7 ± 1.5%), lipids (192.17 ± 10.56 µg mg−1 and 9.6 ± 0.6%), and carbohydrates (59.66 ± 2.72 µg mg−1 and 3.7 ± 0.3%). The aqueous extract of R. pulmo gonads contained free amino acids, organic acids, and derivatives; the lipid extract was composed of triglycerides (TG), polyunsaturated fatty acids (PUFAs), diunsaturated fatty acids (DUFAs), monounsaturated fatty acids (MUFAs), saturated fatty acids (SFAs), and minor components such as sterols and phospholipids. The R. pulmo oocyte lysate exhibited an antibacterial lysozyme-like activity (mean diameter of lysis of 9.33 ± 0.32 mm corresponding to 1.21 mg/mL of hen egg-white lysozyme). The occurrence of defense molecules is a crucial mechanism to grant healthy development of mature eggs and fertilized embryos (and the reproductive success of the species) by preventing marine bacterial overgrowth. As a corollary, these results call for future investigations for an exploitation of R. pulmo biomasses as a resource of bioactive metabolites of biotechnological importance including pharmaceuticals and nutrition.

Modulation of steroidal glycoalkaloid biosynthesis in tomato (Solanum lycopersicum) by jasmonic acid

Jasmonic acid (JA) is a phytohormone involved in plant development and defense. A major role of JA is the enhancement of secondary metabolite production, such as response to herbivory. Systemin is a bioactive plant peptide of 18 amino acids that contributes to the induction of local and systemic defense responses in tomato (Solanum lycopersicum) through JA biosynthesis. The overexpression of systemin (PS-OE) results in constitutive JA accumulation and enhances pest resistance in plants. Conversely, mutant plants affected in linolenic acid synthesis (spr2) are negatively compromised in the production of JA which favors damage and oviposition by insect herbivores. With undirected mass fingerprinting analyses, we found global metabolic differences between genotypes with modified jasmonic acid production. The spr2 mutants were enriched in di-unsaturated fatty acids and generally showed more changes. The PS-OE genotype produced an unidentified compound with a mass-to-charge ratio of 695 (MZ695). Most strikingly, the steroidal glycoalkaloid biosynthesis was negatively affected in the spr2 genotype. Complementation with jasmonic acid could restore the tomatine pathway, which strongly suggests the control of steroidal glycoalkaloid biosynthesis by jasmonic acid. spr2 plants were more susceptible to fungal infection with Fusarium oxysporum f.sp. ciceris, but not to bacterial infection with Clavibacter michiganensis subsp. michiganensis which supports the involvement of steroidal glycoalkaloids in the plant response against fungi.

Age-dependent changes in metabolic profile of turkey spermatozoa as assessed by NMR analysis.

Metabolic profile of fresh turkey spermatozoa at three different reproductive period ages, namely 32, 44 and 56 weeks, was monitored by Nuclear Magnetic Resonance (NMR) spectroscopy and correlated to sperm quality parameters. The age-related decrease in sperm quality as indicated by reduction of sperm concentration, sperm mobility and osmotic tolerance was associated to variation in the level of specific water-soluble and liposoluble metabolites. In particular, the highest levels of isoleucine, phenylalanine, leucine, tyrosine and valine were found at 32 weeks of age, whereas aspartate, lactate, creatine, carnitine, acetylcarnitine levels increased during the ageing. Lipid composition also changed during the ageing: diunsaturated fatty acids level increased from 32 to 56 weeks of age, whereas a reduction of polyunsaturated fatty acids content was observed at 56 weeks. The untargeted approach attempts to give a wider picture of metabolic changes occurring in ageing suggesting that the reduction of sperm quality could be due to a progressive deficiency in mitochondrial energy producing systems, as also prompted by the negative correlation found between sperm mobility and the increase in certain mitochondrial metabolites.

Cercetari privind compozitia chimica si proprietatile reologice ale mixturilor din faina de grau si epicarp de struguri

Grape skin is considered a valuable by-product for antioxidant and antibacterial agent preparation. The grape skin contains some active compounds, such as, dietary fiber, polyphenols, flavonols, and resveratrol; it is commonly used as a nutritional supplement. The main aim of this study was to establish the optimum dose of grape skin flour, to be used as a functional ingredient in the bakery products industry, from both chemical and rheological point of view. The laboratory experiments evaluated the functional potential of wheat flour enriched with grape skin flour, in different proportions, by examining the chemical composition and rheological behaviour of the doughs. Protein, crude fibre, fat, ash and mineral contents were determined. Using �H-NMR spectral technique, the fatty acids composition was determined, especially the concentrations of short-chain saturated fatty acids (C4-C8), di-unsaturated fatty acids, mono-unsaturated fatty acids and long-chain saturated fatty acids (]C8). 1H-NMR spectra were recorded on a Bruker Ascend 400 MHz spectrometer. The rheological behaviour was analyzed using the predefined Chopin + protocol on Mixolab, an equipment of CHOPIN Technologies. Grape skin flour was incorporated into wheat flour at three different levels, 5, 10 and 15% and it was found that incorporation up to a 15% level into the formulation of wheat flour yielded an acceptable product in terms of rheological parameters, with improved chemical, nutritional and functional properties.

The Phospholipid Composition of Kangaroo Spermatozoa Verified by Mass Spectrometric Lipid Analysis.

Cryopreservation of kangaroo sperm has not been successful so far, and yet there is no promising cryopreservation protocol for these cells available. However, conservation of gametes is extremely important, particularly in the context of preserving endangered species. As spermatozoa are comprised of different membrane systems, the composition of these membranes might account for difficulties in cryopreservation. Lipids, as the main components, affect the physical properties of biological membranes and play a major role in sperm maturation. Therefore, knowledge of the lipid composition is crucial for any further step toward the preservation of the species. We used MALDI-TOF, ESI-IT, tandem mass spectrometry, and thin layer chromatography to investigate the lipid composition of epididymal spermatozoa of four different kangaroo species. Spectra of these species were very similar with respect to the identified lipid species. Tremendous changes in the lipid composition during the transit of sperm from caput to cauda epididymis could be seen, specifically an increase in poly-unsaturated fatty acids, ether lipids, and plasmalogens, as well as a reduction in mono- and di-unsaturated fatty acids. Additionally, phosphatidylcholines containing docosatrienoic acid (22:3), a heretofore unknown fatty acid for sperm membranes, showed the highest abundance in kangaroo sperm.

Phytochemical content, Fatty acids composition and antioxidant potential of different pomegranate parts: Comparison between edible and non edible varieties grown in Tunisia

Few comparative studies were interested between edible and non-edible pomegranate varieties. In the present study, flowers, leaves, juice and peel of two pomegranate varieties, ornamental variety “Nana” (NV) and sweet variety “Tounsi” (TV) were compared for their phenolic contents and antioxidant activity. Seeds oils were compared also for their fatty acids (FA) composition.Results showed that peel and juice of NV contained higher content in tannins, Flavonoids and anthocyanins. In contrast, peel and juice of TV were more concentrated in carotenoids and polyphenols. Flowers extracts of TV contained more polyphenols and flavonoids. However leaves from NV provided more polyphenols, flavonoids and anthocyanins. Flowers and leaves proved to be the strongest antioxidants for both varieties. For FA composition, NV was more concentrated in Mono-unsaturated FA (MUFA) however TV contained more Di-unsaturated FA (DiUFA). cis-γ-Linolenic acid was the major FA in NV. Contrariwise punicic acid was the predominant in TV.

Influence of Mg modifier on cis-trans selectivity in partial hydrogenation of biodiesel using different metal types

The catalytic performance of Pd, Pt, and Ni supported on SiO2 catalysts was investigated for partial hydrogenation of soybean methyl esters, in terms of FAME composition and biodiesel properties, especially oxidative stability and cold flow properties. The effect of Mg modifier over SiO2-supported catalysts on cis-trans selectivity of polyunsaturated FAMEs was also examined. The catalytic testing was performed under reaction conditions of 4bar hydrogen pressure and 80–120°C. Hydrogenation activity was presented by turnover frequency (TOF) of diunsaturated fatty acid (C18:2) within 4h of the reaction time. The highest TOF was obtained over Pd catalysts, while the lowest TOF was obtained from Ni catalysts. At high reaction temperature conditions showed a large amount of cis-monounsaturated fatty acid (cis-C18:1); however, it exhibited a large amount of trans-monounsaturated fatty acid (trans-C18:1) which has a negative impact on biodiesel properties. The XPS revealed that the introduction of Mg leads to a strong metal–support interaction caused by electron transfer from the support to the metal, which decreased trans-C18:1 formation and presented the higher oxidative stability than the catalysts without Mg modifier.

Oxidative Stability of Commodity Fats and Oils: Modeling Based on Fatty Acid Composition

AbstractAlthough fatty acid (FA) composition is known to be of fundamental importance to oxidative stability in lipids, consistent quantifications of the magnitude of this association have proved elusive. The objective of this study was to quantify the relationship between FA composition and stability on a large scale within comparable lipid systems, with the numerical effects of individual outcome factors (e.g. output of a singular assay, oxidative products after a brief period of time, etc.) attenuated by incorporation into a comprehensive summation of stability. The stability of 50 plant‐based oils and fats was modeled according to FA composition, utilizing a quantification of stability that encompassed the complete oxidation curves of four distinct classical assays (two 1° and two 2° oxidation assessments) throughout 2 months of accelerated storage (60 °C). In our models, the concentrations of monounsaturated FA (MUFA), diunsaturated FA (DiUFA), and triunsaturated FA (TriUFA) together demonstrated a very strong correlation with our consolidated measure of stability (r2 = 0.915; greater than observed with our assessments by individual assays). The resultant model also indicated the relative effect upon magnitude of oxidation of MUFA:DiUFA:TriUFA to be approximately 1:3:12—substantially greater than the 1:2:3 ratio of their relative unsaturation.