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Molecules (Basel, Switzerland) Jun 2021In this paper, we have performed the Lipozyme 435-catalyzed synthesis of xylose oleate in methyl ethyl ketone (MEK) from xylose and oleic acid. The effects of...
In this paper, we have performed the Lipozyme 435-catalyzed synthesis of xylose oleate in methyl ethyl ketone (MEK) from xylose and oleic acid. The effects of substrates' molar ratios, reaction temperature, reaction time on esterification rates, and Lipozyme 435 reuse were studied. Results showed that an excess of oleic acid (xylose: oleic acid molar ratio of 1:5) significantly favored the reaction, yielding 98% of xylose conversion and 31% oleic acid conversion after 24 h-reaction (mainly to xylose mono- and dioleate, as confirmed by mass spectrometry). The highest Lipozyme 435 activities occurred between 55 and 70 °C. The predicted Ping Pong Bi Bi kinetic model fitted very well to the experimental data and there was no evidence of inhibitions in the range assessed. The reaction product was purified and presented an emulsion capacity close to that of a commercial sugar ester detergent. Finally, the repeated use of Lipozyme 435 showed a reduction in the reaction yields (by 48 and 19% in the xylose and oleic acid conversions, respectively), after ten 12 h-cycles.
Topics: Biocatalysis; Butanones; Esterification; Hot Temperature; Lipase; Oleic Acid; Xylose
PubMed: 34205848
DOI: 10.3390/molecules26113317 -
Molecules (Basel, Switzerland) Jul 2020Microbial conversion of oleic acid () to form value-added industrial products has gained increasing scientific and economic interest. So far, the production of natural...
Microbial conversion of oleic acid () to form value-added industrial products has gained increasing scientific and economic interest. So far, the production of natural lactones with flavor and fragrance properties from fatty acids by non-genetically modified organisms (non-GMO) involves whole cells of bacteria catalyzing the hydration of unsaturated fatty acids as well as yeast strains responsible for further β-oxidation processes. Development of a non-GMO process, involving a sole strain possessing both enzymatic activities, significantly lowers the costs of the process and constitutes a better method from the customers' point of view regarding biosafety issues. Twenty bacteria from the genus of , , , , , , and were screened for oxidative functionalization of oleic acid (). PCM525 was selected as the sole strain catalyzing the one-pot transformation of oleic acid () into natural valuable peach and strawberry-flavored γ-dodecalactone () used in the food, beverage, cosmetics and pharmaceutical industries. Based on the identified products formed during the process of biotransformation, we clearly established a pathway showing that oleic acid () is hydrated to 10-hydroxystearic acid (), then oxidized to 10-ketostearic acid (), giving 4-ketolauric acid () after three cycles of β-oxidation, which is subsequently reduced and cyclized to γ-dodecalactone () (Scheme 1). Moreover, three other strains ( DSM44534, PCM2166, sp. DSM44016), with high concomitant activities of oleate hydratase and alcohol dehydrogenase, were identified as efficient producers of 10-ketostearic acid (), which can be used in lubricant and detergent formulations. Considering the prevalence of γ-dodecalactone () and 10-ketostearic acid () applications and the economic benefits of sustainable management, microbial bioconversion of oleic acid () is an undeniably attractive approach.
Topics: 4-Butyrolactone; Carbon; Culture Media; Gas Chromatography-Mass Spectrometry; Industrial Microbiology; Linoleic Acid; Micrococcus luteus; Oleic Acid; Oxidation-Reduction; Stearic Acids; Surface-Active Agents; alpha-Linolenic Acid
PubMed: 32630666
DOI: 10.3390/molecules25133024 -
Arteriosclerosis, Thrombosis, and... Dec 2020Compare the postprandial fatty acid metabolism of isotopically labeled stearate (U-C18:0) and oleate (U-C18:1). Approach and Results: In conjunction with a... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
Compare the postprandial fatty acid metabolism of isotopically labeled stearate (U-C18:0) and oleate (U-C18:1). Approach and Results: In conjunction with a randomized-controlled crossover trial, 6 hypercholesterolemic postmenopausal women (≥50 years; body mass index: 25.6±3.0 kg/m; LDL [low-density lipoprotein]-cholesterol ≥110 mg/dL) consumed isocaloric diets enriched in 18:0 or 18:1 (10%-15% E) for 5 weeks each. On day 1 of week 5, following a 12-hour fast, participants receive their experimental diet divided into 13 hourly meals beginning at 8 am. U-C18:0 or U-C18:1 was incorporated into the 1:00 pm meal (1.0 mg/kg body weight). Serial blood and breath samples were collected over 12 hours and fasting samples at 24 and 48 hours. Plasma and lipid subfraction fatty acid profiles were assessed by gas chromatography-flame ionization detector, isotope-enrichment by liquid chromatography time-of-flight mass spectrometry, and fatty acid oxidation rate (expired CO) by isotope ratio mass spectrometry. Both diets resulted in similar plasma LDL-cholesterol concentrations. Kinetic curves showed that U-C18:0 had a higher plasma area under the curve (66%), lower plasma clearance rate (-46%), and a lower cumulative oxidation rate (-34%) than U-C18:1. Three labeled plasma metabolites of U-C18:0 were detected: C16:0, C16:1, and C18:1. No plasma metabolites of U-C18:1 were detected within the study time-frame. Higher incorporation of 18:0 in cholesteryl ester and triglyceride fractions was observed on the 18:0 compared with the 18:1 diet.
CONCLUSIONS
The neutrality of 18:0 on plasma LDL-cholesterol concentrations is not attributable to a single factor. Compared with 18:1, 18:0 had higher plasma area under the curve because of lower clearance and oxidation rates, underwent both a direct and a multistage conversion to 18:1, and was preferentially incorporated into cholesteryl esters and triglycerides.
Topics: Aged; Aged, 80 and over; Carbon Isotopes; Cholesterol Esters; Cholesterol, LDL; Cross-Over Studies; Female; Gastrointestinal Absorption; Humans; Hypercholesterolemia; Middle Aged; Oleic Acid; Oxidation-Reduction; Postmenopause; Postprandial Period; Stearic Acids; Triglycerides
PubMed: 32998517
DOI: 10.1161/ATVBAHA.120.315260 -
Lipids in Health and Disease May 2019Since oleic acid (OA, 18:1 c9) and arachidonic acid (AA, 20:4 n6) may have antagonistic actions, it is of interest to assess their relative abundances. We previously...
BACKGROUND
Since oleic acid (OA, 18:1 c9) and arachidonic acid (AA, 20:4 n6) may have antagonistic actions, it is of interest to assess their relative abundances. We previously reported an inverse correlation between % OA and %AA. However, percentages of the same sum may be correlated without involving biology. We now investigate whether random numbers, generated within the true concentration distributions for OA and AA, may be correlated.
METHODS
We reanalysed data from a previous diet trial in chickens. Breast muscle was collected, and the concentration of fatty acids in muscle lipids was determined using gas chromatography. We computed R = S - OA - AA, where S is the sum of all fatty acids (g/kg) and R is concentration of all fatty acids, except OA and AA. From histograms we found physiological distributions of OA, AA and R. Then we generated random numbers for each of 3 variables (n = 163), within the distributions (g/kg) for OA (1-7), AA (0.25-0.39), and R (4-10). Next we made scatterplots of % OA vs. % AA, and studied how a narrowing or broadening of distributions might change the relationship.
RESULTS
Also with random numbers, generated within true concentration distributions for OA and AA, we found an inverse relationship between their percentages (r = - 0.356, p < 0.001; r = 163); however, the points were not close to the regression line. The %OA vs. %AA relationship changed appreciably in response to slightly altering concentration distributions of OA and AA, and a negative association could be changed to become positive.
CONCLUSION
Using random numbers, generated within the biological distributions for OA, AA, and sum of the remaining fatty acids, we found an inverse relationship between "% OA" and "% AA", but the scatterplot was poor compared with that obtained with real values. The association between relative abundances of random numbers of OA and AA was very sensitive to changes in distributions, and a negative association could be changed to become positive by slightly altering the distributions. Thus, the association between relative abundances of OA and AA could be partly caused by the particular distribution of the fatty acid concentration: a Distribution Dependent Correlation.
Topics: Animals; Arachidonic Acid; Chickens; Fatty Acids; Muscles; Oleic Acid
PubMed: 31138212
DOI: 10.1186/s12944-019-1067-7 -
Journal of Neurochemistry Aug 1997The role of oleic acid in the modulation of gap junction permeability was studied in cultured rat astrocytes by the scrape-loading/Lucifer yellow transfer technique....
The role of oleic acid in the modulation of gap junction permeability was studied in cultured rat astrocytes by the scrape-loading/Lucifer yellow transfer technique. Incubation with oleic acid caused a dose-dependent inhibition of gap junction permeability by 79.5% at 50 microM, and no further inhibition was observed by increasing the oleic acid concentration to 100 microM. The oleic acid-mediated inhibition of gap junction permeability was reversible and was prevented by bovine serum albumin. The potency of oleic acid-related compounds in inhibiting gap junction permeability was arachidonic acid > oleic acid > oleyl alcohol > palmitoleic acid > stearic acid > octanol > caprylic acid > palmitic acid > methyloleyl ester. Oleic acid and arachidonic acid, but not methyloleyl ester, increased glucose uptake by astrocytes. Neither oleic acid nor arachidonic acid increased glucose uptake in the poorly coupled glioma C6 cells. These results support that the inhibition of gap junction permeability is associated with the increase in glucose uptake. We suggest that oleic acid may be a physiological mediator of the transduction pathway leading to the inhibition of intercellular communication.
Topics: Animals; Astrocytes; Cell Membrane Permeability; Cells, Cultured; Deoxyglucose; Fluorescent Dyes; Gap Junctions; Glucose; Isoquinolines; Oleic Acid; Rats; Rats, Wistar; Serum Albumin, Bovine
PubMed: 9231732
DOI: 10.1046/j.1471-4159.1997.69020721.x -
American Journal of Physiology.... Mar 2015Health concerns have led to recommendations to replace saturated fats with unsaturated fats. However, addition of unsaturated fatty acids may lead to changes in the way... (Clinical Trial)
Clinical Trial
Health concerns have led to recommendations to replace saturated fats with unsaturated fats. However, addition of unsaturated fatty acids may lead to changes in the way foods are perceived in the oral cavity. This study tested the taste sensitivity to and emulsion characteristics of oleic, linoleic, and α-linolenic acids. The hypothesis tested was that oral sensitivity to nonesterified fatty acids would increase with degree of unsaturation but that in vitro viscosities and particle sizes of these emulsions would not differ. Oral taste thresholds were obtained using the three-alternative, forced-choice, ascending method. Each participant was tested on each fat 7 times, for a total of 21 study visits, to account for learning effects. Viscosities were obtained for the blank solutions and all three emulsions. Results indicate lower oral thresholds to linoleic and α-linolenic than oleic acid. At higher shear rates, 5% oleic and linoleic acid were more viscous than other samples. More-dilute emulsions showed no significant differences in viscosity. Particle sizes of the emulsions increased very slightly with increasing unsaturation. Together, the emulsion characteristics and oral sensitivity data support a taste mechanism for nonesterified fatty acid detection.
Topics: Adolescent; Adult; Cross-Over Studies; Emulsions; Female; Humans; Linoleic Acid; Male; Middle Aged; Mouth Mucosa; Oleic Acid; Random Allocation; Sensory Thresholds; Taste; alpha-Linolenic Acid
PubMed: 25540234
DOI: 10.1152/ajpgi.00394.2014 -
Journal of Oleo Science Jun 2018Most natural lipids contain a complex mixture of individual triacylglycerols (TAGs). An in-depth knowledge of the mixing behavior of TAGs is necessary for the rational... (Review)
Review
Most natural lipids contain a complex mixture of individual triacylglycerols (TAGs). An in-depth knowledge of the mixing behavior of TAGs is necessary for the rational design and engineering of food materials. The binary phase diagram of TAGs is a simplified model that can be explored to help foster an understanding of the phase behavior of complex fats and oils. This article reviews recent research on the binary phase behavior of saturated-unsaturated mixed-acid TAGs, with special emphasis on the stearicunsaturated and palmitic-unsaturated diacid TAGs. The occurrence of polymorphic forms and mutual solubility of TAG mixtures are strongly related to the glycerol conformation of the saturated-oleic diacid TAGs; it appears to be most influenced by the chain-length mismatch in saturated-elaidic diacid TAGs. In addition, the polymorphism of pure enantiomers and racemic mixture of chiral TAGs was also reviewed, while the effect of chirality on mixing behavior was discussed.
Topics: Fatty Acids, Unsaturated; Food; Oleic Acid; Oleic Acids; Palmitic Acid; Phase Transition; Stearic Acids; Triglycerides
PubMed: 29760333
DOI: 10.5650/jos.ess17263 -
Journal of Oleo Science 2024Unsaturated fatty acids, such as oleic and linoleic acids, are easily oxidized by exposure to temperature and light in the presence of air to form unsaturated fatty acid... (Comparative Study)
Comparative Study
Unsaturated fatty acids, such as oleic and linoleic acids, are easily oxidized by exposure to temperature and light in the presence of air to form unsaturated fatty acid hydroperoxides as primary oxidation products. However, the catabolic rates of unsaturated fatty acid hydroperoxides in the human body remain unknown. In this study, ethyl esters of C-labeled linoleic acid (*C18:2-EE) and oleic acid (*C18:1-EE) and their hydroperoxides (*C18:2-EE-OOH and *C18:1-EE-OOH, respectively) prepared by the photo-oxidation of *C18:2-EE and *C18:1-EE, respectively, were administered to mice and their catabolic rates were determined by measuring the expired CO levels. *C18:2-EE-OOH and *C18:1-EE-OOH were β-oxidized faster than *C18:2-EE and *C18:1-EE, respectively. Notably, rapid β-oxidation of *C18:2-EE-OOH and *C18:1-EE-OOH was similar to that of medium-chain fatty acids, such as octanoic acid. Then, degradation products of C18:2-EE-OOH and C18:1-EE-OOH were analyzed under gastric conditions by gas chromatography/mass spectrometry. Major decomposition products of C18:2-EE-OOH and C18:1-EE-OOH were medium-chain compounds, such as octanoic acid ethyl ester, 9-oxo-nonanoic acid ethyl ester, and 10-oxo-8-decenoic acid ethyl esters, indicating that C18:2-EE-OOH and C18:1-EE-OOH isomers formed during photo-oxidation were decomposed under acidic conditions. These findings support previous reports that dietary lipid hydroperoxides are not absorbed into the intestine as lipid hydroperoxides but as degradation products. This is the first study to suggest that dietary lipid hydroperoxides decompose during gastric digestion to form medium-chain compounds that are directly absorbed into the liver via the portal vein and rapidly catabolized via β-oxidation.
Topics: Animals; Oxidation-Reduction; Oleic Acid; Linoleic Acid; Carbon Dioxide; Carbon Isotopes; Mice; Male; Hydrogen Peroxide
PubMed: 38825538
DOI: 10.5650/jos.ess23236 -
Oleic acid uptake and binding by rat adipocytes define dual pathways for cellular fatty acid uptake.Journal of Lipid Research Apr 2001Oleic acid (OA) uptake by rat adipocytes and the proportions of intracellular unesterified [3H]OA and its 3H-labeled esters were determined over 300 s. Uptake was linear...
Oleic acid (OA) uptake by rat adipocytes and the proportions of intracellular unesterified [3H]OA and its 3H-labeled esters were determined over 300 s. Uptake was linear for 20;-30 s, with rapid esterification indicating entry into normal metabolic pathways. Initial rates of OA uptake and its binding to plasma membranes were studied over a spectrum of oleic acid:bovine serum albumin (BSA) ratios, and expressed as functions of unbound OA concentrations calculated with both the 1971 OA:BSA association constants of Spector, Fletcher, and Ashbrook and more recent constants (e.g., the 1993 constants of Richieri, Anel, and Kleinfeld), which generate concentrations 10- to 100-fold lower. In either case, uptake was the sum of saturable and linear processes, with > or =90% occurring via the saturable pathway when the OA:BSA molar ratio was within the physiologic range (0.5;-3.0). Within this range, rate constants for saturable transmembrane influx (k(s)), calculated from both sets of constants, were similar (2.9 s(-1)) and were 10- to 30-fold faster than those for nonsaturable uptake (k(ns) = 0.26;-0.10 s(-1), t1/2 = 2.7;-6.6 s, based on the constants of Spector et al. and Richieri et al., respectively). The rate of oleic acid flip-flop into rat adipocytes (k(ff) = 0.16 +/- 0.02 s(-1), t1/2 = 4.3 +/- 0.5 s), computed from published data, was similar to k(ns). Thus, OA uptake occurs by both a saturable mechanism and passive flip-flop. This conclusion is independent of the OA:BSA association constants used to analyze the experimental measurements.
Topics: Adipocytes; Animals; Biological Transport; Cell Membrane; Humans; Kinetics; Male; Oleic Acid; Rats; Rats, Sprague-Dawley; Time Factors
PubMed: 11290822
DOI: No ID Found -
Cells Feb 2022The maintenance of cellular homeostasis over time is essential to avoid the degeneration of biological systems leading to aging and disease. Several interconnected...
The maintenance of cellular homeostasis over time is essential to avoid the degeneration of biological systems leading to aging and disease. Several interconnected pathways are active in this kind of quality control. One of them is autophagy, the vacuolar degradation of cellular components. The absence of the sorting nexin PaATG24 (SNX4 in other organisms) has been demonstrated to result in impairments in different types of autophagy and lead to a shortened lifespan. In addition, the growth rate and the size of vacuoles are strongly reduced. Here, we report how an oleic acid diet leads to longevity of the wild type and a deletion mutant (). The lifespan extension is linked to altered membrane trafficking, which abrogates the observed autophagy defects in by restoring vacuole size and the proper localization of SNARE protein PaSNC1. In addition, an oleic acid diet leads to an altered use of the mitochondrial respiratory chain: complex I and II are bypassed, leading to reduced reactive oxygen species (ROS) production. Overall, our study uncovers multiple effects of an oleic acid diet, which extends the lifespan of and provides perspectives to explain the positive nutritional effects on human aging.
Topics: Autophagy; Energy Metabolism; Humans; Longevity; Mitochondria; Oleic Acid; Podospora
PubMed: 35159328
DOI: 10.3390/cells11030519