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Genes Feb 2022The ω-3 fatty acid desaturase () gene encodes a rate-limiting enzyme in the synthesis of α-linolenic acid. In this study, homologous cloning was used to obtain the...
The ω-3 fatty acid desaturase () gene encodes a rate-limiting enzyme in the synthesis of α-linolenic acid. In this study, homologous cloning was used to obtain the full-length sequence of the gene of . The full-length DNA sequence was 1871 bp long, with 8 exons and 7 introns. The structural analysis of the amino acid sequence revealed that the PvFAD3 protein contained three histidine-conserved regions and an endoplasmic reticulum retention signal. The real-time reverse transcription-polymerase chain reaction performed for determining the expression patterns of the gene in different tissues of showed that expression was highly expressed in the fast oil accumulation stage of seed. The analysis of subcellular localization assay in epidermal cells of tobacco () leaves showed that the PvFAD3 protein was mainly localized in the endoplasmic reticulum. Seed-specific overexpression vectors were constructed, and -mediated genetic transformation was performed to obtain transgenic tobacco plants overexpressing . The results of fatty acid assays performed using harvested seeds showed a significant increase in α-linolenic acid content, a dramatic decrease in linoleic acid content, and an obvious increase in oil content in transgenic tobacco seeds. Collectively, the gene of was confirmed as a key enzyme gene for α-linolenic acid synthesis; thus, indicating that the gene can be used for fatty acid fraction improvement in oilseed plants.
Topics: Euphorbiaceae; Fatty Acids; Plants, Genetically Modified; Seeds; Nicotiana; alpha-Linolenic Acid
PubMed: 35328004
DOI: 10.3390/genes13030450 -
European Journal of Clinical Nutrition Feb 2000To collect (i) baseline data and (ii) execute a large multicentre study examining the effect of trans alpha-linolenic acid on its incorporation into plasma lipids and on... (Clinical Trial)
Clinical Trial Randomized Controlled Trial
OBJECTIVE
To collect (i) baseline data and (ii) execute a large multicentre study examining the effect of trans alpha-linolenic acid on its incorporation into plasma lipids and on risk factors for coronary heart disease.
DESIGN
Male volunteers were recruited and the habitual diet assessed by a 4-d weighed record. Fatty acid composition of plasma and platelet lipids were determined by gas chromatography at baseline. After a 6 week run-in period on a trans 'free' diet, male volunteers were randomised to consume 0.6 % of energy trans alpha-linolenic acid or to continue with a diet 'low' in trans alpha-linolenic acid for 6 weeks.
SETTING
Three European university research departments supported by the research and development departments of the food industry.
SUBJECTS
Male volunteers (88) recruited by local advertisement.
METHODS
Replacement of 30 % of the fat of the habitual diet by margarine, oil and foods. Rapeseed oil was deodorised especially to produce the trans 'free' and 'high' trans foods for this study. The incorporation and conversion of trans alpha-linolenic acid into plasma lipids and platelets was assessed by gas chromatography and dietary compliance was verified by 4-d weighed record.
RESULTS
Less trans alpha-linolenic acid isomers are incorporated into human plasma lipids in French volunteers than in Dutch or Scottish volunteers consuming their habitual diets. Trans 'free' alpha-linolenic acid-rich oil can be produced by careful deodorization during refining. The 'high' trans diet provided 1410+/-42 mg/d trans isomers of alpha-linolenic acid, whilst the 'low' trans group consumed 60+/-75 mg/d. The change in plasma lipid and platelet fatty acid composition documented that trans linolenic isomers are incorporated and converted to a trans isomer of eicosapentaenoic acid. Only the 15-trans alpha-linolenic acid is incorporated into plasma cholesteryl esters. The group consuming low trans diet had a slightly higher intake of fat, especially saturated and monounsaturated fat.
CONCLUSIONS
Trans 'free' rapeseed oil, rich in alpha-linolenic acid, can be produced by careful deodorization. Dietary records show good compliance. Dietary trans isomers of alpha-linolenic acid are incorporated in plasma lipids and converted to long-chain polyunsaturated fatty acids. Their effects on risk factors for coronary heart disease and their metabolism will be reported elsewhere.
SPONSORSHIP
European Commission (FAIR 95-0594 grant). European Journal of Clinical Nutrition (2000) 54, 104-113
Topics: Adult; Blood Platelets; Chromatography, Gas; Coronary Disease; Dietary Fats, Unsaturated; Energy Intake; Fatty Acids; Fatty Acids, Monounsaturated; France; Humans; Isomerism; Lipids; Male; Netherlands; Rapeseed Oil; Risk Factors; Scotland; alpha-Linolenic Acid
PubMed: 10694780
DOI: 10.1038/sj.ejcn.1600903 -
Journal of Chromatography. B,... Sep 2020Conjugated linoleic and linolenic acids (CLA and CLnA) can be found in dairy, ruminant meat and oilseeds, these types of unsaturated fatty acids consist of various... (Review)
Review
Conjugated linoleic and linolenic acids (CLA and CLnA) can be found in dairy, ruminant meat and oilseeds, these types of unsaturated fatty acids consist of various positional and geometrical isomers, and have demonstrated health-promoting potential for human beings. Extensive reviews have reported the physiological effects of CLA, CLnA, while little is known regarding their isomer-specific effects. However, the isomers are difficult to identify, owing to (i) the similar retention time in common chromatographic methods; and (ii) the isomers are highly sensitive to high temperature, pH changes, and oxidation. The uncertainties in molecular structure have hindered investigations on the physiological effects of CLA and CLnA. Therefore, this review presents a summary of the currently available technologies for the structural determination of CLA and CLnA, including the presence confirmation, double bond position determination, and the potential stereo-isomer determination. Special focus has been projected to the novel techniques for structure determination of CLA and CLnA. Some possible future directions are also proposed.
Topics: Animals; Chromatography, Liquid; Linoleic Acids, Conjugated; Mass Spectrometry; Milk; Models, Molecular; Molecular Conformation; alpha-Linolenic Acid
PubMed: 32755819
DOI: 10.1016/j.jchromb.2020.122292 -
Food Chemistry Dec 2017An α-linolenic acid (ALA)-rich triacylglycerol (TAG) was synthesized from an ALA-rich fatty acid (FA) from perilla oil and glycerol, using a newly prepared immobilized...
An α-linolenic acid (ALA)-rich triacylglycerol (TAG) was synthesized from an ALA-rich fatty acid (FA) from perilla oil and glycerol, using a newly prepared immobilized lipase under vacuum. The ALA-rich FA (purity >90wt%) used as the substrate was prepared by urea complexation from perilla oil FAs. Liquid Lipozyme TL 100L lipase from Thermomyces lanuginosus was used for immobilization. Nine different hydrophilic and hydrophobic carriers for immobilization were tested, and Duolite A568, which is a hydrophilic resin, was selected as the best carrier. This immobilized lipase was used to synthesize TAG by direct esterification under vacuum. The parameters investigated were temperature, enzyme loading, and vacuum level. The optimum reaction conditions were a temperature of 60°C, an enzyme loading of 15% (based on the total weight of the substrate), and a vacuum of 0.7kPa, respectively. The maximum conversion to TAG of ca. 88wt% was obtained in 12h under the optimum conditions.
Topics: Ascomycota; Enzymes, Immobilized; Esterification; Lipase; Triglycerides; alpha-Linolenic Acid
PubMed: 28764049
DOI: 10.1016/j.foodchem.2017.05.161 -
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 -
Molecular Nutrition & Food Research Jan 2022The proliferation and differentiation of intestinal stem cells (ISCs) are the basis of intestinal renewal and regeneration, and gut microbiota plays an important role in...
SCOPE
The proliferation and differentiation of intestinal stem cells (ISCs) are the basis of intestinal renewal and regeneration, and gut microbiota plays an important role in it. Dietary nutrition has the effect of regulating the activity of ISCs; however, the regulation effect of α-linolenic acid (ALA) has seldom been reported.
METHODS AND RESULTS
After intervening mice with different doses of ALA for 30 days, it is found that ALA (0.5 g kg ) promotes small intestinal and villus growth by activating the Wnt/β-catenin signaling pathway to stimulate the proliferation of ISCs. Furthermore, ALA administration increases the abundance of the Ruminococcaceae and Prevotellaceae, and promotes the production of short-chain fatty acids (SCFAs). Subsequent fecal transplantation and antibiotic experiments demonstrate that ALA on the proliferation of ISCs are gut microbiota dependent, among them, the functional microorganism may be derived from Ruminococcaceae. Administration of isobutyrate shows a similar effect to ALA in terms of promoting ISCs proliferation. Furthermore, ALA mitigates 5-fluorouracil-induced intestinal mucosal damage by promoting ISCs proliferation.
CONCLUSION
These results indicate that SCFAs produced by Ruminococcaceae mediate ALA promote ISCs proliferation by activating the Wnt/β-catenin signaling pathway, and suggest the possibility of ALA as a prebiotic agent for the prevention and treatment of intestinal mucositis.
Topics: Animals; Cell Proliferation; Fatty Acids, Volatile; Intestinal Mucosa; Intestines; Mice; Stem Cells; alpha-Linolenic Acid
PubMed: 34708542
DOI: 10.1002/mnfr.202100408 -
The American Journal of Clinical... Jul 2014α-Linolenic acid (ALA) is an n-3 (ω-3) fatty acid found mostly in plant foods such as flaxseed, walnuts, and vegetable oils, including canola and soybean oils. Most of...
α-Linolenic acid (ALA) is an n-3 (ω-3) fatty acid found mostly in plant foods such as flaxseed, walnuts, and vegetable oils, including canola and soybean oils. Most of the health benefits observed for n-3 fatty acids have been attributed to the marine-derived long-chain n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid, because of the strength of evidence from both epidemiologic studies and randomized controlled trials. Furthermore, the observed cardioprotective and other health effects of ALA have been credited to its precursor role in converting to EPA in the body. The promotion of fatty fish consumption for its documented health benefits may not be practical for those who are concerned with the unsustainability of marine sources or who avoid eating fish for a variety of reasons. ALA-rich plant sources are more abundant and may serve as a suitable alternate. It is therefore worthwhile to consider the evidence for the health benefits of ALA. The purpose of this review is to present the evidence from recent studies on the association between ALA and cardiovascular disease, type 2 diabetes, and fracture risk. The potential mechanisms that explain these associations will also be briefly discussed.
Topics: Cardiovascular Diseases; Diabetes Mellitus, Type 2; Diet; Dietary Fats; Fractures, Bone; Health; Humans; Plant Oils; alpha-Linolenic Acid
PubMed: 24898228
DOI: 10.3945/ajcn.113.071514 -
Biochimica Et Biophysica Acta Sep 1994Cholesterol is demonstrated to condense phosphatidylcholine (PC) monolayers and bilayers containing stearic acid in the sn-1 position and alpha-linolenic acid in the... (Comparative Study)
Comparative Study
Cholesterol is demonstrated to condense phosphatidylcholine (PC) monolayers and bilayers containing stearic acid in the sn-1 position and alpha-linolenic acid in the sn-2 position (18:0, alpha-18:3 PC) but has no effect when gamma-linolenic acid occupies the sn-2 position (18:0,gamma-18:3 PC). Cholesterol-induced condensation is measured by area/molecule determinations made on monolayers using a Langmuir trough, while condensation in bilayers is followed by the fluorescent dyes merocyanine (MC540) and dansyllysine. Permeability to erythritol is also demonstrated to be diminished by cholesterol for the condensable 18:0,alpha-18:3 PC bilayer membranes but not the 18:0,gamma-18:3 PC membranes. alpha- and gamma-linolenic acid are isomers containing 18 carbons and three unsaturations. Both fatty acids have unsaturations at positions 9 and 12 and differ only in the location of the third unsaturation, at either position 6 for gamma-linolenic acid (an omega-6 fatty acid) and at position 15 for alpha-linolenic acid (an omega-3 fatty acid). Here lipid-cholesterol interaction is used to distinguish the effect of position of unsaturation on membrane structure.
Topics: Cholesterol; Isomerism; Lipid Bilayers; Phosphatidylcholines; alpha-Linolenic Acid; gamma-Linolenic Acid
PubMed: 7918592
DOI: 10.1016/0005-2760(94)90036-1 -
Circulation Jul 2008Intake of long-chain n-3 fatty acids found in fish is low in many countries worldwide. alpha-Linolenic acid could be a viable cardioprotective alternative to these fatty...
BACKGROUND
Intake of long-chain n-3 fatty acids found in fish is low in many countries worldwide. alpha-Linolenic acid could be a viable cardioprotective alternative to these fatty acids in these countries.
METHODS AND RESULTS
Cases (n=1819) with a first nonfatal acute myocardial infarction and population-based controls (n=1819) living in Costa Rica matched for age, sex, and area of residence were studied. Fatty acids were assessed by gas chromatography in adipose tissue samples and by a validated food frequency questionnaire specifically designed for this population. Odds ratios and 95% confidence intervals were calculated from multivariate conditional logistic regression models. alpha-Linolenic acid in adipose tissue ranged from 0.36% in the lowest decile to 1.04% in the highest decile. The corresponding median levels of intake were 0.42% and 0.86% energy. Greater alpha-linolenic acid (assessed either in adipose or by questionnaire) was associated with lower risk of myocardial infarction. The odds ratios for nonfatal myocardial infarction for the highest compared with the lowest deciles were 0.41 (95% confidence interval, 0.25 to 0.67) for alpha-linolenic acid in adipose tissue and 0.61 (95% confidence interval, 0.42 to 0.88) for dietary alpha-linolenic acid. The relationship between alpha-linolenic acid and myocardial infarction was nonlinear; risk did not decrease with intakes > approximately 0.65% energy (1.79 g/d). Fish or eicosapentaenoic acid and docosahexaenoic acid intake at the levels found in this population did not modify the observed association.
CONCLUSIONS
Consumption of vegetable oils rich in alpha-linolenic acid could confer important cardiovascular protection. The apparent protective effect of alpha-linolenic acid is most evident among subjects with low intakes.
Topics: Adipose Tissue; Aged; Chromatography, Gas; Costa Rica; Fatty Acids; Female; Humans; Male; Middle Aged; Myocardial Infarction; Plant Oils; Risk; alpha-Linolenic Acid
PubMed: 18606916
DOI: 10.1161/CIRCULATIONAHA.107.762419 -
Journal of Separation Science Jul 2019α-Linolenic acid is an essential omega-3 fatty acid needed for human health. However, the isolation of high-purity α-linolenic acid from plant resources is...
α-Linolenic acid is an essential omega-3 fatty acid needed for human health. However, the isolation of high-purity α-linolenic acid from plant resources is challenging. The preparative separation methods of α-linolenic acid by both conventional and pH-zone refining counter current chromatography were firstly established in this work. The successful separation of α-linolenic acid by conventional counter current chromatography was achieved by the optimized solvent system n-heptane/methanol/ water/acetic acid (10:9:1:0.04, v/v), producing 466 mg of 98.98% α-linolenic acid from 900 mg free fatty acid sample prepared from perilla seed oil with linoleic acid and oleic acid as by-products. The scaled-up separation in 45× is efficient without loss of resolution and extension of separation time. The separation of α-linolenic acid by pH-zone refining counter current chromatography was also satisfactory by the solvent system n-hexane/methanol/water (10:5:5, v/v) and the optimized concentration of trifluoroacetic acid 30 mM and NH OH 10 mM. The separation can be scaled up in 180× producing 9676.7 mg of 92.79% α-linolenic acid from 18 000 mg free fatty acid sample. pH-zone refining counter current chromatography exhibits a great advantage over conventional counter current chromatography with 20× sample loading capacity on the same column.
Topics: Countercurrent Distribution; Hydrogen-Ion Concentration; Plant Extracts; Plant Oils; alpha-Linolenic Acid
PubMed: 31066188
DOI: 10.1002/jssc.201900189