Fatty Acid Chain Length Research Articles

Measurement of Fatty Acid Oxidation by High-Resolution Respirometry: Special Considerations for Analysis of Skeletal and Cardiac Muscle and Adipose Tissue.

High-resolution respirometry is a state-of-the-art approach for the quantitation of mitochondrial function. Isolated mitochondria, cultured cells, or tissues/fibers are suspended in oxygenated respiration medium within a closed chamber and substrates or inhibitors added in a stepwise manner. The dissolved oxygen concentration decreases as aerobic metabolism in the specimen proceeds, recorded by an oxygen sensor within the chamber to give a quantifiable measure of oxygen consumption by the sample. Measuring oxygen consumption using a variety of respiratory substrates or respiratory complex-targeted inhibitors enables multiple respiratory pathways to be interrogated to determine the functional capacity of the mitochondria in real time. Using a substrate-uncoupler-inhibitor titration (SUIT) protocol, we have developed a method which makes use of differing chain length fatty acids to derive a measure of fatty acid-stimulated respiration through β-oxidation in a variety of tissue types including skeletal and cardiac muscles and brown and white adipose tissues. This report provides technical details of the protocol, and the adaptations employed, to generate robust analysis of mitochondrial fatty acid β-oxidation.

Distribution of Domains Formed by Lateral Packing of Intercellular Lipid in the Stratum Corneum.

Intercellular lipids fill the interstices of corneocytes and serve a barrier function. The amount of transdermal water evaporation varies depending on the packing structure of intercellular lipids, as this structure is important for maintaining barrier efficacy. This packing structure consists of a mixture of crystals (orthorhombic and hexagonal) and liquid crystals (fluid phase), and the proportion of these phases is thought to affect barrier function. However, there have been no methods to visualize the actual distribution of the domains formed by packing structure in intercellular lipids. In this study, the planar distribution of intercellular lipid structures was determined using focal plane array (FPA)-based Fourier transform (FT) IR imaging analysis of stratum corneum cell units obtained by grid stripping. The lipid composition of ceramides was revealed by electrospray ionization tandem mass spectrometry (ESI-MS/MS)-based shotgun lipidomics. The distribution of domains formed by packing structures and the lipid composition of ceramides was compared in skin with high- or low-transepidermal water loss (TEWL). The orthorhombic proportion was lower in high-TEWL skin than in low-TEWL skin. ESI-MS/MS-based shotgun lipidomics analysis showed that the alpha-hydroxyceramide content in the low- and high-TEWL groups differed regarding the distribution of fatty acid chain lengths. The evaluation of stratum corneum cell units using FPA-based FTIR imaging is an innovative technology that can visualize the distribution of domains formed by intercellular lipid-packing structures. Increased proportions of alpha-hydroxyceramide subclasses such as alpha-hydroxy-sphingosine ceramide and alpha-hydroxy-phytosphingosine ceramide were associated with a reduced proportion of the orthorhombic packing structure domain.

Saturated Fatty Acid Chain Length and Risk of Cardiovascular Disease: A Systematic Review.

The purpose of this systematic review was to evaluate the impact of saturated fatty acid chain lengths on the development of cardiovascular disease (CVD). The importance of replacement macronutrients is also discussed. PubMed, CINAHL, and Cochrane library were searched for relevant prospective cohort studies that measured SFA chain length via diet analysis through October of 2020. A second updated PubMed search was conducted from October 2020 to 7 August 2022. Five prospective cohort studies were added. All studies used food frequency questionnaires to assess dietary intake. For all five added studies, the main sources of saturated fat were palmitic and steric acid from meat and cheese. Most studies discovered an association with increased risk of CVD and long-chain saturated fatty acid intake, as well as a neutral (potentially beneficial) association with short- and medium-chain saturated fatty acids. Isocaloric substitutions were associated with a higher risk for CVD when saturated fats were replaced with refined carbohydrates and protein from meat, but a reduced or neutral impact when relaced with plant-based protein, unsaturated fat, or complex carbohydrates. When examining the impact of diet on CVD risk, it is critical to consider the macronutrient replacing saturated fat as well as the saturated fat chain length, whole foods, and diet patterns on CVD risk. The studies included in this review suggest that LCSFA (C12-18) may increase the risk for CVD development, while SCFA and MCFA (C4--C10) may be more beneficial or neutral.

Abiotic synthesis with plausible emergence for primitive phospholipid in aqueous microdroplets

Phospholipids are the protective layer of modern cells, but it is challenging for the formation of phospholipids that require a simple abiotic synthesis before the advent of primitive cells. Here, we reported the abiotic synthesis for lysophosphatidic acids (LPAs) with prebiotically plausible reactants in aqueous microdroplets under ambient conditions. The LPAs formation is carried out by fusing two microdroplets streams: one contains glycerol and pyrophosphate in water and the other one contains fatty acids in acetonitrile. Compared with the bulk solution, LPAs were generated in microdroplets without the addition of catalyst and heating. Conditions of reactant concentrations and microdroplet size varied and suggested that LPAs formation occurred near or at the microdroplet surface. The LPAs formation also showed chemoselective toward on chain-length of fatty acids. Finally, the formation of LPAs underwent two-step reactions with glycerol phosphorylation eliminating one water molecule followed by esterification with fatty acids. These results also implicated that pyrophosphate functioned as both catalysts and precursors in prebiotic LPAs synthesis. The approach using fusion aqueous microdroplets has desirable features in studying the substance exchange and interaction in atmosphere.

Using Molecular Dynamics Simulations to Understand the Effect of Fatty Acids Chain Length on Structural and Dynamic Properties of Deep Eutectic Solvents Based on Choline Chloride and Fatty Acids

AbstractThe binary mixtures of choline chloride and a series of fatty acids such as Caprylic acid (C8), Capric acid (C10), Lauric acid (C12), Myristic acid (14), and Palmitic acid (C16) have been prepared. The structural and dynamical properties of the eutectic mixture with the constant molar ratio of Ch+Cl−: FAs=1 : 1 was evaluated at 353 K. To analyze the intermolecular interactions in the binary mixtures, the 100 ns MD simulation was implemented using the NPT ensemble. The structure and properties of the binary mixtures were investigated to understand their molecular interactions. The results confirmed that the interaction between chloride ions and fatty acids has played an important role in interrupting the main interaction between the acids in the pure state. However, Interactions between chloride anion and the hydroxyl group of cations are more weakened in the presence of FAs with a shorter chain length. It is well known that there is a similar relationship between the intermolecular interactions and dynamics properties in distinctive structures of DES. Therefore, the other theme of this study is exploring the possible effect of intermolecular interactions on the self‐diffusion coefficients of species and determining the fatty acids that have stronger interactions with choline chloride salt to form the eutectic solvents. The diffusion coefficient of species was calculated by Einstein's equations. The results of dynamics properties showed the strong Hydrogen bonding network of the binary mixture of Caprylic acid and Choline chloride strongly affects molecular migrations.

Fatty Acid Composition of Comamonas testosteroni under Hexachlorobenzene Loading Conditions

Changes in the lipid composition in bacterial membranes are considered to be the most important adaptation mechanisms to adverse chemical factors. The aim of the study was to compare the hexachlorobenzene effects on the fatty acid composition of total lipids Comamonas testosteroni. Methods. The study was performed with C. testosteroni UCM B-400 and B-401, B-213 strains. Bacteria were grown in the Luria-Bertrani (LB) liquid medium containing 10 and 20 mg/L of hexachlorobenzene (HCB). After cultivation, the biomass was separated by centrifugation and the fatty acid composition of total lipids was determined through analyzing its methyl esters. To assess the cell membrane properties, such parameters as the lipid unsaturation index, the average carbon chain length of fatty acids, and the membrane viscosity index were determined. Results. In the fatty acids spectrum of C. testosteroni B-400 after cultivation in a medium containing 20 mg/L of HCB, the contents of unsaturated hexadecenoic (C16:1) and octadecenoic (C18:1) acids were lower by 10.6 and 5.5%, respectively, and that of saturated hexadecanoic (C16:0) acid was higher by 8.4%, compared to the control. The fatty acid composition of C. testosteroni B-401 was more stable compared to strain B-400. Collection strain C. testosteroni B-213 compared to strains isolated from soil with high HCB load, in the presence of 10 and 20 mg/L of HCB had the highest relative content of saturated hexadecanoic acid (C16:0) up to 38.33—40.7%. Unsaturated octadecenoic acid decreased at the doses 10 and 20 mg/L to 1.5—2% compared to the control. In all strains under the HCB impact, there was an increase in the relative content of C17-cyclopropanoic acid compared to control variants. Conclusions. C. testosteroni UCM B-400, B-401, and B-213 bacteria under cultivation conditions in HCB-containing medium, decreasing the degree of lipid unsaturation and increasing the relative content of C17-cyclopropanoic acid can be considered as the main mechanisms regulating the cytoplasmic membrane fluidity; the displaying of these protective reactions had a strain trait and did not depend on the adaptation in natural isolating places.

Targeted Sphingolipid Analysis in Heart, Gizzard, and Breast Muscle in Chickens Reveals Possible New Target Organs of Fumonisins.

Alteration of sphingolipid synthesis is a key event in fumonisins toxicity, but only limited data have been reported regarding the effects of fumonisins on the sphingolipidome. Recent studies in chickens found that the changes in sphingolipids in liver, kidney, lung, and brain differed greatly. This study aimed to determine the effects of fumonisins on sphingolipids in heart, gizzard, and breast muscle in chickens fed 20.8 mg FB1 + FB2/kg for 9 days. A significant increase in the sphinganine:sphingosine ratio due to an increase in sphinganine was observed in heart and gizzard. Dihydroceramides and ceramides increased in the hearts of chickens fed fumonisins, but decreased in the gizzard. The dihydrosphingomyelin, sphingomyelin, and glycosylceramide concentrations paralleled those of ceramides, although the effects were less pronounced. In the heart, sphingolipids with fatty acid chain lengths of 20 to 26 carbons were more affected than those with 14-16 carbons; this difference was not observed in the gizzard. Partial least squares-discriminant analysis on sphingolipids in the heart allowed chickens to be divided into two distinct groups according to their diet. The same was the case for the gizzard. Pearson coefficients of correlation among all the sphingolipids assayed revealed strong positive correlations in the hearts of chickens fed fumonisins compared to chickens fed a control diet, as well as compared to gizzard, irrespective of the diet fed. By contrast, no effect of fumonisins was observed on sphingolipids in breast muscle.

N-Terminally Lipidated Sialorphin Analogs-Synthesis, Molecular Modeling, In Vitro Effect on Enkephalins Degradation by NEP and Treatment of Intestinal Inflammation in Mice.

Pharmacotherapy for inflammatory bowel disease (IBD) is difficult, and some patients do not respond to currently available treatments. Therefore, the discovery of novel anti-IBD agents is imperative. Our aim was the synthesis of lipidated analogs of sialorphin and the in vitro characterization of their effect on the degradation of Met-enkephalin by neutral endopeptidase (NEP). We also investigated in vivo whether the most active inhibitor (peptide VIII) selected in the in vitro studies could be a potential candidate for the treatment of colitis. Peptides were synthesized by the solid-phase method. Molecular modeling technique was used to explain the effect of fatty acid chain length in sialorphin analogs on the ligand-enzyme interactions. The anti-inflammatory effect was evaluated in the dextran sulphate sodium (DSS)-induced model of colitis in mice. Peptide VIII containing stearic acid turned out to be in vitro the strongest inhibitor of NEP. We have also shown that the length of the chain of stearic acid fits the size of the grove of NEP. Peptides VII and VIII exhibited in vivo similar anti-inflammatory activity. Our results suggest that lipidation of sialorphin molecule is a promising direction in the search for NEP inhibitors that protect enkephalins.

Quantitative lipidomics reveals lipid perturbation in the liver of fatty liver hemorrhagic syndrome in laying hens

Fatty liver hemorrhagic syndrome (FLHS) is a metabolic disease that causes decreased egg production and even death in laying hens, which brings huge economic losses to the poultry industry. However, the pathogenesis of FLHS is unclear. The purpose of the present study was to identify the changes in lipid profile and the lipid species related to FLHS. In the present study, the FLHS disease model in Chinese commercial Jing Fen laying hens was induced by a high-energy low-protein diet. A lipidomics approach based on ultra-performance liquid chromatography-mass spectrometry coupled with multivariate statistical analysis was performed for the qualitative and quantitative analyses of the liver lipids. The results showed that a total of 29 lipid subclasses, including 1,302 lipid species, were detected and identified. Among them, the proportions of phosphatidylserine (Control/FLHS, 33.1% vs. 29.1%), phosphatidylethanolamine (22.7% vs. 15.5%), phosphatidylcholine (15.7% vs. 11.7%) and phosphatidylinositol (7% vs. 6%) were reduced, while triacylglycerol (7.1% vs. 18.3%) and diglyceride (3.9% vs. 11.7%) were increased. Between the Control and FLHS groups, distinct changes in lipid profile were observed in the score plots of principal component analysis and orthogonal partial least squares discriminant analysis. Twelve differential lipid species mainly involved in glycerophospholipid metabolism and linoleic acid metabolism were identified and considered to be related to the pathogenesis of FLHS. Fatty acid chain length and unsaturation were reduced, while the mRNA levels of elongation of very long chain fatty acids-2 (ELOVL2) were increased in the liver of laying hens with FLHS. Collectively, this study characterized the liver lipid profile and explored the changes in lipid species related to FLHS, which provided insights into the pathogenesis of FLHS from the view of lipid metabolism.

Water-Soluble Truncated Fatty Acid-Porphyrin Conjugates Provide Photo-Sensitizer Activity for Photodynamic Therapy in Malignant Mesothelioma.

Clinical trials evaluating intrapleural photodynamic therapy (PDT) are ongoing for mesothelioma. Several issues still hinder the development of PDT, such as those related to the inherent properties of photosensitizers. Herein, we report the synthesis, photophysical, and photobiological properties of three porphyrin-based photosensitizers conjugated to truncated fatty acids (C5SHU to C7SHU). Our photosensitizers exhibited excellent water solubility and high PDT efficiency in mesothelioma. As expected, absorption spectroscopy confirmed an increased aggregation as a consequence of extending the fatty acid chain length. In vitro PDT activity was studied using human mesothelioma cell lines (biphasic MSTO-211H cells and epithelioid NCI-H28 cells) alongside a non-malignant mesothelial cell line (MET-5A). The PDT effect of these photosensitizers was initially assessed using the colorimetric WST-8 cell viability assay and the mode of cell death was determined via flow cytometry of Annexin V-FITC/PI-stained cells. Photosensitizers appeared to selectively localize within the non-nuclear compartments of cells before exhibiting high phototoxicity. Both apoptosis and necrosis were induced at 24 and 48 h. As our pentanoic acid-derivatized porphyrin (C5SHU) induced the largest anti-tumor effect in this study, we put this forward as an anti-tumor drug candidate in PDT and photo-imaging diagnosis in mesothelioma.

Mass spectrometric based analysis of whole eggs dissolved in formic acid

We have developed a method for complete dissolution of whole eggs in formic acid that provides a new approach to analyzing egg biomolecules. As expected from prior work with extracted lipids, phosphatidylcholine represents the most abundant 31P NMR signal. A simplified methanol/chloroform partitioning method for separating the dissolved egg solution into metabolites, lipids and protein was performed and after ultra-high mass resolution and tandem MS fragmentation analyses several phosphatidylcholine molecules containing different fatty acid chain lengths as well as number and position of double bonds was detected. The MS based proteomic analysis further revealed 6 Gallus sequences annotated as 'uncharacterized' because they show no sequence homology with any other protein found in nature and thus, may represent proteins uniquely evolved to perform functions specific to chickens. Overall, this procedure is a rapid and facile means of characterizing in a high throughput and comprehensive manner, the molecular components of whole eggs.

Enrichment of nervonic acid in Acer truncatum Bunge oil by combination of two-stage molecular distillation, one-stage urea complexation and five-stage solvent crystallization

Nervonic acid is the world's first and only potent substance that can repair damaged nerve fibers and promote nerve cell regeneration with high nutritional value. The wide variety of fatty acids in plant oils and fats with similar structures makes the large-scale separation and purification of high-purity nervonic acid very difficult. A new combined process of molecular distillation, urea inclusion and solvent crystallization was established to prepare high-purity nervonic acid with the mixed fatty acids obtained after saponification and acidification of Acer truncatum Bunge oil as raw materials. First, according to the difference in the mean free path of fatty acids, molecular distillation was used to separate and remove C16 saturated fatty acid of palmitic acid and four C18–C20 fatty acids of stearic, oleic, linoleic, and linolenic acids. The content of C16–C20 fatty acids decreased from 72.92% to 19.22% after two-stage molecular distillation processes, in which the contents of saturated fatty acid of palmitic acid decreased to about 0.5%. Then, according to the difference in carbon chain length and saturation of fatty acid, the contents of C22–C24 saturated fatty acids of tetracosanoic and docosanoic acids decreased to 0.21% and 0.07% by urea inclusion with urea/free fatty acid preparation by saponification (SPOMFs) ratio as 0.6. In addition, all saturated fatty acids were basically separated. Finally, according to the difference in the solubility of fatty acids in solvents, the C18–C20 unsaturated fatty acids of oleic, linoleic, and linolenic acids and C22 unsaturated fatty acid of erucic acid were removed by solvent crystallization. The content of C18–C20 unsaturated fatty acids decreased to less than 5% with pentanol as the solvent after the first stage solvent crystallization. The content of erucic acid decreased to 3.47% with anhydrous ethanol as the solvent after the second to fifth stage solvent crystallization. The combined process of molecular distillation, urea inclusion and low temperature crystallization innovatively adopted an efficient, simple and easy-to-industrial solvent crystallization method to separate erucic and nervonic acids, obtaining nervonic acid with purity of 96.53% and final yield of 47.99%.

Structural changes in fasted state dietary mixed micelles upon solubilization of beta-carotene

It was aimed to investigate the structural changes taking place in duodenal mixed micelles (MM) at fasted state with the incorporation of fatty acids (FA) and the morphological transformations in these MMs upon solubilization of β-carotene (BCR) through coarse-grained (CG) molecular dynamics (MD) simulations. All simulations were performed with GROMACS 2019 simulation package using the Martini force field. Lauric acid (LA), stearic acid (SA) and linoleic acid (LNA) were used to explore the effects of FA chain length and unsaturation. Micelle swelling was observed with the incorporation of all FAs. The increase in size was in line with increasing FA chain length and unsaturation. MMs incorporating LA and SA were ellipsoidal in shape, while polyunsaturated LNA resulted in a worm-like MM. Upon solubilization of BCRs, swelling was observed only in the MMs with long-chain SA and LNA. No micelle growth was observed in the plain and LA MMs despite their smaller sizes. This was attributed to their low-density hydrophobic cores, which allowed a condensation effect induced by the interactions between BCRs and POPC tails. It is inferred that when the micelle is large enough to solubilize BCRs, whether or not swelling will take place depends on the core density. The increase in micelle size was very small in the MM incorporating LNA compared to that in the MM with SA, which was accompanied by an elliptical-to-cylindrical shape transformation. This was due to the fluid nature of the worm-like LNA micelle, which readily allowed the solubilization of 3 BCRs within its core. By resolving the internal structures of BCR incorporated MMs, this study gives valuable insight into the effects of FA chain length and unsaturation on the solubilization behavior of dietary MMs. The results are expected to give direction to the development of rational design strategies for effective BCR delivery systems.

Comparative lipidomics of Pichia pastoris using constitutive promoter reveals lipid diversity and variability at different growth phases.

Pichia pastoris is an expression platform widely used for foreign protein expression, while it is unknown how the global lipid profiles changed during the cultivation process, which is crucial for fermentation optimization and chassis design. Therefore, this study aimed to reveal the diverse lipid profiles of P. pastoris controlled by constitutive promoter of glyceraldehyde-3-phosphate dehydrogenase gene and to unravel their change in the lag, logarithmic, stationary, and death phases, using ultra-performance liquid chromatography/nano-electrospray ionization-tandem mass spectrometry. Two hundred forty lipid species across 11 lipid classes were detected, including various glycerolipids, glycerophospholipids, and sphingolipids. Pichia cells displayed high diversity and variability of lipids in lipid profile, relative intensity, phosphatidylinositol/phosphatidylserine ratio, fatty acid chain length, and unsaturation degree. Notably, increase of unsaturated triacylglycerol level was accompanied by rise of malondialdehyde level under oxidative stress. The increased ceramide with long fatty acid chain could be a key feature at death phase. This work deepened our understanding of the physiology of P. pastoris during cultivation and provided valuable information for further improvement of the P. pastoris expression system.

Consequences of Autophagy Deletion on the Age-Related Changes in the Epidermal Lipidome of Mice.

Autophagy is a controlled mechanism of intracellular self-digestion with functions in metabolic adaptation to stress, in development, in proteostasis and in maintaining cellular homeostasis in ageing. Deletion of autophagy in epidermal keratinocytes does not prevent the formation of a functional epidermis and the permeability barrier but causes increased susceptibility to damage stress and metabolic alterations and accelerated ageing phenotypes. We here investigated how epidermal autophagy deficiency using Keratin 14 driven Atg7 deletion would affect the lipid composition of the epidermis of young and old mice. Using mass spectrometric lipidomics we found a reduction of age-related accumulation of storage lipids in the epidermis of autophagy-deficient mice, and specific changes in chain length and saturation of fatty acids in several lipid classes. Transcriptomics and immunostaining suggest that these changes are accompanied by changes in expression and localisation of lipid and fatty acid transporter proteins, most notably fatty acid binding protein 5 (FABP5) in autophagy knockouts. Thus, maintaining autophagic activity at an advanced age may be necessary to maintain epidermal lipid homeostasis in mammals.

Medium-chain triglyceride production in Nannochloropsis via a fatty acid chain length discriminating mechanism.

Depending on their fatty acid (FA) chain length, triacylglycerols (TAGs) have distinct applications; thus, a feedstock with a genetically designed chain length is desirable to maximize process efficiency and product versatility. Here, ex vivo, in vitro, and in vivo profiling of the large set of type-2 diacylglycerol acyltransferases (NoDGAT2s) in the industrial oleaginous microalga Nannochloropsis oceanica revealed two endoplasmic reticulum-localized enzymes that can assemble medium-chain FAs (MCFAs) with 8-12 carbons into TAGs. Specifically, NoDGAT2D serves as a generalist that assembles C8-C18 FAs into TAG, whereas NoDGAT2H is a specialist that incorporates only MCFAs into TAG. Based on such specialization, stacking of NoDGAT2D with MCFA- or diacylglycerol-supplying enzymes or regulators, including rationally engineering Cuphea palustris acyl carrier protein thioesterase, Cocos nucifera lysophosphatidic acid acyltransferase, and Arabidopsis thaliana WRINKLED1, elevated the medium-chain triacylglycerol (MCT) share in total TAG 66-fold and MCT productivity 64.8-fold at the peak phase of oil production. Such functional specialization of NoDGAT2s in the chain length of substrates and products reveals a dimension of control in the cellular TAG profile, which can be exploited for producing designer oils in microalgae.

Formation of Intermediate Amylose Rice Starch-Lipid Complex Assisted by Ultrasonication.

Due to the potential reduction in starch availability, as well as the production of the distinct physico-chemical characteristics of starch in order to improve health benefits, the formation of starch–lipid complexes has attracted significant attention for improving the quantity of resistant starch (RS) content in starchy-based foods. The purpose of this research was to apply ultrasonication to produce intermediate amylose rice (Oryza sativa L.) cv. Noui Khuea (NK) starch–fatty acid (FA) complexes. The effects of ultrasonically synthesized conditions (ultrasonic time, ultrasonic amplitude, FA chain length) on the complexing index (CI) and in vitro digestibility of the starch–FA complex were highlighted. The optimum conditions were 7.5% butyric acid with 20% amplitude for 30 min, as indicated by a high CI and RS contents. The ultrasonically treated starch–butyric complex had the highest RS content of 80.78% with a V-type XRD pattern and an additional FTIR peak at 1709 cm−1. The increase in the water/oil absorption capacity and swelling index were observed in the starch–lipid complex. The pasting viscosity and pasting/melting temperatures were lower than those of native starch, despite the fact that it had a distinct morphological structure with a high proportion of flaky and grooved forms. The complexes were capable of binding bile acid, scavenging the DPPH radical, and stimulating the bifidobacterial proliferation better than native starch, which differed depending on the FA inclusion. Therefore, developing a rice starch–lipid complex can be achieved via ultrasonication.

Insight into the physicochemical properties and bioactivities of therapeutic deep eutectic solvents based on matrine and fatty acids

• THEDESs based on matrine and fatty acids were developed. • Physicochemical properties of THEDESs were investigated. • Antibacterial and anti-cancer activities and cytotoxicity of THEDESs were studied. Deep eutectic solvents (DESs), as a new type of green solvent, have shown great advantages of easy preparation, no purification needed after synthesis and great potential for application in various fields. Recently, a new type of drug delivery system called therapeutic deep eutectic solvent (THEDES) was developed when combining active pharmaceutical ingredients (APIs) into DES. Herein, we have constructed a series of new THEDES based on matrine (API) and fatty acids. Their physicochemical properties and bioactivities were investigated. In a temperature range from 298.15 K to 338.15 K, both density and viscosity declined with the increasing temperature. Besides, the density of THEDES decreased with the increasing alkyl chain length of fatty acids due to the enhancement of free volume, while the alkyl chain length displayed no influence on the viscosity of THEDES. Moreover, THEDESs showed better antibacterial activity on S. aureus as compared with matrine and the mixture solution of matrine and fatty acids at the same concentration. THEDESs also displayed better cell antiproliferative activities and higher cytotoxicity than that of matrine. Therefore, the results presented herein provides important basis for the further applications of matrine in the form of THEDES.

Improving the instant properties of kudzu powder by complexing with different chain-length fatty acids

The edible quality of starch paste formed by direct dispersion in boiling water is crucial to the design and production of instant starch-based products. In the present study, the kudzu powder was complexed with different chain-length fatty acids to improve its instant properties. The formation of V6-type kudzu powder-fatty acid complexes was initially characterized. Then, the impact of different chain-length fatty acids on instant properties of kudzu powder was characterized by measuring agglomeration rate and viscoelasticity. The agglomeration rate was decreased from 42.31% (native kudzu powder) to 0.08% (kudzu powder-myristic acid complex). Moreover, the viscoelasticity of the kudzu powder complexed with fatty acids (except for stearic acid) was stronger than that of native kudzu powder. These improvements were related to the formation of kudzu powder-fatty acid complexes with high thermal stability existed on the surface of complexed kudzu powder and extending the time for water to enter into complexed kudzu powder. Thus, all of kudzu powder could absorb sufficient water to avoid aggregating together that was involved into the formation of kudzu paste. This research had important implication for the preparation of instant starchy products that could be directly dispersed in hot water with high edible quality.

Engineering Yarrowia lipolytica to Produce Tailored Chain-Length Fatty Acids and Their Derivatives.

Microbial production of value-added chemicals derived from fatty acids is a sustainable alternative to petroleum-derived chemicals and unsustainable lipids from animals and plants. Fatty acids with different carbon chain lengths including short- (<C6), medium- (C6-C12), long- (C14-C20), and very-long- (>C20), with either even or odd number of carbons, have significantly different characteristics and wide applications in energy, material, medicine, and nutrition. Tailoring chain-length specificity of these compounds using metabolic engineering would be of high interest. Yarrowia lipolytica, as an oleaginous yeast, is a superior industrial chassis for the production of tailored chain-length fatty acids and their derivatives due to its hyper-oil-producing capability. In this Review, we cover metabolic engineering approaches that can lead to fatty acid chain length control in this microorganism. These approaches involve the manipulation of the fatty acid synthase, the thioesterase, the β-oxidation pathway, the elongation and desaturation pathway, the polyketide synthase-like polyunsaturated fatty acid synthase pathway, and the odd-chain fatty acids synthesis pathway. Finally, we also discuss alternative strategies that can be used in the future to tailored chain-length control.