Decanoic acid

Comparison of the Key Aroma Compounds in Fresh, Raw Ginger (Zingiber officinale Roscoe) from China and Roasted Ginger by Application of Aroma Extract Dilution Analysis.[Pubmed:33301679]

J Agric Food Chem. 2020 Dec 10.

By application of a comparative aroma extract dilution analysis on the volatile fractions isolated by solvent extraction and solvent-assisted flavor evaporation (SAFE) from fresh raw Chinese ginger (Zingiber officinale Roscoe) and roasted ginger, 21 or 33 odorants, respectively, with flavor dilution (FD) factors in the range of 32-4096 were identified. In raw ginger, the highest FD factors were found for (E)-isoeugenol, 1,8-cineol, vanillin, geranial, and linalool. After roasting, in particular, the FD factors of 3-(methylthio)propanal (cooked potato-like), 4-hydroxy-2,5-dimethyl-3(2H)-furanone (caramel-like), 3-hydroxy-4,5-dimethyl-2(5H)-furanone (seasoning-like), and geraniol were substantially increased. The application of static headspace/olfactometry (SHO) on ground raw ginger revealed a high FD factor for highly volatile acetaldehyde which clearly decreased after roasting. By contrast, the SHO application revealed high FD factors for malty smelling methylpropanal and 3-methylbutanal, which both were exclusively detected in roasted ginger. Thirteen odorants, namely, Decanoic acid, (Z)-2-decenal, (Z)-4-decenal, (E)-4,5-epoxy-(E)-2-decenal, (E)-4,5-epoxy-(E)-2-undecenal, fenchol, (Z)-3-hexenal, 3-hydroxy-4,5-dimethyl-2(5H)-furanone, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 3-methyl-2-buten-1-thiol, 2-methylpropanal, (E)-2-nonenal, and 1-nonen-3-one, were identified in ginger for the first time. Chiral analysis showed a much higher percent by weight portion for the (R)-enantiomer in citronellal, citronellol, and linalool, which was not much changed during pan-frying.

Vitamin D3 bioaccessibility: Influence of fatty acid chain length, salt concentration and l-alpha-phosphatidylcholine concentration on mixed micelle formation and delivery of vitamin D3.[Pubmed:33277128]

Food Chem. 2020 Nov 25:128722.

Vitamin D (VD) is a fat-soluble vitamin with high deficiency levels evident globally. Bioaccessibility of VD is influenced by formation of mixed micelles (MM) during digestion. This study assessed the impact of fatty acid (FA) type, phospholipid concentration on MM formation and stability of MM to salts. MM formation occurred at NaCl and KCl concentrations ranging from 20 to 100 mM, when octanoic acid (C8) or stearic acid (C18) were used. MM hydrodynamic size increased with increasing l-alpha-phosphatidylcholine concentration (1.5-7.5 mM) for both C8 and C18, above which concentration MM did not form. FA chain length impacted MM with hydrodynamic size increasing from 3.8 nm for Decanoic acid (C10) to 4.4 nm for C18. VD3 incorporation in MM was not influenced by the FA used (C10 or C18). Understanding stability and formation of MM and VD3 loading is an essential first step towards manipulating food structures for improving delivery of VD.

Supramolecular Solvent-Based Microextraction of Selected Anticonvulsant and Nonsteroidal Anti-Inflammatory Drugs from Sediment Samples.[Pubmed:33271858]

Molecules. 2020 Dec 1;25(23). pii: molecules25235671.

The increase in the production and consumption of pharmaceuticals increases their presence in the global environment, which may result in direct threats to living organisms. For this reason, there is a need for new methods to analyze drugs in environmental samples. Here, a new procedure for separating and determining selected drugs (diclofenac, ibuprofen, and carbamazepine) from bottom sediment and water samples was developed. Drugs were determined by ultra-high performance liquid chromatography coupled with an ultraviolet detector (UHPLC-UV). In this work, a universal and single-step sample treatment, based on supramolecular solvents (SUPRAS), was proposed to isolate selected anticonvulsants and nonsteroidal anti-inflammatory drugs (NSAIDs) from sediment samples. The following parameters were experimentally selected: composition of the supramolecular solvent (composition THF:H2O (v/v), amount of Decanoic acid), volume of extractant, sample mass, extraction time, centrifugation time, and centrifugation speed. Finally, the developed procedure was validated. A Speedisk procedure was also developed to extract selected drugs from water samples. The recovery of analytes using the SUPRAS procedure was in the range of 88.8-115%, while the recoveries of the Speedisk solid-phase extraction procedure ranged from 81.0-106%. The effectiveness of the sorption of the tested drugs by sediment was also examined.

Antibiofilm and antifungal activities of medium-chain fatty acids against Candida albicans via mimicking of the quorum-sensing molecule farnesol.[Pubmed:33252828]

Microb Biotechnol. 2020 Nov 30.

Candida biofilms are tolerant to conventional antifungal therapeutics and the host immune system. The transition of yeast cells to hyphae is considered a key step in C. albicans biofilm development, and this transition is inhibited by the quorum-sensing molecule farnesol. We hypothesized that fatty acids mimicking farnesol might influence hyphal and biofilm formation by C. albicans. Among 31 saturated and unsaturated fatty acids, six medium-chain saturated fatty acids, that is, heptanoic acid, octanoic acid, nonanoic acid, Decanoic acid, unDecanoic acid and lauric acid, effectively inhibited C. albicans biofilm formation by more than 75% at 2 microg ml(-1) with MICs in the range 100-200 microg ml(-1) . These six fatty acids at 2 microg ml(-1) and farnesol at 100 microg ml(-1) inhibited hyphal growth and cell aggregation. The addition of fatty acids to C. albicans cultures decreased the productions of farnesol and sterols. Furthermore, down-regulation of several hyphal and biofilm-related genes caused by heptanoic or nonanoic acid closely resembled the changes caused by farnesol. In addition, nonanoic acid, the most effective compound diminished C. albicans virulence in a Caenorhabditis elegans model. Our results suggest that medium-chain fatty acids inhibit more effectively hyphal growth and biofilm formation than farnesol.

Determination of microbial diversities and aroma characteristics of Beitang shrimp paste.[Pubmed:33246688]

Food Chem. 2020 Nov 23:128695.

Beitang shrimp paste (BSP) is fermented by different parts of shrimp, such as the head (H), meat (M), or the whole shrimp (S and W). Microbial communities of BSP were dominated by Firmicutes and Proteobacteria at the phyla level and Tetragenococcus at the genus level. However, the microbial diversity of M was the lowest than the others. Non-dominant bacterial communities were presented by a mutual symbiotic model in BSP fermentation. Tetragenococcus, Halanaerobium, Streptococcus, and Brevundimonas were positively correlated with the biosynthesis of amino acids, fatty acids, and metabolic cofactors; Marinilactibacillus and Pseudomonas might be the main contributors to inorganic sulfides, nitrogen oxides, and long-chain alkanes in BSP; Psychrobacter was closely related to the ester characteristics of methyl palmitoleate and methyl hexadecanoate in H. Halanaerobium and Streptococcus promoted the production of pyrazines in S. Tetragenococcus was positively correlated with acetic acid, Decanoic acid, and palmitic acid that improved the sour aroma of M. The relationship between bacteria and aroma formation under different raw materials was expected to improve the quality of BSP.

Decanoic acid modification enhances the antibacterial activity of PMAP-23RI-Dec.[Pubmed:33141035]

Eur J Pharm Sci. 2020 Oct 22:105609.

Antimicrobial peptides are a new type of antibacterial drugs with a broad antibacterial spectrum. Based on our previous research, PMAP-23RI-Dec was designed by modifying the C-terminal of PMAP-23RI with Decanoic acid. In this study, we measured the antibacterial activity, stability, hemolysis, and cytotoxicity of PMAP-23RI-Dec. The mechanism of PMAP-23RI-Dec on biofilm and cell membranes were also studied. The results show that PMAP-23RI-Dec exhibited high antibacterial activity and stability, but the hemolytic activity and cytotoxicity of PMAP-23RI-Dec were not enhanced. Moreover, PMAP-23RI-Dec could inhibit biofilm formation at low concentrations, and enhance the killing effect on bacteria by changing the permeability of their cell membranes. Finally, PMAP-23RI-Dec reduced Pseudomonas aeruginosa GIM1.551 and Staphylococcus aureus ATCC25923 damage to organs, and showed superior efficacy against peritonitis. PMAP-23RI-Dec also reduced the scope of abscess and alleviated wound infections. Our research indicated that PMAP-23RI-Dec is a new antibacterial agent with potential clinical application.

Lipase-catalysed synthesis of mono- and di-acyl esters of glyceryl caffeate in propylene carbonate and their antioxidant properties in tuna oil.[Pubmed:33098933]

J Biotechnol. 2020 Oct 22. pii: S0168-1656(20)30291-1.

Development of new non-toxic antioxidants with diverse hydrophobic properties is important due to growing concerns about the toxicity of artificial oil-soluble antioxidants, the comparatively low effectiveness of natural options, and the complex role hydrophobicity plays in antioxidant effectiveness. Using caffeic acid, a naturally occurring phenolic acid with potent antioxidant activity, a range of glyceryl caffeate esters (decanoate and palmitate) were prepared using lipase-catalysed esterification reactions. Glyceryl-1-caffeate (GC) was prepared from ethyl caffeate and glycerol (acting as both the solvent and the substrate), catalysed by immobilised Candida Antarctica lipase B (Novozym-435) at 80 degrees C under vacuum. Esterification of GC with Decanoic acid using immobilised Thermomyces lanuginosus lipase (TLIM) or Novozym-435 was found to be selective towards mono-acylated or di-acylated products, respectively. The reaction was performed in an unconventional solvent, propylene carbonate (PC), which has many of the attributes of a green solvent. Product conversions in PC were comparable to the best performing conventional solvents. In contrast to conventional volatile solvents, the low volatility of PC allowed the reaction to be performed under vacuum, without the need for molecular sieves for removal of water produced during the reaction. Diisopropyl ether was effective at extracting the more lipophilic products from PC. Both the lipase (Novozym-435) and PC were reused four times with only a small loss in conversion efficiency. Glyceryl caffeate esters performed much better than alpha-tocopherol at protecting bulk tuna oil from oxidation (analysed using Rancimat). A comparison of glyceryl caffeate esters (decanoate/palmitate and mono-/di-acylated) showed that their antioxidant effectiveness in bulk tuna oil was not affected by chain-length, but compounds containing only one fatty ester were slightly more effective than those containing two fatty esters.

Effects of a Small Increase in Carbon Dioxide Pressure during Fermentation on Wine Aroma.[Pubmed:33086729]

Foods. 2020 Oct 19;9(10). pii: foods9101496.

The present study tested the effect of a slight increase in pressure (from 0 to 1 bar) during the fermentation on the wine aroma profile. Fermentations were carried out with a commercial dry yeast on Sangiovese juice in the absence of berry skins. The wine samples fermented under slight overpressure conditions were found to be significantly different from the control samples produced at atmospheric pressure in relation to several chemical compounds. Concentrations of many esters (i.e., isoamyl acetate, ethyl acetate, ethyl hexanoate, hexyl acetate, ethyl dodecanoate, and ethyl tetradecanoate), and acids (i.e., hexanoic acid, octanoic acid, and Decanoic acid) increased, while concentrations of two acids (i.e., isobutyric and isovaleric acid) decreased. These differences, notably the higher concentration of esters, are usually associated with a more intense fruity attribute. Triangular sensory tests revealed that the significant chemical differences were also perceivable; hence, introducing a slight pressure increase during the alcoholic fermentation could be a useful tool in managing the aroma profile of wine.

Dynamic Metabolome Analysis Reveals the Metabolic Fate of Medium-Chain Fatty Acids in AML12 Cells.[Pubmed:33073987]

J Agric Food Chem. 2020 Oct 28;68(43):11997-12010.

Several studies in hepatocyte cell lines reported that medium-chain fatty acids (MCFAs) with 6-12 carbons showed different metabolic properties from long-chain fatty acids (LCFAs). However, these studies reported unclear effects of different fatty acid molecules on hepatocyte metabolism. This study is aimed to capture the metabolic kinetics of MCFA assimilation in AML12 cells treated with octanoic acid (FA 8:0), Decanoic acid (FA 10:0), or lauric acid (FA12:0) [LCFA; oleic acid (FA 18:1)] via metabolic profiling and dynamic metabolome analysis with (13)C-labeling. The concentrations of total ketone bodies in the media of cells treated with FA 8:0 or FA 10:0 were 3.22- or 3.69-fold higher than those obtained with FA 18:1 treatment, respectively. FA 12:0 treatment did not significantly increase ketone body levels compared to DMSO treatment (control), whereas FA 12:0 treatment increased intracellular triacylglycerol (TG) levels 15.4 times compared to the control. Metabolic profiles of FA 12:0-treated samples differed from those of the FA 8:0-treated and FA 10:0-treated samples, suggesting that metabolic assimilation of MCFAs differed significantly depending on the MCFA type. Furthermore, the dynamic metabolome analysis clearly revealed that FA 8:0 was rapidly and quantitatively oxidized to acetyl-CoA and assimilated into ketone bodies, citrate cycle intermediates, and glucogenic amino acids but not readily into TGs.

Characterization of the key aroma compounds in Yunnan goat milk cake using a sensory-directed flavor analysis.[Pubmed:33063315]

J Food Sci. 2020 Nov;85(11):3981-3997.

To identify the key aroma compounds in Yunnan goat milk cake, seven varieties of milk cake samples were subjected to sensory analysis and gas chromatography-mass spectrometry (GC-MS), gas chromatography-olfactometry (GC-O), aroma recombination, omission, and addition tests. The GC-MS results revealed 53 compounds with aroma characteristics in all the samples. A further comparison of odor activity values and aroma intensities (AI) revealed 25 of these compounds as the initial key aroma compounds. The contributions of these key aroma compounds to the sensory attributes were determined using a partial least squares regression. Of these compounds, 2-heptanone and 2-nonanone were closely related to the "milky" and "cheesy" attributes and were highly abundant in the samples from Kunming. Fatty acids, including butanoic acid, hexanoic acid, octanoic acid, and Decanoic acid, were the most abundant compounds detected in the milk cakes. These fatty acids were closely related to the "rancid" and "animalic (goat)" attributes and were largely detected in the samples from Dali Dengchuan and Dali Xiaguan. Sensory-directed aroma recombination, omission, and addition tests further validated the important contributions of ethyl butyrate, benzaldehyde, 3-methyl-1-butanol, 2-heptanone, hexanoic acid, and octanoic acid to the overall sensory properties. Moreover, ethyl butyrate, benzaldehyde, and 2-heptanone, when added, had evident inhibitory or masking effects on the AI of "sour," "rancid," and "animalic (goat)" attributes. PRACTICAL APPLICATION: Goat milk cake is a popular acid-curd cheese in Yunnan, China, however, our limited knowledge to its key aroma compounds restricts its development and industrial production. In this study, a sensory-directed flavor analysis was used to characterized the key aroma compounds of Yunnan goat milk cake, which will help to enhance our understanding on the flavor profile of Yunnan goat milk cake and provide a reference for optimizing the flavor feature and organoleptic quality of this fresh goat cheese.

Transformation of Microbial Negative Correlations into Positive Correlations by Saccharomyces cerevisiae Inoculation during Pomegranate Wine Fermentation.[Pubmed:33036987]

Appl Environ Microbiol. 2020 Nov 24;86(24). pii: AEM.01847-20.

The application of starter is a common practice to accelerate and steer the pomegranate wine fermentation process. However, the use of starter needs a better understanding of the effect of the interaction between the starter and native microorganisms during alcoholic fermentation. In this study, high-throughput sequencing combined with metabolite analysis was applied to analyze the effect of commercial Saccharomyces cerevisiae inoculation on the native fungal community interaction and metabolism during pomegranate wine fermentation. Results showed that there were diverse native fungi in pomegranate juice, including Hanseniaspora uvarum, Hanseniaspora valbyensis, S. cerevisiae, Pichia terricola, and Candida diversa Based on ecological network analysis, we found that S. cerevisiae inoculation transformed the negative correlations into positive correlations among the native fungal communities and decreased the Granger causalities between native yeasts and volatile organic compounds. This might lead to decreased contents of isobutanol, isoamylol, octanoic acid, Decanoic acid, ethyl laurate, ethyl acetate, ethyl hexadecanoate, phenethyl acetate, and 2-phenylethanol during fermentation. This study combined correlation and causality analysis to gain a more integrated understanding of microbial interaction and the fermentation process. It provided a new strategy to predict certain behaviors between inoculated and selected microorganisms and those coming directly from the fruit.IMPORTANCE Microbial interactions play an important role in flavor metabolism during traditional food and beverage fermentation. However, we understand little about how selected starters influence interactions among native microorganisms. In this study, we found that S. cerevisiae inoculation changed the interactions and metabolisms of native fungal communities during pomegranate wine fermentation. This study not only suggests that starter inoculation should take into account the positive features of starters but also characterizes the microbial interactions established among the starters and the native communities. It may be helpful to select appropriate starter cultures for winemakers to design different styles of wine.

Do Deep Eutectic Solvents Form Uniform Mixtures Beyond Molecular Microheterogeneities?[Pubmed:32945665]

J Phys Chem B. 2020 Oct 15;124(41):9126-9135.

We have performed small-angle neutron scattering in a momentum transfer range (0.05 < Q < 0.5 A(-1)) to study long-range order and concentration fluctuations in deep eutectic solvents (DESs) and their aqueous solutions. Ethaline (choline chloride/ethylene glycol), glycerol/lactic acid, and menthol/Decanoic acid mixtures were selected to illustrate individually the case of ionic, nonionic, and hydrophobic mixtures. Carefully designed isotopic labeling was used to emphasize selectively the spatial correlations between the different solvent components. For ethaline DESs and their aqueous solutions, a weak low-Q peak observed only for certain compositions and some partial structure factors revealed the mesoscopic segregation of ethylene glycol molecules that do not participate in the solvation of ionic units, either because they are in excess with respect to the eutectic stoichiometry (1:4 neat ethaline) or substituted by water (4w-ethaline and higher aqueous dilutions). For the nonionic hydrophilic solutions, such a mesoscopic segregation was not observed. This indicates that the better balanced interactions between the three nonionic H-bonded components (water, lactic acid, and glycerol) favor homogeneous mixing. For the hydrophobic DESs, we observed an excess of coherent scattering intensity centered at Q = 0, which could be reproduced by a model of noninteracting spherical domains. Local concentration fluctuations are not excluded either. However, unlike liquid mixtures with a tendency to demix, we have found no evidence of expansion of domains with different compositions to a large scale.

Decanoic acid inhibits mTORC1 activity independent of glucose and insulin signaling.[Pubmed:32879008]

Proc Natl Acad Sci U S A. 2020 Sep 22;117(38):23617-23625.

Low-glucose and -insulin conditions, associated with ketogenic diets, can reduce the activity of the mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway, potentially leading to a range of positive medical and health-related effects. Here, we determined whether mTORC1 signaling is also a target for Decanoic acid, a key component of the medium-chain triglyceride (MCT) ketogenic diet. Using a tractable model system, Dictyostelium, we show that Decanoic acid can decrease mTORC1 activity, under conditions of constant glucose and in the absence of insulin, measured by phosphorylation of eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1). We determine that this effect of Decanoic acid is dependent on a ubiquitin regulatory X domain-containing protein, mediating inhibition of a conserved Dictyostelium AAA ATPase, p97, a homolog of the human transitional endoplasmic reticulum ATPase (VCP/p97) protein. We then demonstrate that Decanoic acid decreases mTORC1 activity in the absence of insulin and under high-glucose conditions in ex vivo rat hippocampus and in tuberous sclerosis complex (TSC) patient-derived astrocytes. Our data therefore indicate that dietary Decanoic acid may provide a new therapeutic approach to down-regulate mTORC1 signaling.