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1.
Molecules ; 29(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38611800

RESUMO

4-Chloroisocoumarin compounds have broad inhibitory properties against serine proteases. Here, we show that selected 3-alkoxy-4-chloroisocoumarins preferentially inhibit the activity of the conserved serine protease High-temperature requirement A of Chlamydia trachomatis. The synthesis of a new series of isocoumarin-based scaffolds has been developed, and their anti-chlamydial properties were investigated. The structure of the alkoxy substituent was found to influence the potency of the compounds against High-temperature requirement A, and modifications to the C-7 position of the 3-alkoxy-4-chloroisocoumarin structure attenuate anti-chlamydial properties.


Assuntos
Álcoois , Chlamydia trachomatis , Inibidores de Proteases , Inibidores de Proteases/farmacologia , Terapia Enzimática , Isocumarinas , Serina Endopeptidases , Serina Proteases
2.
Helicobacter ; 29(2): e13064, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38459689

RESUMO

BACKGROUND: Helicobacter pylori (H. pylori) infection is the most extensively studied risk factor for gastric cancer. As with any bacteria, H. pylori will release distinctive odors that result from an emission of volatile metabolic byproducts in unique combinations and proportions. Effectively capturing and identifying these volatiles can pave the way for the development of innovative and non-invasive diagnostic methods for determining infection. Here we characterize the H. pylori volatilomic signature, pinpoint potential biomarkers of its presence, and evaluate the variability of volatilomic signatures between different H. pylori isolates. MATERIALS AND METHODS: Using needle trap extraction, volatiles in the headspace above H. pylori cultures were collected and, following thermal desorption at 290°C in a splitless mode, were analyzed using gas chromatography-mass spectrometry. The resulting volatilomic signatures of H. pylori cultures were compared to those obtained from an analysis of the volatiles in the headspace above the cultivating medium only. RESULTS: Amongst the volatiles detected, 21 showed consistent differences between the bacteria cultures and the cultivation medium, with 11 compounds being elevated and 10 showing decreased levels in the culture's headspace. The 11 elevated volatiles are four ketones (2-pentanone, 5-methyl-3-heptanone, 2-heptanone, and 2-nonanone), three alcohols (2-methyl-1-propanol, 3-methyl-1-butanol, and 1 butanol), one aromatic (styrene), one aldehyde (2-ethyl-hexanal), one hydrocarbon (n-octane), and one sulfur compound (dimethyl disulfide). The 10 volatiles with lower levels in the headspace of the cultures are four aldehydes (2-methylpropanal, benzaldehyde, 3-methylbutanal, and butanal), two heterocyclic compounds (2-ethylfuran and 2-pentylfuran), one ketone (2-butanone), one aromatic (benzene), one alcohol (2-butanol) and bromodichloromethane. Of the volatile species showing increased levels, the highest emissions are found to be for 3-methyl-1-butanol, 1-butanol and dimethyl disulfide. Qualitative variations in their emissions from the different isolates was observed. CONCLUSIONS: The volatiles emitted by H. pylori provide a characteristic volatilome signature that has the potential of being developed as a tool for monitoring infections caused by this pathogen. Furthermore, using the volatilome signature, we are able to differentiate different isolates of H. pylori. However, the volatiles also represent potential confounders for the recognition of gastric cancer volatile markers.


Assuntos
Dissulfetos , Infecções por Helicobacter , Helicobacter pylori , Pentanóis , Neoplasias Gástricas , Humanos , Álcoois
3.
Chem Pharm Bull (Tokyo) ; 72(3): 303-308, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38479853

RESUMO

Amine-free phosphorylation of various alcohols was developed with 4-methylpyridine N-oxide in the presence of 4 Å molecular sieves at room temperature. This mild method gave various phosphorylated products in high yield and could be applied to acid- or base-sensitive substrates. Furthermore, this method was also effective for the chemoselective phosphorylation of diols or polyols.


Assuntos
Álcoois , Óxidos , Picolinas , Aminas , Fosforilação , Catálise
4.
Nat Commun ; 15(1): 2523, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514642

RESUMO

Prostaglandins have garnered significant attention from synthetic chemists due to their exceptional biological activities. In this report, we present a concise chemoenzymatic synthesis method for several representative prostaglandins, achieved in 5 to 7 steps. Notably, the common intermediate bromohydrin, a radical equivalent of Corey lactone, is chemoenzymatically synthesized in only two steps, which allows us to complete the synthesis of prostaglandin F2α in five steps on a 10-gram scale. The chiral cyclopentane core is introduced with high enantioselectivity, while the lipid chains are sequentially incorporated through a cost-effective process involving bromohydrin formation, nickel-catalyzed cross-couplings, and Wittig reactions. This cost-efficient synthesis route for prostaglandins holds the potential to make prostaglandin-related drugs more affordable and facilitate easier access to their analogues.


Assuntos
Álcoois , Prostaglandinas
5.
Food Res Int ; 182: 114077, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38519167

RESUMO

Fruits flavor deterioration is extremely likely to occur during post-harvest storage, which not only damages quality but also seriously affects its market value. This work focuses on the study of fruits deterioration odorants during storage by describing their chemical compositions (i.e., alcohols, aldehydes, acids, and sulfur-containing compounds). Besides, the specific flavor deterioration mechanisms (i.e., fermentation metabolism, lipid oxidation, and amino acid degradation) inducing by factors (temperature, oxygen, microorganisms, ethylene) are summarized. Moreover, quality control strategies to mitigate fruits flavor deterioration by physical (temperature control, hypobaric treatment, UV-C, CA) and chemical (1-MCP, MT, NO, MeJA) techniques are also proposed. This review will provide useful references for fruits flavor control technologies development.


Assuntos
Frutas , Odorantes , Frutas/química , Aldeídos/análise , Álcoois/análise , Fermentação
6.
Food Res Int ; 182: 114187, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38519195

RESUMO

The flavor profiles of fresh and aged fermented peppers obtained from four varieties were thoroughly compared in this study. A total of 385 volatile compounds in fermented pepper samples were detected by flavoromics (two-dimensional gas chromatography-time-of-flight mass spectrometry). As fermentation progressed, both the number and the total concentration of volatile compounds changed, with esters, alcohols, acids, terpenoids, sulfur compounds, and funans increasing, whereas hydrocarbons and benzenes decreased. In contrast to the fresh fermented peppers, the aged fermented samples exhibited lower values of pH, total sugars, and capsaicinoids but higher contents of organic acids and free amino acids. Furthermore, the specific differences and characteristic aroma substances among aged fermented peppers were unveiled by multivariate statistical analysis. Overall, 64 volatiles were screened as differential compounds. In addition, Huanggongjiao samples possessed the most abundant differential volatiles and compounds with odor activity values > 1, which were flavored with fruity, floral, and slightly phenolic odors. Correlation analysis demonstrated that the levels of 23 key aroma compounds (e.g., ethyl 2-methylbutyrate, 1-butanol, and ethyl valerate) showed a significantly positive correlation with Asp, Glu and 5 organic acids. By contrast, there is a negative association between the pH value and total sugar. Overall, aging contributed significantly to the flavor attributes of fermented peppers.


Assuntos
Frutas , Piper nigrum , Frutas/química , Odorantes/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Álcoois/análise , Fermentação , Ácidos/análise
7.
J Agric Food Chem ; 72(11): 5766-5776, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38447044

RESUMO

The aromatic amino acids tryptophan, phenylalanine, and tyrosine are targets for oxidation during food processing. We investigated whether S. cerevisiae can use nonproteinogenic aromatic amino acids as substrates for degradation via the Ehrlich pathway. The metabolic fate of seven amino acids (p-, o-, m-tyrosine, 3,4-dihydroxyphenylalanine (DOPA), 3-nitrotyrosine, 3-chlorotyrosine, and dityrosine) in the presence of S. cerevisiae was assessed. All investigated amino acids except dityrosine were metabolized by yeast. The amino acids 3-nitrotyrosine and o-tyrosine were removed from the medium as fast as p-tyrosine, and m-tyrosine, 3-chlorotyrosine, and DOPA more slowly. In summary, 11 metabolites were identified by high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS). DOPA, 3-nitrotyrosine, and p-tyrosine were metabolized predominantly to the Ehrlich alcohols, whereas o-tyrosine and m-tyrosine were metabolized predominantly to α-hydroxy acids. Our results indicate that nonproteinogenic aromatic amino acids can be taken up and transaminated by S. cerevisiae quite effectively but that decarboxylation and reduction to Ehrlich alcohols as the final metabolites is hampered by hydroxyl groups in the o- or m-positions of the phenyl ring. The data on amino acid metabolism were substantiated by the analysis of five commercial beer samples, which revealed the presence of hydroxytyrosol (ca. 0.01-0.1 mg/L) in beer for the first time.


Assuntos
Aminoácidos Aromáticos , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Aminoácidos Aromáticos/metabolismo , Espectrometria de Massas em Tandem , Tirosina/metabolismo , Aminoácidos/metabolismo , Di-Hidroxifenilalanina/metabolismo , Álcoois/metabolismo
8.
Int J Mol Sci ; 25(6)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38542218

RESUMO

This study addresses the pressing issues of energy production and consumption, in line with global sustainable development goals. Focusing on the potential of alcohols as "green" alternatives to traditional fossil fuels, especially in biofuel applications, we investigate the thermochemical properties of three alcohols (n-propanol, n-butanol, n-pentanol) blended with sunflower oil. The calorimetric analysis allows for the experimental determination of excess enthalpies in pseudo-binary mixtures at 303.15 K, revealing similarities in the trends of the curves (dependence on concentrations) but with different values for the excess enthalpies for each mixture. Despite the structural differences of the alcohols studied, the molar excess enthalpy values exhibit uniformity, suggesting consistent mixing behavior. The peak values of excess enthalpies for systems with sunflower oil and n-propanol, n-butanol and n-pentanol are, respectively, 3255.2 J/mole, 3297.4 J/mole and 3150.1 J/mole. Both the NRTL and Redlich-Kister equations show satisfactory agreement with the obtained values.


Assuntos
Álcoois , Biocombustíveis , Pentanóis , Álcoois/química , Óleo de Girassol , 1-Propanol , 1-Butanol
9.
Plant Signal Behav ; 19(1): 2331894, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38516998

RESUMO

A bacterium growing on infected leaves of Hydrocotyle umbellata, commonly known as dollarweed, was isolated and identified as Pantoea ananatis. An ethyl acetate extract of tryptic soy broth (TSB) liquid culture filtrate of the bacterium was subjected to silica gel chromatography to isolate bioactive molecules. Indole was isolated as the major compound that gave a distinct, foul odor to the extract, together with phenethyl alcohol, phenol, tryptophol, N-acyl-homoserine lactone, 3-(methylthio)-1-propanol, cyclo(L-pro-L-tyr), and cyclo(dehydroAla-L-Leu). This is the first report of the isolation of cyclo(dehydroAla-L-Leu) from a Pantoea species. Even though tryptophol is an intermediate in the indoleacetic acid (IAA) pathway, we were unable to detect or isolate IAA. We investigated the effect of P. ananatis inoculum on the growth of plants. Treatment of Lemna paucicostata Hegelm plants with 4 × 109 colony forming units of P. ananatis stimulated their growth by ca. five-fold after 13 days. After 13 days of treatment, some control plants were browning, but treated plants were greener and no plants were browning. The growth of both Cucumis sativus (cucumber) and Sorghum bicolor (sorghum) plants was increased by ca. 20 to 40%, depending on the growth parameter and species, when the rhizosphere was treated with the bacterium after germination at the same concentration. Plant growth promotion by Pantoea ananatis could be due to the provision of the IAA precursor indole.


Assuntos
Álcoois , Centella , Indóis , Pantoea , Pantoea/química , Pantoea/metabolismo , Plantas/microbiologia
10.
Int J Mol Sci ; 25(4)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38396889

RESUMO

A potential strain, Paenibacillus sp. JNUCC32, was isolated and subjected to whole-genome sequencing. Genome functional annotation revealed its active metabolic capabilities. This study aimed to investigate the pivotal secondary metabolites in the biological system. Fermentation and extraction were performed, resulting in the isolation of seven known compounds: tryptophol (1), 3-(4-hydroxyphenyl)propionic acid (2), ferulic acid (3), maculosin (4), brevianamide F (5), indole-3-acetic acid (6), and butyric acid (7). Tryptophol exhibited favorable pharmacokinetic properties and demonstrated certain tyrosinase inhibitory activity (IC50 = 999 µM). For further analysis of its inhibition mechanism through molecular docking and molecular dynamics (MD) simulation, tryptophol formed three hydrogen bonds and a pro-Michaelis complex with tyrosinase (binding energy = -5.3 kcal/mol). The MD simulation indicated favorable stability for the tryptophol-mushroom tyrosinase complex, primarily governed by hydrogen bond interactions. The crucial residues VAL-283 and HIS-263 in the docking were also validated. This study suggests tryptophol as a potential candidate for antibrowning agents and dermatological research.


Assuntos
Álcoois , Indóis , Simulação de Dinâmica Molecular , Monofenol Mono-Oxigenase , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/metabolismo , Inibidores Enzimáticos/farmacologia
11.
Chem Pharm Bull (Tokyo) ; 72(2): 234-239, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38417869

RESUMO

The first lactam-type 2-iodobenzamide catalysts, 8-iodoisoquinolinones 8 (IB-lactam) and 9 (MeO-IB-lactam), were developed. These catalysts have a conformationally rigid 6/6 bicyclic lactam structure and are more reactive than the previously reported catalysts 2-iodobenzamides 4 (IBamide) and 5 (MeO-IBamide) for the oxidation of alcohols. The lactam structure could form an efficient intramolecular I---O interaction, depending on the size of the lactam ring.


Assuntos
Iodo , Álcoois/química , Catálise , Iodo/química , Lactamas , Oxirredução , Benzamidas/química
12.
Biomacromolecules ; 25(3): 1709-1723, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38377481

RESUMO

Polysaccharide nanoporous structures are suitable for various applications, ranging from biomedical scaffolds to adsorption materials, owing to their biocompatibility and large surface areas. Pectin, in particular, can create 3D nanoporous structures in aqueous solutions by binding with calcium cations and creating nanopores by phase separation; this process involves forming hydrogen bonds between alcohols and pectin chains in water and alcohol mixtures and the resulting penetration of alcohols into calcium-bound pectin gels. However, owing to the dehydration and condensation of polysaccharide chains during drying, it has proven to be challenging to maintain the 3D nanoporous structure without using a freeze-drying process or supercritical fluid. Herein, we report a facile method for creating polysaccharide-based xerogels, involving the co-evaporation of water with a nonsolvent (e.g., a low-molecular-weight hydrophobic alcohol such as isopropyl or n-propyl alcohol) at ambient conditions. Experiments and coarse-grained molecular dynamics simulations confirmed that salt-induced phase separation and hydrogen bonding between hydrophobic alcohols and pectin chains were the dominant processes in mixtures of pectin, water, and hydrophobic alcohols. Furthermore, the azeotropic evaporation of water and alcohol mixed in approximately 1:1 molar ratios was maintained during the natural drying process under ambient conditions, preventing the hydration and aggregation of the hydrophilic pectin chains. These results introduce a simple and convenient process to produce 3D polysaccharide xerogels under ambient conditions.


Assuntos
Cálcio , Nanoporos , Cálcio/química , Pectinas/química , Água/química , Cloreto de Sódio , Álcoois/química
13.
J Agric Food Chem ; 72(10): 5439-5451, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38412221

RESUMO

Increasing hydrogen peroxide (H2O2)-based systems have been developed to degrade various polysaccharides due to the presence of highly reactive free radicals, but published degradation mechanisms are still limited. Therefore, this study aimed to clarify the degradation mechanism of six typical glucosidic bonds from different disaccharides in an ultraviolet (UV)/H2O2 system. The results showed that the H2O2 concentration, disaccharide concentration, and radiation intensity were important factors affecting pseudo-first-order kinetic constants. Hydroxyl radical, superoxide radical, and UV alone contributed 58.37, 18.52, and 19.17% to degradation, respectively. The apparent degradation rates ranked in the order of cellobiose ≈ lactose > trehalose ≈ isomaltose > turanose > sucrose ≈ maltose. The reaction pathways were then deduced after identifying their degradation products. According to quantum chemical calculations, the cleavage of α-glycosidic bonds was more kinetically unfavorable than that of ß-glycosidic bonds. Additionally, the order of apparent degradation rates depended on the energy barriers for the formation of disaccharide-based alkoxyl radicals. Moreover, energy barriers for homolytic scissions of glucosidic C1-O or C7-O sites of these alkoxyl radicals ranked in the sequence: α-(1 → 2) ≈ α-(1 → 3) < α-(1 → 4) < ß-(1 → 4) < α-(1 → 6) < α-(1 → 1) glucosidic bonds. This study helps to explain the mechanisms of carbohydrate degradation by free radicals.


Assuntos
Álcoois , Peróxido de Hidrogênio , Poluentes Químicos da Água , Peróxido de Hidrogênio/química , Glucosídeos , Dissacarídeos/química , Maltose/metabolismo , Sacarose/química , Raios Ultravioleta , Oxirredução , Cinética , Poluentes Químicos da Água/química
14.
Chem Pharm Bull (Tokyo) ; 72(2): 213-219, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38382974

RESUMO

Nucleophilic deprotection of p-methoxybenzyl (PMB) [p-methoxyphenylmethyl (MPM)] ethers was developed using a heterogeneous oxovanadium catalyst V-MPS4 and a thiol nucleophile. The deprotection method had a wide reaction scope, including PMB ethers of primary, secondary, and tertiary alcohols bearing various functional groups. In addition, the PMB ether of an oxidation-labile natural product was successfully removed by V-MPS4 catalysis, while a common oxidative method of PMB deprotection afforded a complex mixture. The V-MPS4 catalyst was reusable up to six times without a significant loss in the product yield. The advantages of using the heterogeneous catalyst were further demonstrated by conducting the deprotection reaction in a continuous flow process, which resulted in a 2.7-fold higher catalyst turnover number and 60-fold higher turnover frequency compared to those of the corresponding batch reaction.


Assuntos
Éteres , Etil-Éteres , Catálise , Álcoois , Oxirredução
15.
Nature ; 628(8006): 104-109, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38350601

RESUMO

The development of bimolecular homolytic substitution (SH2) catalysis has expanded cross-coupling chemistries by enabling the selective combination of any primary radical with any secondary or tertiary radical through a radical sorting mechanism1-8. Biomimetic9,10 SH2 catalysis can be used to merge common feedstock chemicals-such as alcohols, acids and halides-in various permutations for the construction of a single C(sp3)-C(sp3) bond. The ability to sort these two distinct radicals across commercially available alkenes in a three-component manner would enable the simultaneous construction of two C(sp3)-C(sp3) bonds, greatly accelerating access to complex molecules and drug-like chemical space11. However, the simultaneous in situ formation of electrophilic and primary nucleophilic radicals in the presence of unactivated alkenes is problematic, typically leading to statistical radical recombination, hydrogen atom transfer, disproportionation and other deleterious pathways12,13. Here we report the use of bimolecular homolytic substitution catalysis to sort an electrophilic radical and a nucleophilic radical across an unactivated alkene. This reaction involves the in situ formation of three distinct radical species, which are then differentiated by size and electronics, allowing for regioselective formation of the desired dialkylated products. This work accelerates access to pharmaceutically relevant C(sp3)-rich molecules and defines a distinct mechanistic approach for alkene dialkylation.


Assuntos
Alcenos , Catálise , Hidrogênio , Ácidos/química , Álcoois/química , Alcenos/química , Biomimética , Hidrogênio/química , Preparações Farmacêuticas/síntese química , Preparações Farmacêuticas/química
16.
J Oleo Sci ; 73(2): 253-261, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38311414

RESUMO

New troponoid liquid crystals with 5-(4-alkoxyphenylethynyl)tropolone cores were synthesized. The 5-(4-alkoxyphenylethynyl)tropolones were obtained by the palladium-catalyzed cross-coupling of 5-iodotropolone with 4-alkoxyphenylacetylenes. The 2-alkoxy-5-(4-alkoxyphenylethynyl)tropones (1A) showed enantiotropic smectic phases, such as smectic A, C, and B. The 2-(4-alkoxy)benzoyloxy-5-(4-alkoxyphenylethynyl)tropones (1B) had enantiotropic nematic and smectic C phases. The 2-alkoxytropone derivatives (1A) had higher clearing temperatures and lower melting points than the corresponding benzene derivatives (2A). However, the 2-(4-alkoxybenzoyl)tropone derivatives (1B) had lower clearing temperatures and higher melting points than the corresponding benzene derivatives (2B).


Assuntos
Álcoois , Cristais Líquidos , Tropolona , Cristais Líquidos/química , Temperatura , Derivados de Benzeno
17.
Carbohydr Res ; 536: 109044, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38325068

RESUMO

Stereocontrolled synthesis of rare sugar derivatives, namely α-d-allulofuranosides, was achieved using d-fructose, one of the most abundant carbohydrates in nature. The following are the key steps of the α-d-allulofuranosides' synthesis. (1) An α-selective glycosidation reaction of 1,3,4,6-tetra-O-benzoylated d-fructofuranosyl donor to obtain α-d-fructofuranosides with 98 %-75 % isolated yields. (2) A regioselective 1,4,6-tri-O-pivaloylation reaction of the tetraol of α-d-fructofuranosides with the C3-hydroxy group remaining intact. (3) The oxidation of the C3-hydroxy group followed by the stereoselective reduction of the C3-carbonyl group. Primary and secondary alcohols and sugars can be used as glycosyl acceptors and aglycones for the following pivaloylation and stereoinversion reactions to obtain α-d-allulofuranosides.


Assuntos
Álcoois , Carboidratos , Oxirredução
18.
Food Res Int ; 177: 113919, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38225120

RESUMO

Highland barley vinegar, as a solid-state fermentation-type vinegar emerged recently, is well-known in Qinghai-Tibet plateau area of China. This work aimed to explore the main physicochemical factors, key flavor volatile compounds, and dominate microorganisms of highland barley vinegar during fermentation. The results showed that the decrease trend of reducing sugar, pH and the increase trend of amino acid nitrogen were associated with the metabolism of dominate bacteria, especially Lactobacillus and Acetobacter. Totally, 35 volatile compounds mainly including 20 esters, 10 alcohols, 2 aldehydes, 1 ketone and 2 pyrazines and 7 organic acids were identified. Especially, isoamyl acetate, acetyl methyl carbinol, ethyl caprylate, 1,2-propanediol, 3-methyl-1-butanol and ethyl isovalerate with high odor activity values were confirmed as key aroma compounds. Meanwhile, the relative average abundance of bacteria at genus level decreased significantly as fermentation time goes on. Among these microbes, Lactobacillus were the dominate bacteria at alcohol fermentation stage, Lactobacillus and Acetobacter were dominate at acetic acid fermentation stage. Furthermore, the correlations between dominate bacteria and the key volatile compounds were revealed, which highlighted Lactobacillus and Acetobacter were significantly correlated with key volatile compounds (|r| > 0.5, P < 0.01). The fundings of this study provide insights into the flavor and assist to improve the production quality of highland barley vinegar.


Assuntos
Acetobacter , Hordeum , Ácido Acético/metabolismo , Fermentação , Álcoois/metabolismo , Bactérias/metabolismo , Acetobacter/metabolismo
19.
Curr Opin Biotechnol ; 85: 103063, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219523

RESUMO

Medium-chain fatty alcohols (mcFaOHs) are aliphatic primary alcohols containing six to twelve carbons that are widely used in materials, pharmaceuticals, and cosmetics. Microbial biosynthesis has been touted as a route to less-abundant chain-length molecules and as a sustainable alternative to current petrochemical processes. Several metabolic engineering strategies for producing mcFaOHs have been demonstrated in the literature, yet processes continue to suffer from poor selectivity and mcFaOH toxicity, leading to reduced titers, rates, and yields of the desired compounds. This opinion examines the current state of microbial mcFaOH biosynthesis, summarizing engineering efforts to tailor selectivity and improve product tolerance by implementing engineering strategies that circumvent or overcome mcFaOH toxicity.


Assuntos
Álcoois , Álcoois Graxos , Álcoois Graxos/metabolismo , Engenharia Metabólica , Ácidos Graxos/metabolismo
20.
Chem Biodivers ; 21(3): e202301795, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38268034

RESUMO

This work reports the first example of employing ester-functionalized pillar[5]arene (P5A-C10-OAc) stationary phase for gas chromatography (GC) separations. The as-fabricated P5A-C10-OAc column achieved improved column efficiency of 4270 plates/m and separation performance in contrast to the P5-C10-Br column. The P5A-C10-OAc column showed good separation performance for a wide range of analytes such as alkanes, bromoalkanes, ketones, fatty acid methyl esters, aldehydes, alcohols, halobenzenes, anilines, phenols, naphthalenes, and showed sharp and symmetrical peak shapes for analytes that are liable to peak-tailing in GC analysis. As testified by the challenging isomer mixtures (bromonitrobenzene, chloronitrobenzene, bromobenzaldehyde, chlorobenzaldehyde, nitrobenzaldehyde), the P5A-C10-OAc column exhibited comprehensively higher separation capability than the P5A-C10-Br, P5A-C10 and commercial HP-35 columns. This work demonstrates the great potential of pillararene-based stationary phases as a new type of stationary phases for GC separations.


Assuntos
Álcoois , Compostos de Anilina , Reprodutibilidade dos Testes , Cromatografia Gasosa/métodos , Compostos de Anilina/química , Isomerismo
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