Ester Compounds Research Articles

A COMPREHENSIVE ANALYSIS OF THE CHEMICAL PROFILE OF VOLATILE COMPOUNDS IN NARCISSUS TAZETTA L. SUBSP. TAZETTA THROUGH HIERARCHICAL CLUSTERING METHODS

Objective: This study aimed to analyze the chemical profile of volatile and non-volatile components of Narcissus tazetta subsp. tazetta (daffodil) is grown in Türkiye. The chemical profiles of fresh and dried flowers were analyzed using Headspace Solid-Phase Microextraction (HS-SPME) and Gas Chromatography-Mass Spectrometry (GC-MS) methods. The study also aimed to investigate the effects of the drying process on the chemical profile and contribute to the plant's pharmacological, commercial, and ecological potential. Material and Method: Fresh and dried flower samples collected from the Muğla region were analyzed using the HS-SPME method. Fresh samples were immediately analyzed to prevent the loss of volatile compounds, while dried samples were air-dried at room temperature until they reached a constant weight and stored at 4°C. The mass spectra of volatile compounds were evaluated using GC/MS in conjunction with the Başer Library and other reference databases. Hierarchical Cluster Analysis (HCA) was applied for statistical analysis and clustering. Result and Discussion: The main volatile compounds identified in fresh flowers were (E)-β-ocimene (62.8%), 1,8-cineole (12.9%), and linalool (7.6%). In dried flowers, (E)-β-ocimene (43.1%), (Z)-3-hexenal (18.7%), and (Z)-3-hexenyl acetate (9.8%) were prominent. Significant changes were observed in volatile compounds after drying, with monoterpene hydrocarbons decreasing and new aldehyde and ester compounds emerging. The influence of regional and environmental factors on the chemical profile was emphasized. The Muğla samples showed differences compared to samples from İzmir, Siirt, and Şırnak. HCA successfully grouped the compounds based on structural and functional similarities, statistically highlighting the chemical differences between fresh and dried flowers.

Fabrication of highly durable flame-retardant silk textiles by depositing phosphorus/nitrogen compounds.

Fabrication of highly durable flame-retardant silk textiles by depositing phosphorus/nitrogen compounds.

Metal sulfides in aged-coarse sands tailings facilitate naphthenic acids removal from oil sands process water.

Metal sulfides in aged-coarse sands tailings facilitate naphthenic acids removal from oil sands process water.

Cross-Metathesis Coupling for Access to Some New α,β-Unsaturated Esters Derived from 2-Mercaptobenzoxazole

This study involves the synthesis of eight α,β-unsaturated ester compounds, obtained from 2-mercaptobenzoxazoles 3-10 by a two-step reaction. The first step included S-allylation of 2-mercaptobenzoxazole (1) with allyl bromide to furnish 2-(allylthio)benzo[d]oxazole (2) in a good yield (71%). The second step involved a cross-metathesis reaction of compound 2 with acrylate esters, which afforded the title products 3-10 in yields between 70 and 86%. The structure of the prepared compounds (2-10) was confirmed by FT-IR, 1H NMR, and 13C NMR spectroscopy.

Influence of Enzymatic Acylation on the Stability and Antioxidant Properties of Cyanidin-3-O-Glucoside in Both Aqueous and Lipid Systems.

Cyanidin-3-O-glucoside (C3G) was used as a substrate for enzymatic acylation, and different compounds (methyl n-octanoate and methyl salicylate) were selected as acyl donors. Structural analysis (UV-Vis, FTIR, and HPLC) revealed the successful integration of methyl ester compounds into the structural units of C3G. The thermostability and photostability of acylated C3Gs, particularly those with methyl salicylate as the acyl donor, exhibited significant improvements. The molecular geometries of the different anthocyanins were optimized using computational chemistry, and energy level calculations were performed by using Density Functional Theory (DFT) to identify the antioxidant active site. Then, the antioxidant properties of C3G and acylated C3Gs (O-C3G and S-C3G) were studied in both aqueous and lipid systems. In aqueous systems, acylated C3Gs exhibited higher antioxidant properties than C3G in DPPH radical scavenging and hydroxyl radical scavenging assays, with cyanidin-3-O-glucoside salicyl acyl product (S-C3G) demonstrating the highest activity. However, the antioxidant properties varied in lipid systems. In lipid systems, acylated C3Gs displayed better antioxidant properties than C3G in POV and TBARS assays, with cyanidin-3-O-glucoside n-octanoate acid acyl product (O-C3G) showing better antioxidant properties compared to that in aqueous systems.

Comprehensive analysis of volatile flavor components in pear fruit spanning the entire development stages.

Comprehensive analysis of volatile flavor components in pear fruit spanning the entire development stages.

The influence of organic acids on the dynamic perception of trigeminal pungency induced by ethanol and ester compounds

The influence of organic acids on the dynamic perception of trigeminal pungency induced by ethanol and ester compounds

Identification of a phenyl ester covalent inhibitor of caseinolytic protease and analysis of the ClpP1P2 inhibition in mycobacteria

AbstractThe caseinolytic protease complex ClpP1P2 is crucial for protein homeostasis in mycobacteria and stress response and virulence of the pathogens. Its role as a potential drug target for combating tuberculosis (TB) has just begun to be substantiated in drug discovery research. We conducted a biochemical screening targeting the ClpP1P2 using a library of compounds phenotypically active against Mycobacterium tuberculosis (Mtb). The screening identified a phenyl ester compound GDI‐5755, inhibiting the growth of Mtb and M. bovis BCG, the model organism of mycobacteria. GDI‐5755 covalently modified the active‐site serine residue of ClpP1, rendering the peptidase inactive, which was delineated through protein mass spectrometry and kinetic analyses. GDI‐5755 exerted antibacterial activity by inhibiting ClpP1P2 in the bacteria, which could be demonstrated through a minimum inhibitory concentration (MIC) shift assay with a clpP1 CRISPRi knockdown (clpP1‐KD) mutant GH189. The knockdown also remarkably heightened the mutant's sensitivity to ethionamide and meropenem, but not to many other TB drugs. On the other hand, a comparative proteomic analysis of wild‐type cells exposed to GDI‐5755 revealed the dysregulated proteome, specifically showing changes in the expression levels of multiple TB drug targets, including EthA, LdtMt2, and PanD. Subsequent evaluation confirmed the synergistic activity of GDI‐5755 when combined with the TB drugs to inhibit mycobacterial growth. Our findings indicate that small‐molecule inhibitors targeting ClpP1P2, when used alongside existing TB medications, could represent novel therapeutic strategies.

Production, characterization and antioxidant analysis on the Undaria-based alcoholic beverages using response surface method and HS-SPME-GC×GC-TOF-MS.

Production, characterization and antioxidant analysis on the Undaria-based alcoholic beverages using response surface method and HS-SPME-GC×GC-TOF-MS.

A novel electrochemical sensor for detection of cysteine based on a Methacrylic Ester compound probe

A novel electrochemical sensor for detection of cysteine based on a Methacrylic Ester compound probe

Plant Tannase: Evolutionary and Functional Divergence Features.

In plants, α/β-hydrolase regulates the hydrolysis of ester compounds, enriching the types and functions of specialized metabolites. In this study, three genes─CsCSE, CsCXE3, and CsTA─which encode caffeoyl shikimate esterase (CSE), carboxylesterase (CXE), and tannase (TA), respectively, were isolated from the tea plant genome through multiomics correlation analysis. Evolutionary analysis showed that CSE and CXE were ancient, whereas TA emerged in core eudicots approximately 120 million years ago. Enzyme activity assays revealed that CsCSE and CsCXE3 catalyze phenolic acid and acetate ester hydrolysis, respectively. Interestingly, CsTA not only has the catalytic function of CsCSE and CsCXE3 but also catalyzes the hydrolysis of galloylated catechin, hydrolyzable tannin, and hormone ester. Overall, CsTA is a newly derived α/β-hydrolase with evolutionary and functional divergence features. This study expands our understanding of the physiological significance of plant TA and provides insights into the potential role of CsTA in the complex metabolic processes of tea plants.

Impact of Pulsed Electric Fields Combined with Dissolved Oxygen and Ferrous Ions on the Aroma and Components of Strong-Flavor Baijiu.

This research examined the influences of electric field strength and pulse frequency of pulsed electric field (PEF) treatment, along with the combined effects of dissolved oxygen and ferrous iron ions on the aroma and components of strong-flavor baijiu. PEF treatment improved fruity aromas and decreased the pit mud odor. Electric field strength promoted the production of short-chain fatty acid esters, while pulse frequency facilitated the formation of acetal oxidation products. The most notable changes were observed at an electric field strength of 25 kV, and a pulse frequency of 350 Hz. Increasing dissolved oxygen significantly improves fruity and mellow aromas and promotes the generation of 17 compounds including ethyl lactate, ethyl butyrate, hexan-1-ol, octanoic acid, and 3-methylbutanal, while Fe2⁺ treatment reduces the fruity aroma of baijiu and significantly suppresses the production of 15 esters including ethyl hexanoate, hexyl hexanoate, and ethyl lactate. Dissolved oxygen may contribute to the generation of hydroxyl radicals and regulated oxidation reactions partially in baijiu. And, Fe2+ may react with organic acids to promote the hydrolysis of ester compounds. This study aims to offer valuable insights into the practical application of PEF in the flavor regulation of baijiu.

Synthesis and In Vitro Profiling of Psilocin Derivatives: Improved Stability and Synthetic Properties.

As interest in using psilocybin therapy for treating mental health disorders intensifies, the need for efficient production methods becomes increasingly important. Current medical-grade psilocybin production is inefficient and relies on a complicated multistep synthesis. This study has explored and evaluated psilocin ester prodrugs and psilocin salts as potential alternatives to psilocybin, focusing on their ease of synthesis, chemical stability, and metabolic profiles. A diverse library of 15 psilocin ester prodrugs and six psilocin salts was synthesized and evaluated. The study successfully identified several psilocin ester prodrugs and psilocin salts that exhibited desirable characteristics, including storage and handling stability, rapid metabolic conversion to psilocin, and easy synthesis, with potential advantages over psilocybin. This research introduces viable options through psilocin ester compounds and psilocin salts, offering promising avenues for future development.

Unraveling the multiple interactions between phages, microbes and flavor in the fermentation of strong-flavor Baijiu

The fermentation process of strong-flavor Baijiu represents a complex and unique ecosystem, characterized by the involvement of various microorganisms that drive intricate biochemical reactions, ultimately contributing to the distinct flavor profile of the Baijiu. Viruses may affect the succession of microorganisms and thus affect the style and quality of the product. However, the interaction between viruses and microorganisms during the fermentation of Baijiu is still unclear. Here we combined viral metagenomics and amplicon sequencing, physicochemical analysis, and GC–MS detection with temporal sampling to study the dynamics of viral and microbial communities, physicochemical properties, and flavor compounds during strong-flavor Baijiu fermentation. Viral metagenomic analysis revealed 513 viral operational taxonomic units (vOTUs), encompassing 34 viral families. Principal coordinates analysis (PCoA) demonstrated significant differences in vOTUs at different fermentation stages. Notably, the microbial community exhibited distinct succession patterns at various fermentation stages; it changed rapidly during the initial five days, with similarities observed between days 10 and 20. Volatile profile analysis identified 38 flavor components in fermented grains, comprising 16 ester compounds, 11 alcohols, and 8 acids, with the majority formed between days 10 and 30. The Spearman's rank correlation analysis revealed that Peduoviridae exhibited a negative correlation with Gluconobacter. Genomoviridae showed a negative correlation with Issatchenkia, Penicillium, and Monascus. These findings highlight the potential for complex interactions between viruses and microbial communities during Baijiu fermentation, underscoring the importance of considering viral communities in studies of the microbial ecology of fermented foods.Graphical

Long-term frozen storage affects the volatile compound profile, physicochemical and antioxidant content of vacuum-packed Musang King durian fruit.

Musang King (MK) durian is a valued Malaysian fruit, marketed at full ripeness for its characteristic sensory profile but has a short shelf life. Frozen storage and vacuum packaging extend its shelf life, yet their effect on quality remains unclear. This study investigated the impact of vacuum packaging on the volatile compounds (VOCs), physicochemical characteristics, and antioxidant content of MK durian fruits stored for 12 months at -20°C using biochemical and physiochemical approaches. Results showed that vacuum packaging and storage duration affect the MK durian VOC profiles. Twenty-seven VOCs were affected by both packaging condition and storage durations and identified as key VOC markers for MK durian storage stability and quality. Ester compounds were significantly reduced by vacuum packaging, while sulfur compounds exhibited a higher steady increase in non-vacuum-packed durian compared to vacuum-packed durian during storage. Additionally, vacuum packaging resulted in higher reducing sugars, b* values, and antioxidant content compared to non-vacuum packaging during fruit storage. In short, vacuum packaging better retains the post-harvest quality of MK durian fruit during long-term frozen storage than non-vacuum packaging.

Differentiation of white rice Khao Dawk Mali 105 (KDML105) from other Thai white rice using FTIR microscope-attenuated total reflectance-focal plane array detector

Thai Hom Mali rice is one of Thailand’s most important agricultural products, due to its higher commercial value compared to other rice, both domestically and internationally. A higher ratio of other white rice varieties is frequently found in white rice Thai Hom Mali affects consumer confidence since there is no fast procedure for differentiation of Thai Hom Mali Rice from other rice varieties, for this reason, this research proposed a spectroscopic analysis method to investigate the biochemical content of rice samples for distinguishing Thai Hom Mali Rice from other rice varieties. The absorbance spectrum of five Thai rice varieties was identified: Khao Dawk Mali 105 (KDML105), Pathum Thani 1 (PTT1), RD77, Chai Nat 1 (CN1), and Phitsanulok 2 (PLS2). The FTIR-microscopeattenuated total reflectance-focal plane array detector (FTIR-microscope-ATR-FPA detector) was applied to acquire the bandwidth of the mid-wavelength infrared (3800-900 cm-1 ). According to the spectroscopic data, the absorbance spectrum of KDML105 rice contained a strong intensity to identify the wavenumber at 1250 and 1748 cm-1 representing the vibrational mode of C–N stretching in aromatic amine and C=O stretch in ester compounds, respectively. The rice varieties were classified using principal component analysis (PCA) to identify the wavenumber and separate the KDML105 rice from other rice varieties with PC1 achieving more than 82% for individual analysis and more than 40% for overall analysis, respectively.

Adjustability and Versatility of Molecular Packing Patterns in Asymmetric Coumarin Liquid Crystals Supramolecular Helical Column Structures.

Coumarin asymmetric multi-chain liquid crystals (LCs) were synthesized using click reaction, with coumarin core and 1,2,3-triazole dendritic wings on both sides. The properties of these LCs and the resulting gels were investigated using polarized optical microscopy (POM), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning electron microscopy (SEM). These polycatenars demonstrate the ability to self-assemble into columnar LCs phases, exhibiting p4 mm symmetry in their bulk states. In DMF solvent, ether compounds yield gels with notably more ordered, spherical flower-like morphologies, while ester compounds produce gels that are less ordered and exhibit a nanosphere morphology. The findings indicate that the polarities of both the linkages and the solvents play a critical role in the formation of supramolecular nanostructures. Interestingly, the 2 was proved as promising imaging probe for latent fingerprints (LFPs) and fluorescent fingerprints images were obtained with high-resolution, which showed potential practical application for LFPs detection. Additionally, LCs compounds are used as dopants to modify the poly(3,4-ethylenedioxythiophene):polystyrene (PEDOT:PSS) injection layer of Organic silicone-based heterojunction solar cells (HSCs). Finally, Density functional theory (DFT) calculations are performed to theoretically study such as geometric structure, frontier molecular orbitals, molecular electrostatic potential, and dipole moment.

Genome-Wide Identification Analysis of the 4-Coumarate: Coa Ligase (4CL) Gene Family in Brassica U's Triangle Species and Its Potential Role in the Accumulation of Flavonoids in Brassica napus L.

4-Coumarate: CoA ligase (4CL) is a key branch point enzyme at the end of the phenylpropanoid metabolic pathway. It regulates the synthesis of various metabolites and participates in plant growth and development by catalyzing the formation of CoA ester compounds. However, 4CL family members have not been identified and analyzed among U's triangle species in Brassica. In this study, 53 4CL genes were identified in Brassica U's triangle species and divided into 4 groups (group I, II, III and IV) according to phylogenetic relationship. Based on phylogenetics, gene structure, conserved motifs, chromosome localization and collinearity analysis, 4CLs were relatively conserved in the evolution of Brassica U's triangle species. The promoter region contains a large number of cis-acting elements, implying the functional diversity of 4CLs. Further combining transcriptome data and reverse transcription quantitative PCR (RT-qPCR), we found that Bna4CLs have tissue specificity and can not only respond to exogenous phytohormone changes but also regulate the flavonoid biosynthetic pathway in the yellow- and black-seeded B. napus. Our results complement the lack of research on the 4CL gene family in Brassica, clarify the sequence characteristics and functional diversity of these genes and lay a foundation for further exploration of 4CL genes in response to abiotic stress and regulation of seed coat flavonoid accumulation.

Phytochemical and antibacterial properties of calyces Hibiscus sabdariffa L.: an in vitro and in silico multitarget-mediated antibacterial study

BackgroundMultidrug-resistant (MDR) bacteria pose a significant threat to human health worldwide by increasing the harmful impact of traditional synthetic antibiotics. Traditional medicinal plants have bioactive metabolites that can significantly modulate the growth rate, cell survival, and pathogenicity of antibiotic-resistant bacteria. Hibiscus sabdariffa L., known as Roselle or Karkade, belongs to the Malvaceae family. It is well-known for its edible aromatic red/purple calyces and is extensively utilized in the food industry and pharmacological applications. H. sabdariffa calyx bioactive phytocompounds have potent therapeutic activities such as antimicrobial, antidiabetic, antiobesity, antioxidant, anti-inflammatory, and anticancer properties.MethodsThis study utilized gas chromatography-mass spectrometry (GC-MS) analysis to determine the volatile aromatic compounds that found in the hydroethanolic extract of Hibiscus sabdariffa calyces. The purpose was to verify the antibacterial properties of Roselle calyces against selective MDR clinical bacterial isolates, including A. baumanii, E. coli, K. pneumoniae, and P. aeruginosa.ResultsThe GC-MS spectrum profile revealed the presence of twenty-seven volatile organic components, including organic fatty acid derivatives, ester compounds, sugar derivatives, and terpene components. The major GC-MS fractionations and the main active chemical compositions of the hydroethanolic extract of H. sabdariffa flowers were (E)-10-Octadecenoic acid methyl ester (59.23%), 8,11-Octadecadienoic acid, methyl ester (11.51%), Butanedioic acid, 3-hydroxy-2,2-dimethyl-, diethyl ester (6.22%), Diethyl succinate/Butanedioic acid, diethyl ester (2.35%), and Heptadecanoic acid, 16-methyl-, methyl ester/Methyl isostearate (2.31%). The hydroethanolic extract of H. sabdariffa dried calyces demonstrated potent antibacterial properties (zones diameter of inhibition growth, MIC, MBC, and MBC/MIC) against selective MDR clinical bacterial isolates, such as A. baumanii, E. coli, K. pneumoniae, and P. aeruginosa, as determined by the phytochemical screening (TAC, TFC, and TPC) and antioxidant activity (DPPH). The surface morphological characteristics of the treated A. baumanii, E. coli, K. pneumoniae, and P. aeruginosa clinical isolates have been affected in comparison to the untreated forms by the hydroethanolic extract of H. sabdariffa calyces, as determined by scanning electron microscopy (SEM). In silico predictive investigation revealed that the volatile aromatic components of the hydroethanolic extract of Roselle calyces exhibited significant scoring functions, binding affinities, and non-covalent intermolecular interactions with the MenB lyase and DNA gyrase targets of E. coli. These interactions significantly enhanced the activities of the volatile aromatic components against the bacterial pathogenicity, cell survival, growth, and differentiation of selective MDR clinical bacterial isolates.ConclusionsAccording to the in vitro and in silico findings, the hydroethanolic extract of H. sabdariffa calyces has shown potentials as an effective antioxidant and antibacterial treatment. It contains volatile aromatic compounds that can modulate selective MDR Gram-negative clinical bacterial isolates.

Synthesis and Optoelectronic Properties of Perylene Diimide-Based Liquid Crystals.

Perylene diimide (PDI), initially synthesized and explored as an organic dye, has since gained significant recognition for its outstanding optical and electronic properties. Early research primarily focused on its vibrant coloration; however, the resolution of solubility challenges has revealed its broader potential. PDIs exhibit exceptional optical characteristics, including strong absorption and high fluorescence quantum yield, along with remarkable electronic properties, such as high electron affinity and superior charge carrier mobility. Furthermore, the robust π-π stacking interactions and liquid crystalline behavior of PDIs facilitate precise their self-assembly into highly ordered structures, positioning them as valuable materials for advanced applications in optoelectronics, photonics, and nanotechnology. This article provides a comprehensive review of the progress made in the design, synthesis, and optoelectronic performance of PDI-based liquid crystals. It explores how various substituents and their placement on the PDI core impact the properties of these liquid crystal molecules and discusses the challenges and opportunities that shape this rapidly evolving class of optical materials. This review is strictly focused on PDIs and does not cover their elongated or laterally extended derivatives, nor does it include monoimide or ester compounds.