Tag: M.W=100-150

Cordero, Chiara published the artcileOdorants quantitation in high-quality cocoa by multiple headspace solid phase micro-extraction: Adoption of FID-predicted response factors to extend method capabilities and information potential, Recommanded Product: 2,3,5-Trimethylpyrazine, the main research area is cocoa aroma headspace solid microextraction gas chromatog FID MS; Gas chromatography with parallel detection by MS and FID; High-quality cocoa; Key aroma compounds; Multiple headspace solid phase micro-extraction; Predicted FID relative response factors.

This paper focuses on several methodol. aspects in the quantitation of volatiles in solid samples by headspace solid phase micro-extraction (HS-SPME) combined with gas chromatog. and parallel detection by flame ionization detector and mass spectrometry (GC-FID/MS). Informative volatiles, including key odorants and process markers, from single-origin cocoa samples (Colombia, Ecuador, Mexico, Sao Tome and Venezuela) were captured at two processing stages along the chocolate production chain (nibs and cocoa mass). Accurate quantitation was achieved by multiple headspace extraction (MHE) in headspace linearity conditions and by external calibration. Quant. results on selected analytes (3-hydroxy-2-butanone, 2-heptanol, 2,3,5-trimethylpyrazine, 2-ethyl-3,6-dimethylpyrazine, Et octanoate, benzaldehyde, 2-methylpropionic acid, 3-methylbutyric acid, Et phenylacetate, 2-phenylethyl acetate, guaiacol, 2-phenylethanol, and (E)-2-phenyl-2-butenal) provided reliable information about the key sensory notes of cocoa intermediates (odor activity values) and their origin specificities. Addnl. information about analytes release by the solid environment (cocoa nibs, mass, and powders) was achieved by modeling decay curves. Parallel detection by MS and FID enabled quant. cross-validation, and FID-predicted relative response factors (RRFs) extended method quantitation capabilities to addnl. compounds that were not subjected to an external calibration procedure: 3-methylbutyl acetate (isoamyl acetate), 2-heptanone, heptanal, 2-nonanone, γ-butyrolactone, octanoic acid, 2-ethyl-5(6)-methylpyrazine, phenylacetic acid, phenol, 2-acetyl pyrrole, and 2,3-dihydro-3,5-dihydroxy-6-methyl(4H)-pyran-4-one. This procedure extends method capabilities and information potential with great consistency.

Analytica Chimica Acta published new progress about Chocolate. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Recommanded Product: 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Farmany, Abbas published the artcileInformatics aided QSRR study of retention index of some volatile compounds, Synthetic Route of 14667-55-1, the main research area is volatile compound retention index QSRR study.

In the present work, an artificial neural network (ANN) model was used to study the quant. structure retention relationship (QSRR) of retention index (RI) of some volatile compounds in natural cocoa and conched chocolate powder. Mol. structural descriptors are selected using genetic algorithm to construct the nonlinear QSRR models. Besides, kernel partial least squares PLS (KPLS) and Levenberg-Marquardt artificial neural network (L-M ANN) were employed.

Eurasian Chemical Communications published new progress about Chocolate. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Synthetic Route of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Porcelli, Caterina published the artcileMolecular background of a moldy-musty off-flavor in cocoa, HPLC of Formula: 14667-55-1, the main research area is moldy musty off flavor cocoa chocolate; (−)-geosmin; 3-methyl-1H-indole; aroma extract dilution analysis (AEDA); cocoa (Theobroma cacao L.); moldy-musty off-flavor; stable isotopically substituted odorants.

The parallel application of aroma extract dilution anal. to the volatiles isolated from a sample of fermented cocoa seeds with a pronounced moldy-musty off-flavor and to the volatiles isolated from a flawless reference sample revealed (-)-geosmin, 4-methoxy-2,5-dimethylfuran-3(2H)-one, 1H-indole, and 3-methyl-1H-indole as potential off-flavor compounds on the basis of their odor quality and higher flavor dilution factors in off-flavor cocoa than in the reference sample. Quantitation of the four compounds in nine off-flavor cocoa samples and calculation of odor activity values (ratio of the concentrations to the odor threshold values) suggested the crucial roles of (-)-geosmin and 3-methyl-1H-indole for the off-flavor. In the chocolate industry, their quantitation can be used to objectively assess the off-flavor at the level of incoming goods inspection. Because both compounds are inhomogeneously distributed between the testa and the embryo, sep. quantitation in the two parts of the seeds is required.

Journal of Agricultural and Food Chemistry published new progress about Chocolate. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, HPLC of Formula: 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Fontes de Oliveira, Luciana published the artcileCorrelating comprehensive two-dimensional gas chromatography volatile profiles of chocolate with sensory analysis, Quality Control of 14667-55-1, the main research area is two dimensional gas chromatog volatile profile chocolate sensory analysis.

The identification of key components relevant to sensory perception of quality from com. chocolate samples was accomplished after chemometric processing of GC x GC-MS (Comprehensive Two dimensional Gas Chromatog. with Mass Spectrometric Detection) profiles corresponding to HS-SPME (Headspace Solid Phase Microextraction) extracts of the samples. Descriptive sensory evaluation of samples was carried out using Optimized Descriptive Profile (ODP) procedures, where sensory attributes of 24 com. chocolate samples were used to classify them in two classes (low and high chocolate flavor). 2D Fisher Ratio anal. was applied to four-way chromatog. data tensors (1st dimension retention time 1tR x 2nd dimension retention time 2tR x m/z x sample), to identify the crucial areas on the chromatograms that resulted on ODP class separation on Principal Component Anal. (PCA) scores plot. Comparing the relevant sections of the chromatograms to the anal. of the corresponding mass spectra, it was possible to assess that most of the information regarding the sample main sensory attributes can be related to only 14 compounds (2,5-dimethylpyrazine, 2,6-dimethyl-4-heptanol, 1-octen-3-ol, trimethylpyrazine, β-pinene, o-cimene, 2-ethyl-3,5-dimethylpyrazine, tetramethylpyrazine, benzaldehyde, 1,3,5-trimethylbenzene, 6-methyl-5-hepten-2-one, limonene, benzeneethanol and 1,1-dimethylbutylbenzene) among the complex blend of volatiles found on these extremely complex samples.

BrJAC–Brazilian Journal of Analytical Chemistry published new progress about Chocolate. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Quality Control of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Yu, Jing published the artcileHalophilic bacteria as starter cultures: A new strategy to accelerate fermentation and enhance flavor of shrimp paste, COA of Formula: C7H10N2, the main research area is halophilic bacteria starter culture fermentation flavor shrimp paste; Fermentation; Halophilic bacteria; Sensory evaluation; Shrimp paste; Volatile compounds.

Retaining the traditional flavor while shortening the fermentation cycle is the current research focus for shrimp paste fermentation technol. The present study investigated the effect of combined use of halophilic bacteria as starters on the sensory and flavor characteristics of rapidly fermented shrimp paste. Sensory evaluation indicated that the starter-inoculated samples had high texture, appearance, and overall quality scores. Headspace gas chromatog.-ion mobility spectrometry/mass spectrometry (HS-GC-IMS/MS) identified 95 volatile compounds, the fingerprint profiles of the starter-inoculated samples were similar to those of the traditional sample. Notably, the content of benzaldehyde, phenylethylaldehyde, and 3-methylbutyraldehyde increased significantly in the starter-inoculated samples (p < 0.05), which may provide an intense malt, caramel, and pleasant odor. Although the content of certain flavor substances in the starter-inoculated samples was lower than those of traditional sample, the use significantly reduced the fermentation time and mimicked the flavor profile of traditional shrimp paste to some extent. Food Chemistry published new progress about Databases. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, COA of Formula: C7H10N2.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Sakkiah, Sugunadevi published the artcileDevelopment of a Nicotinic Acetylcholine Receptor nAChR α7 Binding Activity Prediction Model, Computed Properties of 14667-55-1, the main research area is nicotinic receptor binding addictive tobacco constituent.

Despite the well-known adverse health effects associated with tobacco use, addiction to nicotine found in tobacco products causes difficulty in quitting among users. Nicotinic acetylcholine receptors (nAChRs) are the physiol. targets of nicotine and facilitate addiction to tobacco products. The nAChR-α7 subtype plays an important role in addiction; therefore, predicting the binding activity of tobacco constituents to nAChR-α7 is an important component for assessing addictive potential of tobacco constituents. We developed an α7 binding activity prediction model based on a large training data set of 843 chems. with human α7 binding activity data extracted from PubChem and ChEMBL. The model was tested using 1215 chems. with rat α7 binding activity data from the same databases. Based on the competitive docking results, the docking scores were partitioned to the key residues that play important roles in the receptor-ligand binding. A decision forest was used to train the human α7 binding activity prediction model based on the partition of docking scores. Five-fold cross validations were conducted to estimate the performance of the decision forest models. The developed model was used to predict the potential human α7 binding activity for 5275 tobacco constituents. The human α7 binding activity data for 84 of the 5275 tobacco constituents were exptl. measured to confirm and empirically validate the prediction results. The prediction accuracy, sensitivity, and specificity were 64.3, 40.0, and 81.6%, resp. The developed prediction model of human α7 may be a useful tool for high-throughput screening of potential addictive tobacco constituents.

Journal of Chemical Information and Modeling published new progress about Databases. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Computed Properties of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Yao, Di published the artcileEffect of microbial communities on the quality characteristics of northeast soybean paste: Correlation between microorganisms and metabolites, Synthetic Route of 14667-55-1, the main research area is soybean paste microorganism metabolite microbial community.

To systematically explore the impact of microbial community composition on the quality characteristics of northeast soybean paste, the microbial community structure was determined by high-throughput sequencing technol. and the flavor substance, free amino acid (FAA) and biogenic amine (BA) contents were determined by HS-SPME-GC-MS and HPLC. Furthermore, the correlation between microorganisms and metabolites was investigated. The results indicated that the core bacteria mainly included Tetragenococcus, Bacillus and Lactobacillus; Candida_f__norank, Wickerhamomyces and Aspergillus were the dominant fungi. A total of 139 flavor compounds were detected in all samples, and decamethylcyclopentasiloxane, isoamyl phenylacetate and octamethylcyclotetrasiloxane accounted for the highest proportion. A total of 24 FAAs were detected in the soybean paste. Pantoea, Kroppenstedtia and Kocuria were significantly pos. correlated with most FAAs (p < 0.05). Addnl. 5 BAs were detected in the soybean paste, and the contents of BAs in Y4 were highest, which was affected by different microbes. This study provided relevant information for the microbial community composition and metabolites of northeast soybean paste, which was of great significance for understanding the characteristics and safety of soybean paste. LWT--Food Science and Technology published new progress about Acaulium. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Synthetic Route of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Shah, Niti H. published the artcileNon-targeted analysis using gas chromatography-mass spectrometry for evaluation of chemical composition of E-vapor products, Computed Properties of 14667-55-1, the main research area is E vapor product gas chromatog mass spectrometry chem composition; ENDS; GC-MS; aerosol; e-cigarettes; e-liquids; electronic vapor products; non-targeted analysis; semi-quantitative analysis.

The Premarket Tobacco Product Applications (PMTA) guidance issued by the Food and Drug Administration for electronic nicotine delivery systems (ENDSs) recommends that in addition to reporting harmful and potentially harmful constituents (HPHCs), manufacturers should evaluate these products for other chems. that could form during use and over time. Although e-vapor product aerosols are considerably less complex than mainstream smoke from cigarettes and heated tobacco product (HTP) aerosols, there are challenges with performing a comprehensive chem. characterization. Some of these challenges include the complexity of the e-liquid chem. compositions, the variety of flavors used, and the aerosol collection efficiency of volatile and semi-volatile compounds generated from aerosols. In this study, a non-targeted anal. method was developed using gas chromatog.-mass spectrometry (GC-MS) that allows evaluation of volatile and semi-volatile compounds in e-liquids and aerosols of e-vapor products. The method employed an automated data anal. workflow using Agilent MassHunter Unknowns Anal. software for mass spectral deconvolution, peak detection, and library searching and reporting. The automated process ensured data integrity and consistency of compound identification with >99% of known compounds being identified using an inhouse custom mass spectral library. The custom library was created to aid in compound identifications and includes over 1,100 unique mass spectral entries, of which 600 have been confirmed from reference standard comparisons. The method validation included accuracy, precision, repeatability, limit of detection (LOD), and selectivity. The validation also demonstrated that this semi-quant. method provides estimated concentrations with an accuracy ranging between 0.5- and 2.0-fold as compared to the actual values. The LOD threshold of 0.7 ppm was established based on instrument sensitivity and accuracy of the compounds identified. To demonstrate the application of this method, we share results from the comprehensive chem. profile of e-liquids and aerosols collected from a marketed e-vapor product. Applying the data processing workflow developed here, 46 compounds were detected in the e-liquid formulation and 55 compounds in the aerosol sample. More than 50% of compounds reported have been confirmed with reference standards The profiling approach described in this publication is applicable to evaluating volatile and semi-volatile compounds in e-vapor products.

Frontiers in Chemistry (Lausanne, Switzerland) published new progress about Aerosols. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Computed Properties of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Dandamudi, Kodanda Phani Raj published the artcileHydrothermal liquefaction of Cyanidioschyzon merolae and Salicornia bigelovii Torr.: The interaction effect on product distribution and chemistry, Product Details of C7H10N2, the main research area is hydrothermal liquefaction cyanidioschyzon merolae salicornia bigelovii Torr interaction effect.

Hydrothermal liquefaction (HTL) has proven to be a promising technol. for processing wet biomass into valuable biofuel intermediates. We investigated the influence of HTL process parameters on the individual and co-liquefaction of Salicornia bigelovii Torr. (SL) and Cyanidioschyzon merolae (CM) biomass and their resp. product properties and characteristics. SL and CM biomasses were subjected to HTL conditions of process temperatures (250-350 °C), 10 wt% solid loading, 30 min reaction time, and co-liquefaction ratios (80-20, 50-50, 20-80, CM-SL, resp.). The individual maximum HTL biocrude yields for CM (34.63 wt%) and SL (7.63 wt%) were obtained at 300 °C. In both cases, biocrude oils had a higher carbon and hydrogen content relative to those of the original biomass. The HHV (higher heating value) values for the biocrude samples ranged from 24.2 to 33.12 MJ/kg, which were significantly higher than those of the original biomasses. A pos. synergistic effect was observed during the co-liquefaction of two biomasses, where the exptl. yield of biocrude oil was higher than the theor. value. During the co-liquefaction experiments, a maximum biocrude yield of 32.95 wt% was obtained at 300 °C and 80-20 CM-SL biomass mix ratio. Co-liquefaction led to an increase in the energy content of the co-liquefied biocrude oil and a higher energy recovery rate. The properties of HTL products and biomasses were determined with TGA, CHN elemental analyzer, GC/MS, bomb calorimeter, HACH Spectrophotometer, and ICP OES.

Fuel published new progress about Biofuels. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Product Details of C7H10N2.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Cain, Caitlin N. published the artcileTile-Based Pairwise Analysis of GC x GC-TOFMS Data to Facilitate Analyte Discovery and Mass Spectrum Purification, Synthetic Route of 14667-55-1, the main research area is tile based pairwise GC TOFMS mass spectrum purification.

A new tile-based pairwise anal. workflow, termed 1v1 anal., is presented to discover and identify analytes that differentiate two chromatograms collected using comprehensive two-dimensional (2D) gas chromatog. coupled with time-of-flight mass spectrometry (GC x GC-TOFMS). Tile-based 1v1 anal. easily discovered all 18 non-native analytes spiked in diesel fuel within the top 30 hits, outperforming standard pairwise chromatog. analyses. However, eight spiked analytes could not be identified with multivariate curve resolution-alternating least-squares (MCR-ALS) nor parallel factor anal. (PARAFAC) due to background contamination. Analyte identification was achieved with class comparison enabled-mass spectrum purification (CCE-MSP), which obtains a pure analyte spectrum by normalizing the spectra to an interferent mass channel (m/z) identified from 1v1 anal. and subtracting the two spectra. This report also details the development of CCE-MSP assisted MCR-ALS, which removes the identified interferent m/z from the data prior to decomposition In total, 17 out of 18 spiked analytes had a match value (MV) > 800 with both versions of CCE-MSP. For example, MCR-ALS and PARAFAC were unable to decompose the pure spectrum of Me decanoate (MVs < 200) due to its low 2D chromatog. resolution (~0.34) and high interferent-to-analyte signal ratio (~30:1). By leveraging information gained from 1v1 anal., CCE-MSP and CCE-MSP assisted MCR-ALS obtained a pure spectrum with an average MV of 908 and 964, resp. Furthermore, tile-based 1v1 anal. was applied to track moisture damage in cacao beans, where 86 analytes with at least a 2-fold concentration change were discovered between the unmolded and molded samples. This 1v1 anal. workflow is beneficial for studies where multiple replicates are either unavailable or undesirable to save anal. time. Analytical Chemistry (Washington, DC, United States) published new progress about Cocoa beans. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Synthetic Route of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem