Month: November 2022

Birk, Florian published the artcileAroma active alkylated pyrazines are produced by Basfia succiniciproducens as by-products of succinic acid production, Synthetic Route of 14667-55-1, the main research area is Basfia succinic acid flavor dynamic headspace extraction.

Culture supernatants of Basfia succiniciproducens derived from the industrial production of succinic acid exhibit an intense nutty, root vegetable-like, buttery and sourish smell. By means of headspace-gas chromatog.-mass spectrometry-olfactometry (HS-GC-MS-O), 14 odor-active compounds were perceived and identified using two GC-columns of different polarity and comparison of retention indexes and mass spectra to those of authentic reference compounds Several alkylated pyrazines, including 2,3,5-trimethylpyrazine, 5-ethyl-2,3-dimethylpyrazine, 2,3,5,6-tetramethylpyrazine, 2,3,5-trimethyl-6-ethylpyrazine, 2,3,5-trimethyl-6-propylpyrazine and 2,3,5-trimethyl-6-butylpyrazine were found to contribute to the aroma of the culture supernatant. Quantitation of the pyrazines was performed by means of dynamic headspace-GC-MS after standard addition, and 2,3,5,6-tetramethylpyrazine (9.10 mg/L) was the most abundant compound Waste streams of the biotechnol. production of commodity chems. may thus represent a sustainable resource for the isolation of aroma compounds

Flavour and Fragrance Journal published new progress about Basfia succiniciproducens. 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

Diez-Quijada, Leticia published the artcileAlterations in Mediterranean mussel (Mytilus galloprovincialis) composition exposed to cyanotoxins as revealed by analytical pyrolysis, Application of 2,3,5-Trimethylpyrazine, the main research area is Mytilus Chrysosporum Microcystis cyanotoxin pyrolysis.

Cylindrospermopsin (CYN) and Microcystin-LR (MC-LR) are biotoxins produced by cyanobacteria species that, due to climate change and water eutrophication, proliferate together with an increase of the associated cyanotoxins. Both toxins are usually found in the aquatic environment and filter feeding organisms such as mussels are particularly exposed which may be the cause of metabolic alterations. In this work, pyrolysis gas chromatog. mass spectrometry (Py-GC/MS) is used to evaluate compositional changes in mussel (M. galloprovincialis) after exposure for 14 days to cyanotoxins of Chrysosporum ovalisporum (CYN), Microcystis aeruginosa (MC-LR) and to a combination of both toxins. The pyrolysis of mussel flesh produced complex chromatograms, with up to 100 different compounds, but very similar between treatments. Major groups found were N compounds (pyridine, N-alkyl mols.) (18.2% ± 1.5) and peptide/protein derived compounds that include alkyl indols and diketopiperazines (DKPs) (17.7% ± 2.4), series of medium chain length (C14-C22) saturated, mono and polyunsaturated fatty acids (45.1% ± 5.0), steroids (7.5% ± 0.6) and aromatics with undetermined origin (8.9% ± 1.1). A chemometric treatment of the chromatog. data allowed the discrimination between the different mussel populations exposed to cyanotoxins. The results are discussed in terms of the probable effects exerted by the biotoxins in mussel composition and the possible metabolic pathways affected.

Journal of Analytical and Applied Pyrolysis published new progress about Aphanizomenon ovalisporum. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Application of 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Meti, Puttavva published the artcileSynthesis of dipyrrolopyrazine-based sensitizers with a new π-bridge end-capped donor-acceptor framework for DSSCs: a combined experimental and theoretical investigation, Category: pyrazines, the main research area is dipyrrolopyrazine dye sensitized solar cell donor acceptor.

The strategy of developing organic dyes with exceptional optical, thermal, and stable photovoltaic properties has attracted substantial attention in the replacement of high-cost traditional dyes in DSSCs. Herein, we synthesized four dyes with a D-π-A configuration in order to study the variation produced in the optical, thermal, redox and photovoltaic properties by substitution of different donors and acceptors in the dipyrrolopyrazine (DPP) system. These push-pull systems are based on a pyrrolopyrazine spacer, end-capped with donors (N,N-dimethylamine, and thiophene) and acceptors (pyridine, -COOH, and -CN). The multidisciplinary study concerning the optical, thermal, redox, and photovoltaic characterization of the dyes reveals that compound 3a exhibits the best overall conversion efficiency as a sensitizer in TiO2 dye sensitized solar cells. The theor. calculations together with exptl. data allow us to quantify the charge transfer character of dyes.

New Journal of Chemistry published new progress about Dye-sensitized solar cells. 566205-01-4 belongs to class pyrazines, name is 2-Amino-3,5-dibromo-6-chloropyrazine, and the molecular formula is C4H2Br2ClN3, Category: pyrazines.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Lin, Liang-Jing published the artcileEffect of the bacterial community on the volatile flavour profile of a Chinese fermented condiment – Red sour soup – During fermentation, SDS of cas: 14667-55-1, the main research area is red sour soup Chinese condiment gas chromatog ion spectrometry; 16S; Gas chromatography ion mobility spectrometry (GC-IMS); Red sour soup; Secondary fermentation; Traditional Chinese condiment.

Red sour soup (RSS) is a traditional fermented seasoning used by people in Guizhou Province, China. The volatile compounds were detected by gas chromatog. ion mobility spectrometry (GC-IMS), while the bacterial community compositions were revealed by 16S sequencing. A total of 70 volatile substances were assessed, and esters, terpenes, and alcs. played a dominant role in RSS. Lactic acid bacteria (LAB) were dominant in the microbial community. During fermentation, multiple volatile flavor substances and various LAB were mainly derived from the secondary fermentation stage. The core bacteria with an important influence on volatile flavor substances were analyzed by the Mantel test, identifying Bacteroides, Lactobacillus, Lactococcus, Enterobacteriaceae, Pantoea, Clostridium, Enterobacter, unclassified genera, Caproiciproducens, Nitriliruptoraceae, Halomonas, Bradyrhizobium, Pediococcus, Caulobacteraceae, Weissella, Ligilactobacillus, and Levilactobacillus and et al.. This study provides us with useful information about flavor-generating bacteria among RSS fermentation periods. The abundances of these bacteria may be controlled to enrich the desired flavor metabolites while eliminating unwanted metabolites.

Food Research International published new progress about Acidity (total titratable). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, SDS of cas: 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Al-Dalali, Sam published the artcileCharacterization and Comparison of Aroma Profiles and Aroma-Active Compounds between Traditional and Modern Sichuan Vinegars by Molecular Sensory Science, Safety of 2,3,5-Trimethylpyrazine, the main research area is aroma compound Sichuan vinegar; GC-MS; GC-O; SAFE; Sichuan vinegar; aromas; molecular sensory science; reconstitution.

Aroma profiles and aroma-active compounds of Sichuan vinegar, which is one of the four famous vinegars in China, were systemically analyzed by solvent-assisted flavor evaporation-gas chromatog.-mass spectrometry (SAFE-GC-MS) and gas chromatog.-olfactometry (GC-O). In addition, descriptive profile anal., aroma reconstitution, and omission test were used to evaluate and compare the Sichuan modern vinegar (SMV) and Sichuan traditional vinegar (STV). A total of 99 volatile compounds were tentatively identified from the neutral and acidic fractions of both samples. Among them, 77 compounds were pos. identified after comparison with their corresponding standards Forty-two aroma-active compounds were characterized with flavor dilution (FD) factors from 1 to 6561 by aroma extract dilution assay (AEDA)-GC-O, with the highest for 2-hydroxy-3-butanone, butyrolactone, furan-2-carbaldehyde, acetic acid, and 3-oxobutan-2-yl acetate in both STV and SMV samples. Among them, 10 were identified for the first time in vinegar. Moreover, 40 aroma-active compounds were quant. determined, and 26 compounds exhibited their odor activity values (OAVs) larger than 1. The reconstituted solutions showed similar aroma profiles to the original samples in their characteristic aromas in terms of fruity, sweet, roasty, spicy, and woody notes but had slight differences in nutty and herbal notes.

Journal of Agricultural and Food Chemistry published new progress about Odor and Odorous substances. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Safety of 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Feng, Zhihui published the artcileTea aroma formation from six model manufacturing processes, Name: 2,3,5-Trimethylpyrazine, the main research area is tea aroma formation processing; Aroma character impact; Precursors; Quantitative SPME; Tea aroma; Tea processing; Tea types; Volatiles.

Tea aroma is determined by the nature of the plant, the production processes, and many other factors influencing its formation and release. The objective of this study was to investigate the impact of manufacturing processes on the aroma composition of tea. Fresh tea leaves from the same cultivar and growing area were selected for producing the six types of tea: green, white, yellow, oolong, black, and dark teas. Comprehensive anal. by gas chromatog. mass spectrometry (GC/MS) was performed for the volatiles of tea infusion, prepared by solid-phase microextraction (SPME), solid-phase extraction (SPE), and solvent assisted flavor evaporation (SAFE). A total of 168 volatile compounds were identified. Black tea has the highest volatile concentration of 710 μg/g, while green tea has the lowest concentration of 20 μg/g. Significantly affected by these processes, tea aroma mols. are formed mainly from four precursor groups: carotenoids, fatty acids, glycosides, and amino acids/sugars.

Food Chemistry published new progress about Odor and Odorous substances. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Name: 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Wang, Xiaojun published the artcileCharacterization of key aroma compounds in traditional Chinese soy sauce through the molecular sensory science technique, Recommanded Product: 2,3,5-Trimethylpyrazine, the main research area is aroma compound soy sauce mol sensory science technique.

Sensory evaluation revealed that traditional high-salt liquid-state soy sauce (THLS), a popular seasoning in China, has a caramel-like/sweet, roasted, nutty, cooked potato-like, and spicy/burnt aroma. As a comparative sample, com. high-salt liquid-state soy sauce (CHLS) showed a similar aroma profile; however, the aroma intensity was stronger and richer in THLS. Gas chromatog.-olfactometry-mass spectrometry and aroma extract dilution anal. of the aroma concentrates, prepared by solvent-assisted flavor evaporation, revealed the presence of over 70 odor-active compounds Among them, methional had the highest flavor dilution factor. Maltol, 4-ethylguaiacol, and phenylacetaldehyde were detected with a higher flavor dilution factor in THLS than in CHLS. Quant. anal. indicated that the concentrations of 11 key aroma compounds were higher in THLS than in CHLS. The sensory evaluation suggested that the aroma profile of the aroma recombination sample was similar to that of THLS. HEMF, 2-acetyl-1-pyrroline, methional, HDMF, 4-ethylguaiacol, phenylacetaldehyde, 2,3-diethylpyrazine, 2-phenylethanol, furfuryl alc., 2,3-butanediol, and maltol imparted the overall aroma profile to THLS.

LWT–Food Science and Technology published new progress about Odor and Odorous substances. 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

Huang, Jia published the artcileInvestigations on the Key Odorants Contributing to the Aroma of Children Soy Sauce by Molecular Sensory Science Approaches, Application In Synthesis of 14667-55-1, the main research area is methanethiol soy sauce odorant aroma; AEDA; FD factor; OAV; children soy sauce; gas chromatography-olfactometry; key odorants; quantitative measurements.

To investigate the key odor-active compounds in children′s soy sauce (CSS), volatile components were extracted by means of solvent extraction coupled with solvent-assisted flavor evaporation (SE-SAFE) and solid-phase microextraction (SPME). Using gas chromatog.-olfactometry (GC-O) and gas chromatog.-mass spectrometry (GC-MS), we identified a total of 55 odor-active compounds in six CSSs by comparing the odor characteristics, MS data, and retention indexes with those of authentic compounds Applying aroma extract dilution anal. (AEDA), we measured flavor dilution (FD) factors in SE-SAFE isolates, ranging from 1 to 4096, and in SPME isolates, ranging from 1 to 800. Twenty-eight odorants with higher FD factors and GC-MS responses were quantitated using the internal standard curve method. According to their quantitated results and thresholds in water, their odor activity values (OAVs) were calculated On the basis of the OAV results, 27 odorants with OAVs ≥ 1 were determined as key odorants in six CSSs. These had previously been reported as key odorants in general soy sauce (GSS), so it was concluded that the key odorants in CSS are the same as those in GSS.

Foods published new progress about Odor and Odorous substances. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Application In Synthesis of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Sonmezdag, Ahmet Salih published the artcileElucidation of hulling-induced changes in the aroma and aroma-active compounds of cv. Uzun pistachio (Pistacia vera), SDS of cas: 14667-55-1, the main research area is Pistacia aroma dry hulling method terpene pyrazine; extraction methods; key odorants; pistachio; process; volatile.

BACKGROUND : The purpose of this study was to define the effects of the hulling process on the aroma and aroma-active composition of cv. Uzun pistachio. Four different hulling processes, namely wet, wet-dry, dry-dry and brine, were applied. In addition, solvent-assisted flavor evaporation (SAFE), simultaneous distillation/extraction (SDE) and purge and trap (P&T) extraction methods were also tested to obtain the best representative aroma extract RESULTS : The results revealed that the dry-dry hulling method was the most prominent according to the aroma and aroma-active compounds, and this was especially the case with terpene compounds The method increased the content of terpenes, pyrazines and total aroma compounds By application of aroma extract dilution anal. (AEDA), a total of 18 compounds were detected, of which 11 were identified for the first time in the fruit of pistachio. 2,3-Dimethylpyrazine, trimethylpyrazine and 2-ethyl-3,5-dimethylpyrazine were the compounds that had the highest flavor dilution factors. CONCLUSION : In general, the results of the present research indicated that the hulling method highly affected the overall aroma structure of pistachios. The dry-dry hulling method is therefore suggested to manufacturers to obtain better pistachios with rich and high-quality aroma. © 2019 Society of Chem. Industry.

Journal of the Science of Food and Agriculture published new progress about Odor and Odorous substances. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, SDS of cas: 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Zhu, JianCai published the artcileCharacterization of the key aroma compounds in Laoshan green teas by application of odour activity value (OAV), gas chromatography-mass spectrometry-olfactometry (GC-MS-O) and comprehensive two-dimensional gas chromatography mass spectrometry (GC x GC-qMS), Application In Synthesis of 14667-55-1, the main research area is nonanol decanal skatole furaneol Laoshan green tea aroma olfactometry; Characteristic aroma compound; Comprehensive two-dimensional gas chromatography mass spectrometry (GC × GC-qMS); Laoshan green tea; Odor activity value (OAV); S-curve.

To investigate the key aroma compounds in Laoshan green teas (Huangshan (S1), Changling (S2), and Fangling (S3)), gas chromatog.-mass spectrometry-olfactometry (GC-MS-O), a flame photometric detector (FPD), odor activity value (OAV), and comprehensive two-dimensional gas chromatog. mass spectrometry (GC x GC-qMS) were employed. A total of 50 aroma compounds were perceived and 24 compounds were identified as important compounds related to OAV, such as di-Me sulfide (OAV: 126-146), skatole (OAV: 27-50), furaneol (OAV: 8-27), (Z)-jasmone (OAV: 16-23), 2-methylbutanal (OAV: 15-22), and 3-methylbutanal (OAV: 68-87). Furthermore, the S-curve method was used to research the effect of aroma compounds on the threshold of aroma recombination (AR). The AR thresholds decreased from 3.8 mL to 0.45, 0.66, 0.93, 0.95, 0.75, 1.09, 3.01, and 2.57 mL after addition of eight compounds (skatole, furaneol, (Z)-jasmone, α-damascenone, sclareololide, dihydroactinidiolide, vanillin, and δ-valerolactone), indicating that those compounds (OAV >1) were contributors to the overall aroma of Laoshan teas.

Food Chemistry published new progress about Flame photometric detectors. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Application In Synthesis of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem