Category: Pyrazines

Hosoya, Takamitsu published the artcileConcise Synthesis of v-Coelenterazines, HPLC of Formula: 566205-01-4, the main research area is coelenterazine vinylene analog preparation luminescence Renilla luciferase substrate; vinylene coelenterazine preparation cross coupling ring closing metathesis.

A novel synthetic method for v-coelenterazine (v-CTZ), I (R = OH), which is a vinylene-bridged analog of native CTZ with a large red-shifted luminescence property, is described. The synthesis was achieved in a concise way through the use of three sequential cross-coupling reactions and ring-closing metathesis (RCM). A newly synthesized C2-modified trifluoromethyl analog cf3-v-CTZ, I (R = CF3), showed slightly more red-shifted luminescence than v-CTZ when it was used as a substrate for Renilla luciferases.

Organic Letters published new progress about Bioluminescence. 566205-01-4 belongs to class pyrazines, name is 2-Amino-3,5-dibromo-6-chloropyrazine, and the molecular formula is C4H2Br2ClN3, HPLC of Formula: 566205-01-4.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Jia, Xiao published the artcileKey Odorant Differences in Fragrant Brassica napus and Brassica juncea Oils Revealed by Gas Chromatography-Olfactometry, Odor Activity Values, and Aroma Recombination, Related Products of pyrazines, the main research area is Brassica oil fragrant aroma recombination olfactometry; Brassica juncea oil; Brassica napus oil; aroma extract dilution analysis; aroma reconstitution; solvent-assisted flavor evaporation combined with ultrasound.

Fragrant Brassica species seed oils (FBO) produced in China are mainly obtained from rapeseed (Brassica napus: B. napus) and mustard seeds (Brassica juncea: B. juncea). The characterization and differences of aroma profiles between those two species remain unclear. In this study, the volatile compounds in FBOs were systemically extracted by headspace solid-phase microextraction and solvent-assisted flavor evaporation combined with ultrasound and identified by comprehensive two-dimensional gas chromatog. and time-of-flight mass spectrometry (GCxGC-TOFMS) and gas chromatog.-olfactometry (GC-O). Ninety-three odorants were identified as aroma-active compounds with flavor dilution (FD) factors ranging from 1 to 6561. Moreover, 63 key compounds exhibited their odor activity values (OAVs) to be greater than 1. The oils of the two species were successfully recombinated with their key odorants. B. juncea oils presented stronger pungent-like, pickled-like, and fishy like notes compared to B. napus oils. The key odor differences were primarily attributed to the concentration of 3-butenenitrile, 4-(methylsulfanyl)butanenitrile, 5-(methylsulfanyl)pentanenitrile, 3-isothiocyanato-1-propene, 3-methyl-3-butenenitrile, isothiocyanatocyclopropane, (methylsulfanyl)acetonitrile, di-Me sulfide, di-Me trisulfide, and 3-(methyldisulfanyl)-1-propene. This work provides a guide for the selection of raw materials and odor markers in fragrant B. napus and B. juncea oils.

Journal of Agricultural and Food Chemistry published new progress about Brassica juncea. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Related Products of pyrazines.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

El Majdoub, Yassine Oulad published the artcileChemical characterization of three accessions of Brassica juncea L. extracts from different plant tissues, Synthetic Route of 14667-55-1, the main research area is chem composition root stem leaf Brassica; Brassica juncea spp.; GC; HPLC; foods; metabolites; non-volatile; nutraceuticals; volatile.

Indian mustard or Brassica juncea (B. juncea) is an oilseed plant used in many types of food (as mustard or IV range salad). It also has non-food uses (e.g., as green manure), and is a good model for phytoremediation of metals and pesticides. In recent years, it gained special attention due to its biol. compounds and potential beneficial effects on human health. In this study, different tissues, namely leaves, stems, roots, and flowers of three accessions of B. juncea: ISCI 99 (Sample A), ISCI Top (Sample B), and “”Broad-leaf”” (Sample C) were analyzed by HPLC-PDA/ESI-MS/MS. Most polyphenols identified were bound to sugars and phenolic acids. Among the three cultivars, Sample A flowers turned were the richest ones, and the most abundant bioactive identified was represented by Isorhamnetin 3,7-diglucoside (683.62 μg/100 mg dry weight (DW) in Sample A, 433.65 μg/100 mg DW in Sample B, and 644.43 μg/100 mg DW in Sample C). In addition, the most complex samples, viz. leaves were analyzed by GC-FID/MS. The major volatile constituents of B. juncea L. leaves extract in the three cultivars were benzenepropanenitrile (34.94% in Sample B, 8.16% in Sample A, 6.24% in Sample C), followed by benzofuranone (8.54% in Sample A, 6.32% in Sample C, 3.64% in Sample B), and phytone (3.77% in Sample B, 2.85% in Sample A, 1.01% in Sample C). The overall evaluation of different tissues from three B. juncea accessions, through chem. anal. of the volatile and non-volatile compounds, can be advantageously taken into consideration for future use as dietary supplements and nutraceuticals in food matrixes.

Molecules published new progress about Brassica juncea. 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

Grossmann, Kora Kassandra published the artcileNew insights into the flavoring potential of cricket (Acheta domesticus) and mealworm (Tenebrio molitor) protein hydrolysates and their Maillard products, Computed Properties of 14667-55-1, the main research area is Acheta Tenebrio protein hydrolyzate Maillard product flavoring potential; Cricket and Mealworm Protein; Enzymatic Hydrolysis; Flavor Analysis; Maillard Reaction; Sensory Evaluation.

Insect proteins have an earthy-like flavor and have not shown great flavor potential for food applications so far. In this study, insect proteins of cricket Acheta domesticus and mealworm Tenebrio molitor larvae were first enzymically hydrolyzed using two peptidase preparations (Flavourzyme1000L and ProteaseA “”Amano””2SD). Xylose was then added to facilitate Maillard reactions (30 min, T = 98°C, 1% (w/v) xylose). A comprehensive sensory evaluation showed that both the hydrolysis and the Maillard reactions changed the flavor description of the samples significantly to more complex and savory-like taste profiles (27 descriptors for cricket and 39 descriptors for mealworm protein). In addition, 38 odor-active mols. were identified using gas chromatog.-olfactometry (1 alc., 5 acids, 11 aldehydes, 5 ketones and 16 heterocyclic compounds). The results showed impressively that the flavoring potential of insect proteins was significantly enhanced with resp. processing.

Food Chemistry published new progress about Acheta domesticus. 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

Pena-Correa, Ruth Fabiola published the artcileFluidized bed roasting of cocoa nibs speeds up processing and favors the formation of pyrazines, Application of 2,3,5-Trimethylpyrazine, the main research area is cocoa bean fluidized bed roasting volatile compound formation.

Roasting is an important step in cocoa processing causing water loss and generating volatile compounds responsible for chocolate aroma like nitrogen-heterocycles. In this study, the comparison of two techniques, oven roasting, and fluidized bed roasting, in terms of effective water diffusivity (De) and activation energies of formation (Ea) of nitrogen-heterocycles was achieved with cocoa nibs. Fluidized bed roasting, recognized for its energy efficiency and low-footprint synthesis, was 16 times faster than oven roasting. The order of magnitude of De in fluidized-bed-roasted nibs was -8, while it was -9 in the oven-roasted nibs. Moreover, the aw was 50% higher in fluidized-bed-roasted nibs than in the oven-roasted ones. The Ea of nitrogen-heterocycles ranged roughly between 40 and 80 kJ/mol. Those values were lower under fluidized bed roasting than under oven roasting. The more effortless water mobility within fluidized-bed-roasted cocoa demanded lower Ea, and favored the formation of nitrogen-heterocyclics. This study can inspire cocoa manufacturers and equipment designers to pursue the formation of nitrogen-heterocycles during the roasting process of cocoa. It can be done either by adapting and scaling the current fluidized bed coffee roasters to cocoa beans or nibs; or by exploring other alternatives capable of leading enough water diffusivity and water activity in the cocoa nibs, as reported here. These physicochem. conditions undoubtedly boosted the formation of volatile compounds responsible for chocolate aroma, e.g., the pyrazines, without carrying the formation of typical-burn volatile compounds This natural way of favoring the generation of pyrazines in cocoa nibs could contribute to clean labels by reducing or avoiding the subsequent use of flavorings. The implementation of efficient heat-transfer techniques during roasting, e.g., fluidized bed roasting, could reduce the processing cost and improve sustainability. Studies in the matter of sensory profile, and energy consumption/conversion are called for future research.

Innovative Food Science & Emerging Technologies published new progress about Activation energy. 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

Hao, Yining published the artcileEffect of static-state fermentation on volatile composition in rapeseed meal, Computed Properties of 14667-55-1, the main research area is rapeseed meal volatile composition static state fermentation; Tetramethylpyrazine; fermentation; rapeseed meal; volatile components.

BACKGROUND : Fermented rapeseed meal has been used as an alternative protein source for animal feed, but the volatile compounds and how their contents change during fermentation have not been reported. To clarify the effect of static-state fermentation on its aroma, the volatile compounds of rapeseed meal during different stages of fermentation were analyzed using an electronic nose system and headspace solid-phase microextraction-gas chromatog.-mass spectrometry. RESULTS : The results suggested that the volatile compounds in the raw rapeseed meal, mostly hydrocarbons and some aldehydes, were lost. The levels of the volatile compounds resulting from microbial metabolism, especially pyrazines, greatly increased during fermentation Nonanal was the dominant volatile measured in the headspace of raw rapeseed meal. However, the volatile compounds found at high concentrations in rapeseed meal after 5 days of fermentation were tetramethylpyrazine, followed by butanoic acid, benzenepropanenitrile, 2-methylbutanoic acid, trimethylamine, 2,3,5-trimethyl-6-ethylpyrazine, and 2,3,5-trimethylpyrazine. CONCLUSION : The fermentation process could significantly change the composition and content of volatile compounds in rapeseed meal. The results may provide reference data for studies on the choice of fermentation period and formation mechanism of flavor substances in fermented rapeseed meal.

Journal of the Science of Food and Agriculture published new progress about Bacillus subtilis. 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

Yu, Jinhui published the artcileEffects of different probiotic combinations on the components and bioactivity of Spirulina, Synthetic Route of 14667-55-1, the main research area is Bacillus Spirulina probiotic combination bioactivity; Bacillus strains; Spirulina; antioxidant and antimicrobial activity; lactic acid bacteria; mixed fermentation.

Spirulina acts as a good dietary nutritional supplement. However, few research studies have been conducted on its fermentation Three groups of probiotic combinations, lactic acid bacteria, Bacillus strains, and their mixture, were used to investigate Spirulina fermentation The results showed that lactic acid bacteria significantly increased the content of amino acids and the ratio of essential amino acids to total amino acids in the fermented Spirulina, compared with the unfermented Spirulina, and this trend was enhanced by the strains’ mixture However, compared to unfermented Spirulina, the amino acid levels were significantly decreased after fermentation with Bacillus strains and so was the total free amino acid and essential amino acid content. Fermentation significantly reduced the contents of the offensive components of Spirulina, with significant differences among the three mixed bacterial treatments. Moreover, Bacillus strain fermentation increased the contents of flavonoids and polyphenols compared to the unfermented Spirulina, and significantly enhanced 1,1-diphenyl-2-trinitrophenylhydrazine free-radical scavenging ability and total antioxidant ability. On the contrary, treatments with lactic acid bacteria and the mixture of lactic acid bacteria and Bacillus strains endowed the fermented supernatants with good antibacterial ability. The results showed that probiotic fermentation has a good effect on Spirulina and can serve as a new procedure for developing new Spirulina-containing food items.

Journal of Basic Microbiology published new progress about Bacillus subtilis. 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

Yu, Yuanrui published the artcileEffects of different cooking methods on free fatty acid profile, water-soluble compounds and flavor compounds in Chinese Piao chicken meat, Formula: C7H10N2, the main research area is oleic acid phenylacetaldehyde frying roasting boiling Piao chicken meat; Free fatty acids; Piao chicken; Small molecular metabolites; Volatile compounds.

Piao chicken breast meat was cooked by three different methods (boiling, frying and roasting). Non-volatile and volatile substances in the three cooked chicken were analyzed by GC-MS, UPLC-Q-Exactive-MS and GC-IMS, resp. Arachidonic acid was the highest in boiled chicken, oleic acid was the highest in roasted chicken, linoleic acid, EPA and DHA were the highest in fried chicken. Compared with the control group, the total content of small mol. metabolites of chicken in each treatment group decreased. The total amount of amino acids in roasted chicken was 2.90 times of that in boiled chicken (P < 0.05), and 2.23 times of that in fried chicken (P < 0.05). A total of 26 volatile flavor compounds were detected. Phenylacetaldehyde etc. were the main volatile flavor compounds in boiled chicken, 3-butanedione etc. were the main volatile flavor compounds in fried chicken, while 3-methylbutyraldehyde etc. were the main volatile flavor compounds in roasted chicken. Food Research International published new progress about Boiling (cooking). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Formula: C7H10N2.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Okabe, Yui published the artcileOdor-active compounds contributing to the characteristic aroma of shrimp cooked whole, including shells and viscera, Application of 2,3,5-Trimethylpyrazine, the main research area is Pleoticus cooking characteristic aroma odor.

Shrimps and prawns are known to generate a characteristic and pleasant aroma when cooked whole, including their shells and viscera. This study investigated this characteristic aroma of whole-roasted shrimp using Argentine red shrimp (Pleoticus muelleri). Shrimps were roasted in an oven, and the aroma changed upon the usage of whole shrimp. The aroma attributes of “”roasted”” and “”rich”” were significantly improved. We performed an anal. of volatile compounds to identify the contributors to roasted and rich aromas and identified 17 odor-active compounds Heterocyclic compounds including pyrazines, thiazolines, and thiazoles were major contributors to the aroma of whole roasted shrimp. In aroma extract dilution anal., 2,6-dimethylpyrazine, trimethylpyrazine, 2-ethyl-3,5-dimethylpyrazine, 2-acetyl-2-thiazoline, methional, 2-acetylthiazole, 2,5-dimethylpyrazine, 2,3-dimethylpyrazine, and indole were detected with higher flavor dilution factors than were other odor-active compounds Furthermore, sensory evaluation anal. confirmed that pyrazines contributed to the roasted aroma, and thiazolines and thiazoles contributed to both the roasted and rich aromas. In conclusion, pyrazines, thiazolines, and thiazoles derived from shrimp shells or viscera were the major contributors to the characteristic aroma of whole roasted shrimp and strongly influenced the aroma impression of shrimp dishes.

European Food Research and Technology published new progress about Boiling (cooking). 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

Li, Mengru published the artcileFormation of Volatile Heterocyclic Compounds and Open-Chain Amides of Theanine in Model Systems with Glucose, Tea Leaves, and Tea Extract under Tea-Roasting Conditions, Application of 2,3,5-Trimethylpyrazine, the main research area is volatile heterocyclic open chain amide theanine glucose tea roasting; 1-ethyl-1,5-dihydro-2H-pyrrol-2-one; Maillard reactions; N-ethylsuccinimide; pyrazines; tea roasting; theanine.

Theanine is a non-proteinogenic amino acid found in the tea plant Camellia sinensis. At an elevated temperature (>90 °C), it released two major volatile compounds 1-ethyl-1,5-dihydro-2H-pyrrol-2-one and N-ethylsuccinimide. Other products were identified, including 10 pyrroles and 12 amides/imides. The formation of the two major compounds was proposed to be initiated by the deamination of theanine and through the intermediate α-keto acid. In the presence of glucose, the two major products and many other volatiles from theanine thermal degradation were accelerated and further Maillard reactions occurred. A total of 56 compounds were identified in the model system of theanine and glucose, including 12 amides/imides, 16 pyrazines, 16 pyrroles and other N-heterocycles, and 12 furans and other O-heterocycles. Although most of the reaction products were detected in tea leaves and in their aqueous extract with or without the addition of theanine under the same experiment conditions, imides and amides were considerably suppressed, left only minute amounts, or were even no longer detectable. Pyrazines and pyrroles were also shown at reduced concentrations as a result of the interaction with tea components but to a lesser extent. A total of 16 and 12 pyrazines were identified in the theanine/glucose reaction system and tea leaves/aqueous extract after roasting, resp. The results indicated that pyrazines and other main volatiles in roasted tea leaves were formed from the Maillard reactions of the aqueous fraction of tea leaves. Theanine participated in the formation of pyrazines in tea leaves under roasting conditions.

Journal of Agricultural and Food Chemistry published new progress about Camellia sinensis. 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