Category: 5405-41-4

Ochiai, Nobuo published the artcileFractionated stir bar sorptive extraction using conventional and solvent-assisted approaches for enhanced identification capabilities of aroma compounds in beverages, HPLC of Formula: 5405-41-4, the main research area is stir bar sorptive extraction aroma beverages green tea beer; Aroma compounds; Fractionated stir bar sorptive extraction (Fr-SBSE); Roasted green tea; Solvent-assisted stir bar sorptive extraction (SA-SBSE); Stout beer.

For successful profiling of aroma carriers in food samples, a highly efficient extraction method is mandatory. A two-step stir bar sorptive extraction (SBSE) approach, namely fractionated SBSE (Fr-SBSE), was developed to improve both the organoleptic and the chem. identification of aroma compounds in beverages. The first extraction consists of a conventional mSBSE using three polydimethylsiloxane (PDMS) stir bars (1stmSBSE). This is followed by a solvent-assisted mSBSE performed on the same sample using three solvent-swollen PDMS stir bars (2nd SA-mSBSE). The 1stmSBSE mainly extracts apolar/medium polar solutes with log Kow values >2, while the 2nd SA-mSBSE mainly extracts polar solutes with log Kow values <2. After this two-step fractionation procedure, either thermal desorption (TD) or liquid desorption - large volume injection (LD-LVI), followed by GC-MS is performed on each set of three stir bars. A real-life sample of roasted green tea was used for method development. The performance of the Fr-SBSE method is further illustrated with sensory evaluations and GC-MS anal. for a stout beer sample. Compared to an extraction procedure with SA-mSBSE only, Fr-SBSE including a 1stmSBSE and a 2nd SA-mSBSE reduced co-elution of aroma compounds in the chromatograms and was capable of providing improved mass spectral quality for identification of 17 addnl. compounds in roasted green tea, and 12 addnl. compounds in stout beer, resp. Moreover, odor description and characterization were clearly improved. Journal of Chromatography A published new progress about Beverages. 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, HPLC of Formula: 5405-41-4.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Velazquez, Rocio published the artcileUsing Torulaspora delbrueckii killer yeasts in the elaboration of base wine and traditional sparkling wine, HPLC of Formula: 5405-41-4, the main research area is Torulaspora Saccharomyces polysaccharide protein aroma fermentation sparkling wine; 3‑Ethoxy‑1‑propanol (PubChem CID: 8109); 4‑Vinylguaiacol (PubChem CID: 332); Aroma; Butanoic acid (PubChem CID: 264); Ethyl hexanoate (PubChem CID: 31265); Ethyl octanoate (PubChem CID: 7799); Ethyl propanoate (PubChem CID: 7749); Foam; Isobutyric acid (PubChem CID: 6590); Mannan; Polysaccharide; Second fermentation; Yeast death.

For still wines, killer strains of Torulaspora delbrueckii can be used instead of non-killer strains to improve this species’ domination during must fermentation, with an ensured, reliable impact on the final wine quality. The present work analyzed the usefulness of these killer yeasts for sparkling-wine making. After the first fermentation, the foaming capacity of T. delbrueckii base wines was very low compared to Saccharomyces cerevisiae base wines. Significant pos. correlations of foaming parameters were found with the amounts of C4-C16 Et esters and proteins, and neg. with some anti-foaming alcs. produced by each yeast species. There were, however, no evident pos. effects of polysaccharides on those parameters. The organoleptic quality of the T. delbrueckii base wines was judged inappropriate for sparkling-wine making, so that the following second-fermentation experiments only used a single assemblage of S. cerevisiae base-wines. While second fermentation was completed with inoculation of S. cerevisiae (both alone and mixed with T. delbrueckii) to yield dry sparkling wines with high CO2 pressure, single inoculation with T. delbrueckii did not complete this fermentation, leaving sweet wines with poor CO2 pressure. Yeast death due to CO2 pressure was much greater in T. delbrueckii than in S. cerevisiae, making any killer effect of S. cerevisiae over T. delbrueckii irrelevant because no autolyzed cells were found during the first days of mixed-inoculated second fermentation Nonetheless, the organoleptic quality of the mixed-inoculated sparkling wines was better than that of wines single-inoculated with S. cerevisiae, and showed no deterioration in foam quality. This seemed mainly to be because T. delbrueckii increased the amounts of Et propanoate and some acids (e.g., isobutyric and butanoic), alcs. (e.g., 3-ethoxy-1-propanol), and phenols (e.g., 4-vinylguaiacol). For these sparkling wines, no significant correlations between foaming parameters and aroma compounds were found, probably because the differences in foaming parameter values among these wines were fairly small. This is unlike the case for the base wines for which there were large differences in these parameters, which facilitated the anal. of the influence of aroma compounds on base-wine foamability.

International Journal of Food Microbiology published new progress about Food foams. 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, HPLC of Formula: 5405-41-4.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Takemoto, Kohei published the artcileSite-selective esterifications of polyol β-hydroxyamides and applications to serine-selective glycopeptide modifications, Related Products of esters-buliding-blocks, the main research area is glycopeptide synthesis serine sugar steric hindrance; hydroxyamide polyol esterification hydroxyl group acylation.

The site-selective acylations of β-hydroxyamides in the presence of other hydroxyl groups are described. Central to the success of this modification is the metal-template-driven acylation using pyridine ketoxime esters as acylating reagents in combination with CuOTf. This strategy enables β-hydroxyl groups to be site-selectively acylated in various derivatives, including sterically hindered secondary β-alc. The utility of this methodol. is showcased by the serine-selective modification of a glycopeptide with unprotected sugar.

Organic Letters published new progress about Acylation. 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, Related Products of esters-buliding-blocks.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Hao, Guojun published the artcileCatalytic depolymerization of the dealkaline lignin over Co-Mo-S catalysts in supercritical ethanol, Application In Synthesis of 5405-41-4, the main research area is dealkaline lignin catalytic depolymerization property.

In this work, lignin depolymerization was examined over CoMo sulfide catalysts supported on different carriers in supercritical ethanol system. The temperature, time, MoS2 and carrier effects on the lignin depolymerization were investigated. 95.76% liquefaction yield with negligible char was achieved over Co-Mo-S/ZrO2 at 340° for 150 min. The liquid product was mainly composed of C4-C8 alcs., C4-C10 esters and C7-C10 aromatic compounds The synergistic effect of active sites and acid-base sites on support played an important role in lignin depolymerization Furthermore, the Co-Mo-S/ZrO2 catalyst is reusable with 8% loss in liquefaction yield after 5 cyclic runs. We believe that acid/base carriers or additives that can promote the medium to generate abundant free radicals or ions to replace external hydrogen pressure are one of the prospects for the design of depolymerization lignin catalysts.

Biomass and Bioenergy published new progress about Adsorption. 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, Application In Synthesis of 5405-41-4.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Oishi, Masataka published the artcileRing-Opening Polymerization of ε-Caprolactone Initiated by Multinuclear Aluminum Methanetris(aryloxido) Complexes, HPLC of Formula: 5405-41-4, the main research area is aluminum methanetrisaryloxido ring opening polymerization initiator equilibrium stabilization; crystal structure mol aluminum methanetrisaryloxido complex preparation optimized conformation.

Dinuclear aluminum complexes (2a-/2b-THF) supported by a methanetris(aryloxide) were synthesized by dealumination of the corresponding trinuclear aluminum complexes (1a and 1b) in THF solvent. Treatment of methylaluminum derivatives 1a and 2a-THF with one equivalent of benzyl alc. led to the formation of monobenzyloxides 3a and 4a with no nuclearity change, resp. Ring-opening polymerization (ROP) of ε-caprolactone by these multinuclear aluminum complexes were studied, and good polymerization activity and mol. weight control were observed when 4a was employed as the initiator. During the ROP, the three aryloxide moieties of the supporting ligand were observed to be equivalent by 1H NMR spectroscopy, reflecting the rapid equilibrium of coordination between Al2 centers and a Lewis base. Ester-tethered alkoxides 6-9 were synthesized and structurally characterized. On the basis of the ester adduct structures, both syn- and anti-CL adducts of methoxide 10 were probed using DFT calculation Kinetic study for the 4a-initiated ROP was performed and revealed that the rate-determining step is switched by polymerization conditions. These results suggest that the two aluminum centers in the active Al2 species cooperatively work as a coordination site toward Lewis bases such as CL and as a stabilization site for the insertion of an alkoxide terminus.

Organometallics published new progress about Alcoholysis. 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, HPLC of Formula: 5405-41-4.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Valera, Maria Jose published the artcileWine Aroma Characterization of the Two Main Fermentation Yeast Species of the Apiculate Genus Hanseniaspora, Quality Control of 5405-41-4, the main research area is Hanseniaspora apiculate genus wine aroma fermentation yeast species.

Hanseniaspora species are the main yeasts isolated from grapes and grape musts. Regarding genetic and phenotypical characterization, especially fermentative behavior, they can be classified in two technol. clusters: the fruit group and the fermentation group. Among the species belonging to the last group, Hanseniaspora osmophila and Hanseniaspora vineae have been previously isolated in spontaneous fermentations of grape must. In this work, the oenol. aptitudes of the two species of the fermentation group were compared with Saccharomyces cerevisiae and the main species of the fruit group, Hanseniaspora uvarum. Both H. osmophila and H. vineae conferred a pos. aroma to final wines and no sensory defects were detected. Wines fermented with H. vineae presented significantly higher concentrations of 2-phenylethyl, tryptophol and tyrosol acetates, acetoin, mevalonolactone, and benzyl alc. compared to H. osmophila. Sensorial anal. showed increased intensity of fruity and flowery notes in wines vinificated with H. vineae. In an evolutionary context, the detoxification of alcs. through a highly acetylation capacity might explain an adaptation to fermentative environments. It was concluded that, although H. vineae show close alc. fermentation adaptations to H. osmophila, the increased activation of phenylpropanoid metabolic pathway is a particular characteristic of H. vineae within this important apiculate genus.

Fermentation published new progress about Acetylation. 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, Quality Control of 5405-41-4.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Zaccone, Ferdinando published the artcileAn Alternative Enzymatic Route to the Ergogenic Ketone Body Ester (R)-3-Hydroxybutyl (R)-3-Hydroxybutyrate, Related Products of esters-buliding-blocks, the main research area is esterhydroxybutylhydroxybutyrate ergogenic ketone body alternative enzymic route.

Recent studies have highlighted the therapeutic and ergogenic potential of the ketone body ester, (R)-3-hydroxybutyl-(R)-3-hydroxybutyrate. In the present work, the enzymic synthesis of this biol. active compound is reported. The (R)-3-hydroxybutyl-(R)-3-hydroxybutyrate has been produced through the transesterification of racemic Et 3-hydroxybutyrate with (R)-1,3-butanediol by exploiting the selectivity of Candida antarctica lipase B (CAL-B). The needed (R)-1,3-butanediol was in turn obtained from the kinetic resolution of the racemate achieved by acetylation with vinyl acetate, also in this case, thanks to the enantioselectivity of the CAL-B used as catalyst. Finally, the stereochem. inversion of the unreacted (S) enantiomers of the Et 3-hydroxybutyate and 1,3- butanediol accomplished by known procedure allowed to increase the overall yield of the synthetic pathway by incorporating up to 70% of the starting racemic reagents into the final product.

Catalysts published new progress about Acetylation. 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, Related Products of esters-buliding-blocks.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Soelter, Jan published the artcileComputational exploration of molecular receptive fields in the olfactory bulb reveals a glomerulus-centric chemical map, SDS of cas: 5405-41-4, the main research area is dorsal olfactory bulb glomerulus centric chem map computational exploration.

Progress in olfactory research is currently hampered by incomplete knowledge about chem. receptive ranges of primary receptors. Moreover, the chem. logic underlying the arrangement of computational units in the olfactory bulb has still not been resolved. We undertook a large-scale approach at characterizing mol. receptive ranges (MRRs) of glomeruli in the dorsal olfactory bulb (dOB) innervated by the MOR18-2 olfactory receptor, also known as Olfr78, with human ortholog OR51E2. Guided by an iterative approach that combined biol. screening and machine learning, we selected 214 odorants to characterize the response of MOR18-2 and its neighboring glomeruli. We found that a combination of conventional physico-chem. and vibrational mol. descriptors performed best in predicting glomerular responses using nonlinear Support-Vector Regression. We also discovered several previously unknown odorants activating MOR18-2 glomeruli, and obtained detailed MRRs of MOR18-2 glomeruli and their neighbors. Our results confirm earlier findings that demonstrated tunotopy, i.e., glomeruli with similar tuning curves tend to be located in spatial proximity in the dOB. In addition, our results indicate chemotopy, i.e., a preference for glomeruli with similar physico-chem. MRR descriptions being located in spatial proximity. Together, these findings suggest the existence of a partial chem. map underlying glomerular arrangement in the dOB. Our methodol. that combines machine learning and physiol. measurements lights the way towards future high-throughput studies to deorphanise and characterize structure-activity relationships in olfaction.

Scientific Reports published new progress about Homo sapiens. 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, SDS of cas: 5405-41-4.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Korenika, Ana-Marija Jagatic published the artcileInfluence of L. thermotolerans and S. cerevisiae commercial yeast sequential inoculation on aroma composition of red wines (Cv Trnjak, Babic, Blatina and Frankovka), COA of Formula: C6H12O3, the main research area is cerevisiae yeast aroma red wines.

Even though Saccharomyces cerevisiae starter cultures are still largely used nowadays, the non-Saccharomyces contribution is re-evaluated, showing pos. enol. characteristics. Among them, Lachancea thermotolerans is one of the key yeast species that are desired for their contribution to wine sensory characteristics. The main goal of this work was to explore the impact of L. thermotolerans com. yeast strain used in sequential inoculation with S. cerevisiae com. yeast on the main enol. parameters and volatile aroma profile of Trnjak, BabiC, Blatina, and Frankovka red wines and compare it with wines produced by the use of S. cerevisiae com. yeast strain. In all sequential fermented wines, lactic acid concentrations were significantly higher, ranging from 0.20 mg/L in Trnjak up to 0.92 mg/L in Frankovka wines, while reducing alc. levels from 0.1% volume/volume in Trnjak up to 0.9% volume/volume in Frankovka wines. Among volatile compounds, a significant increase of Et lactate and iso-Bu acetate, geraniol, and geranyl acetate was detected in all wines made by use of L. thermotolerans. In BabiC wines, the strongest influence of sequential fermentation was connected with higher total terpenes and total ester concentrations, while Trnjak sequentially fermented wines stood up with higher total aldehyde, volatile phenol, and total lactone concentrations Control wines, regardless of variety, stood up with higher concentrations of total higher alcs., especially isoamyl alc. The present work contributed to a better understanding of the fermentation possibilities of selected non-Saccharomyces strains in the overall red wine quality modeling.

Fermentation published new progress about Fermentation. 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, COA of Formula: C6H12O3.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Izquierdo-Canas, P. M. published the artcileEffect of fermentation temperature on volatile compounds of Petit Verdot red wines from the Spanish region of La Mancha (central-southeastern Spain), Formula: C6H12O3, the main research area is volatile compound Petit Verdot red wine fermentation.

The aim of this work was to research the relationship between volatile composition of Petit Verdot red wines and the fermentation temperature Winemaking process was carried out at 17°C, 21°C, and 25°C temperatures Solid-phase extraction (SPE) and gas chromatog.-mass spectrometry (GC-MS) were used to analyze volatile compounds The odor activity values (OAVs) from the different compounds were classified into seven odorant series that describe the aroma profile (fruity, floral, green/fresh, sweet, spicy, fatty, and other odours). The value of each aromatic series was obtained by adding the OAVs of the volatile compounds to each series. The volatile composition was significantly affected by the temperature of the fermentation In general, the increase in the fermentation temperature of La Mancha Petit Verdot red wines from 17 to 25°C produced an increase in the concentration of volatile aroma compounds The highest aroma contributions to Petit Verdot wine were fruity, sweet and floral series, followed by fatty and spicy series, regardless of fermentation temperature The highest values of aromatic series were found in wines fermented at 21°C. The results of this work show that changes in the fermentation temperature of wines can have a significant impact on their volatile compound profile.

European Food Research and Technology published new progress about Fermentation. 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, Formula: C6H12O3.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics