Category: esters-buliding-blocks

Yun, Wan-Chu published the artcileMicrowave Irradiation-Enhanced Catalytic Transfer Hydrogenation of Levulinic Acid to γ-Valerolactone Using Ruthenium: A Comparative Study with Conventional Heating Processes, Computed Properties of 539-88-8, the main research area is levulinic acid ruthenium catalyst hydrogenation microwave Irradiation.

Conversion of biomass-derived levulinic acid to γ-valerolactone (GVL) via catalytic transfer hydrogenation (CTH) using conventional oven heating (COH) is associated with issues, such as long reaction time, and low yield. Microwave irradiation (MWI) appears to be a solution to address these issues as MWI can shorten reaction times and enhance yields. To explore effectiveness of MWI for LA conversion, MWI and COH are compared for LA conversion via CTH catalyzed by a model catalyst, Ru/C. Through investigating the effects of temperature and reaction time, MWI is validated to shorten the reaction time and enhance LA conversion efficiencies in comparison with COH. The optimal condition for the full LA conversion to GVL by Ru/C using MWI is 160°C for 30 min with 10 mg (Ru/C)/mL (2-PrOH). MWI is also validated to improve conversion of several common levulinate esters (LAEs) to GVL. The regenerated Ru/C can also exhibit almost the same catalytic activity as the pristine Ru/C for LA conversion using MWI. These results indicate that Ru/C is a highly-effective catalyst for LA conversion and MWI can further enhance LA conversion by Ru/C by shortening reaction time and increasing yield of GVL. Thus, MWI is a promising process for enhancing biomass conversion.

Waste and Biomass Valorization published new progress about Biomass. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Computed Properties of 539-88-8.

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

Yang, Shuhua published the artcileStudy on the influence of different catalysts on the preparation of ethyl levulinate from biomass liquefaction, Safety of Ethyl 4-oxopentanoate, the main research area is ethyl levulinate biomass liquefaction heating.

The liquefaction experiments of straw biomass under heating and pressure were carried out with sulfuric acid and three ionic liquids as catalysts, 1-Butyl-3-methylimidazolium chloride ([BMIM] [Cl]), 1-Butyl-3-methylimidazolium hydrogen sulfate ([BMIM] [HSO4]), 1-methyl-3-(4-sulfobutyl) imidazole bisulfate ([HSO3-BMIM] [HSO4]), and anhydrous ethanol as solvent. The effects of catalyst type and dosage, reaction time and reaction temperature on liquefaction were investigated and optimized. The results showed that under the catalysis of sulfuric acid, the yield of Et levulinate was the highest; [HSO3-BMIM] [HSO4], the conversion of raw materials was the highest; when sulfuric acid was used as catalyst, the optimum reaction conditions were catalyst dosage 10%, reaction temperature 190 °C, reaction time 60 min, the yield of Et levulinate (EL) was 18.11%, and the conversion of raw materials was 75%. When [HSO3-BMIM] [HSO4] was used as catalyst, the optimum reaction conditions were as follows: catalyst dosage 26%, reaction temperature 200 °C, reaction time 60 min, the yield of EL was 10.2%, conversion of raw material 85.31%.

Journal of Biobased Materials and Bioenergy published new progress about Biomass. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Safety of Ethyl 4-oxopentanoate.

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

Bunrit, Anon published the artcilePhoto-Thermo-Dual Catalysis of Levulinic Acid and Levulinate Ester to γ-Valerolactone, SDS of cas: 539-88-8, the main research area is photo thermo dual catalysis levulinic acid levulinate ester valerolactone.

Herein, we developed photo-thermo-dual catalytic strategies for the production of γ-valerolactone (GVL) from levulinic acid (LA) and its ester using platinum-loaded TiO2 as a dual-functional catalyst. Both catalytic systems were evaluated under mild reaction conditions. In the photocatalysis system, a base plays crucial roles in the conversion of LA and EL to GVL. The control experiments reveal that plausible mechanistic pathways of both systems proceed via the hydrogenation of the ketone group of LA to the corresponding alc. as a major intermediate followed by a subsequent cyclization step to GVL. This dual-functional catalyst provides alternative strategies for the conversion of LA and its ester into GVL, which could pave the way for biomass utilization in a more effective and practical manner.

ACS Catalysis published new progress about Biomass. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, SDS of cas: 539-88-8.

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

Wu, Jiaming published the artcileDesign of graphene oxide by a one-pot synthetic route for catalytic conversion of furfural alcohol to ethyl levulinate, Synthetic Route of 539-88-8, the main research area is ethyl levulinate furfural alc graphene oxide catalytic conversion.

Graphene oxide (GO) has abundant oxygen-containing functionalities such as hydroxyl groups and carboxyl groups with distinct acidities. This feature makes GO a potential solid acid catalyst for the acid-catalyzed reactions such as the production of Et levulinate (EL), a platform chem., from the acid-treatment of furfuryl alc. (FA). The structure and functionalities of GO are closely related to its catalytic performance, and thus it is necessary to establish the relationship between the chem. structure and the catalytic properties of GO. To achieve this aim, in this work, the GO catalysts were designed by a facile one-pot synthetic route with no subsequent modification. By controlling the parameters of oxidation process in preparation, multiple functional groups were immobilized onto graphitic substrate, significantly impacting the catalytic activity of GO in the conversion of FA to EL in an ethanol (EtOH) medium. The results showed that, the oxidation process significantly influenced the distribution of oxygen-containing functionalities on the surface of GO. The amount of the oxygen-containing functionalities can be adjusted by the oxidation parameters such as oxidizing agent equivalent, reaction time and temperature, while the organosulfate can only be remained at a moderate oxidation temperature The existence of the synergistic effect between the oxygen-containing functionalities and the organosulfate functionalities promoted the catalytic activity of GO for the acid-catalyzed conversion of FA to EL. This work provides a new strategy of design and development of functional graphene-based catalysts for the acid-catalyzed reactions, and lays foundation of the practicability of GO in biomass conversion.

Journal of Chemical Technology and Biotechnology published new progress about Biomass. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Synthetic Route of 539-88-8.

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

Abe, Takayuki published the artcileCharacterization of a new Saccharomyces cerevisiae isolated from hibiscus flower and its mutant with L-leucine accumulation for awamori brewing, Name: Ethyl octanoate, the main research area is Saccharomyces hibiscus flower leucine awamori brewing; Saccharomyces cerevisiae; awamori; breeding; comparative genomics; hibiscus yeast; liquor flavors.

Since flavors of alc. beverages produced in fermentation process are affected mainly by yeast metabolism, the isolation and breeding of yeasts have contributed to the alc. beverage industry. To produce awamori, a traditional spirit (distilled alc. beverage) with unique flavors made from steamed rice in Okinawa, Japan, it is necessary to optimize yeast strains for a diversity of tastes and flavors with established qualities. Two categories of flavors are characteristic of awamori; initial scented fruity flavors and sweet flavors that arise with aging. Here we isolated a novel strain of Saccharomyces cerevisiae from hibiscus flowers in Okinawa, HC02-5-2, that produces high levels of alc. The whole-genome information revealed that strain HC02-5-2 is contiguous to wine yeast strains in a phylogenic tree. This strain also exhibited a high productivity of 4-vinyl guaiacol (4-VG), which is a precursor of vanillin known as a key flavor of aged awamori. Although conventional awamori yeast strain 101-18, which possesses the FDC1 pseudogene does not produce 4-VG, strain HC02-5-2, which has the intact PAD1 and FDC1 genes, has an advantage for use in a novel kind of awamori. To increase the contents of initial scented fruity flavors, such as isoamyl alc. and isoamyl acetate, we attempted to breed strain HC02-5-2 targeting the L-leucine synthetic pathway by conventional mutagenesis. In mutant strain T25 with Lleucine accumulation, we found a hetero allelic mutation in the LEU4 gene encoding the Gly516Ser variant a-isopropylmalate synthase (IPMS). IPMS activity of the Gly516Ser variant was less sensitive to feedback inhibition by L-leucine, leading to intracellular L-leucine accumulation. In a laboratory-scale test, awamori brewed with strain T25 showed higher concentrations of isoamyl alc. and isoamyl acetate than that brewed with strain HC02-5-2. Such a combinatorial approach to yeast isolation, with wholegenome anal. and metabolism-focused breeding, has the potentials to vary the quality of alc. beverages.

Frontiers in Genetics published new progress about Brewing. 106-32-1 belongs to class esters-buliding-blocks, name is Ethyl octanoate, and the molecular formula is C10H20O2, Name: Ethyl octanoate.

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

He, Xi published the artcileConstruction and analysis of a food-grade Lactiplantibacillus plantarum esterase/lipase overexpression system, HPLC of Formula: 123-29-5, the main research area is food grade Lactiplantibacillus esterase lipase overexpression system.

Lactiplantibacillus plantarum (L. plantarum) is widely used in the food industry, especially in meat fermentation and dairy processing, due to its lipase and esterase activities. In this study, lp_1002 from L. plantarum WCFS1 was cloned into the food-grade gene expression vector pMG36n, with nisin used as a selective marker. Furthermore, pMG36n- lp_1002 was retransformed into L. plantarum WCFS1, and lp_1002 was overexpressed in the newly constructed L. plantarum WCFS1 strain. Moreover, recombinant Lp_1002 showed the characteristics of both lipase and esterase. The results from hydrolysis of p-nitrophenylphosphate (pNPP) and triglycerides showed that the hydrolysis activities of the recombinant Lp_1002 were 420% and 360% higher than that of the original strain, resp. In addition, the results of wine MLF fermentation suggest that the recombinant strain significantly reduced the contents of Et esters, acetate esters and other types of esters, which affected wine aroma during brewing. Therefore, the recombinant strain has great application potential in food fermentation

LWT–Food Science and Technology published new progress about Brewing. 123-29-5 belongs to class esters-buliding-blocks, name is Ethyl nonanoate, and the molecular formula is C11H22O2, HPLC of Formula: 123-29-5.

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

Alavi, Seyed Ebrahim published the artcileOptimized Methods for the Production and Bioconjugation of Site-Specific, Alkyne-Modified Glucagon-Like Peptide-1 (GLP-1) Analogs to Azide-Modified Delivery Platforms Using Copper-Catalyzed Alkyne-Azide Cycloaddition, Application of 1-(9H-Fluoren-9-yl)-3-oxo-2,7,10,13,16,19-hexaoxa-4-azadocosan-22-oic acid, the main research area is glucagon like peptide 1 analog alkyne azide cycloaddition.

This study aimed to develop and optimize chemistries to produce alkyne-modified glucagon-like peptide-1(7-36)-amide (GLP-1(7-36)-NH2) libraries, which could be rapidly and efficiently conjugated to other components and screened to identify compounds with the best drug delivery properties, as potential treatments for type 2 diabetes or obesity. For this purpose, the Lys26 (K26) side-chain, and the amino (N)- and carboxy (C)-termini of a dipeptidyl peptidase 4 (DPPIV)-resistant GLP-1 sequence (GLP-1(7-36;A8G)-NH2), were modified with an alkyne (4-pentynoic acid or propiolic acid). These analogs were characterized with respect to human GLP-1 receptor (hGLP-1R) agonist activity, effects on cell viability and human serum stability, revealing that these modifications maintained low (N-terminal; EC50 1.5 x 10-9 M) to subnanomolar (C-terminal and K26, ~4 x 10-10 M) agonist activity toward hGLP-1, had no effect on cell viability, and for the N-terminal and K26 modifications, increased human serum proteolytic stability (t1/2 > 24 h). Copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction conditions were investigated using the C-terminal modified GLP-1 analog and an azide-modified model lipid peptide, with respect to the effects of altering the azide/alkyne ratio, cosolvents, temperature, reducing agents, Cu(I)-stabilizing ligand, copper source, and the concentrations of reagents/reactants, in order to identify general conditions that provide fast reactions and high yields. A 1:2 azide-alkyne (lipid:GLP-1 peptide) and 4:1 sodium ascorbate/copper sulfate molar ratio in 65% volume/volume DMSO-water at room temperature, in the absence of Cu(I)-stabilizing ligands (THPTA or L-histidine) and buffers (phosphate, pH 7), provided the best yields. This work reports a library of characterized GLP-1 analogs and chemistries for their attachment to other species, providing useful tools to improve GLP-1 delivery and pharmacol. (e.g., through conjugation to other species that lower blood glucose, increase the duration of action, or enable delivery via a nonparenteral route).

Bioconjugate Chemistry published new progress about Buffers. 882847-32-7 belongs to class esters-buliding-blocks, name is 1-(9H-Fluoren-9-yl)-3-oxo-2,7,10,13,16,19-hexaoxa-4-azadocosan-22-oic acid, and the molecular formula is C28H37NO9, Application of 1-(9H-Fluoren-9-yl)-3-oxo-2,7,10,13,16,19-hexaoxa-4-azadocosan-22-oic acid.

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

Zang, Jinhong published the artcileIdentification of characteristic flavor and microorganisms related to flavor formation in fermented common carp (Cyprinus carpio L.), Category: esters-buliding-blocks, the main research area is flavor microorganism fermented Cyprinus carpio; Cyprinus carpio; Fermented fish; Flavor; Metabolic network; Metagenomic; Microorganisms.

Microbial metabolism is crucial for the flavor development of traditional Suanyu. A total of 21 characteristic volatile compounds of Suanyu were identified according to GC-MS combined with GC-O anal. HCA results indicated that the whole fermentation process could be divided into three stages: raw material (fresh), initial fermentation (0-2 wk) and the late fermentation (2-4 wk). Moreover, nine flavor markers in different fermentation stages were revealed using the OPLS-DA model and VIP values. Furthermore, metagenomic sequencing was used to analyze the possible formation pathways of the characteristic flavor compounds and identify the key microorganisms related to flavor formation at the gene level. The top 10 bacterial genera associated with flavor formation were Staphylococcus, Enterococcus, Vibrio, Kocuria, Lactobacillus, Macrococcus, Streptococcus, Enterobacter, Lactococcus and Pediococcus, accounting for large parts of flavor formation of fermented Suanyu. This study is helpful to elucidate the different metabolic roles of microorganisms in flavor formation during fermentation

Food Research International published new progress about Candida. 41114-00-5 belongs to class esters-buliding-blocks, name is Ethyl pentadecanoate, and the molecular formula is C17H34O2, Category: esters-buliding-blocks.

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

Chen, Xiao published the artcileLipase-catalyzed modification of milk fat: A promising way to alter flavor notes of goat milk products, Recommanded Product: Ethyl nonanoate, the main research area is lipase milk fat modification fatty acid synthesis.

The rancid and tart off-flavor of goat milk limits the popularization of its associated products. In this study, a two-step enzymic catalysis method was proposed to generate new aromatic notes that could alter the neg. flavor perception of goat milk products. The goat milk fat was first hydrolyzed to prepare fatty acids (FFAs) as substrates, and then esterification was carried out for the synthesis of esters with pleasant notes. In the first step, the FFAs were sufficiently released, accounting for 97.5% of the volatile fraction. In the final reconstituted goat milk product, esters with sweet, floral, and fruity-like notes occupied more than 65% of the total volatile compounds, while the abundance of fatty acids characterized by unpleasant odor decreased by 75%. Especially, 4-methyloctanoic acid, one of the FFAs responsible for the “”goaty”” flavor, was not detected under the substrate molar ratio of 0.4. Moreover, the performance of four com. lipases was investigated and compared during the first step. Lipozyme TL IM was the most efficient in the catalysis of lipid hydrolysis at 60°C and pH 8.0. The two-step lipase-catalyzed product provided a sweet and fruity note to goat milk products and reduced the intensity of the unpleasant “”goaty”” flavor.

LWT–Food Science and Technology published new progress about Candida. 123-29-5 belongs to class esters-buliding-blocks, name is Ethyl nonanoate, and the molecular formula is C11H22O2, Recommanded Product: Ethyl nonanoate.

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

Cai, Zhenping published the artcileOne-pot production of diethyl maleate via catalytic conversion of raw lignocellulosic biomass, Recommanded Product: Ethyl 4-oxopentanoate, the main research area is lignocellulosic biomass catalytic conversion diethyl maleate production.

The conversion of lignocellulose into a value-added chem. with high selectivity is of great significance but is a big challenge due to the structural diversities of biomass components. Here, we have reported an efficient approach for the one-step conversion of raw lignocellulose into di-Et maleate by the polyoxometalate ionic liquid [BSmim]CuPW12O40 in ethanol under mild conditions. The results reveal that all of the fractions in biomass, i.e., cellulose, lignin and hemicellulose, were simultaneously converted into di-Et maleate (DEM), achieving a 329.6 mg g-1 yield and 70.3% selectivity from corn stalk. Importantly, the performance of the ionic liquid catalyst [BSmim]CuPW12O40 was nearly twice that of CuPW12O40, which can be attributed to the lower incorporation of the Cu2+ site in [BSmim]CuPW12O40. Hence, this process opens a promising route for producing bio-based bulk chems. from raw lignocellulose without any pretreatment.

Green Chemistry published new progress about Bagasse. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Recommanded Product: Ethyl 4-oxopentanoate.

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