Month: December 2022

Zhang, Ning published the artcileChanges of amygdalin and volatile components of apricot kernels during the ultrasonically-accelerated debitterizing, Related Products of esters-buliding-blocks, the main research area is amygdalin apricot kernel ultrasonic debitterizing; Amygdalin; Apricot kernels; Debitterizing; Epimerization; Volatile components.

Ultrasound has been regarded as an efficient novel technique for debitterizing of the apricot kernels, but its influence is severely concerned on the possible epimerization of D-amygdalin to the L-amygdalin, a more potentially toxigenic compound Considering this, the experiments were conducted to investigate the epimerization of D-amygdalin and the volatile components in the debitterizing water, which were separated and identified by the high performance liquid chromatog. (HPLC) and gas chromatog. with a mass spectrometer (GC-MS), resp. The results indicate that the ultrasonically-debitterizing did not cause the epimerization of D-amygdalin to the L-amygdalin, while the procedure can be greatly accelerated due to the rapid mass transfer and degradation of D-amygdalin induced by ultrasound irradiation In addition, the water from the ultrasonically-debitterizing of apricot kernels exerted more aromas compared with that of the conventional debitterizing, which might have more applications about this kind of water. In a word, ultrasound can be safely applied in the debitterizing industry of apricot kernels.

Ultrasonics Sonochemistry published new progress about Ultrasonication. 140-11-4 belongs to class esters-buliding-blocks, name is Benzyl acetate, and the molecular formula is C9H10O2, Related Products of esters-buliding-blocks.

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

O’Malley, Elissa published the artcilePer capita loads of organic UV filters in Australian wastewater influent, HPLC of Formula: 71617-10-2, the main research area is wastewater organic UV filter Australia; Australia; Census; Influent; Sunscreen; UV filter; Wastewater.

Per capita loads of six UV filters were estimated in wastewater influent samples from 36 wastewater treatment plants in Australia collected over a weekend period during the 2016 Australian Census. Of the analyzed samples, 99% contained at least one of the target compounds Ph benzimidazole sulfonic acid (PBSA) was the most prevalent (99%), followed by benzophenone 4 (BP4) (97%), benzophenone 3 (BP3) (87%), benzophenone 1 (BP1) (84%), 4-methylbenzylidene camphor (4-MBC) (22%) and isoamyl 4-methoxycinnamate (IMC) (1.5%). The highest concentrations were 3780 and 5070 ng L-1 for PBSA and BP4, resp. Total per capita UV filter loads in influent across all plants were calculated using population data from the Australian Census and ranged from 0.21 to 3.4 mg day-1 person-1. Notably, a relationship was found between latitude and total per capita daily mass load of UV filters with an increase in mass load from southern to northern catchments. Compared to international studies, mass loads were generally similar with higher loads of BP4 found in Australia. This study provides insight into the occurrence of UV filters in influent wastewater from across Australia and provides the first comprehensive nationwide baseline of UV filter loads.

Science of the Total Environment published new progress about Solar radiation. 71617-10-2 belongs to class esters-buliding-blocks, name is Isopentyl 3-(4-methoxyphenyl)acrylate, and the molecular formula is C15H20O3, HPLC of Formula: 71617-10-2.

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

Bernardo, Naissa Previde published the artcileVolatile Composition of Sparkling Wines of cv. Chardonnay Cultivated under Different Training Systems in Serra da Mantiqueira (Brazil), SDS of cas: 6259-76-3, the main research area is sparkling wine training system volatile composition; GC-MS; GDC; HS-SPME; aroma; crop; lyre.

The grapevine is a climbing plant and allows for the manipulation of vegetative canopies to change the microclimate and exposure of leaves and clusters to solar radiation, affecting the primary and secondary metabolisms of plants. Thus, this work aimed to evaluate how the lyre and Geneva double-curtain (GDC) training systems could contribute to the volatile composition of sparkling wines in replicates of vinifications carried out in the Serra da Mantiqueira (Brazil) in two consecutive summer harvests (2017 and 2018). Fifty-four free volatile compounds were identified by HS-SPME/GC-MS in the wines in both systems and vintages. Multivariate anal. differentiated the vintages in component 1 (22.7%) and the training systems in component 2 (7.1%). The crops were differentiated by aldehydes in 2017 and in 2018 by isoamyl acetate ester, probably derived from the amino acid leucine, the season having been more humid, with lower temperatures and less radiation. For the training systems, besides the alc. compounds, the GDC was differentiated by the terpenoid compounds geranylacetone and β-damascenone, which may contribute more pleasant aromas to sparkling wines. This work promotes addnl. research and enables winegrowers, through the management of their vineyards, to achieve sparkling wines with different volatile compositions

Foods published new progress about Soils, vineyard. 6259-76-3 belongs to class esters-buliding-blocks, name is Hexyl 2-hydroxybenzoate, and the molecular formula is C13H18O3, SDS of cas: 6259-76-3.

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

Zhang, Huimin published the artcileThe effect of the LC mixtures with the different clearing point on temperature dependence of the electro-optical properties of polymer dispersed liquid crystals, Application In Synthesis of 142-90-5, the main research area is polymer dispersed liquid crystal clearing point electro optical property.

Two groups of polymer dispersed liquid crystals (PDLCs) have been studied, results indicated, when the liquid crystals (LCs) and the UV monomers before curing in the preparation had poor miscibility, the PDLCs showed poor electro-optical properties. Then, we obtained a series of LC mixtures based on E8 and B001, the clearing point of which changed from 71.6°C to 142.0°C. The further study on the effect of temperature on the electro-optical properties of PDLCs indicated that PDLCs with high temperature resistance may be obtained by increasing the clearing point of LCs coupled with manipulating other LC parameters.

Molecular Crystals and Liquid Crystals published new progress about Liquid crystals. 142-90-5 belongs to class esters-buliding-blocks, name is Dodecyl 2-methylacrylate, and the molecular formula is C16H30O2, Application In Synthesis of 142-90-5.

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

Han, Ge published the artcileImpacts of different altitudes and natural drying times on lipolysis, lipid oxidation and flavour profile of traditional Tibetan yak jerky, Quality Control of 111-11-5, the main research area is lipid oxidation lipolysis volatile compound physicochem property; Free fatty acids; Sensory characteristics; Volatile compounds; Yak jerky.

The impact of different altitudes on the physicochem. properties, lipolysis, lipid oxidation, volatile compound formation and sensory evaluation of traditional Tibetan dried yak jerky during natural drying was investigated. High altitude (HA) yak jerky showed higher percentages of unsaturated fatty acids and thiobarbituric acid reactive substances than low altitude (LA) yak jerky during natural drying (P < 0.05). The percentages of polyunsaturated fatty acids and monounsaturated fatty acids decreased during natural drying, whereas that of saturated fatty acids increased (P < 0.05). A total of 54 volatile compounds were identified and quantified, and there were higher contents of volatile compounds in HA yak jerky than in LA jerky, which were mainly derived from lipid oxidation Principal component anal. showed that the volatile compounds associated with the highest overall acceptability in HA yak jerky were hexanal, nonanal, (E)-2-nonenal, 1-hexanol, 2-heptanone, 2-methyl-3-octanone and 6-methyl-5-hepten-2-one. The volatile compounds associated with the highest overall acceptability for yak jerky with a longer natural drying time were hexane, 1-octanol, 2-ethylhexanol, heptanal, (E)-2-hexenal, (E)-2-octenal, 1-octen-3-ol and 2,3-octanedione. According to the sensory evaluations, HA yak jerky with a natural drying time of 75 d tends to be more popular. Meat Science published new progress about Lipid oxidation. 111-11-5 belongs to class esters-buliding-blocks, name is Methyl octanoate, and the molecular formula is C9H18O2, Quality Control of 111-11-5.

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

Su, Xueqian published the artcileAroma characterization of regional Cascade and Chinook hops (Humulus lupulus L.), HPLC of Formula: 111-11-5, the main research area is beta myrecene methyl octanoate geraniol linalool Humulus aroma quality; 2-Octanol (PubChem CID: 20083); Aroma chemistry; Aroma extract dilution analysis (AEDA); Gas chromatography-mass spectrometry-olfactometry (GC-MS-O); Geraniol (PubChem CID: 637566); Hops; Linalool (PubChem CID: 6549); Methyl octanoate (PubChem CID: 8091); Stable isotope dilution analysis (SIDA); Standard addition method (SAM); cis-β-Farnesene (PubChem CID: 5317319); α-Humulene (PubChem CID: 6508206); β-Caryophyllene (PubChem CID: 5281522); β-Myrcene (PubChem CID: 31253).

Aroma compounds in Cascade and Chinook hops harvested from multiple Virginia locations were identified by gas chromatog.-mass spectrometry-olfactometry (GC-MS-O) and aroma extract dilution anal. (AEDA). Selected aroma compounds were quantitated by combination of stable isotope dilution anal. (SIDA) and standard addition method (SAM). A total of 33 aroma-active compounds were detected in five samples with β-myrcene, Me octanoate, geraniol and linalool being the predominant compounds based on their high flavor dilution (FD) factors and odor activity values (OAVs). L-Calamenene and germacrene B was the major characteristic component unique to Cascade and Chinook variety, resp. Principal component anal. (PCA) showed distinctive aroma profiles for all samples except for Blacksburg and Petersburg Cascade. Hierarchical cluster anal. (HCA) reflected the higher contents of most aroma-active compounds in Meadow view Cascade and Chinook when compared to their counterparts. The significant variations suggested the potential influences of environmental factors and agronomic practices on hop aroma quality.

Food Chemistry published new progress about Humulus lupulus. 111-11-5 belongs to class esters-buliding-blocks, name is Methyl octanoate, and the molecular formula is C9H18O2, HPLC of Formula: 111-11-5.

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

Kim, Juyeon published the artcileProcess integration and economics of gamma-valerolactone using a cellulose-derived ethyl levulinate intermediate and ethanol solvent, HPLC of Formula: 539-88-8, the main research area is ethyl levulinate gamma valerolactone preparation.

This study combines two catalytic conversion strategies, cellulose to Et levulinate and subsequently to gamma-valerolactone, into an integrated process. The effect of integrating the cellulose-to-Et levulinate and Et levulinate-to-gamma-valerolactone processes on a com. scale is investigated to improve energy efficiency and economics by performing a process simulation study. The conversion strategies show a low energy efficiency of 6.8% using excess ethanol solvent to achieve high yields of Et levulinate and gamma-valerolactone; however, in the integrated process, 0.4% of the ethanol and 30.8% of the cellulose-to-Et levulinate heat requirements are supplied by the Et levulinate-to-gamma-valerolactone process. The min. selling price for the integrated process is estimated to be $5.63/kg gamma-valerolactone, which makes it an economically feasible option for gamma-valerolactone production Finally, we conducted a sensitivity anal. of key parameters (cellulose price, steam price, and ethanol price) highly depending on the min. selling price of gamma-valerolactone.

Energy (Oxford, United Kingdom) published new progress about Heat exchangers. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, HPLC of Formula: 539-88-8.

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

Castro, Gabriel Abranches Dias published the artcileMicrowave-assisted green synthesis of levulinate esters as biofuel precursors using calix[4]arene as an organocatalyst under solvent-free conditions, Formula: C7H12O3, the main research area is levulinate ester sulfonic acid calixarene organocatalyst microwave green synthesis.

Levulinic acid, one of the top 12 value-added chems., can be obtained by the transformation of biomass by acid catalysis. Alkyl levulinate has been widely explored as a precursor for obtaining renewable fuel additives. In this work, the organocatalyst CX4SO3H was employed for the first time as an organocatalyst for levulinic acid esterification reactions. Various parameters, such as the temperature, reaction time, and catalyst load, were investigated. The optimized reaction conditions were a reaction temperature of 80°C (MWI), a reaction time of 2.5 min, a CX4SO3H catalyst load of 1 mol% and solvent-free conditions. Ten different alcs. were evaluated for the synthesis of alkyl levulinate with high yields (ca. 99%), with the exception of tert-Bu alc. (13% yield). The levulinic acid esterification reaction, a type of green chem. reaction, has many advantages such as (i) creation of a new C-O bonds, (ii) water being the sole waste, (iii) 100% carbon economy, (iv) metal- and solvent-free processes, (v) short time and (vi) nontoxic and reusable organocatalysts. These advantages, along with the simple workup procedure, make this efficient protocol a greener alternative to the traditional methods used for the synthesis of levulinate esters to generate biofuels.

Sustainable Energy & Fuels published new progress about Green chemistry. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Formula: C7H12O3.

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

Liu, Shijun published the artcileMultifunctional Ce/ZrSi Catalyst Synergistically Converting 1,4-Pentanediol Derived from Levulinic Acids to Renewable Pentadiene, Computed Properties of 539-88-8, the main research area is ceria zirconium catalyst synergism levulinic acid hydrogenation pentanediol pentadiene.

Here, an innovative approach to produce renewable pentadiene is described: converting levulinic acids to 1,4-pentanediol, followed by dehydration to pentadiene affording 77.5% yield over a multifunctional Ce/ZrSi catalyst. Impressively, a synergistic effect between Ce and ZrSi was disclosed for the direct dehydration, and further transformation was relatively stimulated from the undesirable product 2-methyltetrahydrofuran toward pentadiene. Moreover, the direct dehydration took priority over the pentadiene synthesis among the two reaction pathways.

ACS Sustainable Chemistry & Engineering published new progress about Green chemistry. 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

Zhou, Xin published the artcileEffect of Intermittent Warming on Aroma-Related Esters of Nanguo Pears Through Regulation of Unsaturated Fatty Acid Synthesis After Cold Storage, HPLC of Formula: 111-11-5, the main research area is aroma related ester unsaturated fatty acid synthesis intermittent warming.

Abstract: Cold storage can effectively delay the ripening of Nanguo pears (Pyrus ussuriensis Maxim.). However, the aroma-related esters of Nanguo pears decreased after cold storage. In this study, we aimed to investigate the effect of intermittent warming (IW) treatment on the formation of aroma-related esters and unsaturated fatty acid synthesis from cold stored pears. IW-treated pears were exposed to 20 ± 1°C for 1 day every 20 days during storage at 0 ± 0.5°C, every 21 days was a cycle and a total of 90 days. The pears in control group were stored at 0 ± 0.5°C for 90 days. After this 90-day storage, both groups of pears (control and IW-treated) were transferred to a shelf life of 12 days at room temperature The results showed that, compared with the pears in control group, the productions of aroma-related esters and the expression levels of PuLOX1, PuADH3, and PuAAT1 in IW-treated pears were significantly higher during the shelf life (P < 0.05). We also found that the expression of PuFAD2 and PuFAD3 had significant pos. correlation with the contents of unsaturated fatty acids (P < 0.05). The significantly higher expression levels of PuFAD2 and PuFAD3 in IW-treated pears may have played an important role in the improvement of ester contents (P < 0.05). It could be inferred that IW treatment had an impact on the aroma-related esters of cold-stored Nanguo pears through regulation of unsaturated fatty acid synthesis. Food and Bioprocess Technology published new progress about Gene expression. 111-11-5 belongs to class esters-buliding-blocks, name is Methyl octanoate, and the molecular formula is C9H18O2, HPLC of Formula: 111-11-5.

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