Category: esters-buliding-blocks

Balmaseda, Aitor published the artcileImpact of changes in wine composition produced by non-Saccharomyces on malolactic fermentation, Application of Ethyl octanoate, the main research area is Oenococcus Torulaspora Saccharomyces wine malolactic fermentation; Malolactic fermentation; Non-Saccharomyces; Oenococcus oeni; Wine.

Non-Saccharomyces yeasts have increasingly been used in vinification recently. This is particularly true of Torulaspora delbrueckii and Metschnikowia pulcherrima, which are inoculated before S. cerevisiae, to complete a sequential alc. fermentation This paper aims to study the effects of these two non-Saccharomyces yeasts on malolactic fermentation (MLF) carried out by two strains of Oenococcus oeni, under cellar conditions. Oenol. parameters, and volatile and phenolic compounds were analyzed in wines. The wines were tasted, and the microorganisms identified. In general, non-Saccharomyces created more MLF friendly conditions, largely because of lower concentrations of SO2 and medium chain fatty acids. The most favorable results were observed in wines inoculated with T. delbrueckii, that seemed to promote the development of O. oeni and improve MLF performance.

International Journal of Food Microbiology published new progress about Alleles. 106-32-1 belongs to class esters-buliding-blocks, name is Ethyl octanoate, and the molecular formula is C10H20O2, Application of Ethyl octanoate.

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

Bergal, Mathilde published the artcileIn vitro testing strategy for assessing the skin sensitizing potential of “”difficult to test”” cosmetic ingredients, Application of Hexyl 2-hydroxybenzoate, the main research area is skin sensitization cosmetic.

Before placing a new cosmetic ingredient on the market, manufacturers must establish its safety profile, in particular assessing the skin sensitization potential, which is a mandatory requirement for topical applications. Since the ban on animal testing in Europe, and its extension to many parts of the world, a battery of in vitro tests covering the key steps of the Adverse Outcome Pathway (AOP) for skin sensitization is recommended. To date, three in vitro methods are validated in the OECD guidelines (442C, 442D, 442E), and many others are under validation by OECD (2019) and ECVAM. However, there is still no official strategy. Some industrial manufacturers have proposed in vitro strategies with good predictivity, but their studies were mainly based on the testing of simple and “”easy to test”” substances. This work therefore focused on “”difficult to test”” ingredients with particular physicochem. properties (i.e. poorly water-soluble components) or with particular intrinsic properties placing them outside the applicability domains of most in vitro models (irritants or cytotoxic like surfactants, complex substances). Furthermore a particular focus was made on weak to moderate sensitizers. The objective was to develop a robust, quick and straightforward testing strategy enabling the evaluation of the skin sensitization potential of “”difficult to test”” ingredients. In this context, four in vitro test models were used: three validated methods and the Sens-Is assay, currently in the work plan of the OECD, chosen for its ability to overcome solubility issues and to discriminate irritants from sensitizers. 25 ingredients with particular physicochem. properties were evaluated, chosen among pos. or neg. sensitizers according to in vivo data (M&K and/or LLNA). Such ingredients, including cleansers, solubilizers, emulsifiers, emollients, active ingredients, preservatives, and antioxidants are indeed essential constituents of cosmetic and dermopharmaceutical formulations. The results anal. on each in vitro test demonstrated that the DPRA model was the less predictive on the chosen ingredients, resulting especially in many false neg. responses compared to animal studies, or being unsuited to the mode of action of the selected ingredients. On the contrary, the Sens-Is assay revealed a real capability to discriminate sensitizers from non-sensitizers. The two other models, KeratinoSensTM and h-CLAT, showed a lower ability to classify the materials correctly than in previously published studies, linked to the particular physicochem. and intrinsic properties of the chosen ingredients and the applicability domains of these in vitro tests. The KeratinoSensTM model tended to overestimate the sensitization potential of the tested ingredients, whereas the h-CLAT model tended to underestimate the sensitizers. Based on these results a new sequential testing strategy was set up combining 1 to 3 models to cover the main key events of the skin sensitization AOP. Sens-Is model, assessing the first two AOP Key Events with consideration of the ingredient dermal penetration, is chosen as a starting point. The approach is completed, depending on the first response, by the h-CLAT model, assessing Key Event 3, and then potentially KeratinoSensTM assessing Key Event 2, but with a more direct application mode. This new testing strategy increases the accuracy to 88% on the selected ingredients and minimizes the risk of a false neg. conclusion, which is crucial from the perspective of the ingredients′ users and cosmetic consumers.

Toxicology In Vitro published new progress about Allergy. 6259-76-3 belongs to class esters-buliding-blocks, name is Hexyl 2-hydroxybenzoate, and the molecular formula is C13H18O3, Application of Hexyl 2-hydroxybenzoate.

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

Tourneix, Fleur published the artcileAssessment of a defined approach based on a stacking prediction model to identify skin sensitization hazard, Product Details of C13H18O3, the main research area is defined approach stacking model skin sensitization sensitizer safety assessment; Defined approach; Hazard identification; In silico; In vitro; Risk assessment; Skin sensitization.

Skin sensitization is an important toxicol. endpoint in the safety assessment of chems. and cosmetic ingredients. Driven by ethical considerations and European Union (EU) legislation, its assessment has progressed from the reliance on traditional animal models to the use of non-animal test methods. It is generally accepted that the assessment of skin sensitization requires the integration of various non-animal test methods in defined approaches (DAs), to cover the mechanistic key events of the adverse outcomes pathway (AOP) (OECD, 2014). Several case studies for DAs predicting skin sensitization hazard or potency have been submitted to the OECD, including a stacking meta-model developed by L’Oreál Research & Innovation (OECD, 2017b; Del Bufalo et al., 2018; Nocairi et al., 2016). The present study evaluated the predictive performance of the defined approach integrating a stacking meta-model incorporating in silico, in chemico and in vitro assays, using the Cosmetics Europe (CE) skin sensitization database. Based on the optimized prediction cut-offs, the defined approach provided a hazard prediction for 97 chems. with a sensitivity of 91%, a specificity of 76% and accuracy of 86% (kappa of 0.67) against human skin sensitization hazard data and a sensitivity of 85%, specificity of 91% and accuracy of 87% (kappa of 0.67) against Local Lymph Node Assay (LLNA) hazard data. A comparison of the in vivo LLNA with human hazard data for the same 97 chems. showed a sensitivity of 92%, specificity of 51% and accuracy of 78% (kappa of 0.48). Thus, the defined approach showed a higher degree of concordance, as compared to the LLNA for predicting human skin sensitization hazard. Moreover, a comparison with the six DAs selected for evaluation of their predictivity in the study by Kleinstreuer et al. (2018) showed a similar high accuracy of 86% for 97 overlapping chems. The next step will be an independent evaluation of the DA for its integration in the performances based test guidelines for skin sensitization.

Toxicology In Vitro published new progress about Allergy. 6259-76-3 belongs to class esters-buliding-blocks, name is Hexyl 2-hydroxybenzoate, and the molecular formula is C13H18O3, Product Details of C13H18O3.

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

Brown, Lindsay E. published the artcileCrotalus atrox venom-induced cellular toxicity: Early wound progression involves reactive oxygen species, COA of Formula: C24H14Cl2O7, the main research area is Crotalus venom cytotoxicity wound reactive oxygen species; Crotalus atrox; anoikis; antioxidants; inflammation; reactive oxygen species.

Understanding the mechanisms that produce cellular cytotoxicity is fundamental in the field of toxicol. Cytotoxic stimuli can include organic toxins such as hemorrhagic snake venom, which can lead to secondary complications such as the development of necrotic tissue and profuse scarring. These clin. manifestations mimic cytotoxic responses induce by other organic compounds such as organic acids. We used hemorrhagic snake venom and human embryonic kidney cells (HEK 293T) as a model system to better understand the cellular responses involved in venom induced cytotoxicity. Cells stimulated with Crotalus atrox (CA) (western diamondback) venom for 4 or 10 h demonstrated significant cytotoxicity. Results from 2′,7′-Dichlorodihydrofluorescein diacetate (H2DCF-DA) assays determine CA venom stimulation induces a robust production of reactive oxygen species (ROS) over a 3-h time course. In contrast, pretreatment with polyethylene glycol (PEG)-catalase or N-acetyl cysteine (NAC) prior to CA venom stimulation significantly blunted H2DCFDA fluorescence fold changes and showed greater cytoprotective effects than cells stimulated with CA venom alone. Pre- incubating HEK293T cells with the NADPH oxidase (NOX) pan-inhibitor VAS2870 prior venom stimulation significantly minimized the venom-induced oxidative burst at early timepoints (≤2 h). Collectively, our experiments show that pre-application of antioxidants reduces CA venom induce cellular toxicity. This result highlights the importance of ROS in the early stages of cytotoxicity and suggests muting ROS production in noxious injuries may increase pos. clin. outcomes.

Journal of Applied Toxicology published new progress about Anoikis. 2044-85-1 belongs to class esters-buliding-blocks, name is 2′,7′-Dichloro-3-oxo-3H-spiro[isobenzofuran-1,9′-xanthene]-3′,6′-diyl diacetate, and the molecular formula is C24H14Cl2O7, COA of Formula: C24H14Cl2O7.

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

Yilmaz, Bilal published the artcileAnalysis of fatty acid compositions of apricot kernel oils for cosmetic purpose with gas chromatography-mass spectrometry method, HPLC of Formula: 929-77-1, the main research area is cosmetic apricot kernel oil fatty acid composition GCMS.

In this study, fatty acid compositions of apricot kernel oils for cosmetic purpose were analyzed. Qual. and quant. anal. of fatty acids in apricot kernel oils were made by using gas chromatog.-mass spectrometry (GC-MS). In this anal., apricot kernel oils -which trademarked Karden, Organix and Biovitalssupplied from a herbalist were used. The oils were converted to the Me ester with KOH hydrolysis. Just after the derivatization process, the oils were analyzed by GC-MS. In conclusion, it was determined that these apricot kernel oils which belong to three different trademarks have a similar fatty acid profile, however, there was no specific standard between them.

International Journal of Pharmacognosy (Panchkula, India) published new progress about Apricot. 929-77-1 belongs to class esters-buliding-blocks, name is Methyl docosanoate, and the molecular formula is C23H46O2, HPLC of Formula: 929-77-1.

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

Shao, Yuanyang published the artcileExploration on varying patterns of morphological features and quality of armeniacae semen amarum in rancid process based on colorimeter, electronic nose, and GC/MS coupled with human panel, COA of Formula: C9H10O2, the main research area is armeniacae semen amarum colorimeter electronic nose GCMS; armeniacae semen amarum; colorimeter; electronic nose; gas chromatography–mass spectrometry; human panel.

In recent years, the domestic and international trade volumes of Chinese medicinal materials (CMMs) keep increasing. By the end of 2019, the total amount of exported CMMs reached as high as US $1.137 billion, while imported was US $2.155 billion. A stable and controllable quality system of CMMs apparently becomes the most important issue, which needs multifaceted collaboration from harvesting CMMs at a proper season to storing CMMs at a proper temperature However, due to imperfect storage conditions, different kinds of deteriorations are prone to occur, for instance, get moldy or rancid, which not only causes a huge waste of CMM resources but also poses a great threat to clin. medication safety and public health. The key issue is to quickly and accurately distinguish deteriorated CMM samples so as to avoid consuming low-quality or even harmful CMMs. However, some attention has been paid to study the changing quality of deteriorated CMMs and a suitable method for identifying them. In this study, as a medicine and food material which easily becomes rancid, armeniacae semen amarum (ASA) was chosen as a research objective, and exptl. ASA samples of different rancidness degrees were collected. Then, various kinds of anal. methods and technologies were applied to explore the changing rules of ASA quality and figure out the key indicators for the quality evaluation of ASA in the rancid process, including the human panel, colorimeter, electronic nose, and GC/MS. This study aims to analyze the correlation between the external morphol. features and the inner chem. compounds, to find out the specific components from ”quant. change” to ”qual. change” in the process of ”getting rancid,” and to discover the dynamic changes in the aforementioned key indicators at different stages of rancidness. The results showed since ASA samples began to get rancid with the extension of storage time, morphol. features, namely, surface color and smell, changed significantly, and the degree of rancidness further deepened at the same time. Based on macroscopic identification accomplished via the human panel, ASA samples with varying degrees of rancidness were divided into four groups. The result of colorimeter anal. was in agreement with that of the human panel, as well as the determination of the amygdalin content and peroxide value. Moreover, there were obvious differences in the amygdalin content and peroxide value among ASA samples with different rancidness degrees. With a higher degree of rancidness, the content of amygdalin decreased, while the peroxide value increased significantly. The rancidness degree of ASA has a neg. correlation with the amygdalin content and a pos. correlation with the peroxide value. The newly discovered nonanal and 2-bromopropiophenone in rancid ASA samples may be the key components of ”rancidity smell,” and these two components would be the exclusive components that trigger ”quant. change” to ”qual. change” in the process of rancidness of ASA. This study sheds light on studying the internal mechanism of ”rancidness” of CMMs and provides an important basis for the effective storage and safe medication of easy-to-get rancid herbs, and it also plays an important foundation for the establishment of a stable and controllable quality system for CMMs.

Frontiers in Pharmacology published new progress about Apricot. 140-11-4 belongs to class esters-buliding-blocks, name is Benzyl acetate, and the molecular formula is C9H10O2, COA of Formula: C9H10O2.

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

Singh, P. published the artcileA Solvent-tolerant Alkaline Lipase from Bacillus sp. DM9K3 and Its Potential Applications in Esterification and Polymer Degradation, Computed Properties of 106-32-1, the main research area is Lipase Bacillus Esterification.

Abstract: Solvent-tolerant lipase produced by Bacillus sp. DM9K3 has been isolated from the hypersaline area, White Rann of Kachchh, Gujarat, India. The strain initially showed lipase activity of 11.1 U/mL in a basal medium which increased to 52.0 U/mL under optimized culture conditions. Bacillus sp. DM9K3 exhibited stability at 7% salinity, pH 9.0 and 50°C. The extracellular lipase was partially purified by acetone precipitation followed by DEAE-cellulose resulting in 39-fold purification with 40% yield. Metals ions such as Mg2+, Ca2+ and K+ showed enhanced enzyme activity. EDTA did not have a significant effect on activity suggesting that lipase is not metalloenzyme. The lipase under study showed the highest activity when palmitate (C16) was used as a substrate and was also highly stable in organic solvents such as cyclooctane and benzene. The partially purified enzyme was immobilized for increasing the efficiency of the Et caprylate (an orange flavored ester) synthesis in the presence of cyclooctane. Addnl., lipase of Bacillus sp. DM9K3 was explored for biodegradation of polycaprolactone microspheres and showed promising results for potential applications in drug delivery system.

Applied Biochemistry and Microbiology published new progress about Bacilli. 106-32-1 belongs to class esters-buliding-blocks, name is Ethyl octanoate, and the molecular formula is C10H20O2, Computed Properties of 106-32-1.

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

Feng, Junfeng published the artcileCollaborative Conversion of Biomass Carbohydrates into Valuable Chemicals: Catalytic Strategy and Mechanism Research, Name: Ethyl 4-oxopentanoate, the main research area is biomass carbohydrate valuable chem catalytic strategy mechanism; collaborative conversion; levulinates; lignocellulose; zeolite.

Levulinate is one of the high added-value biomass-derived chems. that is primarily produced from hexoses in cellulose and hemicellulose. Producing levulinate from pentoses in hemicellulose that is extensively distributed in biomass is still highly challenging. In this study, biomass materials and carbohydrates (including cellulose, xylan, glucose, fructose, and xylose) were collaboratively converted into levulinates efficiently over various zeolites with ethanol/dimethoxymethane as cosolvents. The key process for converting pentoses into levulinates is the synthesis of intermediates (furfural) into alkoxy Me furfural via electrophilic substitution or their conversion into furfuryl alc. via in situ hydrogenation. The substitution was achieved by the synergic effect between bifunctional catalysts and cosolvents, which promotes conversion of furfural into alkoxy Me furfural via the electrophilic addition of alkoxy Me radicals. Hydrogenation of furfural into furfuryl alc. was impelled by the cooperative process between in situ generated H-donor from alc. solvents and zeolite catalysts. Moreover, a favorable yield of 21.05 mol % of levulinates was achieved by simultaneous and collaborative conversion of cellulose and hemicellulose with the one-pot process using ethanol/dimethoxymethane as a cosolvent and the zeolite with B and L acid sites as a catalyst.

Journal of Agricultural and Food 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, Name: Ethyl 4-oxopentanoate.

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

Liu, Chenlu published the artcileEsterification of levulinic acid into ethyl levulinate catalyzed by sulfonated bagasse-carbonized solid acid, Related Products of esters-buliding-blocks, the main research area is levulinic acid esterification ethyl levulinate sugarcane bagasse sulfonated carbon.

A sulfonic carbon-based catalyst (C-SO3H) was successfully prepared by sulfonating incompletely carbonized sugarcane bagasse. The optimized catalyst of high activity in the esterification of levulinic acid (LA) with ethanol was produced under sulfonation at 150 °C for 15 h with a 75 mL/g sulfonation ratio. The prepared catalysts were characterized by X-ray powder diffraction (XRD), Fourier transform IR (FTIR) anal., SEM (SEM), and elemental anal. (EA). The bagasse-carbonized catalyst was porous, and the porous structure remained unchanged after sulfonation treatment. Moreover, the introduced acidic group was the catalytic center. A high yield of Et levulinate (ELA) of 88.2% was obtained at 120 °C for 9 h. The sulfonic carbon-based catalyst could be reused at least five times and still exhibited great stability. The application of the sulfonic carbon-based catalyst was not only the effective use of biomass resources but also promoted the production of various high value chems.

BioResources 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, Related Products of esters-buliding-blocks.

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

Xiao, Ye published the artcileSolid acid catalysts produced by sulfonation of petroleum coke: Dominant role of aromatic hydrogen, HPLC of Formula: 111-11-5, the main research area is sulfonated petcoke solid acid catalyst preparation esterification; Aromatic hydrogen; Esterification; Petroleum coke; Solid acid; Sulfonation.

Carbon based solid waste materials have been intensively investigated for the preparation of solid acid catalysts through sulfonation, but the acidity varies significantly depending on the material. In this study, the role of aromatic hydrogen in sulfonation with concentrated H2SO4 was investigated using petroleum coke (petcoke), graphite, and biochar as the carbon materials. Through ball milling and calcination, the amount of aromatic hydrogen on the petcoke could be increased or decreased, resp. After sulfonation at 80°C with concentrated H2SO4, the produced acidity (i.e., -SO3H groups) increased as the amount of aromatic hydrogen increased from essentially no acidity on graphite to 0.55 mmol/g on biochar and 1.25 mmol/g on petcoke (particle sizes of 45-90μm) indicating the importance of aromatic hydrogen during sulfonation. Calcination (350°C for 1 h) of the petcoke before sulfonation decreased the acidity to 0.59 mmol/g, while ball milling (with isopropanol and silica for 24 h) increased the acidity to 3.73 mmol/g. The sulfonated petcoke samples were used as catalysts for the esterification reaction between octanoic acid and methanol at 60°C and the turnover frequencies were 48-85 h-1. The results give insights on the preparation of solid acid catalysts from carbon materials and highlight the application of petcoke without activation as a feedstock for esterification catalysts.

Chemosphere published new progress about Acidity. 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