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Bioaromas can be produced by lipases either through their hydrolytic or (trans)esterifying activities. Therefore, this work reports the development of a lipase-catalyzed biotransformed licuri oil, forming volatile ethyl esters with odor notes resembling tropical fruits. Ethyl octanoate formation was promoted when 7.0 % (m/v) Lipozyme 435® was used to convert a grain alcohol:licuri oil mixture (51:49, v/v) at 58ºC and 70 rpm for 6 hours. The biotransformed oil has shown antimicrobial activity against Staphylococcus hominis , S. epidermidis, and Corynebacterium xerosis , bacteria associated with bad skin odor. Finally, this biotransformed oil was used without further treatments (e.g., recovery or purification procedures) to prepare two cosmetic formulations (in a dosage of 1.5 %), aiming for both fragrant and deodorant activity. • Odor-active ethyl esters were formed in lipase-biotransformed licuri oil. • 8.22 g/L ethyl octanoate was formed with 7 % lipase, 51:49 alcohol:oil ratio at 58°C. • Antibacterial activity of biotransformed oil could prevent bad skin odor. • Cosmetic formulations were prepared with 1.5 % biotransformed licuri oil. • No purification procedures were needed to use a natural fragrant mixture. [ABSTRACT FROM AUTHOR]

The enzymatic synthesis of xylose fatty acid esters was carried out in two steps: hydrolysis of degummed soybean oil (DSO) and esterification of the produced and purified free fatty acids (FFA) with xylose. Different lipases immobilized on a hydrophobic support were evaluated in the hydrolysis of DSO and an experimental design was used to optimize the reaction. Eversa® Transform 2.0 (EV-Purolite) yielded 93% conversion after 6 h using biocatalyst load of 6.53 wt%, water/oil mass ratio of 5.5 and temperature of 48.4 °C. High operational stability for EV-Purolite was found using a sequential batch strategy and the possibility of concentrating glycerol. In the esterification stage, lipase from Thermomyces lanuginosus (TLL-Purolite) and lipase B from Candida antarctica showed better performance than lipase from porcine pancreas and EV-Purolite. About 17% of FFAs (0.85 molecules of FAA per xylose molecule) was consumed using an enzyme load of 5 wt% of TLL-Purolite and FFA/xylose molar ratio of 5. Sequential esterification batches showed low operational stability of TTL-Purolite due to the desorption of TLL from the support. The final mixture of the reaction medium containing xylose fatty acid esters showed emulsifying properties similar to those of commercial surfactant. [Display omitted] • Xylose fatty acid esters production by degummed soybean oil hydroesterification. • Hydrolysis catalyzed by immobilized Eversa produced 92% of FFAs after 6 h. • Reuse of immobilized Eversa for five consecutive 3 h-batches of hydrolysis. • Modification of 85% xylose as monoester using immobilized TLL. • Xylose esters showed emulsifying properties similar to commercial surfactants. [ABSTRACT FROM AUTHOR]

The 2-pyrone moiety is present in a wide range of structurally diverse natural products with various biological activities. The plant biosynthetic routes towards these compounds mainly depend on the activity of either type III polyketide synthase-like 2-pyrone synthases or hydroxylating 2-oxoglutarate dependent dioxygenases. In the present study, the substrate specificity of these enzymes is investigated by a systematic screening using both natural and artificial substrates with the aims of efficiently forming (new) products and understanding the underlying catalytic mechanisms. In this framework, we focused on the in vitro functional characterization of a 2-pyrone synthase Gh2PS2 from Gerbera x hybrida and two dioxygenases AtF6'H1 and AtF6'H2 from Arabidopsis thaliana using a set of twenty aromatic and aliphatic CoA esters as substrates. UHPLC-ESI-HRMSn based analyses of reaction intermediates and products revealed a broad substrate specificity of the enzymes, enabling the facile "green" synthesis of this important class of natural products and derivatives in a one-step/one-pot reaction in aqueous environment without the need for halogenated or metal reagents and protective groups. Using protein modeling and substrate docking we identified amino acid residues that seem to be important for the observed product scope. • Enzymatic synthesis led to the one-pot formation of 2-pyrones from coenzyme A esters. • Promiscuous polyketide synthases or hydroxylases were applied in the reactions. • The syntheses yielded both natural and new-to-nature 2-pyrones including coumarins. • The formed derivatives constitute lead structures for improved aromas and biocides. [ABSTRACT FROM AUTHOR]

Delivering functional gene into targeted skin cells or tissues to modulate the genes expression, has the potential to treat various hereditary cutaneous disorders. Nevertheless, the lack of safe and effective gene delivery vehicles greatly limits the clinical translation of gene therapy for inherited skin diseases. Herein, we developed a facile elution fractionation strategy to isolate eight HPAEs with M w ranging from 7.6 to 131.8 kg/mol and Đ < 2.0 from the one crude HPAE 23.7k , and investigated the expression efficiency for TGM1 and COL7A1 plasmids. Gene transfection results revealed that the intermediate MW HPAEs, HPAE 20.6k , exhibited the highest gene transfection efficiency (46.4%) and the strongest mean fluorescence intensity (143,032 RLU), compared to other isolated components and the crude product. Importantly, best-performing isolated HPAE effectively delivered COL7A1 (15,974 bp) and TGM1 (7181 bp) plasmids, promoting the efficient expression of type VII collagen (C7) and transglutaminase-1 proteins in cutaneous cells. Our study establishes a straightforward step-by-step elution fractionation strategy for the development of HPAEs gene delivery vectors, expediting their clinical translation in inherited skin diseases. HPAEs crude polymer is fractionated to eight HPAEs with M w ranging from 7.6 to 131.8 kg/mol and Đ < 2.0. The best-performing isolated HPAE effectively delivered COL7A1 (15,974 bp) and TGM1 (7181 bp) plasmids, promoting the efficient expression of type VII collagen (C7) and transglutaminase-1 proteins in cutaneous cells. [Display omitted] • We establish a straightforward step-by-step elution fractionation strategy to isolate HPAEs with different molecular weight. • Isolated intermediate molecular weight HPAEs exhibit high transfection efficiency and biocompatibility in diverse cell types. • The top-performing HPAEs efficiently deliver TGM and COL7A1 DNA to potentially rescue hereditary cutaneous disorders. [ABSTRACT FROM AUTHOR]

The synthesis of butyl butyrate, medium chain flavored esters by green chemistry is of immense importance to the food industry. In the present work, green synthesis of iron-alginate nanogels is done using a water-in-oil microemulsion method using food-grade oil for immobilization of Candida rugosa lipase (CrL). The morphological characterization of Fe-Alg nanogels was accomplished using dynamic light scattering (DLS) and scanning electron microscopy (SEM). Elongated tube-shaped Fe-Alg showed a hydrodynamic diameter of 100 ± 2 nm and a zeta potential of − 28 ± 4 mV. The nanogels exhibit an immobilization efficiency of 98%. Taguchi design-assisted immobilization of CrL onto Fe-Alg was effective in predicting the maximum response against immobilization parameters (0.7 µgm/ml of substrate, 20 min immobilization, 53⁰ C and pH 8.5). The esterification of butyl butyrate (∼90%) was completed in 6 h, which is confirmed by gas chromatography. The application of food-grade oil in the microemulsion method (water-in-oil) of nanogel synthesis is an attractive improvement for the development of support matrix in enzyme immobilization and ester synthesis. [Display omitted] • Iron-alginate nanogel synthesized using food-grade materials. • Iron-alginate support matrix used for immobilization of Candida rugosa lipase. • Optimization of immobilization parameters by Taguchi method. • Under optimized conditions, the yield of butyl butyrate reached 90%. [ABSTRACT FROM AUTHOR]

Drugs that form self-assembled supramolecular structures to be most-active is a promising way of creating new highly specific and active pharmaceuticals. Controlling the activity of bioactive supramolecular structures such as drug-loaded micelles is possible by both core/shell and inter-assembly cross-linking. However, if the flexibility of the assembly is mandatory for the activity cross-linking is not feasible. Thus, such structures cannot be manipulated in their activity. The present study demonstrates a novel concept to control the activity of not drug-releasing, non-cross-linked bioactive superstructures. This is achieved by formation of nanostructured nanoparticles derived by non-covalent inter-assembly cross-linking of the superstructures. This is shown on the example of amphiphilic diblock-copolymers conjugated with the antibiotic ciprofloxacin (CIP). These polymer-antibiotic conjugates form worm micelles, which greatly activate the conjugated antibiotic without releasing it. Non-covalent inter-assembly cross-linking of these CIP-worm-micelles with amphiphilic triblock copolymers terminated with lipase-cleavable esters leads to nanostructured nanoparticles that resemble cross-linked worm micelles and show an up to 135-fold lower activity than the free worm micelles. The activity of the worm-micelles can be fully recovered by cleaving the end groups of the polymeric cross-linker with lipase. [Display omitted] • nanoprecipitation inactivates ciprofloxacin polymer conjugate (PAC) worm micelles. • non-covalent cross-linking of PAC by triblockcopolymers (TBC) with ester end groups. • lipase cleaves ester end groups of TBC in aggregates. • lipase destroys superstructure of aggregates. • lipase releases activated, antibacterial PAC worm micelles. [ABSTRACT FROM AUTHOR]

• TCEP and TCPP were dominant in the seawater and atmosphere from the northwest Pacific to the Southern Ocean. • Dry and wet deposition were two main processes influenced the air-seawater transport of OPEs in the Ross Sea. • Ross Sea has played the role of a "sink" of OPEs in summer. Eleven organophosphate esters (OPEs) in the air and seawater were investigated from the northwestern Pacific Ocean to the Southern Ocean during the 2018 Chinese 34th Antarctic Scientific Expedition. The concentration of total OPEs ranged from 164.82 to 3501.79 pg/m3 in air and from 4.54 to 70.09 ng/L in seawater. Two halogenated OPEs, tri(chloropropyl) phosphate (TCPP) and tri (2-chloroethyl) phosphate (TCEP), were generally more abundant than the non-halogenated OPEs. A level III fugacity model was developed to simulate the transfer and fate of seven OPEs in the air and seawater regions of the central Ross Sea. The model results indicate that OPEs are transferred from the air to the seawater in the central Ross Sea in summer, during which the Ross Sea acts as a final OPE sink. Dry and wet deposition dominated the processes involving OPE transfer to seawater. The OPE degradation process was also found to be more pervasive in the atmosphere than in the seawater region. These findings highlights the importance of long-range transport of OPEs and their air–seawater interface behavior in the Antarctic. [ABSTRACT FROM AUTHOR]

• A quick metabolism-based in vitro developmental toxicity assay was established. • NEOs and OPEs may interfere with human early embryonic development. • NEOs and OPEs may have milder adverse effects on development after metabolism. In recent years, neonicotinoids (NEOs) and organophosphate esters (OPEs) have been widely used as substitutes for traditional pesticides and brominated flame-retardants, respectively. Previous studies have shown that those compounds can be frequently detected in environmental and human samples, are able to penetrate the placental barrier, and are toxic to animals. Thus, it is reasonable to speculate that NEOs and OPEs may have potential adverse effects in humans, especially during development. We employed a human embryonic stem cell differentiation- and liver S9 fraction metabolism-based fast screening model to assess the potential embryonic toxicity of those two types of chemicals. We show that four NEO and five OPE prototypes targeted mostly ectoderm specification, as neural ectoderm and neural crest genes were down-regulated, and surface ectoderm and placode markers up-regulated. Human liver S9 fraction's treatment could generally reduce the effects of the chemicals, except in a few specific instances, indicating the liver may detoxify NEOs and OPEs. Our findings suggest that NEOs and OPEs interfere with human early embryonic development. [Display omitted] [ABSTRACT FROM AUTHOR]

Gene therapy holds great potential for treating Lung Cystic Fibrosis (CF) which is a fatal hereditary condition arising from mutations in the CF transmembrane conductance regulator (CFTR) gene, resulting in dysfunctional CFTR protein. However, the advancement and clinical application of CF gene therapy systems have been hindered due to the absence of a highly efficient delivery vector. In this work, we introduce a new generation of highly branched poly(β -amino ester) (HPAE) gene delivery vectors for CF treatment. Building upon the classical chemical composition of HPAE, a novel backbone cationization strategy was developed to incorporate additional functional amine groups into HPAE without altering their branching degree. By carefully adjusting the type, proportion, and backbone distribution of the added cationic groups, a series of highly effective HPAE gene delivery vectors were successfully constructed for CF disease gene therapy. In vitro assessment results showed that the backbone cationized HPAEs with randomly distributed 10% proportion of 1-(3-aminopropyl)-4-methylpiperazine (E7) amine groups exhibited superior transfection performance than their counterparts. Furthermore, the top-performed backbone cationized HPAEs, when loaded with therapeutic plasmids, successfully reinstated CFTR protein expression in the CFBE41o- disease model, achieving levels 20–23 times higher than that of normal human bronchial epithelial (HBE) cells. Their therapeutic effectiveness significantly surpassed that of the currently advanced commercial vectors, Xfect and Lipofectamine 3000. [Display omitted] [ABSTRACT FROM AUTHOR]

• The viscosities of POE32 and PVE32 oils saturated with R13I1 were measured. • The experimental viscosity data were correlated using three viscosity models. • The viscosities of R13I1/oil mixture decreased sharply with increasing solubility. Trifluoroiodomethane (R13I1) has attracted extensive attention because of its excellent environmental protection performance, and can be used as a component of environmentally friendly refrigerant blends. To better understand the cycle performance of R13I1 as a refrigerant, it is necessary to study the thermodynamic properties of the R13I1/lubricating oil mixture. In this work, the viscosities of polyol ester (POE) oil (RL 32H) and polyvinylether (PVE) oil (FVC 32D) saturated with R13I1 were measured at temperatures ranging from 293.15 to 353.15 K and pressures up to 0.6 MPa using a custom equilibrium viscosity system. The viscosities of R13I1/RL 32H and R13I1/FVC 32D showed similar trends with temperature, pressure, and solubility. With the increase of the solubility of R13I1 in the oil, the viscosity of the mixture decreased sharply at first and then tended to be flat. The dissolved R13I1 in oil greatly reduced the viscosity of lubricating oil, and the effect of R13I1 on the viscosity of RL 32H was greater than that of FVC 32D. The experimental viscosity data were correlated using the modified Setchenow-type equation, the Eyring-NRTL model, and the Eyring-MTSM model, and the calculated results of the models were in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

This scientific endeavor aims at green synthesis of zinc oxide nanoparticles (ZnONPs) using Clerodendrum infortunatum leaf aqueous extract. After synthesis they were characterized using different analytical techniques like UV–Vis spectroscopy, FTIR spectroscopy, X-ray diffraction analysis and SEM imaging. Furthermore, their antimicrobial activity via agar well diffusion method and minimum inhibitory concentration (MIC) analysis also shows the activity against Escherichia coli (MTCC 40) , Staphylococcus aureus (MTCC 1114), and Klebsiella pneumoniae (MTCC 432). UV–Vis spectroscopy has shown the characteristic peak of ZnO at 356 nm. FTIR analysis revealed the role of phenols, proteins, carboxylic acid and its esters in fabricating ZnONPs. IR spectral peak at 671 cm−1 confirmed the presence of ZnO. The characterization result of SEM support that the synthesized nanoparticles are spherical in shape with 32 nm of size. Best inhibition was shown against E. coli with MIC value of 0.156 mg/ml. Overall, this work demonstrates the ecofriendly and cost-effective synthesis of ZnONPs along with good antibacterial activity compared with previous reports. C. infortunatum extract mediated zinc oxide nanoparticles (CIAQ-ZnONPs) can be utilized effectively for therapeutic and biomedical applications. [Display omitted] • Utilization of ecofriendly materials for zinc oxide nanoparticles synthesis from Clerodendrum infortunatum. • Fabrication of zinc oxide nanoparticles by phenols, proteins and esters of carboxylic acid present in extract. • Characterization of synthesized nanoparticles via UV–Vis, FTIR, XRD, and FE-SEM. • Synthesized nanoparticles demonstrated antibacterial efficacy against gram-positive and gram-negative bacterial pathogens. [ABSTRACT FROM AUTHOR]

Amide-to-ester substitutions are used to study the role of the amide bonds of the protein backbone in protein structure, function, and folding. An amber suppressor tRNA/synthetase pair has been reported for incorporation of p-hydroxy-phenyl-L-lactic acid (HPLA), thereby introducing ester substitution at tyrosine residues. However, the application of this approach was limited due to the low yields of the modified proteins and the high cost of HPLA. Here we report the in vivo generation of HPLA from the significantly cheaper phenyl-L-lactic acid. We also construct an optimized plasmid with the HPLA suppressor tRNA/synthetase pair that provides higher yields of the modified proteins. The combination of the new plasmid and the in-situ generation of HPLA provides a facile and economical approach for introducing tyrosine ester substitutions. We demonstrate the utility of this approach by introducing tyrosine ester substitutions into the K+ channel KcsA and the integral membrane enzyme GlpG. We introduce the tyrosine ester in the selectivity filter of the M96V mutant of the KcsA to probe the role of the second ion binding site in the conformation of the selectivity filter and the process of inactivation. We use tyrosine ester substitutions in GlpG to perturb backbone H-bonds to investigate the contribution of these H-bonds to membrane protein stability. We anticipate that the approach developed in this study will facilitate further investigations using tyrosine ester substitutions. [ABSTRACT FROM AUTHOR]

The rise in fluoroquinolone concentrations in wastewater caused significant concern due to their potential acute toxicity to living organisms. A novel eco-friendly adsorbent, crosslinked potato starch ester, was used to remove ciprofloxacin from a simulated aqueous solution by a batch adsorption process and used its obtained parameters to solve mathematical modeling. With a maximum adsorption capacity of 243.90 mg/g, the ciprofloxacin adsorption on crosslinked potato starch ester was suitable for the Langmuir isotherm model. The kinetics of ciprofloxacin adsorption showed that the pseudo-first-order kinetic model was a good fit for the adsorption process. Thermodynamic parameters exhibited that ciprofloxacin adsorption onto crosslinked potato starch ester was exothermic, achievable, and spontaneous. Finally, the process is simulated under various operating conditions using the mathematical model of a fixed bed continuous adsorption column. According to the results, under optimal operation conditions of inlet fluid velocity, particle size, bed height, and initial ciprofloxacin concentration with values 0.002 m/s, 1.2 mm, 0.2 m, and 143.4 mg/L, respectively, the highest dynamic adsorption capacity was 18.75 mg/g. [Display omitted] • Crosslinked potato starch ester, a eco-friendly adsorbent, was synthesized for removing ciprofloxacin from simulated wastewater. • Mathematical for the fixed bed continuous adsorption column was developed to simulate the process • Optimum operation conditions and fundamental design factors resulted in maximum dynamic adsorption capacity. [ABSTRACT FROM AUTHOR]

Diesel engines fueled by liquid fuels will continue to dominate the transportation and heavy machinery application market despite the advancement of other technologies. Studies have yet to be conducted to investigate the combined influence of carbon chain length, oxyfuel type, oxygen content, and blending ratio of esters and alcohols as additives in diesel fuel. The present study addresses this by preparing two sets of experiments using three-carbon (C 3) and four-carbon (C 4) additives, one at an equal blending ratio of 4% and the other at an equal oxygen mass content of 1.94%. Although the additives caused up to 24.84% rise in brake specific fuel consumption at low load, the value diminished to 7.86% at medium load and 11.63% at high load. The C 4 fuels were found to have better NOx reduction potential than the C 3 fuels. However, most additives significantly increased CO emissions, except for EE4.9 (4.9% ethyl ethanoate and 95.1% diesel), leading to 3.7% and 7.1% lower CO emissions than neat diesel at low and medium loads, respectively. Smoke emissions were also reduced by up to 32.84% when oxygenated additives were used. Although all blends tested are promising fuel alternatives in a diesel engine, EE4.9 provided the most suitable trade-off between engine performance and emissions. [Display omitted] [ABSTRACT FROM AUTHOR]

Sec-butyl alcohol (SBA), a common chemical intermediate, is used as an anti-emulsion, dye dispersant, industrial detergent, and raw material to produce methyl ethyl ketone. To further reduce the energy consumption and production cost of the hydrolysis of sec-butyl acetate (SBAC) to SBA, a reactive distillation coupled with extractive distillation using a mixed entrainers process was proposed in this study. Based on the relative volatility curve and quantum chemical calculations, EG and DMSO were selected as potential entrainers. Based on the total annual production cost, the appropriate ratio of mixed solvent is obtained (EG: DMSO = 9:1). The thermal coupling distillation technology is introduced into the proposed process to achieve energy-saving further. The results showed that the thermodynamic efficiency of the thermal coupling process using mixed entrainers increased by 18.02%, the total annual cost is saved by 15.18%, and CO 2 emissions were reduced by 391.82 kg/h compared to the process using single DMSO entrainers process. [Display omitted] • Quantum chemical calculation and VLE data were used to screen mixed extractants. • Combination of mixed extractant and thermal coupling process can effectively save energy. • The thermodynamic efficiency of the novel process can be improved by 18.02%. [ABSTRACT FROM AUTHOR]

[Display omitted] The establishment of latent cellular and anatomical viral reservoirs is a major obstacle to achieving a cure for people infected by HIV. Mesenteric lymph nodes (MLNs) are one of the most important anatomical reservoirs of HIV. Suboptimal levels of antiretroviral (ARVs) drugs in these difficult-to-penetrate viral reservoirs is one of the limitations of current antiretroviral therapy (ART) regimens. This study aimed to design and assess highly lipophilic ester prodrugs of dolutegravir (DTG) formulated with long-chain triglyceride (LCT) for delivery of DTG to the viral reservoir in mesenteric lymph and MLNs. A number of alkyl ester prodrugs of DTG were designed based on the predicted affinity to chylomicrons (CM), and the six most promising prodrugs were selected and synthesised. The synthesised prodrugs were further assessed for their intestinal lymphatic transport potential and biotransformation in biorelevant media in vitro and ex vivo. DTG and the most promising prodrug (prodrug 5) were then assessed in pharmacokinetic and biodistribution studies in rats. Although oral administration of 5 mg/kg of unmodified DTG (an allometrically scaled dose from humans) with or without lipids achieved concentrations above protein binding-adjusted IC 90 (PA-IC 90) (64 ng/mL) in most tissues, the drug was not selectively targeted to MLNs. The combination of lipophilic ester prodrug and LCT-based formulation approach improved the targeting selectivity of DTG to MLNs 4.8-fold compared to unmodified DTG. However, systemic exposure to DTG was limited, most likely due to poor intestinal absorption of the prodrug following oral administration. In vitro lipolysis showed a good correlation between micellar solubilisation of the prodrug and systemic exposure to DTG in rats in vivo. Thus, it is prudent to include in vitro lipolysis in the early assessment of orally administered drugs and prodrugs in lipidic formulations, even when intestinal lymphatic transport is involved in the absorption pathway. Further studies are needed to clarify the underlying mechanisms of low systemic bioavailability of DTG following oral administration of the prodrug and potential ways to overcome this limitation. [ABSTRACT FROM AUTHOR]

Acetate esters, such as isoamyl acetate and ethyl acetate, are major aroma components of alcoholic beverages. They are produced through synthesis from acetyl CoA and the corresponding alcohol by alcohol acetyltransferase (AATase) with specific control of reaction factors, including unsaturated fatty acids and precursors, the percentage of nitrogen, and oxygen. However, the mechanisms by which these specific reaction factors affect acetate ester production remain largely unknown. The cellular mechanisms underlying the effects of these factors on acetate ester production were examined by purifying AATase from yeast, characterizing it, and cloning the ATF gene encoding AATase from sake yeast and bottom-fermenting yeast. Genetic and biochemical studies suggested that the decrease in acetate production with the addition of oxygen and unsaturated fatty acids was due to a decrease in enzyme synthesis resulting from transcriptional repression of the ATF1 gene, which is responsible for most of the AATase activity. Furthermore, these results suggest that expression of the ATF1 gene is intricately regulated by a number of transcriptional regulatory genes such as ROX1 and RAP1. Based on these results, the mechanism of ester regulation by oxygen, unsaturated fatty acids and precursors, and ratio of nitrogen source are becoming clearer from a molecular biological point of view. The physiological significance of ester production by yeast is then discussed. In this review, we summarize the studies on AATase, ATF gene, regulation of ester production, and physiological significance of acetate ester. [Display omitted] [ABSTRACT FROM AUTHOR]

The use of beneficial organisms for the biocontrol of soil-borne pathogens in forestry is still poor explored. In this work, the nutritional demands of 10 previously selected isolates of Trichoderma for the biocontrol of forest soil-borne pathogens have been tested by Phenotype Microarray technology, to investigate about their C-source utilization and exploring the possibility to obtain a microbial consortia (SynCom), an innovative strategy for the biocontrol of plant disease. All Trichoderma isolates tested in this study showed a high spore germination percentage within 3 d and evidenced nutritional preference regardless of the species they belong to, and unrelated to their soil of origin. Results of growth curve analysis and MANOVA test revealed that all isolates assimilate a broad range of substrates, generally preferring complex compounds such as monosaccharides related compounds, nitrogen compounds, carboxylic acids and esters. No evidence of competition for nutritional resources have been observed among isolates of this study. As a result, a combination of different isolates could be proposed to obtain a SynCom useful for the practice of phytopathogen biocontrol in forestry. The addition of i-erythritol, adenosine and turanose to a growth substrate could be suggested as stimulating compounds for the growth of the selected Trichoderma isolates. • Nutrient assimilation of microbial strains can be examined by phenotype microarray. • The tested Trichoderma isolates don't compete for any of the tested C-sources. • Turanose, i-erythritol and adenosine stimulate the growth of Trichoderma hamatum and Trichoderma koningiopsis tested isolates. [ABSTRACT FROM AUTHOR]

[Display omitted] The mechanism of the esterification reaction without the use of acid as a catalyst was examined using the AIMD method. A dissociative mechanism for the interaction of acid and alcohol without the formation of a transition state has been proposed. [ABSTRACT FROM AUTHOR]

The increasing glycerol consumption will result in an issue for further applications of methyl esters, which are produced together with glycerol by transesterification of vegetable oils/animal fats on industrial scale. One possibility is the formation of bio-epoxides, which can be used for bio-lubricants, precursors for chemicals or CO 2 capture, and so they can replace products from crude oil. Therefore, the mathematical models describing epoxidation of methyl esters, i.e., the influence of reaction conditions (time, temperature, etc.) on the properties of epoxides (iodine and epoxide values, relative conversion to oxirane, etc.) were created/calculated to decrease the production cost. It was found that (i) higher initial iodine value of esters, (ii) higher reaction temperature, (iii) higher concentration of formic acid and (iv) longer reaction time caused more formed epoxides. In contrast, a higher concentration of hydrogen peroxide caused epoxide ring opening and the formation of side products. The catalyst (H 2 SO 4) and the intensity of stirring were statistically insignificant. The drying of epoxides was carried out by distillation and improved by the addition of a small amount of methanol. The models allow the synthesis of epoxides with desired properties, which are biodegradable and nontoxic with variety of applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Daqu , a fermentation starter, was important source of key flavors of Chinese Baijiu. The quality of Chinese Baijiu could be significantly affected by the ester-synthesis microorganisms. In order to clarify the microbial community that promoted the ester formation in Daqu , the dynamic changes of microbial community and non-volatile profiles of Qing-flavor Daqu and Nong-flavor Daqu samples through the whole making process were investigated by Illumina MiSeq platform and liquid chromatograph-mass spectrometry (LC-MS). The non-volatile compounds related to ester synthesis were identified by comparing with ester synthesis pathway and partial least squares discriminant analysis (PLS-DA). Correlations between microbial community and non-volatile metabolites involved in ester synthesis of two types of Daqu were disclosed by Pearson correlation analysis. Results showed that a total of 50 key compounds involved in ester synthesis were identified and 25 primary functional microorganisms were screened in 39 samples. Among them, in Qing-flavor Daqu , the top three primary functional microorganisms that had strong correlations with ester-formation precursors were Lactobacillus , Pantoea , and Sphingomonas ; Lactobacillus and Pantoea had significantly positive interactions with various microorganisms, but Sphingomonas did not interact with others. In Nong-flavor Daqu , the top three primary functional microorganisms that had strong correlations with ester-formation precursors were Candida , Apiotrichum , and Cutaneotrichosporon. Candida showed strong positive correlation with other microorganisms, whereas Apiotrichum and Cutaneotrichosporon had no interaction with other microorganisms. The study could help our understanding of the microbial metabolism process in Daqu and provided a scientific basis for a controllable and feasible fermentation system. [ABSTRACT FROM AUTHOR]

Native starch has many functional disadvantages that limit its wide commercial application as a renewable biopolymer. Therefore, starch modification is needed. Esterification/compounding/polymerization modification of starch using microwave combined with acid (anhydride) (MCA) to introduce new groups and give new functional properties to the starch. In the process, the structural and physicochemical properties of the starch are changed. The study of changes in the structure and physicochemical properties of starch by MCA is particularly significant to guide the application of modified starches and to modify them more effectively. This review describes the changes in the structure and physicochemical properties of starch ester/copolymer/complex synthesized by MCA and the applications for which the relevant modified starches were obtained. Future directions for MCA modification are also discussed. The structure and physicochemical properties of the starch obtained after modification of the starch by MCA are mainly related to the degree of substitution (DS) of the modified starch and the type of acid (anhydride). The physicochemical properties and structural changes of the starch appear differently depending on the modification method. Most starch modifications show the same trends in the structural and physicochemical properties of the starch. The DS of the modified starch obtained after modification of the starch by MCA is low, so other techniques can be combined to increase the DS of the modified starch and obtain a suitable modified starch. • Excessive microwave power/time will reduce the DS of modified starch. • The modification of starch by MCA can endow starch with new functional properties. • MCA modification can improve the DS of starch and shorten the reaction time. • The properties of the modified starch are related to the acids (anhydrides) used. [ABSTRACT FROM AUTHOR]

[Display omitted] • The permeability of drug and their modifications was investigated in the presence of a rotating magnetic field. • The rotating magnetic field may increase the permeability of ibuprofen. • Structural modifications of ibuprofen increase the permeability of the active substance. • In the presence of a magnetic field, the isopropyl ester ibuprofenates penetrate at a similar level as ibuprofen compared to the non-field control. A method of increasing the permeability of ibuprofen through the skin using a rotating magnetic field (RMF) is presented. This study evaluated whether 50 Hz RMF modifies ibuprofen's permeability through the skin. Ibuprofen and its structural modifications in the form of ibuprofenates of isopropyl esters of L-amino acids such as L-valine, L-phenylalanine, L-proline, and L-aspartic acid were used in the research. To this end, Franz cells with skin as membrane were exposed to 50 Hz RMF with 5% ibuprofen and its derivatives in an ethanol solution for 48 h. Following the exposures, the amount of penetrated compound was analysed. Regardless of the compound tested, a significant increase in drug transport through the skin was observed. The differences in the first 30 min of permeation are particularly noticeable. Furthermore, it was shown that using RMF increases the permeability of ibuprofen from 4 to 244 times compared to the test without the RMF. The greatest differences were observed for unmodified ibuprofen. However, it is noteworthy that the largest amounts of the active substance were obtained with selected modifications and exposure to RMF. The RMF may be an innovative and interesting technology that increases the penetration of anti-inflammatory and anti-ache drugs through the skin. [ABSTRACT FROM AUTHOR]

Biotin is an essential coenzyme that is bound to carboxylases and participates in fatty acid synthesis. The fact that sake yeast exhibit biotin prototrophy while almost all other Saccharomyces cerevisiae strains exhibit biotin auxotrophy, implies that biotin prototrophy is an important factor in sake brewing. In this study, we inserted a stop codon into the biotin biosynthetic BIO3 gene (cording for 7,8-diamino-pelargonic acid aminotransferase) of a haploid sake yeast strain using the marker-removable plasmid pAUR135 and investigated the fermentation profile of the resulting bio3 mutant. Ethanol production was not altered when the bio3 mutant was cultured in Yeast Malt (YM) medium containing 10% glucose at 15 °C and 30 °C. Interestingly, ethanol production was also not changed during the sake brewing process. On the other hand, the levels of organic acids in the bio3 mutant were altered after culturing in YM medium and during sake brewing. In addition, ethyl hexanoate and isoamyl acetate levels decreased in the bio3 mutant during sake brewing. Metabolome analysis revealed that the decreased levels of fatty acids in the bio3 mutant were attributed to the decreased levels of ethyl hexanoate. Further, the transcription level of genes related to the synthesis of ethyl hexanoate and isoamyl acetate were significantly reduced. The findings indicated that although the decrease in biotin biosynthesis did not affect ethanol production, it did affect the synthesis of components such as organic acids and aromatic compounds. Biotin biosynthesis ability is thus a key factor in sake brewing. [ABSTRACT FROM AUTHOR]

Herein, the evaluation of waste fish (WF) oils as feedstock for the production of wax esters through transesterification reactions was reported. In particular, the synthesis of an emollient ester in the presence of oleyl alcohol and using an immobilized lipase catalyst was proposed. Lipase from Candida rugosa (CRL) was immobilized (0.5 enzyme/support wt. ratio) on a magnetic amino-functionalized hypercross-linked resin (M-HCLR-NH 2) by ion exchange, interfacial activation, and covalent anchoring, mediated by 1-ethyl-3-(3-dimethyl-aminopropyl)carbodiimide (EDC). The experimental results demonstrated the successful immobilization of lipase on the as-produced M-HCLR-NH 2 with a high immobilization yield of 90%. The immobilized CRL showed very high activity and an activity recovery of ∼ 94%. The immobilized enzyme on the magnetic resin results in more stability and less sensitivity to temperature change than the free counterpart. In addition, during emollient ester synthesis in a solvent system, the immobilized enzyme exhibited very high activity, stability, and excellent reusability, with a yield of 94% after 12 h at 45 °C at an oil:alcohol molar ratio of 1:4 and an immobilized enzyme concentration of 15 wt%./wt of oil. Esters synthesized showed excellent physicochemical properties. [Display omitted] • Candida rugosa lipase was immobilised on an amino-hypercrosslinked resin. • Wax esters by immobilized lipase through waste fish oil transesterification. • Bio-catalyst reusability, high activity and stability, i.e. yield of 94% after 12 h. [ABSTRACT FROM AUTHOR]

Development of prodrugs is a useful strategy to overcome some disadvantages of candidate drugs. Recently, we established a systematic approach to selecting appropriate prodrugs, and validated the utility of this approach using oseltamivir analogues. In this study, the utility of the approach was further examined using candesartan cilexetil and 20 kinds of its analogues having various types of side chain as model compounds. Log D values of analogues (2.5 to 4.7) were higher than that of candesartan (1.0), their active metabolite, and the results were reasonable for the purpose of improving permeability of candesartan. The analogues tended to be more soluble in artificial intestinal fluids than in artificial gastric fluid, owing to their acidic physicochemical characteristics. Their membrane permeabilities were not correlated with log D values, which can be attributed to the metabolism in Caco-2 cells used in this system. In human hepatocytes and enterocytes, 11 out of the 20 analogues were immediately hydrolyzed to candesartan, and species differences were observed in the hydrolysis efficiency. This study confirmed the utility of the systematic approach for selection of appropriate prodrugs that could be proceeded to in vivo pharmacokinetics study, with selection of suitable experimental animals. [ABSTRACT FROM AUTHOR]

Biodiesel is a family of renewable engine fuels with carbon-neutral nature. In this work, three C 5 H 10 O 2 esters (methyl butanoate, methyl isobutanoate and ethyl propanoate), which can serve as model compounds of biodiesel and represent linear and branched methyl esters and linear ethyl esters, were investigated to characterize their laminar flame propagation characteristics up to 10 atm and unravel the effects of isomeric fuel structures. A high-pressure constant-volume cylindrical combustion vessel was used to achieve laminar burning velocity measurements at 1–10 atm, 423 K and equivalence ratios of 0.7–1.5, while comparative experimental work was performed on a heat flux burner at 1 atm, 393 K and equivalence ratios of 0.7–1.6 for methyl butanoate and ethyl propanoate. The laminar burning velocity generally decreases with increasing pressure and increases in the order of methyl isobutanoate, methyl butanoate and ethyl propanoate, which shows distinct fuel isomeric effects. A kinetic model of C 5 H 10 O 2 esters was developed and validated against the new data in this work and previous data in literature. Modeling analyses were performed to provide insight into the fuel-specific flame chemistry of the three esters isomers. Remarkable differences in radical pools of three ester isomers are concluded to be responsible for the observed fuel isomeric effects on laminar flame propagation. The feature of two ethyl groups connected to the ester group in ethyl propanoate facilitates the ethyl production and inhibits the methyl and allyl production, making it propagate fastest among the three isomers. The branched structure feature of methyl isobutanoate with methyl and i -propyl groups connected to the ester group prevents the ethyl formation and results in considerable CH 3 and allyl production, which decelerates its laminar flame propagation. [ABSTRACT FROM AUTHOR]

Natural ester is regarded as a potential alternative to mineral insulating oil and has a wide range of applications in power system, but its electrical properties and thermal conductivity still need to be improved. Nano modification technology can improve the performance of natural ester to ensure the stability and reliability of natural ester in power equipment. In this study, nano modified natural ester is prepared with APTES surface modified h-BN, and the mechanism of enhancing the properties of natural ester is explored from the microscopic perspective by molecular simulation. The experimental results showed that nano h-BN had good dispersion stability in natural ester after surface modification with APTES. The electrical properties and thermal conductivity of the nano modified natural ester have been greatly improved, and the relative optimal doping concentration of nanoparticles is 0.03 g/L. The simulation results show that the interfacial thickness between nanoparticles and natural ester is larger and more tightly bound after surface modification, which is beneficial to reduce thermal resistance and improve thermal conductivity of natural ester insulating oil. The traps at the interface between nanoparticles and natural ester can capture free electrons in the oil, thus improving the breakdown voltage of natural ester insulating oil. [ABSTRACT FROM AUTHOR]

Biotransformation of carotol (1), the major sesquiterpenoid of carrot fruit essential oil, by Rhizopus oryzae yielded two new lactate derivatives: 9α-hydroxydaucol-9-lactate (2) and 9α-hydroxydaucol-3,9-dilactate (3). The structures of 1 - 3 were characterized by 1 & 2D NMR spectroscopy in conjunction with HR-ESIMS. Cholinergic deficiency and neuroinflammation are key detrimental processes involved in the etiology of Alzheimer's disease (AD). This study demonstrated that compounds 1 - 3 in addition to the essential oil showed considerable in-vitro inhibition of cyclooxygenase-2 (COX-2), 5-lipoxygenase (5-LOX), and butyrylcholinesterase (BChE). Metabolite 2 showed improved inhibitory activities (9.03, 0.56, and 0.64 μM) against COX-2, 5-LOX, and BChE enzymes, compared to the parent compound, carotol 1 (82.57, 2.11, and 0.74 μM, respectively). The results were correlated to the in-silico binding interactions with the proteins of these enzymes by molecular docking. Carrot essential oil and carotol derivatives are suggested by this study as a potential treatment for neurodegenerative disease associated with neuroinflammation. [Display omitted] • This study described the biotransformation of carotol. • Biotransformation of carotol by Rhizopus oryzae yielded 2 new lactate metabolites. • The metabolites showed improved COX-2, 5-LOX, and BChE enzymes inhibitory activity. • The results were correlated to the in-silico binding interactions. • Carotol derivatives are suggested as a potential treatment for neuroinflammation [ABSTRACT FROM AUTHOR]

Poly(beta-amino esters, PBAEs) are a promising class of cationic polymers synthesized from diacrylates and amines via Michael addition. Recently, PBAEs have been widely developed for drug delivery, immunotherapy, gene therapy, antibacterial, tissue engineering and other applications due to their convenient synthesis, good bio-compatibility and degradation properties. Herein, we mainly summarize the recent progress in the PBAEs synthesis and their applications. The amine groups of PBAEs could be protonated in low pH environment, exhibiting proton sponge and pH-sensitive abilities. Furthermore, the positive PBAEs can interact with negative genes via electrostatic interactions for efficient delivery of nucleic acids. Moreover, positive PBAEs could also directly kill bacteria by disrupting their membranes at high doses. Finally, PBAEs can augment the immune responses, and improve the bioactivity of hydrogels in tissue engineering. [Display omitted] [ABSTRACT FROM AUTHOR]

Single-pulse shock-tube experiments were used to study the thermal decomposition of selected oxygenated hydrocarbons: Ethyl propanoate (C 2 H 5 OC(O)C 2 H 5 ; EP), propyl propanoate (C 3 H 7 OC(O)C 2 H 5 ; PP), isopropyl acetate ((CH 3) 2 HCOC(O)CH 3 ; IPA), and methyl isopropyl carbonate ((CH 3) 2 HCOC(O)OCH 3 ; MIC) The consumption of reactants and the formation of stable products such as C 2 H 4 and C 3 H 6 were measured with gas chromatography/mass spectrometry (GC/MS). Depending on the considered reactant, the temperatures range from 716–1102 K at pressures between 1.5 and 2.0 bar. Rate-coefficient data were obtained from first-order analysis. All reactants primarily decompose by six-center eliminations: EP → C 2 H 4 + C 2 H 5 COOH (propionic acid); PP → C 3 H 6 + C 2 H 5 COOH; IPA → C 3 H 6 + CH 3 COOH (acetic acid); MIC → C 3 H 6 + CH 3 OC(O)OH (methoxy formic acid). Experimental rate-coefficient data can be well represented by the following Arrhenius expressions: k (EP → products) = 1013.49±0.16 exp(−214.95±3.25 kJ/mol/ RT) s−1; k (PP → products) = 1012.21±0.16 exp(–191.21±2.79 kJ/mol/ RT) s−1; k (IPA → products) = 1013.10±0.31 exp(–186.38±5.10 kJ/mol/ RT) s−1; k (MIC → products) = 1012.43±0.29 exp(–165.25±4.46 kJ/mol/ RT) s−1. The determination of rate coefficients was based on the amount of C 2 H 4 or C 3 H 6 formed. The potential energy surface (PES) of the thermal decomposition of these four reactants was determined with the G4 composite method. A master-equation analysis was conducted based on energies and molecular properties from the G4 computations. The results indicate that the length of a linear alkyl substituent does not significantly influence the rate of six-center eliminations, whereas the change from a linear to a branched alkyl substituent results in a significant reactivity increase. The comparison between rate-coefficient data also shows that alkyl carbonates have higher reactivity towards decomposition by six-center elimination than esters. The results are discussed in in the context of reactivity patterns of carbonyl compounds. [ABSTRACT FROM AUTHOR]

[Display omitted] Ethyl 3-alkoxy-2-cyanopropanoates were prepared by the reaction of ethyl 2-cyanoacrylate with the corresponding linear alkanols C 6 –C 12 in acidic medium. Their treatment with water as a weak nucleophile resulted in elimination of the alkanol and the formation of oligocyanoacrylate terminated with the alkoxy group. The oligomers were studied by NMR spectroscopy, IR spectroscopy, MALDI-TOF mass-spectrometry and dynamic light scattering. [ABSTRACT FROM AUTHOR]

Catalytic dehydrogenation of ethanol produces acetaldehyde, an important precursor for several value-added chemicals such as acetic acid and acetate esters. In this paper, we demonstrate that Zn-containing MFI zeolites are highly active and selective catalysts for this process. Furthermore, we show that their activity and selectivity depend on the chemical composition and preparation of the catalysts. The best catalyst comprises 5 wt% Zn on Silicalite-1 zeolite and results in 65.2% conversion and 94.5% selectivity towards acetaldehyde at 400 ℃. We relate the high selectivity to the absence of Brønsted acidic silanol groups, which suppresses the dehydration of ethanol into ethylene. Furthermore, while pure HZSM-5 and NaZSM-5 zeolites result in dehydration products, such as ethylene and diethyl ether, Zn on NaZSM-5 zeolite also results in acetaldehyde, which confirms that Zn is the active site. Finally, we compare different preparation procedures to show that several Zn-species may be active for the catalytic reaction. [Display omitted] • Ethanol conversion to acetaldehyde was investigated over Zn-containing MFI zeolite. • Zn/Silicalite-1 exhibited high activity with the acetaldehyde selectivity of 94.5%. • Zn/HZSM-5 facilitated the ethylene production due to the strong Brønsted acidity. • Zn played a critical role of acetaldehyde production when NaZSM-5 was used as the support. [ABSTRACT FROM AUTHOR]

The poor water solubility and stability of lutein limit its application in industry. Microencapsulation technology is an excellent strategy to solve these problems. This study used citric acid esterified potato starch and whey protein as an emulsifier to prepare oil-in-water lutein emulsion, and microcapsules were constructed by spray drying technology. The effects of different component proportions on microcapsules' microstructure, physical and chemical properties, and storage stability were analyzed. Citrate esterified potato starch had good emulsifying properties, and when compounded with whey protein, the encapsulation efficiency (EE) of microcapsules increased, and the embedding effect of lutein improved. After microencapsulation, the solubility of lutein increased significantly, reaching over 49.71 %, and gradually raised with more whey protein content. Furthermore, the high proportion of whey protein helped improve microcapsules' EE and thermal properties, with the maximum EE reaching 89.36 %. The glass transition temperatures of microcapsules were all higher than room temperature, which indicated that they keep a stable state under general storage conditions. The experimental results of this study may provide a reference for applying lutein in food and other fields. • Citrate esterified starch and whey protein had good embedding effect on lutein. • The compound of starch and protein avoided the defects of single wall material. • Various proportions of wall materials had great influence on lutein microcapsules. • The encapsulation efficiency and solubility of lutein microcapsules were improved. [ABSTRACT FROM AUTHOR]

Translation terminates by releasing the polypeptide chain in one of two chemical reactions catalyzed by the ribosome. Release is also a target for engineering, as readthrough of a stop codon enables incorporation of unnatural amino acids and treatment of genetic diseases. Hydrolysis of the ester bond of peptidyl-tRNA requires conformational changes of both a class I release factor (RF) protein and the peptidyl transferase center of a large subunit rRNA. The rate-limiting step was proposed to be hydrolysis at physiological pH and an RF conformational change at higher pH, but evidence was indirect. Here, we tested this by activating the ester electrophile at the Escherichia coli ribosomal P site using a trifluorine-substituted amino acid. Quench-flow kinetics revealed that RF1-catalyzed release could be accelerated, but only at pH 6.2-7.7 and not higher pH. This provided direct evidence for rate-limiting hydrolysis at physiological or lower pH and a different rate limitation at higher pH. Additionally, we optimized RF-free release catalyzed by unacylated tRNA or the CCA trinucleotide (in 30% acetone). We determined that these two model release reactions, although very slow, were surprisingly accelerated by the trifluorine analog but to a different extent from each other and from RF-catalyzed release. Hence, hydrolysis was rate limiting in all three reactions. Furthermore, in 20% ethanol, we found that there was significant competition between fMet-ethyl ester formation and release in all three release reactions. We thus favor proposed mechanisms for translation termination that do not require a fully-negatively-charged OH- nucleophile. [ABSTRACT FROM AUTHOR]

Protein therapy targeting the intracellular machinery holds great potentials for disease treatment, and therefore, effective cytosolic protein delivery technologies are highly demanded. Herein, we developed reactive oxygen species (ROS)-degradable, branched poly(β-amino ester) (PBAE) with built-in phenylboronic acid (PBA) in the backbone and terminal-pendent arginine for the efficient cytosolic protein delivery. The PBAE could form stable and cell-ingestible nanocomplexes (NCs) with proteins via electrostatic interaction, nitrogen-boronate (N-B) coordination, and hydrogen bonding, while it can be degraded into small segments by the over-produced H 2 O 2 in tumor cells to enable cytoplasmic protein release. As thus, PBAE exhibited high efficiency in delivering varieties of proteins with distinct molecular weights (12.4–430 kDa) and isoelectric points (4.7-10.5) into tumor cells, including enzymes, toxins, and antibodies. Moreover, PBAE mediated efficient delivery of saporin into tumor cells in vivo , provoking pronounced anti-tumor outcomes. This study provides a robust and versatile platform for cytosolic protein delivery, and the elaborately tailored PBAE may find promising applications for protein-based biological research and disease management. Cytosolic delivery of native proteins holds great therapeutic potentials, which however, is limited by the lack of robust delivery carriers that can simultaneously feature strong protein encapsulation yet effective intracellular protein release. Herein, ROS-degradable, branched poly(β-amino ester) (PBAE) with backbone-embedded phenylboronic acid (PBA) and terminal-pendent arginine was developed to synchronize these two processes. PBA and arginine moieties allowed PBAE to encapsulate proteins via N-B coordination, electrostatic interaction, hydrogen bonding, and salt bridging, while PBA could be oxidized by over-produced H 2 O 2 inside cancer cells to trigger PBAE degradation and intracellular protein release. As thus, the top-performing PBAE mediated efficient cytosolic delivery of various proteins including enzymes, toxins, and antibodies. This study provides a powerful platform for cytosolic protein delivery, and may find promising utilities toward intracellular protein therapy against cancer and other diseases such as inflammation. [Display omitted] [ABSTRACT FROM AUTHOR]

Sorghum peptides can encapsulate caffeic acid phenethyl ester (CAPE) by self-assembly. The water solubility, stability and gastrointestinal release of encapsulated CAPE was significantly improved. [Display omitted] • Sorghum peptides can self-assemble into nanoparticles (SPNs) with a size of 160 nm. • SPNs can encapsulate caffeic acid phenethyl ester (CAPE) through hydrophobic force. • Solubility of encapsulated CAPE was 9.44 times higher than that of free CAPE. • SPNs significantly improved storage stability of CAPE in aqueous solution. • SPNs encapsulation can delay release of CAPE in the gastrointestinal environment. Caffeic acid phenethyl ester (CAPE) is a naturally occurring phenolic compound with various biological activities. However, poor water solubility and storage stability limit its application. In this context, sorghum peptides were used to encapsulate CAPE. Sorghum peptides could self-assemble into regularly spherical nanoparticles (SPNs) by hydrophobic interaction and hydrogen bonds. Solubility of encapsulated CAPE was greatly increased, with 9.44 times higher than unencapsulated CAPE in water. Moreover, the storage stability of CAPE in aqueous solution was significantly improved by SPNs encapsulation. In vitro release study indicated that SPNs were able to delay CAPE release during the process of gastrointestinal digestion. Besides, fluorescence quenching analysis showed that a static quenching existed between SPNs and CAPE. The interaction between CAPE and SPNs occurred spontaneously, mainly driven by hydrophobic interactions. The above results suggested that SPNs encapsulation was an effective approach to improve the water solubility and storage stability of CAPE. [ABSTRACT FROM AUTHOR]

• Synthesis and characterization of new C-26 monensin succinate ester hydrate (2-H 2 O) and its sodium salt (2-Na). • Structures of 2 and 2-Na have been studied by X-ray diffraction. • Dimers with dual linear O − H ⋅⋅⋅O hydrogen bonds are present in the crystals of 2-H 2 O and 2-Na. Monensin succinate ester hydrate (2-H 2 O) has been synthesized by the succinylation of C-26 hydroxyl group of monensin (1) using a simple reaction with succinic anhydride. Additionally, the sodium salt (2-Na) of monensin succinate ester has been obtained. Molecular structures of both compounds (2-H 2 O and 2-Na) were studied using X-ray diffraction of single crystals and spectroscopic methods. According the crystallographic studies of 2-H 2 O and 2-Na , the molecules are held together as dimers linked by the centrosymmetric pairs of intermolecular hydrogen bonds between the carboxylic groups. The crystal structures of compounds 2-H 2 O and 2-Na are compared to those of the known monensin acid hydrate (1-H 2 O) and 1:1 inclusion complex of monensin A sodium salt with acetonitrile (1-Na-CH 3 CN) and that of newly obtained monensin sodium salt monohydrate (1-Na-H 2 O). Comparison of these structures showed a significant impact of C-26 succinate ester moiety on the coordination of the Na+ cation and hydrogen bond. [Display omitted] [ABSTRACT FROM AUTHOR]

This study investigated the effects of cross-linking on the characteristics and in-vitro digestibility of starch-sucrose ester (SE) complexes. To achieve this, corn starch (CS) was cross-linked with various concentrations of sodium trimetaphosphate /sodium tripolyphosphate (5 %, 10 %, and 15 %). Subsequently, cross-linked starches (CLS) were complexed with SE through hydrothermal treatment. X-ray diffraction analysis revealed that V-type amylose-lipid complexes formed by the interaction between CS and SE. The resultant CS-SE complex significantly reduced CS digestibility, increasing its resistant starch (RS) content from 10.19 % to 22.71 %. The cross-linking modification did not alter the crystalline pattern of the CS-SE complex. Several CLS-SE complexes demonstrated higher enzymatic resistance compared to the CS-SE complex. The CLS10-SE complex exhibited the highest RS content of 39.37 % when the cross-linking agent concentration was 10 %. This phenomenon may be attributable to the cross-linking reaction having enhanced the interaction between starch molecular chains, reducing the solubility and swelling power, thereby hindering the accessibility of starch chains to digestive enzymes. These findings indicate that cross-linking modification is a practical approach to improving the anti-digestion performance of starch-lipid complexes. [Display omitted] • The formation of the V-type CS-SE complex significantly reduced CS digestibility. • Cross-linking significantly inhibited starch leaching and swelling. • CLS-SE complexes were more enzyme resistant than the CS-SE complex. • CLS complexation with SE increased the RS content of CS by 20–30 %. [ABSTRACT FROM AUTHOR]

[Display omitted] • Analogues of the fungal metabolite, eupenifeldin, were generated via semisynthesis. • 29 analogues were generated via 22 separate reactions, including esters, carbonates, sulfonates, and carbamates. • Ten analogues maintained nanomolar potency in cytotoxicity assays. • The succinate analogue increased aqueous solubility over 50 times relative to eupenifeldin. Eupenifeldin (1) is a fungal secondary metabolite possessing bis -tropolone moieties that demonstrates nanomolar cytotoxic activity against a number of cancer cell types. As a potential anticancer lead, this meroterpenoid was used to access 29 semisynthetic analogues via functionalization of the reactive hydroxy groups of the bis -tropolones. A series of ester (2 – 6), carbonate (7 – 8), sulfonate (9 – 16), carbamate (17 – 20), and ether (21 – 30) analogues of 1 were generated via 22 reactions. Most of these compounds were disubstituted, produced via functionalization of both of the tropolonic hydroxy moieties, although three mono-functionalized analogues (6 , 8 , and 24) and one tri-functionalized analogue (3) were also obtained. The cytotoxic activities of 1 – 30 were evaluated against human melanoma and ovarian cancer cell lines (i.e., MDA-MB-435 and OVCAR3, respectively). Ester and carbonate analogues of 1 (i.e., 2 – 8) maintained cytotoxicity at the nanomolar level, and the greatest improvement in aqueous solubility came from the monosuccinate analogue (6), which was acylated on the secondary hydroxy at the 11 position. [ABSTRACT FROM AUTHOR]

Developing efficient and cost-effective methodologies for high value-added conversion of waste plastic delivers substantial environmental and economic benefits. Herein, we develop a novel approach utilizing boric acid in the methanolysis of waste polyethylene terephthalate (PET) to derive pure dimethyl terephthalate (DMT) and boronic acid esters through in-situ capture of ethylene glycol (EG). It not only upcycles waste PET but also eliminates intricate EG purification processes. Catalyzed by magnalium-aluminum-layered double oxides (Mg 4 Al 1 -LDO), this method achieved 100 % conversions of PET with 96 % and 99 % yields of arylboronic esters and DMT, respectively. Kinetic studies and in-situ Fourier-transform infrared spectroscopy (FT-IR) demonstrated the pivotal role of the monodentate methoxy species, generated through the interaction of medium basic Mg–O ion pairs and methanol. This method demonstrates applicability for the upcycling of assorted discarded PET wastes, polyesters, and polycarbonates with EG units, highlighting its potential as a comprehensive solution for waste plastic management. [Display omitted] • Full utilization of waste PET into dimethyl terephthalate and cyclic arylboronic esters is firstly proposed. • This strategy features wide substrate scope harvesting various carboxylate and arylboronic esters. • This upcycling method is highly efficient and selective, and the products can be easily separated and purified. • Monodentate methoxy intermediates plays a pivotal role in the catalytic process. • The Mg 4 Al 1 -LDO catalyst is efficient, stable, cheap, and recyclable. [ABSTRACT FROM AUTHOR]

[Display omitted] • Phenomenal patterns of aroma interactions of thioalcohols were revealed first time. • Predictive model to rapidly judge 2-furylmethanethiol interactions was established. • Determinants of interactions in a pluralistic system unearthed for the first time. This study investigated the interactions between 2-furylmethanethiol, benzenemethanethiol, and 18 skeletal aroma-active compounds as well as four aroma notes in sesame-flavor baijiu based on the Feller Additive Model, the Odor Activity Value (OAV) Approach, and the Sigma-Tau (σ-τ) plots. In addition, a predictive model for the interactions between 2-furylmethanethiol and esters was developed, and the determinants of the interaction results in complex systems were explored. The results reveal that both thioalcohols interacted with the skeletal aroma-active compounds in a similar trend, where 2-furylmethanethiol tends to enhance the release of fruit and acid aroma. Moreover, the intensity of the thiols and their intensity ratio to the notes were the determinants of the interaction results in the multivariate blended system, with the lower the concentration of the thiols, the closer the ratio was to 1, and the more likely that additive interactions would take place. Predictive modeling showed that 2-furylmethanethiols were more likely to have additive or synergistic effects with esters when the olfactory thresholds of the esters were between 75.86 and 199.53 μg/L. Conversely, masking effects were more likely. [ABSTRACT FROM AUTHOR]

• CuBr 2 /1,10-phenanthroline catalysed synthesis of α-keto esters. • Lower catalyst loading under continuous-flow conditions. • The reaction proceeds via a bromo intermediate. • Air as an oxidant. A new CuBr 2 /1,10-phenanthroline catalysed method for the synthesis of α-keto esters directly form aryl acetates is reported. The reaction proceeds via benzylic bromination, and followed by oxidation in presence of air. The reaction was carried out under a basic condition, in presence of air at 140 °C for 10 h in a batch process. The reaction in the flow reactor required lower catalyst loading, and reaction time was reduced from 10 h to 40 min. The desired α-keto esters were obtained with 55 % to 71 % yields. [Display omitted] [ABSTRACT FROM AUTHOR]

The main aim of this study is to experimentally investigate the yield of extraction and the presence of wax in the extracted yield from Musa a cuminata (banana) biomass based on various functional groups that are present in natural wax. Extraction of natural wax from Musa a cuminata (banana) biomass has been done by using the Soxhlet apparatus method in the presence of both polar (ethyl acetate and ethanol) and non-polar (toluene and hexane) solvents. The extracted yield has been found as 3.58% from hexane, 5.16% from toluene, 7.03% from ethyl acetate, and 10.26% from ethanol. The wax was also found in the extracted yield only in the case of nonpolar solvents (toluene and hexane). The novelty of this work is that Musa a cuminata (banana) waste biomass has been utilized to recover the natural wax using nonpolar solvents and also compared with that of polar solvents to check the scope of wax extraction using polar solvents. Also, statistical analysis has been performed of the extracted yield using both solvents. Thin Layer Chromatography (TLC) and Fourier Transform Infrared Spectroscopy (FTIR) methods have been used to determine the various hydrocarbon chains present in the extracted yield which is similar to that of natural wax. [Display omitted] • The extracted yield has been found to be 3.58% from hexane, 5.16% from toluene. • Beeswax is a natural product, composed of a complex mixture of non-glyceride esters. • These esters are carboxylic acids and hydroxy acids. • Chitosan and wax can be utilized for packaging applications. • The natural wax has been extracted from Musa a cuminata biomass. [ABSTRACT FROM AUTHOR]

Foothill death camas (Zigadenus paniculatus) is a common poisonous plant found throughout western North America. The toxic alkaloids in foothill death camas are zygadenine, esters of zygadenine, with zygacine, the 3-acetyl ester of zygadenine, often being the most abundant. Two additional esters of zygadenine that are found primarily in the floral parts of foothill death camas are 3-angeloylzygadenine and 3-veratroylzygadeine. Recent research has shown that very little zygacine is detected in the blood of animals dosed with zygacine. A recent investigation into the metabolism of zygacine demonstrated that zygacine is rapidly metabolized to zygadenine, demonstrating a clear first pass effect. The objective of this study was to determine if there is a difference in the acute toxicity of zygacine and zygadenine to mice and sheep. Additionally, two other esters of zygadenine, 3-angeloylzygadenine and 3-veratroylzygadenine, were evaluated for their acute toxicity in a mouse IV LD 50 assay. All three esters of zygadenine tested were more toxic than zygadenine, with the following rank order of toxicity in the mouse IV LD 50 assay: zygadenine-HCl (59.5 mg/kg) < zygacine-HCl (1.6 mg/kg) < angeloylzygadenine-HCl (1.0 mg/kg) < veratroylzygadenine-HCl (0.5 mg/kg). Similar to the results of the mouse experiments, zygacine-HCl was significantly more toxic than zygadenine-HCl in sheep dosed IV with pure compounds. Sheep dosed with 1.25 mg/kg zygacine-HCl showed severe clinical signs of poisoning. Whereas a dose of 12.5 mg/kg zygadenine-HCl was required to elicit a similar onset and severity of clinical signs. Overall, these data indicate that zygacine is more toxic than zygadenine when administered IV, when first pass metabolism is bypassed. [Display omitted] • Zygacine, zygadenine, 3-angeloylzygdenine and 3-veratroylzygadenine are alkaloids in foothill death camas. • The order of toxicity in a mouse IV LD 50 assay are zygadenine < zygacine < 3-angeloylzygdenine < 3-veratroylzygadenine. • Zygacine is rapidly metabolized to zygadenine after IV administration in mice and sheep. • Zygacine is more toxic than zygadenine in sheep when dosed IV. [ABSTRACT FROM AUTHOR]

Organophosphate esters (OPEs) are ubiquitous in surface soil, and atmospheric deposition is considered to be the major pollution source. However, the research on the environmental transport behaviors of OPEs between atmospheric deposition and soil is very limited. In this study, we investigated the contamination levels and seasonal variations of OPEs in atmospheric deposition samples (n = 33) collected from an area of South China every month between February 2021 and January 2022, and evaluated the contribution of OPEs in atmospheric deposition to soil. The concentrations of ∑ 21 target-OPEs ranged from 3670 to 18,600 ng/g dry weight (dw), with a mean of 8200 ng/g dw (median: 7600 ng/g dw). ∑ 21 target-OPEs concentrations in all atmospheric deposition samples exhibited significant seasonal differences (p < 0.05) with higher concentrations observed in winter and lower concentrations in summer. Tris(2,4-di-tert-butylphenyl) phosphate (TDTBPP) was the most dominant target OPE in atmospheric deposition (4870 ng/g dw), and its seasonal variation trend was consistent with ∑ 21 OPEs (p < 0.05). Simultaneously, in order to further explore the effect of atmospheric deposition on the levels of OPEs in soil of the study region, input fluxes and accumulation increments were estimated. Ten OPEs (including seven target OPEs and three suspect OPEs) exhibited high input flux means and accumulation increments, indicating that these compounds are prone to accumulate in soil via atmospheric deposition. It is noteworthy that the non-target phosphonate analyte bis(2,4-di-tert-butylphenyl) dibutyl ethane-1,2-diylbis(phosphonate) (BDTBPDEDBP) was detected at highest median concentration (8960 ng/g dw) in atmospheric deposition. Correspondingly, the average input flux and accumulation increment of BDTBPDEDBP were higher than those of all target and suspect OPEs. Collectively, this study quantifies the environmental transport behavior of OPEs between atmospheric deposition and soil, and provides new evidences for the fact that atmospheric deposition is the important pollution source of OPEs in soil. [Display omitted] • Atmospheric deposition and soil samples were analyzed for OPEs via a holistic screening strategy. • OPEs levels in all atmospheric deposition samples showed significant seasonal differences. • Compositions of target OPEs exhibited a clearly correlation between the two media. • Concentrations of non-target phosphonate compound were higher than those of all detected OPEs. • Ten OPEs were evaluated to be prone to accumulate in soil via atmospheric deposition. [ABSTRACT FROM AUTHOR]

Organophosphate esters (OPEs) are widely used commercial additives, but their environmental persistence and toxicity raise serious concerns necessitating associated remediation strategies. Although there are various existing technologies for OPE removal, comprehensive screening for them is urgently needed to guide further research. This review provides a comprehensive overview of the techniques used to remove OPEs from soil and water, including their related influencing factors, removal mechanisms/degradation pathways, and practical applications. Based on an analysis of the latest literature, we concluded that (1) methods used to decontaminate OPEs include adsorption, hydrolysis, photolysis, advanced oxidation processes (AOPs), activated sludge processes, and microbial degradation; (2) factors such as the quantity/characteristics of the catalysts/additives, pH value, inorganic ion concentration, and natural organic matter (NOM) affect OPE removal; (3) primary degradation mechanisms involve oxidation induced by reactive oxygen species (ROS) (including •OH and SO 4 •-) and degradation pathways include hydrolysis, hydroxylation, oxidation, dechlorination, and dealkylation; (5) interference from the pH value, inorganic ion and the presence of NOM may limit complete mineralization during the treatment, impacting practical application of OPE removal techniques. This review provides guidance on existing and potential OPE removal methods, providing a theoretical basis and innovative ideas for developing more efficient and environmentally friendly techniques to treat OPEs in soil and water. [Display omitted] • Current treatment technologies primarily focus on a single OPE pollutant. • Advanced oxidation is a common and efficient method for eliminating OPEs. • Catalysts/additives, pH, inorganic ions and NOM contents are influential factors. • Degradation pathways include hydrolysis, hydroxylation, and oxidation. • Remediation techniques for OPE pollution at actual sites remains scarce. [ABSTRACT FROM AUTHOR]