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BackgroundSynthetic chemicals are increasingly being recognized for potential independent contributions to preterm birth (PTB) and low birth weight (LBW). Bisphenols, parabens, and triclosan are consumer product chemicals that act via similar mechanisms including estrogen, androgen, and thyroid disruption and oxidative stress. Multiple cohort studies have endeavored to examine effects on birth outcomes, and systematic reviews have been limited due to measurement of 1-2 spot samples during pregnancy and limited diversity of populations.ObjectiveTo study the effects of prenatal phenols and parabens on birth size and gestational age (GA) in 3,619 mother-infant pairs from 11 cohorts in the NIH Environmental influences on Child Health Outcomes program.ResultsWhile many associations were modest and statistically imprecise, a 1-unit increase in log10 pregnancy averaged concentration of benzophenone-3 and methylparaben were associated with decreases in birthweight, birthweight adjusted for gestational age and SGA. Increases in the odds of being SGA were 29% (95% CI: 5%, 58%) and 32% (95% CI: 3%, 70%), respectively. Bisphenol S in third trimester was also associated with SGA (OR 1.52, 95% CI 1.08, 2.13). Associations of benzophenone-3 and methylparaben with PTB and LBW were null. In addition, a 1-unit increase in log10 pregnancy averaged concentration of 2,4-dichlorophenol was associated with 43% lower (95% CI: -67%, -2%) odds of low birthweight; the direction of effect was the same for the highly correlated 2,5-dichlorophenol, but with a smaller magnitude (-29%, 95% CI: -53%, 8%).DiscussionIn a large and diverse sample generally representative of the United States, benzophenone-3 and methylparaben were associated with lower birthweight as well as birthweight adjusted for gestational age and higher odds of SGA, while 2,4-dichlorophenol. These associations with smaller size at birth are concerning in light of the known consequences of intrauterine growth restriction for multiple important health outcomes emerging later in life.

During the past few decades, interest in phenolic substances in aquatic environments has increased due to their wide uses in numerous industries despite their high toxicity. This study aimed to investigate removing phenol from contaminated wastewater using synthesized nanoscale-activated carbon (AC) as a sorbent. The AC was synthesized from reed stalks as a local bio-based material using a chemical activation approach. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) in addition to the Fourier transform-infrared spectroscopy (FTIR) were applied to characterize the synthesizedAC. The study tested four different factors using the experimental statistical design, data analysis with Design Expert Software, and a central composite design (CCD) using response surface methodology (RSM) to maximize phenol elimination. These factors involved initial phenol concentration (ranging from 30 to 120 ppm), pH levels (ranging from 2 to 11), concentration of adsorbent range from 50 to 600 ppm, and reaction time range from 30 to 120 minutes. These variables were used as input data for the prediction model to determine the removal efficiency (%) of phenol. The analysis of the ANOVA was conducted to examine the model performance. The analysis results suggested that the most effective model in explaining the process of phenol elimination was the second-order quadratic model, and the predicted data strongly matched the experimental values. The findings revealed that the optimal adsorption conditions obtained from the experimental work were initial phenol concentration of 30 mg·L-1 , adsorbent dose of 600 mg·L-1, pH equal to 2, reaction time of 120 minutes, and the capacity of the adsorption was 30.0825 mg·g-1. As a consequence, the nanoactivated carbon extracted from reed stalks effectively adsorbs phenol from wastewater. [ABSTRACT FROM AUTHOR]

The spectral‐luminescence properties and photochemical conversions of phenol were analyzed for an isolated molecule as well as in water solvents in a continuum implicit model and explicit atomistic surroundings. This involved employing cut‐edge hybrid quantum‐classical methodologies to generate static optical spectra and the excited dissipative crossing potential energy curves. A combination of electronic excitations, gradient calculations, and embedding electrostatic potential fitting charges on quantum‐classical molecular dynamic propagation trajectories provided statistically averaged absorption spectra. The mixed‐reference spin‐flip multiconfigurational linear response method based on reference triplet preprocessed in the time‐dependent density‐functional theory was utilized to determine conical intersections between the lowest excited and ground states, as well as two‐stage transitions from the second excitation to the ground state. Non‐adiabatic quantum‐classical molecular dynamics defined photodissipative trajectories of excited states, their lifetimes, and crossing points through trajectory surface hopping together with the mixed‐reference spin‐flip and embedding electrostatic potential fitting approaches. Dyson orbitals of the extended Koopmans' theorem were applied to reveal the nature of molecular states at conical intersections and key points on photodynamic trajectories. Potential hydroxyl group cleavage predicted with conical intersections searching turns to "swift" OH deprotonation through |π→σOH*$$ {\upsigma}_{\mathrm{OH}}^{\ast } $$⟩ transition along photodynamic propagations in contrast with "long" processes leading to benzene ring deformation with stable OH bond. [ABSTRACT FROM AUTHOR]

Pyomelanin, a polymeric pigment in Pseudomonas, arises mainly from alterations in tyrosine degradation. The chemical structure of pyomelanin remains elusive due to its heterogeneous nature. Here, we report strain‐specific differences in pyomelanin structural features across Pseudomonas using PAO1 and PA14 reference strains carrying mutations in hmgA (a gene involved in pyomelanin synthesis), a melanogenic P. aeruginosa clinical isolate (PAM), and a melanogenic P. extremaustralis (PexM). UV spectra showed dual peaks for PAO1 and PA14 mutants and single peaks for PAM and PexM. FTIR phenol : alcohol ratio changes and complex NMR spectra indicated non‐linear polymers. UVC radiation survival increased with pyomelanin addition, correlating with pigment absorption attenuation. P. extremaustralis UVC survival varied with melanin source, with PAO1 pyomelanin being the most protective. These findings delineate structure‐based pyomelanin subgroups, having distinct physiological effects. [ABSTRACT FROM AUTHOR]

The experimental results of the present study show that phenol had a certain inhibitory effect on its utilization by phenol-acclimatized activated sludge (PAAS), which was the inoculum for the microbial fuel cell (MFC) inoculation. In co-metabolic study, utilization of para-nitrophenol (PNP) at low concentrations (< 20 mg L−1) when used with phenol at a fixed concentration (250 mg L−1) favorably proceeded. The behavior was interpreted in terms of carbon catabolite repression (CCR), indicating phenol (250 mg L−1) positively affected consumption of PNP (< 20 mg L−1). The calculated values of degradation rate show the necessity of phenol presence in the system where phenol acted on the inoculum's ability to withstand the inhibitory effect of PNP. The MFC functionality in electricity generation is also definable by considering CCR applicability and the results show that the negative effect of PNP was repressed by the presence of phenol. For instance, 20 mg L−1 PNP + 250 mg L−1 phenol yielded the highest power density (66.2 mW m−2) and the lowest internal resistance (189 Ω). The PAAS performance was characterized to evaluate cells' capacity in utilizing inhibitory substrates, and several different models were used. The relevant kinetic parameters are described in terms of PAAS affinity toward the substrate (ks) and the microbe's sensitivity in responding to the toxic substrate (ki). Luong and Aiba equations were chosen to describe MFC behavior when the PAAS utilized phenol as the sole substrate. While Haldane model was more capable of addressing co-metabolic degradation of PNP. [ABSTRACT FROM AUTHOR]

In this study, anthocyanin and phenolic compounds were extracted from pomegranate peel powder with supercritical CO2 and Lepidium perfoliatum seed gum and maltodextrin were used as the nanoencapsulation wall. The nanoencapsulation extract was dried with a freeze dryer. Color stability and antioxidant activity of nanoencapsulation extract were evaluated. The levels of anthocyanin and phenolic compounds were evaluated by differential pH and FolinCiocalteu method, respectively. Particle size, nanoencapsulation efficiency of anthocyanin, nanoencapsulation phenol, color stability at different temperatures and pH as well as antioxidant activity were evaluated by DPPH. The amount of anthocyanin and phenol extracted in this method was 3.943±0.133 mg/g of pomegranate peel powder and 504.521±2.537 mg/g of gallic acid per 100 g, respectively. Nanoencapsulation efficiency was higher for anthocyanin than phenols. The release of anthocyanin at different pHs was different, so that anthocyanin behaved differently at different pHs. Polymerization and color increased with increasing temperature. The antioxidant activity of the fine-grained extract by DPPH method increased with increasing concentration and its IC50 was equivalent to 1.092± 0.024 m /ml. [ABSTRACT FROM AUTHOR]

Substantial amounts of phenolic compounds are present in medium‐low temperature coal tar (MLCT), of which dimethylphenol (DMP) is not as valuable to be utilized as the more abundant cresol due to its complex composition and difficulty in isolation. In this study, the disproportionation and transalkylation reactions of MLCT‐related model compound, i.e., 2,6‐DMP, in phenol over zeolite catalysts are investigated using a fixed‐bed reactor for sustainable new option to utilize MLCT‐derived phenolic mixtures. Reactivity is promoted at high temperatures and associated with zeolite acidity and pore structure. Since disproportionation and transalkylation reactions have certain spatial requirements, the micropores of MFI‐type zeolite may cause spatial barriers that make it difficult to carry out the reactions. MCM‐22, characterized by MWW‐type zeolite, maximized the conversion of 2,6‐DMP due to its strong Bronsted acidity and large mesopore volume. FAU‐type zeolite HY with a 3D large 12‐ring through‐channel shows relatively small spatial confinement and certain molecular sieving ability, which enables bimolecular reactions while allowing cresols to flow out of the pores efficiently to obtain the highest cresol selectivity. The addition of phenol significantly inhibits the spontaneous disproportionation of 2,6‐DMP to tricresol. Besides, o‐cresol dominate the cresol products, suggesting that the selectivity of o‐cresol is kinetically controlled. [ABSTRACT FROM AUTHOR]

The Kingdom of Saudi Arabia (KSA) has millions of date palm trees for commercial scale date-fruit production. The respective industry also generates agricultural waste including date palm tree branches. This rich bio-resource can be used for several beneficial applications. The present study therefore investigated the application of granular activated carbon (GAC) produced using date palm tree branches to successfully remove phenol, p-cresol, and copper from synthetic wastewater. The respective adsorption equilibrium results fitted well to the Langmuir-type adsorption isotherm. Furthermore, the pH-dependent adsorption results both for phenol and p-cresol appeared to follow an anionic-type adsorption behavior (i.e., decreasing adsorption with an increase in aqueous phase equilibrium pH). However, the pH-dependent adsorption finding for copper showed a cationic-type adsorption behavior. These adsorption trends were explained employing the pH-dependent speciation of the respective pollutants. In general, findings from the present work indicate that a high-specific-surface-area (SSABET) GAC material from the date palm tree branches can be successfully employed for aqueous phase pollution control. [ABSTRACT FROM AUTHOR]

This paper aimed to enhance the particle properties of refuse-derived fuel by means of ultrasonic pretreatment and discussed the effect of pretreatment on the pyrolysis products. Firstly, the ultrasonic pretreatment improved the physical properties of refuse-derived fuel. Molding experiments demonstrated that the natural binder component of refuse-derived fuel extruded from the cells after ultrasonic pretreatment, forming a vitreous layer, mechanical interlocking bonds, and fixed bridges between the particles. The impact resistance index could be increased from 0 to 185.71 at most, the extending rate could be reduced by up to 18.38%, and the particle density could be increased by 4.40%. The results of pyrolysis tests showed that ultrasonic pretreatment promoted the formation of phenol with a maximum increase of 14.94%. Besides, the acoustic physical effect and microjets generated by ultrasonic formed multiple porous and multilayer structures on the surface of the pyrolysis char. Overall, ultrasonic pretreatment could improve the pellet characteristics of refuse-derived fuel without adding binders and convert its pyrolysis products into valuable chemicals. [ABSTRACT FROM AUTHOR]

Triclosan, like many other aromatic halides, plays an important role industrially and inevitably ends up in the environment. Chemical treatments have effectively mitigated the presence of such chemicals, through using harsh oxidizing treatments, which are not without issues. A milder and greener alternative, such as an electrochemical method, is needed for the mitigation of compounds, such as triclosan. Herein, we evaluated triclosan treatment via electrochemical cycling and compared it to a traditional chemical oxidative process. Cyclic voltammetry was carried out using a three-electrode cell containing glassy carbon, silver wire, and platinum wire in organic solvent. Electrochemical cycling revealed 6 × greater triclosan conversion compared to traditional chemical oxidation reaction, as monitored by UV–Vis spectroscopy. In terms of reaction product selectivity, the chemical and electrochemical reactions yielded the oxidized triclosan and an ether cleavage product, dichlorophenol, as determined by gas chromatography–mass spectrometry. Of note, the chemical oxidation yielded the chlorinated re-dimerization side product, which was not observed during electrochemical cycling, which is beneficial, as such products have to be degraded again. Overall, our findings indicate that electrochemical methods offer significant advantages over traditional organic methods, such as product selectivity, relative conversion, and greener operation. In addition, electrochemical approaches offer tunability, such as electrode material, electrolyte, solvent, potential, or current applied, all of which may be integrated into a more efficient environmental application. [ABSTRACT FROM AUTHOR]

Exploring effective transition metal single-atom catalysts for selective oxidation of benzene to phenol is still a great challenge due to the lack of a comprehensive mechanism and mechanism-driven approach. Here, robust 4N-coordinated transition metal single atom catalysts embedded within graphene (TM1-N4/C) are systematically screened by density functional theory and microkinetic modeling approach to assess their selectivity and activity in benzene oxidation reaction. Our findings indicate that the single metal atom triggers the dissociation of H2O2 to form an active oxygen species (O*). The lone-electronic pair character of O* activates the benzene C-H bond by constructing C-O bond with C atom of benzene, promoting the formation of phenol products. In addition, after benzene captures O* to form phenol, the positively charged bare single metal atom activates the phenol O-H bond by electron interaction with the O atom in the phenol, inducing the generation of benzoquinone by-products. The activation process of O-H bond is accompanied by H atom falling onto the carrier. On this basis, it can be inferred that adsorption energy of the C atom on the O* atom (EC) and the H atom on the TM1-N4/C (EH), which respectively represent activation ability of benzene C-H bond and phenol O-H bond, could be labeled as descriptors describing catalytic activity and selectivity. Moreover, based on the as-obtained volcano map, appropriate EC (−8 to −7 eV) and weakened EH (−1.5 to 0 eV) contribute to the optimization of catalytic performance for benzene oxidation to phenol. This study offers profound opinions on the rational design of metal single-atom catalysts that exhibit favorable catalytic behaviors in hydrocarbon oxidation. [ABSTRACT FROM AUTHOR]

ABSTRACT This study aimed to study the impact of Ferulago angulata (Schlecht) Boiss (known as an antioxidant known as Chavir) extract, obtained through ultrasound‐assisted extraction (UAE), on the physicochemical, antioxidant and sensory properties of virgin olive oil (VOO) during a 90‐day storage period at room temperature. For this purpose, different concentrations of Chavir extract (100, 200 and 300 ppm) were added to VOO. Key parameters, including total phenol content (TPC), extract composition by HPLC‐DAD and quality indicators like acidity value (AV), p‐anisidine value (p‐AV) and UV indices (parameters: K232, K270 and ΔK), were determined. AVs increased overall during the storage period, but adding Chavir extract at 300 ppm appeared to counteract the rise in free fatty acids, suggesting a potential role in reducing hydrolysis. p‐AVs decreased in unflavoured and flavoured samples, indicating reduced oxidation in Chavir‐flavoured VOO. K232 values exhibited a decline in the presence of flavouring agents and their concentrations. In contrast, the values of K270 showed an increase over the storage period, which indicated the formation of aldehyde and ketones in the second oxidation step. All samples maintained ΔK values below permissible limits (≥ 0.01), signifying good stability. The sensory evaluation emphasised positive attributes such as bitterness, fruitiness and pungency, indicating the high quality of VOO. The addition of Chavir extract further enhanced all of these positive characteristics, particularly at the 300 ppm concentration. However, a gradual decline was observed in all these attributes over time. Notably, the Chavir extract played a crucial role in delaying the formation of secondary oxidation products, which contribute to negative attributes like rancidity in VOO. Moreover, adding Chavir extract increases oxidative stability, infuses the positive qualities in VOO and provides valuable insights into its potential applications for enhancing the overall quality of VOO during storage. This enhancement not only helps maintain high quality and nutritional value but also makes the product more appealing to consumers. [ABSTRACT FROM AUTHOR]

Supercritical water (SCW) gasification technology can enable the efficient utilization of coal by converting it to hydrogen-rich gas. However, poly-cyclic aromatic hydrocarbons and heavy components, which are intermediates of supercritical water gasification, tend to generate char, hindering the complete gasification of coal. In this work, phenol is recycled to enhance the gasification process and reduce the formation of these intermediates during SCWG, and the regulation mechanism is investigated. The results demonstrate that both gas yield and gasification efficiency increase with the presence of phenol, reaching approximately 98.5% at 750 °C, concentration of 2%with the effect of phenol, which is 27% higher than that in the coal-water system. Organics removal rate reaches about 98% with the addition of phenol. Phenol can enhance the gasification performance by facilitating the conversion of heavy components to lightweight components. The transient reactivity of coal in the poly-condensation stage is increased by about 50 times with the presence of phenol. The regulation mechanism of phenol in the poly-condensation stage during coal gasification involves the decomposition of SCW forming hydroxyl radicals, which replaces the substituents on the benzene ring, facilitating the dissociation of benzene ring into small molecules that are prone to polymerize. The interacting force between phenol and multi-rings disrupts the conjugate structure, aiding in the decomposition of polycyclic organics into small molecules. • Investigated the regulating mechanism of phenol on the gasification process. • Hydrogen yield and gasification efficiency increases with the presence of phenol. • Nearly complete gasification (98.5%) is realized with the presence of phenol. • The organics removal rate reaches about 98% with the presence of phenol. • Reactivity of coal in the polycondensation stage increased by 50 times with phenol. [ABSTRACT FROM AUTHOR]

The Folin-Ciocalteu method is a well-established and widely used assay for measuring total (poly)phenol content in food/plant products. In recent years, there has been growing interest in applying this method to human samples due to its simplicity and efficacy. However, biological matrices such as blood and urine contain several interference substances that must be eliminated beforehand. This mini-review summarizes the current state of knowledge regarding the use of the Folin-Ciocalteu assay to measure total phenolic content in human urine and blood samples, as well as the preceding cleaning methods to remove interferences. Higher total (poly)phenol levels measured by the Folin-Ciocalteu method have been associated with a decrease in mortality and several risk variables. We focus on the application of this sustainable assay as a biomarker of poly(phenol) intake and its potential use as an anti-inflammatory biomarker in clinical laboratories. The Folin-Ciocalteu method, with a clean-up extraction step, is a reliable tool for determining total (poly)phenol consumption. Here, we also recommend using the Folin-Ciocalteu assay as means to measure anti-inflammatory activity. [ABSTRACT FROM AUTHOR]

Direct aromatization of cyclohexanones to synthesize substituted phenols represents a significant challenge in modern synthetic chemistry. Herein, we describe a novel ene‐reductase (TsER) catalytic system that converts substituted cyclohexanones into the corresponding phenols. This process involves the successive dehydrogenation of two saturated carbon‐carbon bonds within the six‐membered ring of cyclohexanones and utilizes molecular oxygen to drive the reaction cycle. It demonstrates a versatile and efficient approach for the synthesis of substituted phenols, providing a valuable complement to existing chemical methodologies. [ABSTRACT FROM AUTHOR]

Electrocatalytic oxidation of aqueous phenol to para‐benzoquinone (p‐BQ) offers a sustainable approach for both pollutant abatement and value‐added chemicals production. However, achieving high phenol conversion and p‐BQ yield under neutral conditions remains challenging. Herein, we report a Ni(OH)2‐supported Ru nanoparticles (NiRu) hybrid electrocatalyst, which exhibits a superior phenol conversion of 96.5 % and an excellent p‐BQ yield of 83.4 % at pH 7.0, significantly outperforming previously reported electrocatalysts. This exceptional performance benefits from the triple synergistic modulation of the NiRu catalyst, including enhanced phenol adsorption, increased p‐BQ desorption, and suppressed oxygen evolution. By coupling a flow electrolyzer with an extraction‐distillation separation unit, the simultaneous phenol removal and p‐BQ recovery are realized. Additionally, the developed electrocatalytic system with the NiRu/C anode displays good stability, favorable energy consumption, and reduced greenhouse gas emissions for phenol‐containing wastewater treatment, demonstrating its potential for practical applications. This work offers a promising strategy for achieving low‐carbon emissions in phenol wastewater treatment. [ABSTRACT FROM AUTHOR]

Aim: In recent years, the paradigm for the treatment of sacrococcygeal pilonidal sinus disease (SPSD) has shifted from surgical excision toward more minimally invasive techniques. Although extensive research has been conducted on the minimal invasive phenolization technique for primary SPSD, literature in recurrent SPSD is lacking. The purpose of this study was to report the long-term outcomes of the phenolization technique for recurrent SPSD. Method: This study included all 57 patients who were initially prospectively included in this study for short-term follow-up after phenolization for recurrent SPSD. A questionnaire was sent out to all patients to obtain long-term outcome. The primary endpoint was recurrence. Secondary endpoints included quality of life and symptoms related to SPSD. Results: A total of 47 patients (82.5%) were available for long-term follow-up. Recurrence needing further surgery developed in 7 patients (14.9%) after a mean follow-up of 76 (SD 21.7) months. At follow-up, there was improvement in the quality of life compared to preoperative levels (82.0, IQR 75.0–90.0 versus 74.0 IQR 52.5–80.0, p = 0.024). Additionally, symptoms associated with SPSD, including pain, fluid discharge, and itching sensation, also showed significant improvement. A total of 42 patients (89.4%) would undergo the same treatment again. No significant association was found between known risk factors and recurrence. Conclusion: Phenolization for recurrent SPSD showed a recurrence rate of 14.9% with significant improvement of natal cleft symptoms and quality of life at long-term follow-up. Therefore, phenolization should be considered as a feasible option for patients with recurrent SPSD. [ABSTRACT FROM AUTHOR]

A catalytic system comprising a gold(I) complex with an N‐heterocyclic carbene (NHC) ligand in an ionic liquid as solvent exhibits higher catalytic efficiency compared to state of the art systems in the title reaction, which enables using down to 0.01 mol % gold. A commercial gold(I) catalyst such as IPrAuNTf2 can be employed for this purpose. In the case of less reactive substrates bearing electron‐withdrawing substituents at the phenol moiety, a tailor made NHC‐gold(I) precatalyst exhibits improved reactivity and can be advantageously employed compared to the commercial one. [ABSTRACT FROM AUTHOR]

Phenols play a crucial role as core structural motifs in natural products and also serve as fundamental building blocks in synthetic chemistry. Apart from the known protocols for the conversion of aryl precursors to phenols (i. e., decarboxylative oxygenation), we report here the efficient synthesis of phenols from the stable and readily available benzylic carboxylic acids under mild reaction conditions. The photocatalytic conversion of carboxylic acids to peroxides is a crucial step in this strategy, allowing the subsequent C−O bond formation via Hock rearrangement. [ABSTRACT FROM AUTHOR]

Activated carbons were prepared from kenaf (Hibiscus cannabinus L.). Carbonization was carried out at 600 °C for 2 h, and activation was performed using air at 600 °C and using CO2 at 750 °C. The activated carbons obtained were treated with HNO3 and H2SO4. The samples were characterized by their chemical and physical structure. The activated carbons obtained were mainly macroporous, and their structure underwent major changes with the activation method and acid treatment. Activated carbons were alkaline and acid-treated carbons were neutral. They were used for phenol adsorption and a kinetic and mechanistic study of adsorption was carried out. The fit to the pseudo-second order and Elovich models was predominant. The rate-limiting step of the process was determined to be diffusion within the pores, as the experimental data fit the Bangham model. DFT simulation showed that the preferred adsorption position involves π-π stacking and that oxidation enhances this interaction. Furthermore, the simulation showed that the interaction of phenol with oxygenated functional groups depends on the type of functional group. [ABSTRACT FROM AUTHOR]

To evaluate the inheritance of natural durability of Acacia mangium Willd., wood-color parameters (Y [lightness], x [red to green], and y [yellow to blue]), mass loss by a white-rot fungus (Trametes versicolor) and brown-rot fungus (Fomitopsis palustris), and three different extracts (methanol extract, total phenol, and total flavanol content) were measured using the inner and outer heartwood of 10-year-old trees from 20 half-sib families in the third-generation A. mangium in Indonesia. The broad-sense heritability (H2) values were moderate to high for the wood-color parameters and mass loss by white- and brown-rot fungi (H2 = 0.210–0.851) and low to moderate for three different extracts (H2 = 0.000–0.576). Significant negative phenotypic correlations were found between the three different extracts and mass loss by T. versicolor and F. palustris. In addition, negative correlations were found between the wood-color parameters and three different extracts. Similar results were found between the total phenol content and y and between the total flavanol content and Y in genetic correlations. Therefore, A. mangium families with lower Y and y in heartwood could produce progenies with higher total phenol and total flavanol content, leading to higher natural decay resistance. [ABSTRACT FROM AUTHOR]

Hierarchically structured materials are considered to be one of the important options to enhance the mass transportation efficiency in microporous zeolites. Herein, we reported a highly efficient steam-assisted crystallization strategy for the synthesis of a hierarchical TS-1 zeolite with a tunable macropore size. The amorphous SiO2–TiO2 precursor dissolved gradually and acted as both a nutrient supplier and macropore template in situ. The framework Ti content of the synthesized TS-1 zeolites could be tuned over a wide range (Ti wt% = 0.70–1.39) by varying the Ti content of the SiO2–TiO2 precursor. Moreover, the pore size of the macropores could be modulated according to the particle size of the precursor based on the investigation of the formation mechanism of the macropores in the hierarchical TS-1 zeolite. The hierarchical TS-1 zeolite exhibited better catalytic activity in the epoxidation reaction of 1-hexene and hydroxylation of phenol compared to the typical microporous zeolites. The improved performance of the hierarchical TS-1 zeolite was probably caused by the improved diffusion performance of the hierarchical structure. [ABSTRACT FROM AUTHOR]

Herein we report a new, practical and efficient preparation of benzofuran-3-carboxylates and naphthofuran-3-carboxylates starting from β-nitroacrylates and phenols. The reaction is promoted by indium trichloride and leads to the target compounds in good to very good yields under microwave irradiation. [ABSTRACT FROM AUTHOR]

AbstractThe market for olive leaf dietary supplements is expanding rapidly and is valued at $437.15 million today. However, information on the control of these products is sketchy and the origin and variety of olives are rarely stated. The aim of this research was to validate a simple and rapid screening method for oleuropein determination in olive leaf dietary supplements. A matrix blank was prepared by removal of oleuropein from a mixture of dietary supplements and the matrix was then spiked with known concentrations to create a spiked matrix calibration curve in the range 5 - 40% oleuropein. Five replicate extractions and analyses of the matrix standards were carried out over 10 days. Precision was less than 6% RSD and linearity was demonstrated by the Fischer test. Extraction recovery was > 90% and there was a strong linear relationship between authentic and matrix standards. All tested products conformed to the label claim which was strongly correlated with total polyphenols measured by the Folin-Ciocalteau method. Antioxidant activity was measured by the DPPH assay and was found to be strongly correlated with total phenol content and oleuropein concentration. [ABSTRACT FROM AUTHOR]

In this study, a series of high-efficient catalyst, Co–Fe/Al 2 O 3 , were synthesized via the sol-gel method for low-temperature phenol steam reforming (PSR). The optimized catalyst, 15Co–2Fe/Al 2 O 3 , exhibited a remarkable phenol conversion of 95.3%, a H 2 yield of 92.1% at 450 °C, GHSV = 7500 h−1 and a steam-to-carbon (S/C) ratio of 10. Furthermore, the catalyst activity was maintained for 660 min before a gradual decline was observed. The NH 3 -TPD analysis revealed that the addition of Fe enhanced the surface acidity of the catalyst, providing more active sites for phenol adsorption and activation. This study aims to address the challenges associated with high reaction temperatures and poor catalyst stability in PSR. Various characterization techniques have been employed to investigate the reaction mechanisms of bimetallic catalysts in low-temperature PSR. [Display omitted] • Doping with Fe enhances the catalytic activity of the catalyst at high GHSV. • Doping with Fe enhances the catalytic activity of the catalyst at low temperature. • Fe doping enhances adsorbate-catalyst interaction. [ABSTRACT FROM AUTHOR]

In this work, silyl ethers of phenols and alcohols have been successfully prepared and tested as neutral carbon (silicon) centered radical precursors. The organophotocatalyzed oxidation (by the Fukuzumi catalyst) of these ethers caused the cleavage of a C−Si (or a Si−Si) bond for the release of the desired radical to be used for the forging of C(sp3) −C(sp3) (or C(sp3) −Si) bonds via a Giese reaction. [ABSTRACT FROM AUTHOR]

Background: Watermelon (Citrullus lanatus) consists of peel and rind (30-40% of total fruit weight), commonly discarded as waste. Nonetheless, several studies have shown the potential benefit of these watermelon parts. This study aimed to determine the correlation between the watermelon cultivation areas and their chemical composition, especially phenols and flavonoids. Watermelon peel and rind were obtained from Jember (WJ), Sragen (WS), Langkat (WL), Hulu Sungai Tengah (WHST) and Lombok Tengah (WLT). Methods: The total phenols and flavonoids were determined by using the colorimetric method. Furthermore, the antioxidant activity was determined by using DPPH and ABTS methods. Result: The highest total flavonoids, i.e. 41.86±1,65 mgQE/100 g watermelon, was observed in the WHST rind. While WL peel showed the highest total phenols, i.e. 3.97±0.02 mgGAE/g. The correlation analysis for all samples showed no significant relationship between the antioxidant activity and total flavonoids. However, a significant relationship was found between the DPPH-IC50 and total phenols with a correlation value of 0.47 (p<0.01) for both watermelon parts peel and rind. In addition, watermelon peel contains higher total flavonoids compared to rind. But, there was no significant difference in the total phenols between the watermelon peel and rind. To conclude, both watermelon peel and rind obtained from five cultivation areas showed antioxidant activities contributed by the phenolic compounds. [ABSTRACT FROM AUTHOR]

A field experiment was carried out to assess the susceptibility of 14 different cauliflower genotypes against infestation by cabbage butterfly. Throughout the growing season of the crop, observations on larval infestation were made by assessing the presence of larvae on randomly selected and tagged plants. The total concentrations of glucosinolates and phenols in the leaves of different varieties were determined. Glucosinolate concentration was estimated by processing samples in triplicates and measuring content by spectrophotometry method utilising a Na2PdCl4 assay, with sinigrin standards for calibration. The estimation of total phenols from field collected samples on the other hand, was carried out using an 80% ethanol extraction method. Following the grinding of samples and ethanol extraction, samples were processed using Folin-Ciocalteau reagent and sodium carbonate. This was followed by spectrophotometric measurement at 650 nm, performed to estimate the phenol content via a pyrogallol standard curve. Statistical analysis demonstrated a significant negative correlation (r = -0.985) between cabbage butterfly infestation and total glucosinolate content. Conversely, a significant positive correlation (r = 0.901) was observed between total phenols and cabbage butterfly infestation. It was found that the Pusa Snowball-1 genotype had the lowest mean larval population at 21.66 and the lowest total glucosinolate content (9.35 µmoles/g). In contrast, the Olympus genotype, which had the highest total phenol concentration of 931.42 mg/100 g, exhibited the highest mean larvae per plant at 30.86. This study underscores the crucial role of host-plant resistance in pest management, highlighting that variations in glucosinolate and phenol content among different cauliflower genotypes significantly influence susceptibility to cabbage butterfly infestation. [ABSTRACT FROM AUTHOR]

The objective of this investigation was studying the Physicochemical characteristics and microbiological stability of five innovative fruit sheets containing red beetroot puree (RBRP) and pomegranate juice (PJ) in ratios of 100:0, 75:25, 50:50, 25:75, and 0:100 during 6-month storage at room temperature (25–30ºC). The results showed that moisture content (ranging from 14.64% to 14.96%), water activity (ranging from 0.638 to 0.642), total phenols (ranging from 18.94 to 19.20 mg GAE/g), total flavonoids (ranging from 16.50 to 16.59 mg rutin [RE]/g), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (ranging from 73.66% to 77.02%), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging activity (ranging from 50.13% to 52.09%) in 100% RBRP sheets were more than in 100% PJ sheets. In contrast, 100% RBRP sheets had a lower pH (ranging from 4.09 to 4.13), total soluble solids (TSS) (ranging from 63.99 Brix to 65.08 Brix), total sugars (ranging from 59.58% to 59.90%), and hardness (ranging from 12.88 N to 14.10 N) than that of 100% PJ sheets. In addition, the findings revealed that at zero time when the replacement percentage of PJ for RBRP increased in the sheets formula from 25% to 100%, there was increase in TSS (from 65.11 Brix to 67.41 Brix), acidity (from 1.03% to 1.90%), total sugars (from 59.29% to 61.72%), and hardness (from 12.27 N to 13.85 N) as well as decrease in moisture content (from 15.01% to 14.75%), water activity (from 0.652 to 0.630), total phenols content (18.71 to 17.01 mg GAE/g), total flavonoids content (15.74 to 12.97 mg RE/g), DPPH scavenging activity (from 72.19% to 63.28%), ABTS scavenging activity (from 50.86% to 44.28%), and L* value (from 22.80 to 21.86). Significant decrease (p ≤ 0.05) was observed in pH, moisture, water activity, total sugars, total phenol contents, total flavonoid contents, and antioxidant activity during the storage period. All sheets were found to be extremely sensory-acceptable and microbiologically safe. In conclusion, RBRP and PJ or a mix of them could be used as functional sheets with high storage stability. [ABSTRACT FROM AUTHOR]

It has been established that the maximum synergistic effect (more than 100%) is characteristic of the binary mixtures of pentadigalloyl glucose mixed with protocatechuic and vanillic acids in a ratio of 90 : 10 vol % in the reaction with the 2,2'-diphenyl-1-picrylhydrazyl radical in benzene. With an increase in the polarity of the solvent (dimethyl sulfoxide), an increase in the maximum synergistic effect by 15–20% on the average is observed. Using the methods of quantum chemical calculations and difference UV spectroscopy, it is shown that the resulting effect of the compositions of pentadigalloyl glucose with monomeric phenols depends on the following two mechanisms of synergistic action: the first mechanism is related to the formation of the intermolecular H-complex between reagents, which exhibits higher antiradical activity than that of the initial compounds; the second one is associated with the reduction of oxidized forms of the weaker antioxidant (monomeric phenol) by the stronger antioxidant (pentadigalloyl glucose). The mixture of pentadigalloyl glucose with methoxylated forms of plant phenols is a promising synergistic composition with high antiradical activity. [ABSTRACT FROM AUTHOR]

The present study evaluates the effect of Eryngium billardieri alcoholic extract (EBAE) at weight/volume levels of 0.5% and 1% on some physicochemical, sensory, and microbial properties of cow milk. Results showed that adding EBAE reduced the samples' pH, lightness index (L*), and whitening index (WI). Besides, it increased the levels of acidity, dry matter, viscosity, color indices a* and b*, total phenol content (TPC), total flavonoid content (TFC), antioxidant activity (AA), and enzyme inhibitory activity (EIA) of the fortified milk samples than the control sample (p <.05). During the storage period, a decrease in TPC, TFC, AA, and EIA was observed in all samples (p <.05). There was a positive direct relationship between the health activity of EBAE and its concentration. Moreover, EBAE was able to reduce the total microbial count (TMC) in the milk samples (p <.05). The sample containing 1% w/v of EBAE had the highest TPC, TFC, AA, and EIA but the lowest TMC, and it was highly acceptable in terms of sensory evaluation. Therefore, this sample was selected as the best treatment in this study. The results of this study confirm that EBAE may be used to improve antioxidant activity and beneficial effects in milk. [ABSTRACT FROM AUTHOR]

Poly(p-dioxanone) (PPDO) is crystallized with amorphous poly(p-vinyl phenol) (PVPh) and tannic acid (TA) as co-diluents to regulate and induce dendritic-ringed PPDO spherulites, with spoke- or sector-bands, aiming for convenience of analyses on interior lamellar assembly. Morphologies and interior lamellar arrangement leading to the peculiar rings on individual dendrites are evaluated by using polarized-light microscopy (PLM) and scanning electron microscope (SEM). Combinatory microbeam small-/wide-angle X-ray scattering (SAXS/WAXS) analyses further confirm the unique assembly patterns in periodic cycles. Alternate gratings are packed with periodic ridges composed of feather-like branches and the valley is featured with some embossed textures. The periodic gratings in the ringed spokes resemble those in nature's structured coloration and are proven to display light-interference iridescence. [ABSTRACT FROM AUTHOR]

A sensitive analytical procedure for simultaneous extraction and determination of bisphenol A and alkyl phenols, namely, 4‐sec‐butylphenol, 4‐tert‐butylphenol, and 4‐tert‐amylphenol from aqueous samples with metal–organic framework (MOF)‐based dispersive micro‐solid‐phase extraction (D‐µSPE) and high‐performance liquid chromatography (HPLC) technique is developed. Sample contaminants were preconcentrated with amino‐functionalized aluminum MOF and later eluted with acetonitrile. The reconstituted sample was subjected to HPLC analysis. Various procedural parameters related to D‐µSPE were optimized. Under optimized preconcentration and chromatographic conditions, calibration curves with excellent linearity (R2 > 0.9986) in the working range of 0.25–100 ng mL−1 were prepared. Limit of detection (S/N = 3) for every analyte within the range of 0.020–0.022 ng mL−1 was obtained. Analyte's recovery 91.16%–97.01% (RSD = 1.02–3.01) for intraday and 89.86%–95.83% (RSD = 1.15–3.13) for inter‐day analysis was obtained from real water samples. [ABSTRACT FROM AUTHOR]

Herein, we report an efficient method to access difluoromethyl ethers of thiols and phenols using ethyl bromodifluoroacetate and K2 CO3. This method demonstrates chemoselective difluoromethylation of thiols and phenols in the presence of amines. The current method also discloses the synthesis of bis(aryloxy)fluoromethane compounds which are least reported in the literature. Mechanistic investigations revealed that the reaction proceeds through a nucleophilic substitution pathway. We strongly believe this protocol would offer an efficient alternative to earlier photocatalyzed or radical-mediated difluoromethylation methods and it has a great potential in the scale-up of pharmaceutical and agrochemical intermediates that possess difluoromethyl group. [ABSTRACT FROM AUTHOR]

Herein, we report an efficient method to access difluoromethyl ethers of thiols and phenols using ethyl bromodifluoroacetate and K2 CO3. This method demonstrates chemoselective difluoromethylation of thiols and phenols in the presence of amines. The current method also discloses the synthesis of bis(aryloxy)fluoromethane compounds which are least reported in the literature. Mechanistic investigations revealed that the reaction proceeds through a nucleophilic substitution pathway. We strongly believe this protocol would offer an efficient alternative to earlier photocatalyzed or radical-mediated difluoromethylation methods and it has a great potential in the scale-up of pharmaceutical and agrochemical intermediates that possess difluoromethyl group. [ABSTRACT FROM AUTHOR]

The development of new catalytic systems based on cobalt and iron compounds for the production of oxygen-containing compounds is an urgent task of chemical technology. The purpose of this work is the synthesis of CoFe2O4 stabilized with polyvinylpyrrolidone (PVP), the study of the catalyst by physico-chemical research methods, and the determination of the effectiveness of the CoFe2O4/PVP catalyst in the phenol oxidation reaction. In this work, magnetic composites CoFe2O4 and CoFe2O4 stabilized with polyvinylpyrrolidone were synthesized by co-deposition. A comparison of the characteristics of the properties of the synthesized cobalt (II) ferrite (CoFe2O4) and the composite material CoFe2O4/PVP based on it is carried out. The obtained samples were examined using X-ray phase analysis (XRD), the Debye–Scherrer method, scanning electron microscopy (SEM), Mossbauer and IR Fourier spectroscopy, as well as thermogravimetric analysis (TGA). The textural properties were determined based on the analysis of nitrogen isotherms. The catalytic properties of the synthesized materials in the process of phenol oxidation in the presence of hydrogen peroxide are considered. The analysis of the reaction mixtures by HPLC obtained by the oxidation of phenol in the presence of a CoFe2O4/PVP catalyst showed a decrease in the concentration of phenol in the first 15 min of the process (by 55–60%), and then within 30 min, the concentration of phenol decreased to 21.83%. After 2 h of the process, the conversion of phenol was already more than 95%. The final sample after the reaction contained 28% hydroquinone and 50% benzoquinone. It was found that the synthesized magnetic composites exhibit catalytic activity in this process. [ABSTRACT FROM AUTHOR]

Phenolic pollutants are widespread in aquatic environments and are major contributors to groundwater pollution. In the present study, a new strain of Bacillus cereus, STV1713, isolated from petroleum-contaminated soil, was found to utilize phenol and 2,4-dichlorophenol (2,4-DCP) as sole carbon and energy sources. Response surface methodology analysis revealed that the optimal temperature and pH combination for this bacterium to degrade phenol and 2,4-DCP is 32.5 °C and 7.0, respectively. Under optimized conditions, it could tolerate higher phenol and 2,4-DCP concentrations up to 1400 ppm and 1200 ppm, respectively, while maximum phenol and 2,4-DCP degradation capabilities were observed until 1200 ppm and 1000 ppm, respectively. Metabolic pathway analysis by enzyme assay revealed that the bacterium uses the meta-cleavage pathway to utilize both pollutants. GC/MS analysis showed a significant reduction in the phenol concentration up to 99.51% and 2,4-DCP up to 99.13% after 72 h of degradation. The degradation ability and pollutant tolerance of B. cereus STV1713 were significantly increased after cell immobilization with sodium alginate beads. The bacterium survived up to 1800 ppm phenol and 1600 ppm 2,4-DCP after immobilization, significantly higher than the tolerance of the free cells. Among the 1023 genes identified by transcriptome analysis during phenol degradation, 40 genes were significantly differentially expressed in B. cereus STV1713 compared to the control. Phenol hydroxylase and catechol 2,3-dioxygenase were recognized as the key enzymes of phenol degradation in B. cereus STV1713. [ABSTRACT FROM AUTHOR]

Producing biomass‐derived chemicals to substitute their petrochemical counterparts has long been an aspiration of the green chemistry research community. However, synthesizing secondary amines from biomass precursors presents several challenges related to catalyst nature and the mechanistic understanding of reaction systems. Here, we unravel the mechanistic and kinetic implications of the reductive amination of phenol with cyclohexylamine over Pd/C and Rh/C. A competitive Langmuir‐Hinshelwood reaction model well interpreted the kinetic data, suggesting that support‐metal interfaces serve as active sites for H2, ─NH2 and ═NH activation. The apparent activation energies for imine hydrogenation were 87.6 kJ mol−1 (Pd/C) and 34.5 kJ mol−1 (Rh/C), while ΔHads and ΔSads values confirmed the physicochemical consistency of the model. Moreover, the catalysts demonstrated their high stability to operate for several catalytic cycles, with minor activity losses due to metal leaching and partial sintering of Pd nanoparticles. Despite phenol reductive amination following similar mechanisms on Rh/C and Pd/C, they show differences in selectivity because the hydrogenation of imine is more efficient on Rh0 than on Pd0. This is the first mechanism‐oriented kinetic study for phenol reductive amination; thus, it provides valuable information for process design and scale‐up. [ABSTRACT FROM AUTHOR]

The rate constants for the reaction of hydroperoxyl (or perhydroxyl) radical HOO˙ with fifteen phenols and ascorbyl palmitate were measured in acetonitrile at 37 °C by evaluating the effect that the antioxidants had on the rate of autoxidation of γ-terpinene. The HOO˙ radical represents an important reactive species that can be formed by protonation of superoxide anions (O2˙−) or by fragmentation of alkylperoxyl radicals (ROO˙) formed during the autoxidation of pro-aromatic derivatives like γ-terpinene. The phenols investigated in this study include natural compounds like phenolic acids (protocatechuic, caffeic and dihydrocaffeic acids), flavonoids (3-hydroxyflavone, pinobanksin, galangin, catechin, luteolin, quercetin, 6-methoxyluteolin), 4-methylcatechol and antioxidant additives ascorbyl palmitate and the a-tocopherol analogue 2,2,5,7,8-pentamethyl-6-chromanol. The rate constants for the reaction of HOO˙ with the above compounds (kinh) spanned from 1 × 103 M−1 s−1 for the unsubstituted phenol, to 7 × 104 and 9 × 104 M−1 s−1 for 4-methylcatechol and ascorbyl palmitate, respectively. As in a typical Evans–Polanyi plot, the log(kinh) was found to be inversely proportional to the bond dissociation enthalpy of the reactive OH. The comparison of the results with the data reported in the literature shows an unusual kinetic solvent effect that enlightens the unique behavior of HOO˙ and provides a rationale for the superior radical trapping ability of catechols and ascorbyl palmitate. [ABSTRACT FROM AUTHOR]

This study examined the phenol degradation capabilities and oxidative stress responses of Candida tropicalis SHC-03, demonstrating its metabolic superiority and resilience compared to Saccharomyces cerevisiae BY4742 in a culture medium with phenol as the sole carbon source. Through comparative growth, transcriptomic, and metabolomic analyses under different phenol concentrations, this study revealed C. tropicalis SHC-03's specialized adaptations for thriving in phenol as the sole carbon source environments. These include a strategic shift from carbohydrate metabolism to enhanced phenol degradation pathways, highlighted by the significant upregulation of genes for Phenol 2-monoxygenase and Catechol 1,2-dioxygenase. Despite phenol levels reaching 1.8 g/L, C. tropicalis exhibits a robust oxidative stress response, efficiently managing ROS through antioxidative pathways and the upregulation of genes for peroxisomal proteins like PEX2, PEX13, and PMP34. Concurrently, there was significant upregulation of genes associated with membrane components and transmembrane transporters, enhancing the cell's capacity for substance exchange and signal transduction. Especially, when the phenol concentration was 1.6 g/L and 1.8 g/L, the degradation rates of C. tropicalis towards it were 99.47 and 95.91%, respectively. Conversely, S. cerevisiae BY4742 shows limited metabolic response, with pronounced growth inhibition and lack of phenol degradation. Therefore, our study not only sheds light on the molecular mechanisms underpinning phenol tolerance and degradation in C. tropicalis but also positions this yeast as a promising candidate for environmental and industrial processes aimed at mitigating phenol pollution. [ABSTRACT FROM AUTHOR]

AbstractIn present study, Spanish cherry pulp (SCP) was dried using refractance window (RW) dryer at varying temperatures (50 to 90 °C) to investigate the impacts on drying kinetics and physicochemical properties and compared with freeze-dried samples. An increasing RW drying temperature from 50 to 90 °C reduced drying time from 320 to 80 min. The water and oil absorption capacity showed no significant (p < 0.05) changes in RW-dried SCP samples. Noticeable changes in color values, ascorbic acid, β-carotenoid, total phenol content, total flavonoid content, and antioxidant activity were observed on increasing RW drying temperature. As per results, compared to control, RW drying at 50 °C retained most of the nutrients. From nutrient retention perspective, RW drying at 80 and 90 °C may not be suitable SCP samples. From multivariance analysis, RW drying of SCP samples can be performed at 60 °C instead of 70 °C for better nutrient contents. [ABSTRACT FROM AUTHOR]

The electrochemical oxidative phenol coupling reaction is a sustainable method for accessing biphenolic compounds. Using the dimerization of sesamol as a model reaction, insights into the reaction mechanism were gained via operando Raman spectroscopy. By varying the solvent and electrodes, different reaction mechanisms were identified and correlated with the respective product yields. [ABSTRACT FROM AUTHOR]