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The chemoselective hydrodeoxygenation of natural lignocellulosic materials plays a crucial role in converting biomass into value‐added chemicals. Yet their complex molecular structures often require multiple active sites synergy for effective activation and achieving high chemoselectivity. Herein, it is reported that a high‐entropy alloy (HEA) on high‐entropy oxide (HEO) hetero‐structured catalyst for highly active, chemoselective, and robust vanillin hydrodeoxygenation. The heterogenous HEA/HEO catalysts were prepared by thermal reduction of senary HEOs (NiZnCuFeAlZrOx), where exsolvable metals (e.g., Ni, Zn, Cu) in situ emerged and formed randomly dispersed HEA nanoparticles anchoring on the HEO matrix. This catalyst exhibits excellent catalytic performance: 100% conversion of vanillin and 95% selectivity toward high‐value 2‐methyl‐4 methoxy phenol at low temperature of 120 °C, which were attributed to the synergistic effect among HEO matrix (with abundant oxygen vacancies), anchored HEA nanoparticles (having excellent hydrogenolysis capability), and their intimate hetero‐interfaces (showing strong electron transferring effect). Therefore, our work reported the successful construction of HEA/HEO heterogeneous catalysts and their superior multifunctionality in biomass conversion, which could shed light on catalyst design for many important reactions that are complex and require multifunctional active sites. [ABSTRACT FROM AUTHOR]

To make pyrolytic bio‐oil useful as a transportation fuel, the oxygen content must be reduced, and this can be carried out by using catalytic hydrodeoxygenation (HDO) reaction. The greatest challenge is associated with the removal of strongly bound oxygenated groups without saturating the aromatic ring while preserving the number of carbons. However, the development of a stable catalyst that can selectively remove such oxygenated groups with low hydrogen consumption is still challenging. In this context, a systematic study on HDO of vanillin on bimetallic Pd−Pt catalysts was carried out. It aims to study the effect of bimetallic synergy in terms of activity and selectivity to creosol. Metallic nanoparticles of Pd and Pt were synthesized by sol immobilization technique and deposited on TiO2. The conversion of vanillin was correlated to the Pd−Pt atomic ratio, while the production of the creosol was correlated to the Pd(0)/(Pd+Pt) ratio at the surface. Full conversion of vanillin was obtained at low reaction temperature (20 °C) achieving nearly 100 % selectivity to creosol. These results represent a step forward in advancing the development of more efficient and sustainable processes for bio‐oil upgrading. [ABSTRACT FROM AUTHOR]

Vanillin is a key organoleptic component in vanilla, one of the most important natural flavors in the industry. The limited supply of natural vanilla, extracted from cured vanilla beans, elevates the commercial value of 'natural'‐labeled vanillin, producible by microbial conversion of natural precursors such as ferulic acid, eugenol, isoeugenol, lignin, and glucose. However, cellular toxicity and undesirable overoxidation of vanillin remain challenges to the microbial methods. Here, we developed a one‐pot enzymatic conversion of capsaicinoids to vanillin by retracing the biosynthetic pathway found in Capsicum plants. The enzyme cascade consists of the hydrolysis of capsaicinoids by immobilized lipase B from Candida antarctica (CALB) and the oxidative deamination of the resulting vanillylamine by ω‐transaminase from Paracoccus denitrificans (PDTA). Process optimization of individual enzyme reactions was conducted on an analytical scale, enabling>95% reaction yield of vanillin from capsaicinoids in the one‐pot cascade reaction without undesirable accumulation of the oxidation byproduct and the inhibitory reaction intermediate, i. e. vanillic acid and vanillylamine, respectively. To verify practical applicability, we performed a preparative‐scale reaction starting with 1.75 g capsaicinoids and 2.75 g sodium pyruvate at 10 mg/mL CALB and 3 μM PDTA, leading to an 81% reaction yield and a 57% isolation yield. This study is, to the best of our knowledge, the first demonstration of one‐pot production of vanillin from capsaicinoids, which might pave the way for cost‐effective and sustainable access to natural‐labeled vanillin from a renewable feedstock readily available from Capsicum fruits. [ABSTRACT FROM AUTHOR]

Vanillin is the main component of natural vanilla extract and is responsible for its flavoring properties. Besides its well‐known applications as an additive in food and cosmetics. In this, we have synthesized a new vanillin derivative. Its structure was characterized by IR, MS, NMR and confirmed by single‐crystal X‐ray analysis. The asymmetric unit of the title molecule consists of two independent half molecules, each having crystallographically imposed centrosymmetry. Reticular layers approximately parallel to the bc plane are generated from one molecule through O−H⋅⋅⋅N hydrogen bonds. The layers are linked by the second molecule through O−H⋅⋅⋅O hydrogen bonds to form a 3‐D network structure. We carried out density functional investigations to understand the compound's molecular reactivity and chemical stability. Frontier molecular orbital (FMO) analysis, global reactivity, and Fukui parameters were calculated at the B3LYP/6‐31+G(d,p) method. In 20 % to 30 % of human malignancies, RAS genes are activated ontogenetically by point mutations. New strategies to block this oncogenic protein are needed since it has proven difficult to create efficient RAS inhibitors. The above‐titled compound shows better structural activity relationship studies against Ras‐binding domine, based on this molecular docking simulation as well as the drug‐likeness analysis carried out for our newly synthesized compound. [ABSTRACT FROM AUTHOR]

In this article, we present the preparation of a novel heteroatom halogen (fluorine) and nonmetal phosphorus-doped layered graphitic carbon nitride, via the thermal decomposition technique, and examined its electrochemical monitoring ability for vanillin detection. The materials' basic properties have been observed with various analytical analyses such as X-ray diffractometry, field-emission scanning electron microscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. The proposed electrochemical sensor material was examined under various operating conditions to demonstrate a good current response for vanillin sensing. The sensor has a wide linear range (0.2–100 μM) and a lower limit of detection (LoD = 15 nM) with an enhanced sensitivity of 1.80 μA μM–1 cm–2. Ultimately, the potential utility of the suggested sensor was effectively tested on food samples, demonstrating exceptional recoveries of 99.46 and 96.76% for coffee and vanilla ice cream, respectively, with corresponding relative standard deviations of 1.83 and 1.21 for each. [ABSTRACT FROM AUTHOR]

Antioxidant vanillin (4-hydroxy-3-methoxybenzaldehyde) is used as a flavoring in foods, beverages, and pharmaceuticals. Vanillin possesses various biological effects, such as antioxidant, anti-inflammatory, antibacterial, and anticancer properties. This study aimed to investigate the biological activities of vanillin purified from Adenophora triphylla var. japonica Hara on bone-forming processes. Vanillin treatment induced mineralization as a marker for mature osteoblasts, after stimulating alkaline phosphatase (ALP) staining and activity. The bone-forming processes of vanillin are mainly mediated by the upregulation of the bone morphogenetic protein 2 (BMP2), phospho-Smad1/5/8, and runt-related transcription factor 2 (RUNX2) pathway during the differentiation of osteogenic cells. Moreover, vanillin promoted osteoblast-mediated bone-forming phenotypes by inducing migration and F-actin polymerization. Furthermore, we validated that vanillin-mediated bone-forming processes were attenuated by noggin and DKK1. Finally, we demonstrated that vanillin-mediated antioxidant effects prevent the death of osteoblasts during bone-forming processes. Overall, vanillin has bone-forming properties through the BMP2-mediated biological mechanism, indicating it as a bone-protective compound for bone health and bone diseases such as periodontitis and osteoporosis. [ABSTRACT FROM AUTHOR]

In this study, we synthesized magnetic MnFe2O4/ZIF‐67 composite catalysts using a straightforward method, yielding catalysts that exhibited outstanding performance in catalyzing the ozonation of vanillin. This exceptional catalytic efficiency arose from the synergistic interplay between MnFe2O4 and ZIF‐67. Comprehensive characterization via x‐ray photoelectron spectroscopy (XPS), x‐ray diffraction (XRD), Fourier transform infrared spectrometer (FT‐IR), Brunauer–Emmett–Teller (BET), field emission scanning electron microscopy (FE‐SEM), and energy dispersive spectroscopy (EDS) confirmed that the incorporation of MnFe2O4 promoted the creation of oxygen vacancies, resulting in an increased presence of l adsorbed oxygen (Oads) and the generation of additional ·OH groups on the catalyst surface. Utilizing ZIF‐67 as the carrier markedly enhanced the specific surface area of the catalyst, augmenting the exposure of active sites, thus improving the degradation efficiency and reducing the energy consumption. The effects of different experimental parameters (catalyst type, initial vanillin concentration, ozone dosage, initial pH value, and catalyst dosage) were also investigated, and the optimal experimental parameters (300 mg/L1.0‐MnFe2O4/ZIF‐67, vanillin concentration = 250 mg/L, O3 concentration = 12 mg/min, pH = 7) were obtained. The vanillin removal efficiency of MnFe2O4/ZIF‐67 was increased from 74.95% to 99.54% after 30 min of reaction, and the magnetic separation of MnFe2O4/ZIF‐67 was easy to be recycled and stable, and the vanillin removal efficiency of MnFe2O4/ZIF‐67 was only decreased by about 8.92% after 5 cycles. Additionally, we delved into the synergistic effects and catalytic mechanism of the catalysts through kinetic fitting, reactive oxygen quenching experiments, and electron transfer analysis. This multifaceted approach provides a comprehensive understanding of the enhanced ozonation process catalyzed by MnFe2O4/ZIF‐67 composite catalysts, shedding light on their potential applications in advanced oxidation processes. Practitioner Points: A stable and recyclable magnetic composite MnFe2O4/ZIF‐67 catalyst was synthesized through a simple method.The synergistic effect and catalytic mechanism of the MnFe2O4/ZIF‐67 catalyst were comprehensively analyzed and discussed.A kinetic model for the catalytic ozone oxidation of vanillin was introduced, providing valuable insights into the reaction dynamics. [ABSTRACT FROM AUTHOR]

This study investigated the antidiabetic effect of vanillin using in vitro, in silico, and in vivo experimental models. Type 2 diabetes (T2D) was induced in male Sprague-Dawley (SD) rats using fructose–streptozotocin (STZ), then orally administered low (150 mg/kg bodyweight) or high (300 mg/kg bodyweight) dose of vanillin for 5 weeks intervention period. Vanillin suppressed the levels of blood glucose, serum cholesterol, triglyceride, low-density lipoprotein cholesterol (LDL-c), alanine transaminase (ALT), aspartate transaminase (AST), creatinine, urea, uric acid, when elevated serum insulin, HDL-cholesterol, and concomitantly improved pancreatic β-cell function, glucose tolerance, and pancreatic morphology. It also elevated both serum and pancreatic tissue GSH level, SOD and catalase activities, and hepatic glycogen level, while depleting malondialdehyde level, α-amylase, lipase, acetylcholinesterase, ATPase, ENTPDase and 5′-nucleotidase, glucose-6-phosphatase, fructose-1,6-bisphosphatase, and glycogen phosphorylase activities. The results indicate the potent antidiabetic effect of vanillin against T2D and its associated complications. [ABSTRACT FROM AUTHOR]

Sulfonic acid-supported vanillin/bis indolylmethane-functionalized Fe3O4@SiO2-Propyl NPs were prepared and characterized by FT-IR, XRD, FE-SEM, TEM, VSM, EDX, DLS, and TGA-DTG. The catalytic efficiency of the prepared nanoparticles was subsequently investigated for the effective synthesis of imidazoquinazolines via the one-pot condensation of 2-aminobenzimidazole, aryl aldehydes, and cyclohexanone or dimedone under solvent-free condition. Some thiazoquinazolines also were prepared via the multicomponent reaction of aldehydes, dimedone, and 2-aminobenzothiazol under solvent-free condition,. This avenue is really suitable because it makes a high yield of product, doesn't take too long, doesn't need harmful materials and solvents, its work-up is easy and the catalyst is reusable. [ABSTRACT FROM AUTHOR]

Lignin is one of the most abundant bio‐aromatic molecular resources, but it is currently underutilized for energy production in the pulp and paper industry. Unlocking the full potential of lignin could have a significant impact on reducing environmental pollution, increasing the use of renewable resources, and achieving environmentally beneficial economic growth. However, effective lignin valorization requires viable and integrated reaction and separation processes to produce high value monomeric phenolics, such as vanillin and syringaldehyde. The aim of this short review is to summarize the studies on different separation methods of lignin derivatives obtained from black liquor, including extraction, membrane filtration, chromatographic separation, and the combination technologies. [ABSTRACT FROM AUTHOR]

Vanillin, a highly regarded flavor compound, has earned widespread recognition for its natural and aromatic qualities, piquing substantial interest in the scientific community. This comprehensive review delves deeply into the intricate world of vanillin synthesis, encompassing a wide spectrum of methodologies, including enzymatic, microbial, and immobilized systems. This investigation provides a thorough analysis of the precursors of vanillin and also offers a comprehensive overview of its transformation through these diverse processes, making it an invaluable resource for researchers and enthusiasts alike. The elucidation of different substrates such as ferulic acid, eugenol, veratraldehyde, vanillic acid, glucovanillin, and C6–C3 phenylpropanoids adds a layer of depth and insight to the understanding of vanillin synthesis. Moreover, this comprehensive review explores the multifaceted applications of vanillin within the food industry. While commonly known as a flavoring agent, vanillin transcends this role by finding extensive use in food preservation and food packaging. The review meticulously examines the remarkable preservative properties of vanillin, providing a profound understanding of its crucial role in the culinary and food science sectors, thus making it an indispensable reference for professionals and researchers in these domains. [ABSTRACT FROM AUTHOR]

ABSTRACT Quorum sensing (QS) is a cell-cell signaling system that enables bacteria to coordinate population density-dependent changes in behavior. This chemical communication pathway is mediated by diffusible N-acyl L-homoserine lactone signals and cytoplasmic signal-responsive LuxR-type receptors in Gram-negative bacteria. As many common pathogenic bacteria use QS to regulate virulence, there is significant interest in disrupting QS as a potential therapeutic strategy. Prior studies have implicated the natural products salicylic acid, cinnamaldehyde, and other related benzaldehyde derivatives as inhibitors of QS in the opportunistic pathogen Pseudomonas aeruginosa, yet we lack an understanding of the mechanisms by which these compounds function. Herein, we evaluate the activity of a set of benzaldehyde derivatives using heterologous reporters of the P. aeruginosa LasR and RhlR QS signal receptors. We find that most tested benzaldehyde derivatives can antagonize LasR or RhlR reporter activation at micromolar concentrations, although certain molecules also cause mild growth defects and nonspecific reporter antagonism. Notably, several compounds showed promising RhlR or LasR-specific inhibitory activities over a range of concentrations below that causing toxicity. ortho-Vanillin, a previously untested compound, was the most promising within this set. Competition experiments against the native ligands for LasR and RhlR revealed that ortho-vanillin can interact competitively with RhlR but not with LasR. Overall, these studies expand our understanding of benzaldehyde activities in the LasR and RhlR receptors and reveal potentially promising effects of ortho-vanillin as a small molecule QS modulator against RhlR.IMPORTANCEQuorum sensing (QS) regulates many aspects of bacterial pathogenesis and has attracted much interest as a target for anti-virulence therapies over the past 30 years, for example, antagonists of the LasR and RhlR QS receptors in Pseudomonas aeruginosa. Potent and selective QS inhibitors remain relatively scarce. However, natural products have provided a bounty of chemical scaffolds with anti-QS activities, but their molecular mechanisms are poorly characterized. The current study serves to fill this void by examining the activity of an important and wide-spread class of natural product QS modulators, benzaldehydes, and related derivatives, in LasR and RhlR. We demonstrate that ortho-vanillin can act as a competitive inhibitor of RhlR, a receptor that has emerged and may supplant LasR in certain settings as a target for P. aeruginosa QS control. The results and insights provided herein will advance the design of chemical tools to study QS with improved activities and selectivities.

Background: Sol-Gel is the conventional approach for in-situ formulation having several limitations, including instability, stringent storage conditions, dose inaccuracy, inconsistent drug release, and patient inconvenience. Objectives: The aim of the present investigation was to design and characterize an intelligent oro-solid in-situ targeted dosage form of Famotidine (FTD) incorporating the cross-linked chitosan-vanillin (CrL-CSV) which instantly converted into a gel upon contact with acidic media. Material and Methods: CrL-CSV was designed using microwave-assisted method inculcating FTD and vanillin (VNL). Interaction was observed using FTIR and DSC. QbD was applied to develop intelligent formulation. Taguchi design was accomplished to screen significant critical material attributes (CMAs) and process parameters (CPPs). Box-Behnken design (BBD) was used to correlate the CMAs/CPPs: the amount of CS, VNL, microwave time, and critical quality attributes (CQAs): % FTD release, mucoadhesive strength, and viscosity. CrL-CSV were evaluated using various in-vitro, ex-vivo characterization and stability. Results and Discussion: FTIR and DSC revealed no interaction between the FTD and excipients. The amount of CS, VNL, and microwave time were screened as significant variables due to the high S/N ratio and delta value from the Taguchi design. A significant effect of CMA/CPP on the CQAs was observed in BBD. The optimum CrL-CSV was designed accomplishing 8.74 % chitosan (CS), 0.94 % VNL exposing 80sec in microwave. Immediate gelling (

This study focused on the effect of a typical phenolic inhibitor, vanillin, on the growth and ethanol production of Starmerella bacillaris R5, as well as the effect of varying levels of glucose on its growth and fermentation performance. The results indicated that when the vanillin concentration was fixed at 3 g/L, increasing glucose concentration in the medium from 2% to 6% shorten the lag phage by 25.92%, increased the specific growth rate by 82.1%, and the ethanol conversion rate by 17.88%. Further analysis showed that increased glucose concentration resulted in an increase in the proportion of cells containing reactive oxygen species (ROS), a decrease in membrane permeability, and a reduction in intracellular H2O2 content. In addition, the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) increased by 58%, 35.5%, and 2.3 times, respectively. Intracellular glycerol content increased by 1.82 times. The activity of pyruvate kinase (PK), related to glucose metabolism, decreased by 54.5%, and the activity of hexokinase (HK) and 6-phosphate glucose dehydrogenase (6-PGDH) increased by 4.16 and 11.8 times, respectively. The content of reduced nicotinamide adenine dinucleotide phosphate (NADPH) increased by 19.4%. The gene expression levels of hexokinase (HK), 6-phosphate fructose kinase (PFK), isocitrate dehydrogenase (IDH3), 6-phosphate glucose dehydrogenase (PGD), ethanol dehydrogenase (ADH5), pyruvate decarboxylase (PDC) and glycerol dehydrogenase 1 (GCY1) were up-regulated by 4.6, 2.5, 13.9, 12.2, 17.5, 34.8, and 34.9 times, respectively. In summary, increasing glucose concentration increased the activity of intracellular antioxidant enzymes, attenuated oxidative damage, and provided more adenosine triphosphate (ATP) and reducing powder to cope with environmental stress, thereby increasing the conversion rate of ethanol. The results of this study could provide new ideas for utilizing S. bacillaris for bioethanol production.

Abstract The electrochemical conversion of biobased intermediates offers an attractive and sustainable process for the production of green chemicals. One promising synthesis route is the production of the total vanillin-based polymer polyvanillin, which can be produced by electrochemical pinacolization of divanillin (5–5´bisvanillyl). Divanillin can be easily enzymatically generated from vanillin, a renewable intermediate accessible from lignin on an industrial scale. This study investigates systematically the electrochemical production of polyvanillin in a divided plane parallel flow reactor in recirculation mode. Several analytic methods, such as online UV–VIS spectroscopy, size exclusion chromatography (SEC), 2D-NMR (HSQC, 13C/1H), TGA and DSC were used to monitor the reaction progress and to characterize the reaction products under different galvanostatic reaction conditions revealing new insights into the reaction mechanism and structural features of the polymer. Further, by using an electrochemical engineering-based approach determining the limiting current densities, we readily achieved high current densities over 50 mA cm−2 for the polyvanillin synthesis and reached averaged molecular weights up to Mw = 4100 g mol−1 and Mn = 2700 g mol−1. The cathodic polymerization to polyvanillin offers an innovative approach for the electrochemical production of biobased polymers presented on flow cell level. Graphical Abstract

In order to improve the stability of vanillin by polysaccharide-protein interaction and to investigate the inhibitory effect of the composite nanocarrier on Listeria monocytogenes and E. coli, a vanillin-loaded composite nanocarrier of corn bran arabinoxylan (AX) and zein was prepared. Two crude polysaccharide fractions of corn bran were obtained by precipitating with 80% and 90% ethanol. Four fractions (F80-1, F80-2, F90-1, and F90-2) were subjected to anion-exchange chromatography purification. The monosaccharide composition of the fractions was determined using gas chromatography. It was found that the total content of arabinose and xylose in each fraction was 67.41%, 76.12%, 77.16%, and 84.89%, respectively, and the encapsulation rate of vanillin in the composite nanoparticles of the four fractions was 81.18%, 69.36%, 86.80%, and 88.48%, respectively. The vanillin encapsulation and the intermolecular interaction in the composite nanocarriers were verified by fluorescence spectrometry and differential scanning calorimetry (DSC). Bacterial inhibition experiments showed that F80-2 composite nanocarriers were most effective at inhibiting Listeria monocytogenes, and F90-2 composite nanocarriers were most effective at inhibiting E. coli.

Abstract Background Vanillin represents one of the most widely used flavoring agents in the world. However, microbial synthesis of vanillin is hindered by the host native metabolism that could rapidly degrade vanillin to the byproducts. Results Here, we report that the industrial workhorse Saccharomyces cerevisiae was engineered by systematic deletion of oxidoreductases to improve the vanillin accumulation. Subsequently, we harnessed the minimal aromatic aldehyde reduction (MARE) yeast platform for de novo synthesis of vanillin from glucose. We investigated multiple coenzyme-A free pathways to improve vanillin production in yeast. The vanillin productivity in yeast was enhanced by multidimensional engineering to optimize the supply of cofactors (NADPH and S-adenosylmethionine) together with metabolic reconfiguration of yeast central metabolism. The final yeast strain with overall 24 genetic modifications produced 365.55 ± 7.42 mg l−1 vanillin in shake-flasks, which represents the best reported vanillin titer from glucose in yeast. Conclusions The success of vanillin overproduction in budding yeast showcases the great potential of synthetic biology for the creation of suitable biocatalysts to meet the requirement in industry. Our work lays a foundation for the future implementation of microbial production of aromatic aldehydes in budding yeast. Graphical Abstract

Vanillin (4-hydroxy-3-methoxybenzaldehyde) is an important platform chemical compound that is invariably produced from pyrolysis of various categories of biomass. Hydrodeoxygenation (HDO) of vanillin has been a thematic topic in catalysis with the underlying aim to devise processes and reactions for catalytic upgrading of bio-oil and in the production of value-added products. Herein, we investigate the HDO of an evaporated stream of vanillin over a 4 % load of palladium supported on ceria; a Pd/CeO2 catalyst. The synthesized catalyst was characterized by various techniques including XRD, XPS, EDX-SEM, HR-TEM, and TPR. The HDO reaction (carried out at temperatures from 100 °C to 300 °C at 10 °C/min ramp rate with a 5 % H2 feed ratio) resulted in a 95 % conversion of vanillin with an 85 % yield of guaiacol (2-methoxyphenol). Minute loads of alkylbenzene compounds (mainly xylene and ethylbenzene) also emerged. DFT computations elucidate pathways for the observed formation of guaiacol where synergistic effects of both Pd and vacant oxygen sites are highlighted. Overall, we presented a viable HDO route for an oxygenated biomass model compound at mild operational conditions (intermediate temperatures, ambient pressure, and moderate H2/Feed ratio).

Fusarium graminearum (F. graminearum) is a severe pathogen threatening the safety of agriculture and food. This study aimed to explore the antifungal efficacies of several plant-derived natural compounds (vanillin and its derivatives) against the growth of F. graminearum and investigate the antifungal mechanism of 2-hydroxy-4-methoxybenzaldehyde (HMB), the strongest one. The minimum inhibitory concentration (MIC) of HMB in inhibiting mycelial growth was 200 µg/mL. HMB at MIC damaged cell membranes by increasing the permeability by about 6-fold (p < 0.05) as evidenced by propidium iodide (PI) staining. Meanwhile, the content of malondialdehyde (MDA) and glycerol was increased by 45.91 and 576.19% by HMB treatment at MIC, respectively, indicating that lipid oxidation and osmotic stress occurred in the cell membrane. Furthermore, HMB exerted a strong antitoxigenic role as the content of deoxynivalenol (DON) was remarkably reduced by 93.59% at MIC on 7th day. At last, the antifungal effect of HMB against F. graminearum was also confirmed on wheat grains. These results not only revealed the antifungal mechanism of HMB but also suggested that HMB could be applied as a promising antifungal agent in the preservation of agricultural products. [ABSTRACT FROM AUTHOR]

Bio‐based polymer building blocks derived from abundant biomass represent a promising class of monomers for the synthesis of sustainable high‐performance polymers. Lignin‐derived vanillin is used as a bio‐based, aromatic molecular platform for chemical modifications. The use of vanillin aldehyde derivatives as monomers with different alkyl chain length, cured with bio‐based and less‐toxic di‐ and triamines, leads to covalent adaptable Schiff base networks and thus enables sustainable and thermally reprocessable high‐performance materials without using highly toxic amines. A process is presented to prepare homogeneous films of crosslinked materials that are thermally reprocessable while maintaining their mechanical performance. The network structures, mechanical properties, and thermal stability of the obtained polymeric sheets are characterized in detail. By systematically adjusting the composition of the network building blocks, the mechanical properties could be varied from tough materials with a high elastic modulus of 1.6 GPa to materials with high flexibility and elastomeric behavior with an elongation at break of 400%. Furthermore, the stress–relaxation behavior of stoichiometric and nonstoichiometric Schiff base vitrimers is investigated. The combination of bio‐based building blocks and the degradability of Schiff base networks under acidic conditions resulted in sustainable, environmentally friendly, chemically and thermomechanically recyclable vitrimers with self‐healing and shape‐memory properties. [ABSTRACT FROM AUTHOR]

A method was developed and validated for vanillin, ethyl vanillin, and methyl vanillin determination in Thai rice cultivars by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLCMS/MS) under the selected reaction monitoring mode. In rice samples, the limit of detection was 13.3, 11.2 and 5.0 μg/kg for vanillin, ethyl vanillin, and methyl vanillin. A high correlation coefficient was obtained (R² = 0.9999, 0.9999 and 0.9998) within the linear range (0 - 300 μg/L) in the MS method. The recoveries ranging from 90.63 % ± 6.25 to 108.7 % ± 2.35 were obtained in different spiking concentrations. The average RSD% of intra-day for vanillin, ethyl vanillin, and methyl vanillin was 6.90, 5.13 and 2.16 %, and the inter-day were 6.72, 5.30 and 5.64 %, respectively. The developed method was applied to 24 commercial rice samples. Vanillin, were found in 24 samples ranging from 95.2 to 773.2 μg/kg. However, ethyl vanillin and methyl vanillin were not detected under LOD. The developed UPLC-MS/MS method for vanillin, ethyl vanillin and methyl vanillin determination include the merits of simple preparation steps and high sensitivity. [ABSTRACT FROM AUTHOR]

Organic solvents are extensively used in in vitro drug metabolism studies to overcome the solubility issues of lipophilic substrate/new chemical entities. The effects of ten common water miscible organic solvents on cytochrome P450s and non-cytochrome P450 enzymes, namely, flavin monooxygense, aldehyde oxidase, xanthine oxidase, esterases and glutathione S-transferases were evaluated. Rat liver microsomes and rat liver cytosol were used for cytochrome P450, flavin monooxygenase and glutathione S-transferase assays. Partially purified guinea pig liver aldehyde oxidase and rat liver xanthine oxidase fractions were used for molybdenum hydroxylase activity assays. Human plasma was used for esterase activity. Para-nitro phenol, metoprolol, imipramine, methyl para-tolyl sulfide, para-nitrophenyl acetate, vanillin, xanthine and chloro dinitrobenzene, were used as substrates for evaluating CYP2E1, CYP2D6, CYP1A2, flavin monooxyenase, esterase, aldehyde oxidase, xanthine oxidase and glutathione S-transferase activities, respectively. Ten solvents (acetonitrile, acetone, dioxane, dimethyl formamide, dimethyl sulfoxide, ethanol, methanol, polyethylene glycol 400, n-propanol, and isopropanol) were evaluated at four concentrations (0.1, 0.25, 0.5 and 1 % v/v). The following results were obtained. Dioxane (1 % v/v) was found to a potent inhibitor inhibiting all the tested CYP's (>90 % inhibition) and flavin monooxygenase (71 % inhibition). Seven of ten organic solvents inhibited esterases in a concentration dependent manner out of which n-propanol showed the maximal inhibition (79 % inhibition). Methanol was the only solvent that inhibited aldehyde oxidase (78 % inhibition) and xanthine oxidase mediated metabolism (64 % inhibition). Minimal inhibition effect was observed on glutathione S-transferase mediated activity by all solvents. Polyethylene glycol 400 showed least inhibition of enzyme activities. Among the 10 solvents studies, acetonitrile overall appears to be the safest organic solvent at concentrations of 1 % v/v or less. The results of this study indicate that many water miscible organic solvents must be used very judiciously in drug metabolism studies. [ABSTRACT FROM AUTHOR]

Flavour is a key driver of consumer preferences and acceptability of foods, and the food industry has made food aroma compounds a crucial area of research. At present, about 80% of food aroma compounds are produced by chemical synthesis; however, alternative production approaches have been explored to meet consumers’ demand for “clean label” food products and “natural” aromas. Bio-production of food aroma compounds from vegetable wastes through fermentation has emerged as a promising alternative. This review showed that fungi and yeasts, and also lactic acid bacteria, can be used to produce aroma compounds through the fermentation of vegetable waste. The produced compounds were mostly responsible for sweet, fruity, and floral notes. Other molecules imparting cheesy/buttery, creamy, green, herbal, grass notes were also obtained through the fermentation of vegetable food waste. Substrates varied from agricultural waste such as rice bran to by-products and waste from the fruit supply chain, in particular pomace, peels, pods. During the study, challenges and limitations for the scale-up of the process emerged. The production of aromas is still strongly strain and waste dependent. Certain aspects thus still require attention to avoid that a joint occurrence of technical challenges may cause the failure of the process. [ABSTRACT FROM AUTHOR]

Maize bran, an agro‐processing waste residue, is a good source of ferulic acid that can be further valorized for vanillin production. However, extraction of ferulic acid from natural sources has been challenging due to low concentrations and intensive extraction procedures. In the present work, ferulic acid streams (purities ranging from 5% to 75%) extracted from maize bran using thermochemical methods were evaluated for biotransformation to vanillin, employing Amycolatopsis sp. as a whole‐cell biocatalyst. Initial adaptation studies were critical in improving ferulic acid assimilation and its conversion to vanillin by 65% and 56%, respectively by the fourth adaptation cycle. The effect of cell's physiological states and vanillic acid supplementation on vanillin production was studied using standard ferulic acid as a substrate in an effort to achieve further improvement in vanillin yield. In the presence of vanillic acid, 18 h cultured cells using 2 g/L of standard and isolated ferulic acid produced vanillin concentrations of up to 0.71 and 0.48 g/L, respectively. Furthermore, intermediates involved in the ferulic acid catabolic pathway and their interrelations were studied using GC–MS analysis. Results indicated that two different routes were involved in the catabolism of standard ferulic acid, and similar metabolic routes were observed for an isolated ferulic acid stream. These findings effectively evaluated isolated ferulic acid for sustainable vanillin production while reducing agro‐industrial waste pollution. [ABSTRACT FROM AUTHOR]

A dinuclear nickel compound that features vanillin (van) and acetate (OAc) bridging ligands, [Ni2(μ-van)2(μ-OAc)(NCS)3(H2O)]·5H2O 1, was synthesized and characterized using various techniques. Crystal structure analysis revealed a pair of Ni(II) ions bridged by an acetate anion through a μ2-η1:η1 coordination mode. At the same time, vanillin bridges both nickel(II) centers through phenolic oxygen, separating the two Ni ions by a distance of 3.001(7) Å. The temperature-dependent magnetism indicates weak antiferromagnetic behaviour in compound 1, following the Curie–Weiss law with Curie constant C = 1.0145 cm3 K mol−1 and Weiss constant = −4.1 K. Compound 1 was evaluated for its ability to mimic the catechol oxidase enzyme using 3,5-di-tert-butylcatechol as a model substrate with a Kcat value of 157.1 × 102 h−1. Furthermore, compound 1 was tested for its cytotoxicity against HepG2 cancer cells and DNA cleavage properties. [ABSTRACT FROM AUTHOR]

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Lignin, a major component of plant biomass, is a promising sustainable alternative carbon‐based feedstock to petroleum as a source of valuable aromatic compounds such as vanillin. However, lignin upgrading reactions are poorly understood due to its complex and variable molecular structure. This work focuses on electrocatalytic lignin upgrading, which is efficient and sustainable at moderate temperatures and pressures and does not require stoichiometric reagents. We used a meta‐analysis of published lignin conversion and product yield data to define the operating range, to select the catalyst, and then performed electrocatalytic experiments. We quantified the impact of temperature and electrical potential on the formation rate of valuable products (vanillic acid, acetovanillone, guaiacol, vanillin, and syringaldehyde). We found that increasing temperature increases their formation rate by an order of magnitude more than increasing electrical potential. For example, increasing temperature from 21 to 180 °C increases the vanillin formation rate by +16.5 mg⋅L−1⋅h−1 ±1.7 mg⋅L−1⋅h−1, while increasing electrical potential from 0 to 2 V increases the vanillin formation rate by −0.6 mg⋅L−1⋅h−1 ±1.4 mg⋅L−1⋅h−1. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The electrochemical conversion of biobased intermediates offers an attractive and sustainable process for the production of green chemicals. One promising synthesis route is the production of the total vanillin-based polymer polyvanillin, which can be produced by electrochemical pinacolization of divanillin (5–5´bisvanillyl). Divanillin can be easily enzymatically generated from vanillin, a renewable intermediate accessible from lignin on an industrial scale. This study investigates systematically the electrochemical production of polyvanillin in a divided plane parallel flow reactor in recirculation mode. Several analytic methods, such as online UV–VIS spectroscopy, size exclusion chromatography (SEC), 2D-NMR (HSQC, 13C/1H), TGA and DSC were used to monitor the reaction progress and to characterize the reaction products under different galvanostatic reaction conditions revealing new insights into the reaction mechanism and structural features of the polymer. Further, by using an electrochemical engineering-based approach determining the limiting current densities, we readily achieved high current densities over 50 mA cm−2 for the polyvanillin synthesis and reached averaged molecular weights up to Mw = 4100 g mol−1 and Mn = 2700 g mol−1. The cathodic polymerization to polyvanillin offers an innovative approach for the electrochemical production of biobased polymers presented on flow cell level. [ABSTRACT FROM AUTHOR]

Biomass appears to be a potential candidate for the preparation of porous carbon materials with wide applications for catalytic fields due to its low price, green sustainability and natural hierarchical porous structure. Here, we designed a novel NixCuy/BC catalyst with a unique hollow sphere structure derived from a biomass puffball, which exhibited a superior catalytic transfer hydrodeoxygenation of VAN to value-added MMP products with an ∼100% vanillin (VAN) conversion and over 88% selectivity of 2-methoxy-4-methylphenol (MMP) products in the absence of additional hydrogen. The good catalytic activity performance of the NixCuy/BC catalysts was attributed to the NiCu alloy with a unique hollow sphere structure, high dispersion and electron transfer. Density functional theory (DFT) calculation results also indicated NiCu alloy as the main catalytic sites. This work not only provided a cheap and efficient hydrodeoxygenation catalyst for VAN hydrodeoxygenation, but also offered new insights for designing novel and unique biomass-based carbon materials for biomass utilizations or other widespread applications. [ABSTRACT FROM AUTHOR]

The flavoring agent natural vanilla contains an abundant amount of the 4-hydroxy-3-methoxybenzaldehyde (Vanillin) biophenol compound. It is imperative to construct affordable and cost-effective approaches for determining the quantitative composition of Vanillin. In this work, we demonstrate a selective and sensitive electrochemical sensor for the detection of Vanillin by CaMoO4/P-CNT/GCE. We characterized our prepared nanomaterial using field emission scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, Raman spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The electrochemical performance and analytical capabilities of this electrochemical sensor were evaluated using cyclic voltammetry, differential pulse voltammetry, and amperometry techniques. As a result of the nanocomposite, high conductivity, and high active surface area, the proposed electrochemical sensor has excellent sensitivity (DPV: 1.9718 and amperometry: 1.0947 μA μM–1 cm–2), low detection limit (DPV: 0.0017 and it amperometry: 0.00084 μM), high selectivity, and well reproducibility toward detection of Vanillin. In addition, real-sample analysis confirmed the high performance of the sensor developed in the present study. [ABSTRACT FROM AUTHOR]

This study aimed to design a new Benzydamine HCl (BNZ) suppo-sponge for controlled, mucoadhesive dosage form for vaginal candidiasis treatment, offering advantages over traditional creams, ointments, or gels. BNZ-loaded suppo-sponges were fabricated by simple casting / freeze-drying technique utilizing the cross-linking of chitosan (Cs) with vanillin (V). Vaginal suppo-sponges were prepared based on different vanillin cross-linking ratios (V).n), from 0 to 2%w/w. To best of our knowledge, this is the first study that uses Schiff's base between chitosan and vanillin as a drug delivery system to treat fungal vaginal infections. Schiff's base formation was confirmed by FT-IR. In-vitro appraisal showed acceptable physical and mechanical characteristics. Formulations based on cross-linking of Cs with V showed a more pronounced in-vitro antifungal activity. In-vitro drug release revealed a prolonged release pattern, becoming more noticeable with the higher cross-linked suppo-sponges (22.34% after 8 h). In-vivo testing of CsV2 suppo-sponge indicated a more pronounced reduction in fungal count than both CsV0 and Tantum® Rosa in the first week, with a peak reduction on day 7 and the 10th and 11th days of the second week. Conclusively, Chitosan/vanillin suppo-sponges represent a promising delivery system for drugs intended for local treatment of vaginal candidiasis. than both CsV0 and Tantum® Rosa in the first week, with a peak reduction on day 7 and the 10th and 11th days of the second week. Conclusively, Chitosan/vanillin suppo-sponges represent a promising delivery system for drugs intended for local treatment of vaginal candidiasis. [ABSTRACT FROM AUTHOR]

Urea levels in urine play an important parameter in diagnosing bodily conditions through liver and kidney examinations. The typical reagent for detecting urea content in urine is para-dimethylaminobenzaldehyde (pDMAB). However, it has a drawback related to the instability of color in the resulting Schiff base compound (pDMAB-urea). In this study, the synthesized vanillin compound derived from clove oil serves as the foundational material for a urea chemosensor based on the colorimetric concept. The synthesized vanillin was characterized using FTIR, GCMS, and 1H-NMR. The formulation of the vanillin compound as a sensor was conducted by assessing the suitable solvent, determining the optimal mass of vanillin, and evaluating the acid-base conditions of the sensor formulation system both qualitatively and quantitatively. Subsequently, the most effective formulation was selected for detecting urea in urine samples. The synthesis of vanillin yielded a purity level of 95%. The optimal formulation was obtained at an optimum mass of vanilla of 0.75 g in 50 mL of 96% ethanol and 10 mL of 10% NaOH. The color change in the sample was from colorless to greenish yellow (436 nm). The vanillin obtained was applied to urine samples with the best results at a sample dilution level of 10,000×. [ABSTRACT FROM AUTHOR]

Vanillin is a flavouring agent that is prohibited for use in infant food products with ages lower than 6 months. Excessive vanillin usage could lead to eating disorders, nausea, headache, and vomiting. Therefore, it is essential to control the contents of vanillin in food samples, especially in infant formula. Here, we developed a highly sensitive nanosensor for vanillin based on using green synthesized highly fluorescent (QY = 29.5%) N‐doped carbon quantum dots (N‐CQDs) as a turn‐off fluorescent nanoprobe. The N‐doped CQDs synthesis was adopted using citrus bulb squeeze extract and the commonly used fertilizer, urea, as substrates. After mixing with vanillin, the fluorescence of the N‐CQDs was largely quenched in a vanillin concentration‐dependent manner. The sensing conditions were optimized by quality‐by‐design using a two‐level full factorial design (22 FFD). The N‐doped CQDs could detect vanillin in the range 0.1–12.0 μg/ml with a limit of detection of 0.013 μg/ml. Next, a smartphone imaging‐based assay combined with a UV chamber was adopted and applied for vanillin determination. This simple detection technique showed sensitivity similar to that of the conventional fluorimetric method. Both conventional and smartphone‐based methods were successfully applied for the determination of vanillin in infant milk formula and biscuits and could detect real vanillin concentrations in the analyzed samples with high % recoveries (94.5% to 105.5%). At last, the biocompatibility of the newly synthesized N‐CQDs was tested, and it was found to be an excellent candidate for cancer cell imaging. [ABSTRACT FROM AUTHOR]

The efficient utilization of all of the key lignocellulosic biomass residues is important for the development of an integrated biorefineries uassing this as its feedstock. In this study, a process involving a simultaneous pre-treatement process with anaerobic digestion (AD) were implemented for processing oil palm empty fruit bunches (OPEFB) in order to produced both vanillin and methane. Before and after treatment with the dry rot fungus (Serpula lacrymans) the biomass was analyzed for total reducing sugar (TRS), total soluble phenols (TSP), pH, and weighed. Change in the physical characteristic and morphology of untreated and OPEFB following fungal culture was observed using scanning electron microscopy (SEM). The biomethane potential (BMP) of pretreated OPEFB significantly increased (62.07%) compared to untreated sample and in addition. The amount of vanillin extracted reached 3.48ug mL−1. This study therefore confirms that multiple products can effectively be isolated using a fungal preatreatment of lignocellulosic OPEFB followed by anerobic fermentation of biomass residual thus maximizing the potential returns and reducing environmentally impacts compared to other pretreatments. [ABSTRACT FROM AUTHOR]

AbstractElectronic cigarettes (E-cigarettes) have become popular around the world. An important reason is the variety of available flavors. However, many countries have imposed restrictions on flavor substances in E-cigarettes due to their potential health risks. Therefore, it is necessary to develop an effective way to identify flavorings in E-cigarette liquids. In this work, direct analysis in real time-mass spectrometry (DART-MS) in the quick strip (QS) mode was developed and applied to determine flavorings in the E-cigarettes. Vanillin, ethyl vanillin, maltol, and ethyl maltol were quantified. Meanwhile, the ionization efficiency of flavorings in the different solvents was compared in the QS mode, which revealed that the solvent boiling point was related to the analyte ionization efficiency. The effect of endogenous matrix (propylene glycol and glycerol) on flavoring ionization was also investigated. Calibration curves with satisfactory linearity (R2 > 0.99) were established from 1 to 1000 μg L−1. Good sensitivity (limits of detection [LODs] < 0.3 μg L−1), recoveries (92.6% to 104.7%), and acceptable repeatability (relative standard deviations < 14.6%, n = 5) were obtained. The limits of quantification (LOQs; 10–50 μg g−1) for the E-cigarette liquid sample were much lower than the regulatory limits. The developed method provided a simple way for rapidly determining flavorings in E-cigarettes. [ABSTRACT FROM AUTHOR]

Vanillin, one of the most widely used and appreciated flavoring agents worldwide, is the main constituent of vanilla bean extract, obtained from the seed pods of various members belonging to the Orchidaceae family. Due to the great demand in the food confectionery industry, as well as in the perfume industry, medicine, and more, the majority of vanillin used today is produced synthetically, and only less than one percent of the world's vanilla flavoring market comes directly from the traditional natural sources. The increasing global demand for vanillin requires alternative and overall sustainable new production methods, and the recovery from biobased polymers, like lignin, is an environmentally friendly alternative to chemical synthesis. The present review provides firstly an overview of the different types of vanillin, followed by a description of the main differences between natural and synthetic vanillin, their preparation, the market of interest, and the authentication issues and the related analytical techniques. Then, the review explores the real potentialities of lignin for vanillin production, presenting firstly the well-assessed classical methods and moving towards the most recent promising approaches through chemical, biotechnological and photocatalytic methodologies, together with the challenges and the principal issues associated with each technique. [ABSTRACT FROM AUTHOR]

Substituted benzaldehydes are the most commonly used natural-occurring flavours in the world. The consumer's preference for 'natural or organic' aromas has increased the request for flavours possessing the 'natural' status. The resulting shortage of aromatic aldehydes of extractive origin, such as vanillin, veratraldehyde and piperonal, can be offset by developing a new biotechnological synthesis method. Here, we report a study on the microbiological reduction of five natural benzoic acid derivatives, namely p-anisic, vanillic, veratric, piperonylic and eudesmic acids, to produce the corresponding fragrant aldehydes. We found that different Basidiomycota strains can efficiently perform this transformation, with good chemical selectivity and tolerance to the toxicity of substrates and products. Besides confirming the carboxylic acid reductase activity of the already studied fungi Pycnoporus cinnabarinus, we discovered that other species such as Pleurotus eryngii, Pleurotus sapidus and Laetiporus sulphureus as well as the non-ligninolytic fungi Lepista nuda are valuable microorganisms for the synthesis of anisaldehyde, vanillin, veratraldehyde, piperonal and 3,4,5-trimethoxybenzaldehyde from the corresponding acids. According to our findings, we propose a reliable process for the preparation of the above-mentioned aldehydes, in natural form. Key points: • Fragrant benzaldehydes were obtained by biotransformation. • Basidiomycota strains reduced substituted benzoic acid to the corresponding aldehydes. • Anisaldehyde, vanillin, veratraldehyde, piperonal and 3,4,5-trimethoxybenzaldehyde were prepared in natural form. [ABSTRACT FROM AUTHOR]

Herein, the electrodeposition of paracetamol oxide (PA ox) for the intelligent portable ratiometric detection of nicotine (NIC) and ethyl vanillin β- D -glucoside (EVG) is reported. PA ox electrodeposited on a screen-printed carbon electrode (SPCE) was used as a new fixed state ratiometric reference probe. A portable electrochemical workstation combined with a smart phone was applied as an intelligent portable electrochemical sensing platform. The sensor was studied by scanning electron microscopy (SEM), Fourier transform infrared spectrophotometry (FT-IR), ultraviolet-visible spectrophotometry (UV-vis), theoretical calculation, chronoamperometry, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV). Under optimized conditions, the detection range of NIC is 10–200 μmol L−1, and the detection limit is 0.256 μmol L−1. The detection range of EVG was 10–180 μmol L−1, and the detection limit was 0.058 μmol L−1. The sensor can realize the real-time detection of NIC and EVG concentration in cigarette samples quickly and accurately, and has good anti-interference, repeatability and stability. [ABSTRACT FROM AUTHOR]

Background: Vanillin represents one of the most widely used flavoring agents in the world. However, microbial synthesis of vanillin is hindered by the host native metabolism that could rapidly degrade vanillin to the byproducts. Results: Here, we report that the industrial workhorse Saccharomyces cerevisiae was engineered by systematic deletion of oxidoreductases to improve the vanillin accumulation. Subsequently, we harnessed the minimal aromatic aldehyde reduction (MARE) yeast platform for de novo synthesis of vanillin from glucose. We investigated multiple coenzyme-A free pathways to improve vanillin production in yeast. The vanillin productivity in yeast was enhanced by multidimensional engineering to optimize the supply of cofactors (NADPH and S-adenosylmethionine) together with metabolic reconfiguration of yeast central metabolism. The final yeast strain with overall 24 genetic modifications produced 365.55 ± 7.42 mg l−1 vanillin in shake-flasks, which represents the best reported vanillin titer from glucose in yeast. Conclusions: The success of vanillin overproduction in budding yeast showcases the great potential of synthetic biology for the creation of suitable biocatalysts to meet the requirement in industry. Our work lays a foundation for the future implementation of microbial production of aromatic aldehydes in budding yeast. [ABSTRACT FROM AUTHOR]

This study investigated the total phenol content, phenolic composition, and antioxidant activities of cosmetic and alimentary argan oil extracted from fruits collected from two different regions of Algeria (Mostaganem and Tindouf). The phenolic composition of the argan oil was analyzed by HPLC and quantified by colorimetric method. Antioxidant properties were studied using DPPH and β-carotene/linoleic acid system. In total, six phenolic compounds were identified, which are hydroxytyrosol, vanillic acid, tyrosol, ferulic acid, vanillin, and syringic acid. The alimentary oil from Mostaganem exhibited the highest concentration of phenolic compounds. Each of the oils showed high antioxidant activities in the two systems studied. Alimentary oils exhibited the highest antioxidant activity. The oils from Mostaganem had the highest levels of phenolic content and antioxidant activities compared to those from the region of Tindouf. The present study confirmed that argan oil exhibited a significant antioxidant potential. [ABSTRACT FROM AUTHOR]

This paper focuses on the performance of Molybdenum-vanadiumphosphorus heteropolyacids (PMo12-xVx) with different V-doped amounts in catalyzing the conversion of lignin to bio-oil, and the distribution of liquefied products. Molybdenum-vanadium-phosphorus heteropolyacids (PMo11V1, PMo10V2, PMo9V3) with different amount (0, 2.5, 5, 10 wt%) were used to catalyze lignin liquefaction. The experimental results showed that PMo12-xVx could effectively catalyze the depolymerization of lignin to bio-oil, and the doping amount of the V atom in PMo12-xVx affects the distribution of lignin depolymerization products. The highest bio-oil yield (53.62wt%) and conversion (57.83wt%) could be obtained from lignin liquefaction at 2.5 wt% PMo9V3. With the increase of PMo12-xVx V-atom doped amount, the content of aliphatic hydrocarbons increased from 3.14% to 40.58%, the content of vanillin increased from none to 8.9%. Based on the analysis of bio-oil, FT-IR data, and DFT simulation results, it was found that the selective cleavage of the Cα-Cβ bond and the ring-opening of the carbon at the methyl end of lignin were the main reasons for the high yield of vanillin and aliphatic hydrocarbons during the depolymerization of lignin catalyzed by PMo12-xVx. Finally, a possible reaction pathway for the PMo12-xVx-catalyzed depolymerization of lignin to vanillin and aliphatic hydrocarbons was proposed. [ABSTRACT FROM AUTHOR]

Preparing 2-methoxy-4-methylphenol (MMP) through the vanillin (VAN) route is a crucial step in the high-value utilization of lignin (VTM). In this study, a series of Ni/PB catalysts were synthesized using pseudoboehmite (PB) as a carrier. Changes in the valence states of Ni were induced through H2 activation, while the impacts of reaction temperature, initial pressure, and catalyst addition were investigated based on the VTM process. The results revealed that PB exhibited a distinct mesoporous structure (average pore size of 5.8 nm), with Ni loaded in small particles size (3.88 nm). Ni species on the catalyst existed in a + 2-valence state, undergoing a change after H2 activation, with an increase in Ni0 promoting enhanced activity. The Ni/PB-450 catalyst exhibited excellent activity at 250&#176C for 3 hours (VAN conversion and MMP selectivity > 99%), and the catalyst demonstrated good durability, maintaining 99.1% VAN conversion and 80% MMP selectivity after two cycles. Combining the characterization and experimental results, the etherification and hydrogenation of VAN were identified as the primary reaction pathways. This study aimed to provide a new avenue for the high-value utilization of lignin and its derivatives through controlled catalyst preparation [ABSTRACT FROM AUTHOR]