Cinnamyl Alcohol Research Articles

Differential response of phenylpropanoid pathway as linked to hormonal change in two Brassica napus cultivars contrasting drought tolerance.

Oilseed rape (Brassica napus L.) is a significant agro-economic crop with a wide range of uses. Drought is the most frequent unfavourable environmental stressor restraining its growth and development worldwide. This study was conducted to characterize the drought-responsive phenylpropanoid pathway and its link to hormonal changes in two cultivars, drought-resistant "Saturnin" and drought-susceptible "Mosa." Drought susceptibility in cv. Mosa was confirmed by its lower water use efficiency and higher lipid peroxidation levels with reactive oxygen species (ROS) accumulation. In cv. Saturnin, higher salicylic acid (SA) levels and expression of dehydration-responsive element binding 2 (DREB2) and non-expressor of pathogenesis-related gene 1 (NPR1) led to an upregulation of production of anthocyanin pigment 1 (PAP1) and phenylpropanoid pathway-related gene (CHS, F5H and COMT1) expression, increasing hydroxycinnamic acid and flavonoid compound concentrations. However, in cv. Mosa, higher increases in the activity of lignifying enzymes (polyphenol oxidase, coniferyl alcohol peroxidase, syringaldazine peroxidase, guaiacol peroxidase) and expression of the lignin synthesis-related gene cinnamyl alcohol dehydrogenase 2 (CAD2) were found along with greater increases in abscisic acid (ABA) levels and upregulation of ABA-responsive element binding 2 (AREB2) and basic helix-loop-helix transcription factor MYC2. These results indicate that drought-induced SA-mediated activation of the hydroxycinnamic acid and flavonoid pathways contributes to drought resistance, whereas ABA-mediated lignification contributes to drought susceptibility.

Citral enhances disease resistance in postharvest citrus fruit through inducing jasmonic acid pathway and accumulating phenylpropanoid compounds

Citral, a monoterpene naturally present in volatile oils of Litsea cubeba, Cymbopogon flexuosus and citrus peel, can enhance disease resistance in postharvest citrus fruit and reduce fruit decay due to Penicillium digitatum. To clarify the defense mechanism involved in the enhancement of disease resistance, RNA-seq, metabolomics and biochemical analyses were integrated to global change in citral-treated fruit. Results showed that citral fumigation was effective at controlling citrus green mold. Citral increased the activities of phenylalanine ammonia-lyase, peroxidase, and polyphenol oxidase, followed by elevated contents of total phenolics, flavonoids, and lignin. Metabolomics revealed that citral treatment triggered accumulation of the plant hormones methyl jasmonate, abscisic acid, and indoleacetic acid, and many phenylpropanoid metabolites including curcumin, cinnamyl alcohol, hesperidin, syringin, 7-methoxyflavonol, vitexin-2-O-rhamnoside, coniferin, naringin, kaempferol-7-neohesperidoside, and trans-cinnamaldehyde. RNA-seq results revealed that the expression levels of multiple genes involved in jasmonic acid (JA) profiles and phenylpropanoid biosynthesis were markedly upregulated by citral. These findings suggest that the JA pathway is positively involved in the induced disease resistance of citrus fruit by citral, and provide a novel theoretical support by which citral fumigation manages postharvest citrus green mold.

Efficient C = O bond hydrogenation of cinnamaldehyde over PtCu alloy frame: Insight into the morphology and Pt species state

Highly selective hydrogenation of cinnamaldehyde (CAL) to cinnamic alcohol (COL) remains the great challenge due to the co-existence of C = C and C = O bond in CAL. Herein, Al2O3 supported a series of wheel-like PtCux nanoframes (NFs) with varied Pt/Cu ratios were successfully fabricated, featuring unique electronic and geometric structure. Theoretical calculations and characterizations demonstrate that Cu can effectively optimize the d-band center, improve the distribution and utilization of Pt significantly. Compared with pure Pt crystal, PtCu1.21 NFs display the superior catalytic performance with high selectivity towards COL at a CAL conversion of over 99 %. The in-situ Fourier transform infrared (FTIR) spectroscopy reveals that the highly distribution and optimized d-band center of Pt could effectively weaken C = C bond interaction and strengthen the interaction of C = O bond on catalysts surface, boosting C = O bond hydrogenation to COL.

Anti-inflammatory and Analgesic Effect of 70% Cinnamon Bark (Cinnamomum burmannii Blume.) Ethanolic Extract In Vivo

Cinnamon bark is known as a medicinal plant to has anti-inflammatory and analgesic effects in vitro. This activity is due to bark of cinnamon containing several compounds including cinnamaldehyde, cinnamic alcohol, cinnamic acid and coumarin. The aim of this study was to observe anti-inflammatory and analgesic effects in vivo. Anti-inflammatory test using Winter method and rats. Rats were divided into five groups negative control (aquadest), positive control (sodium diclofenac), and three extract groups with different doses (300, 400, and 500 mg/kg BW). In an analgesic test using the Siegmund method and mice. Mice were also divided into five groups negative control (aquadest), positive control (sodium diclofenac), and three extract groups with different doses (300, 400, 500 mg/kg BW). Based on a statistical test, 70% ethanol extract of cinnamon bark has anti-inflammatory and analgesic effects, also showed that there was a significant difference between the positive controls and the three extract doses. This shows that the anti-inflammatory and analgesic activity of diclofenac sodium is better than the ethanol extract of cinnamon bark in reducing the edema volume of rats and the amount of mice stretch. In conclusion,cinnamon bark showed no significant increment in high doses of anti-inflammatory and analgesic.

MePOD12 participates the regulation to postharvest physiological deterioration by ROS scavenging and lignin accumulation in cassava tuberous roots

Cassava tuberous root, as a staple food crop and industrial raw material worldwide, is highly sensitive to postharvest physiological deterioration (PPD) caused by wound. However, the molecular mechanism underlying PPD tolerance remains elusive in cassava. The reactive oxygen species (ROS) scavenging system is activated at the preliminary stage of PPD and peroxidase (POD) can effectively eliminate ROS. The expression level of MePOD12 and POD enzymatic activity in cassava tuberous roots was considerably up-regulated with PPD occurrence. Yeast two-hybrid and luciferase reporter assay showed that MePOD12 physically interacted with lignin-related cinnamyl alcohol dehydrogenase 15 (MeCAD15) in vitro and in vivo. The MePOD12-silenced tuberous roots decayed more than control, especially stored at room temperature for 3 and 5 days after harvesting. The total antioxidant capacity, activities of POD, SOD, CAT, CAD and lignin content were lower than those of control. Particularly, after harvest for 3 days, the accumulation of hydrogen peroxide and superoxide anion substantially increased compared to control. In addition, a proposed model was generated to elaborate the response mechanism of MePOD12 participating in PPD regulation via ROS elimination and lignin accumulation. It provides a new clue for breeding cassava PPD-tolerant varieties.

Effects of Planting Density—Potassium Interaction on the Coordination among the Lignin Synthesis, Stem Lodging Resistance, and Grain Yield in Oil Flax

To clarify the effects of planting density (PD) and potassium (K) application on the lignin synthesis of oil flax stalks and their relationship with lodging resistance, a two-year field experiment was conducted in the 2020 and 2021 growing seasons. The planting densities were 600 grains·m−2 (D1), 750 grains·m−2 (D2), and 900 grains·m−2 (D3); the potassium application levels were 0 kg K·hm−2 (K0), 60 kg K·hm−2 (K1,) and 90 kg K·hm−2 (K2). Then, the effects of PD and K on the stalk agronomic traits, lignin synthesis, lodging resistance, and grain yield (GY) of oil flax were studied. The results show that D3 increased the oil flax plant height and stem fresh weight, and K1 raised the height of the center of gravity. The enzyme activities of phenylalanine aminolyase (PAL), cinnamyl alcohol dehydrogenase (CAD), and peroxidase (POD) increased with an increase in planting density, whereby K1 promoted and K2 inhibited the lignin metabolic enzymes, respectively. The lignin and cellulose were significantly positively correlated with PAL. The combination of K with the D2 treatment increased the lignin and cellulose content in stems of oil flax at the kernel and maturity stages, and the effect of K1 on lignin metabolism and lodging resistance was better than that of K2. The increased GY was significantly correlated with the number of effective oil flax capsules per plant and the lodging resistance index, which were directly affected by K application. In conclusion, under the same ecological conditions as the experiment, the field management strategy of medium PD (750 grains·m−2) and low K (60 kg K·hm−2) was the best for improving the lodging resistance and GY formation of oil flax.

THE OBTAINING RHODIOLA ROSEA L. BIOLOGICALLY ACTIVE COMPOUNDS BY BIOTECHNOLOGICAL METHODS (OVERVIEW)

Due to its rich chemical composition including unique biologically active compounds the gold root (Rhodiola rosea L.) is still of interest to researchers all over the world. However, deficiency of the raw material base and metabolome variability are determination the modern development ways of pharmacologically active substances in vitro obtaining. The article summarizes and systematizes the information about of Rhodiola rosea biologically active compounds obtaining, which are most often obtaining from callus tissues. Callus tissue is usually obtaining from leaf explants, and Murashige and Skoog medium with plant growth regulators in various combinations and concentrations is most commonly used for its induction. At the same time, the tissue growth efficiency and target compounds accumulation depends on the intact plant genotype, the precursors presence of these compounds in the medium, elicitors, as well as external influence factors. Recently, a promising direction is the transgenic hairy roots cultivation, which reveals new aspects of synthesis, accumulation and secondary metabolites production regulation. Biosynthesis genetic regulation of significant secondary metabolites is also a promising direction. Numerous studies have demonstrated that salidroside biosynthesis depends on the expression of the TyrDC gene encoding tyrosinedecarboxylase. Consequently, understanding the molecular and genetic mechanisms opens up opportunities for its regulation and metabolic engineering. In this regard, biotechnological methods may be a priority to obtaining salidroside, rosin and their derivatives at higher or at least comparable levels with wild type or cultivated plants.
 Among the various biotechnological strategies used to increase the accumulation of salidroside and glycosides of cinnamic alcohol in cells and cultures of Rhodiola organs, the approach with the addition of the metabolic precursors to the nutrient medium proved to be the most effective. In vitro cultures, a significant increase in the production of rosin and its derivatives was observed when precursors (cinnamic alcohol, cinnamic acid and cinnamic aldehyde) were added to the medium.

Hydroxycinnamaldehyde-derived benzofuran components in lignins.

Lignin is an abundant polymer in plant secondary cell walls. Prototypical lignins derive from the polymerization of monolignols (hydroxycinnamyl alcohols), mainly coniferyl and sinapyl alcohol, via combinatorial radical coupling reactions and primarily via the endwise coupling of a monomer with the phenolic end of the growing polymer. Hydroxycinnamaldehyde units have long been recognized as minor components of lignins. In plants deficient in cinnamyl alcohol dehydrogenase, the last enzyme in the monolignol biosynthesis pathway that reduces hydroxycinnamaldehydes to monolignols, chain-incorporated aldehyde unit levels are elevated. The nature and relative levels of aldehyde components in lignins can be determined from their distinct and dispersed correlations in 2D 1H-13C-correlated nuclear magnetic resonance (NMR) spectra. We recently became aware of aldehyde NMR peaks, well resolved from others, that had been overlooked. NMR of isolated low-molecular-weight oligomers from biomimetic radical coupling reactions involving coniferaldehyde revealed that the correlation peaks belonged to hydroxycinnamaldehyde-derived benzofuran moieties. Coniferaldehyde 8-5-coupling initially produces the expected phenylcoumaran structures, but the derived phenolic radicals undergo preferential disproportionation rather than radical coupling to extend the growing polymer. As a result, the hydroxycinnamaldehyde-derived phenylcoumaran units are difficult to detect in lignins, but the benzofurans are now readily observed by their distinct and dispersed correlations in the aldehyde region of NMR spectra from any lignin or monolignol dehydrogenation polymer. Hydroxycinnamaldehydes that are coupled to coniferaldehyde can be distinguished from those coupled with a generic guaiacyl end-unit. These benzofuran peaks may now be annotated and reported and their structural ramifications further studied.

Enantioselective Synthesis of Cyclobutane Derivatives via Cascade Asymmetric Allylic Etherification/[2 + 2] Photocycloaddition.

Chiral cyclobutane presents as a popular motif in natural products and biologically active molecules, and its derivatives have been extensively used as key synthons in organic synthesis. Herein, we report an efficient synthetic method toward enantioenriched cyclobutane derivatives. The reaction proceeds in a cascade fashion involving Ir-catalyzed asymmetric allylic etherification and visible-light induced [2 + 2] cycloaddition. Readily available branched allyl acetates and cinnamyl alcohols are directly used as the substrates under mild reaction conditions, providing a broad range of chiral cyclobutanes in good yields with excellent diastereo- and enantioselectivities (up to 12:1 dr, >99% ee). It is worth noting that all substrates and catalysts were simultaneously added without any separated step in this approach. The gram-scale reaction and diverse transformations of product further enhance the potential utility of this method.

Selenium-molybdenum interactions reduce chromium toxicity in Nicotiana tabacum L. by promoting chromium chelation on the cell wall

Chromium (Cr) is a hazardous heavy metal that negatively affects animals and plants. The micronutrients selenium (Se) and molybdenum (Mo) have been widely shown to alleviate heavy metal toxicity in plants. However, the molecular mechanism of Cr chelation on the cell wall by combined treatment with Se and Mo has not been reported. Therefore, this study aimed to explore the effects of Se-Mo interactions on the subcellular distribution of Cr (50 µM) and on cell wall composition, structure, functional groups and Cr content, in addition to performing a comprehensive analysis of the transcriptome. Our results showed that the cell walls of shoots and roots accumulated 51.0% and 65.0% of the Cr, respectively. Furthermore, pectin in the cell wall bound 69.5%/90.2% of the Cr in the shoots/roots. Se-Mo interactions upregulated the expression levels of related genes encoding galacturonosyltransferase (GAUT), UTP-glucose-1-phosphate uridylyltransferase (UGP), and UDP-glucose-4-epimerase (GALE), involved in polysaccharide biosynthesis, thereby increasing pectin and cellulose levels. Moreover, combined treatment with Se and Mo increased the lignin content and cell wall thickness by upregulating the expression levels of genes encoding cinnamyl alcohol dehydrogenase (CAD), peroxidase (POX) and phenylalanine amino-lyase (PAL), involved in lignin biosynthesis. Fourier-transform infrared (FTIR) spectroscopy results showed that Se + Mo treatment (in combination) increased the number of carboxylic acid groups (-COOH) groups, thereby enhancing the Cr chelation ability. The results not only elucidate the molecular mechanism of action of Se-Mo interactions in mitigating Cr toxicity but also provide new insights for phytoremediation and food safety.

Identification, Characterization, and Computer-Aided Rational Design of a Novel Thermophilic Esterase from Geobacillus subterraneus, and Application in the Synthesis of Cinnamyl Acetate.

Investigation of a novel thermophilic esterase gene from Geobacillus subterraneus DSMZ 13552 indicated a high amino acid sequence similarity of 25.9% to a reported esterase from Geobacillus sp. A strategy that integrated computer-aided rational design tools was developed to select mutation sites. Six mutants were selected from four criteria based on the simulated saturation mutation (including 19 amino acid residues) results. Of these, the mutants Q78Y and G119A were found to retain 87% and 27% activity after incubation at 70°C for 20min, compared with the 19% activity for the wild type. Subsequently, a double-point mutant (Q78Y/G119A) was obtained and identified with optimal temperature increase from 65 to 70°C and a 41.51% decrease in Km. The obtained T1/2 values of 42.2min (70°C) and 16.9min (75°C) for Q78Y/G119A showed increases of 340% and 412% compared with that in the wild type. Q78Y/G119A was then employed as a biocatalyst to synthesize cinnamyl acetate, for which the conversion rate reached 99.40% with 0.3M cinnamyl alcohol at 60°C. The results validated the enhanced enzymatic properties of the mutant and indicated better prospects for industrial application as compared to that in the wild type. This study reported a method by which an enzyme could evolve to achieve enhanced thermostability, thereby increasing its potential for industrial applications, which could also be expanded to other esterases.

Highly selective transfer hydrogenation of α,β-unsaturated aldehydes by frustrated Lewis pairs (FLPs) on oxygen-defect-rich Co3O4@NC

Herein, we propose a facile strategy to synthesize oxygen-defect-rich Co3O4@NC porous nanorods derived by in situ pyrolysis of Co-MOF@N, which proves to be frustrated Lewis pairs (FLPs). The oxygen-defect-rich Co3O4@NC with FLPs sites (unliganded Co…N) gives 93.4 % selectivity to cinnamyl alcohol at >99.0 % cinnamaldehyde conversion. Density functional theory calculations reveal that the unliganded Co…N FLP sites can effectively activate cinnamaldehyde and isopropanol and reduce the activation energy barrier, thus significantly improving the catalytic performance. The substrate-extending experiments show that Co3O4@NC presents brighter prospects in the selective transfer hydrogenation of a series of α,β-unsaturated aldehydes.

Integrative analysis of metabolome, proteome, and transcriptome for identifying genes influencing total lignin content in Populus trichocarpa.

Lignin, a component of plant cell walls, possesses significant research potential as a renewable energy source to replace carbon-based products and as a notable pollutant in papermaking processes. The monolignol biosynthetic pathway has been elucidated and it is known that not all monolignol genes influence the total lignin content. However, it remains unclear which monolignol genes are more closely related to the total lignin content and which potential genes influence the total lignin content. In this study, we present a combination of t-test, differential gene expression analysis, correlation analysis, and weighted gene co-expression network analysis to identify genes that regulate the total lignin content by utilizing multi-omics data from transgenic knockdowns of the monolignol genes that includes data related to the transcriptome, proteome, and total lignin content. Firstly, it was discovered that enzymes from the PtrPAL, Ptr4CL, PtrC3H, and PtrC4H gene families are more strongly correlated with the total lignin content. Additionally, the co-downregulation of three genes, PtrC3H3, PtrC4H1, and PtrC4H2, had the greatest impact on the total lignin content. Secondly, GO and KEGG analysis of lignin-related modules revealed that the total lignin content is not only influenced by monolignol genes, but also closely related to genes involved in the "glutathione metabolic process", "cellular modified amino acid metabolic process" and "carbohydrate catabolic process" pathways. Finally, the cinnamyl alcohol dehydrogenase genes CAD1, CADL3, and CADL8 emerged as potential contributors to total lignin content. The genes HYR1 (UDP-glycosyltransferase superfamily protein) and UGT71B1 (UDP-glucosyltransferase), exhibiting a close relationship with coumarin, have the potential to influence total lignin content by regulating coumarin metabolism. Additionally, the monolignol genes PtrC3H3, PtrC4H1, and PtrC4H2, which belong to the cytochrome P450 genes, may have a significant impact on the total lignin content. Overall, this study establishes connections between gene expression levels and total lignin content, effectively identifying genes that have a significant impact on total lignin content and offering novel perspectives for future lignin research endeavours.

A Green and Ecobenign Protocol for Reduction of Graphene Oxide Using Curry Leaf and Tulsi Seed Extracts and Their Catalytic, Dye Removal, and Antimicrobial Applications

The present work involves an eco-friendly, green, and cost-efficient synthesis of reduced graphene oxide using green extracts of curry leaves and Tulsi seeds as reducing agents. The synthesized reduced GOs (CL-rGO and TS-rGO) were confirmed by XRD, FESEM, EDS, FT-IR, UV-VIS, and TGA studies. The disappearance of the peak at 9.90° and the appearance of a new peak at 2θ = 24.56° and 2θ = 25.62° and a decrease in interlayer spacing from 0.88 nm to 0.34 nm and 0.36 nm in CL-rGO and TS-rGO respectively confirmed the synthesis of reduced GO. The C/O atomic ratio of CL-rGO and TS-rGO was found 4.35 and 4.19 as compared to synthesized GO (C/O atomic ratio 2.65) which confirmed the synthesis of reduced GO. Further, the catalytic applications of synthesized CL-rGO and TS-rGO were studied for the reduction of cinnamaldehyde to cinnamyl alcohol in an aqueous medium yielding 90-91%. Moreover, the degradation of methylene blue and malachite green dyes was studied and found that both dyes were eliminated within 25 and 30 min in dark conditions using CL-rGO and TS-rGO respectively. Both CL-rGO and TS-rGO showed significant antimicrobial activity against different fungal strains but specifically CL-rGO against M. furfur with the minimum inhibitory concentration of 125 µg/mL. Furthermore, CL-rGO and TS-rGO exhibited excellent antimicrobial activity against E. coli with minimum inhibitory concentrations of 62.5 µg/mL and 31.25 µg/mL, respectively.

Construction of modularized catalytic system for transfer hydrogenation: Promotion effect of hydrogen bonds

The construction of enzyme-mimicking catalysts is a crucial route for achieving green chemical transformations; however, integrating multiple sites into one catalyst is challenging. Herein, a facile method is reported to combine different active sites by constructing a modularized catalytic system. A modularized catalytic system composed of covalent organic frameworks (COFs) and Cu2Cr2O5 exhibits remarkable efficiency in the transfer hydrogenation of cinnamaldehyde, with a selectivity of over 99% towards cinnamyl alcohol, surpassing the reaction rate of Cu2Cr2O5 by more than fourfold. The results of the mechanistic study and density functional theory calculations suggest that the enhanced activity of the modularized catalytic system is derived from the hydrogen bonds between the COFs and isopropyl alcohol, which promote isopropyl alcohol dehydrogenation and hydride transfer. In addition, the modularized catalytic system is efficient for various saturated and unsaturated aldehydes and could be replaced by different submodules. This study demonstrates the efficiency of a modularized catalytic system for mimicking the functions of enzymes in catalysis.

Wheat dihydroflavonol-4-reductase like gene confers disease resistance by modulating NADPH pool and lignin biosynthesis

Hm1 is the first cloned disease resistance gene (R) from maize which encodes an enzyme that detoxifies Helminthosporium carbonum (HC) toxin from the fungal pathogen Cochliobolus carbonum. The homologous genes for Hm1 have been mined in various crop plants and their sequences are showed similar to dihydroflavonol-4-reductase (DFR), a key enzyme in flavonoid biosynthesis, therefore they are collectively named dihydroflavonol-4-reductase like (DFRL). The biological functions of DFRL are largely elusive. In the present study, DFRL gene was cloned from wheat, namely TaDFRL. TaDFRL was barely expressed in leaf, stem and root tissues; however, its expression level was rapidly increased following rust infection. Biochemical analysis showed that TaDFRL had the broad spectrum of substrate preference, including dihydroflavonol, flavonol and flavone, and could use both NAD and NADP as co-enzyme, which was quite distinct from DFR. Overexpressing TaDFRL in tobacco altered NAD(H) and NADP(H) pools towards to high NADPH levels. Subsequently, the gene expression of cinnamyl alcohol dehydrogenase (CAD) was up-regulated and lignin accumulation was increased. These brought about to enhance resistance to wildfire disease in tobacco plants. This research provides novel insights into DFRL mechanism, which boost host defense responses by elevating NADPH level and lignin biosynthesis.

Molecular hydrogen-based irrigation extends strawberry shelf life by improving the synthesis of cell wall components in fruit

Strawberries (Fragaria × ananassa Duch.) are highly perishable due to their soft texture, and easily decay during transportation and storage. Our previous report showed that molecular hydrogen-based irrigation in the form of hydrogen nanobubble water (HNW) could obviously improve flavor and consumer preferences of strawberry fruit at the harvesting stage. This study further investigated whether this approach could influence the shelf life of strawberry. During storage for 15 d at 4 ℃, HNW delayed the degradation in the quality of strawberry fruit, evaluated by alteration in sensory attributes (including aroma, luster, color, shape, and general evaluation), weight loss, contents of vitamin C, soluble sugar, and titratable acidity, and sugar/acid ratio. The higher levels of lignin, cellulose, and hemicellulose were observed. Compared to conventional surface water (control) irrigation, the firmness of fruit was increased by HNW irrigation at the harvest stage, and progressively maintained during the storage period. Molecular evidence revealed that before the harvesting period, the transcripts of cinnamyl CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD), as well as cellulose synthase 1/4/6 (CesF1/4/6), the representative genes for the synthesis of lignin, cellulose, and hemicellulose, were induced by HNW irrigation. These changes were positively matched with the increased lignin, cellulose, and hemicellulose contents at the harvesting period. Overall, the extended shelf life of strawberries achieved by molecular hydrogen-based irrigation might be due to the improvement in lignin, cellulose, and hemicellulose accumulation. Therefore, this study demonstrated the effectiveness of HNW irrigation for retarding the decay of harvested strawberries.

The Kinetics and Mechanism of Oxidation of Cinnamyl Alcohol by N-Chloro p-toluene Sulphonamide (Chloramine-T) in Acid Perchlorate Medium

The Kinetics and Mechanism of Oxidation of Cinnamyl Alcohol by N-Chloro p-toluene Sulphonamide (Chloramine-T) in Acid Perchlorate Medium

Adsorption of PPL on a high thermal stable DUT-5 and their catalytic activity in a transesterification reaction of cinnamyl alcohol and vinyl acetate

Lipase-assisted catalytic esterification reactions have been concentrated on due to their green synthetic route for cinnamate acetate. In this paper, a high thermal stable Al-MOF (DUT-5) was chosen as a carrier to immobilize Porcine pancreatic lipase (PPL), and the resulting composites of PPL@DUT-5 were then employed in the catalytic transesterification reaction of cinnamyl alcohol and vinyl acetate. The adsorption conditions of PPL on the surface of DUT-5 were varied to optimize PPL loading uptakes, the adsorption kinetics were analyzed to explore the adsorption behavior of PPL on the DUT-5. In the catalytic transesterification reaction, the resulting PPL@DUT-5 represents the prominent enhanced catalytic stability under a varied reaction condition but with a higher catalytic activity, such as under the relative wide optimum pH value and at the increased operation temperature. And, the good reusability of the PPL@DUT-5 in cyclic catalytic processes highlights their prospect applications in the practical organic conversion reactions.

Meyerozyma guilliermondii promoted the deposition of GSH type lignin by activating the biosynthesis and polymerization of monolignols at the wounds of potato tubers

Lignin is a crucial component in the wound tissue of tubers. The biocontrol yeast Meyerozyma guilliermondii increased the activities of phenylalanine ammonia lyase, cinnamate-4-hydroxylase, 4-coenzyme coenzyme A ligase, and cinnamyl alcohol dehydrogenase, and elevated the levels of coniferyl, sinapyl, and p-coumaryl alcohol. The yeast also enhanced the activities of peroxidase and laccase, as well as the content of hydrogen peroxide. The lignin promoted by the yeast was identified as guaiacyl-syringyl-p-hydroxyphenyl type using Fourier transform infrared spectroscopy and two-dimensional heteronuclear single quantum coherence nuclear magnetic resonance. Furthermore, a larger signal area for G2, G5, G'6, S2, 6, and S'2, 6 units was observed in the treated tubers, and the G'2 and G6 units were only detected in the treated tuber. Taken together, M. guilliermondii could promote deposition of guaiacyl-syringyl-p-hydroxyphenyl type lignin by activating the biosynthesis and polymerization of monolignols at the wounds of potato tubers.