Alcohol Compounds Research Articles

Enhancing efficiency of solvent-free oxidation of aromatic alcohols with atmospheric oxygen by POSS-based cationic polymer backbone paired heteropolyanions

Oxidation is among the most crucial reactions for the production of chemicals and many noble metals are the efficient active centers. The catalysts derived from non-noble metal species are preferred thanks the low cost and earth abundance but suffered from inferior efficiency to noble metal ones. Herein, we demonstrated an unusual effective non-noble metal heterogeneous catalyst for the solvent-free synthesis of aromatic aldehydes from selective O2-mediated oxidation of alcoholic compounds. The target catalyst was prepared by the copolymerization of divinylimidazole dibromide and polyhedral oligomeric silsesquioxane, followed by loading phosphomolybdenum anions via ion exchange. The catalyst gave high yields of up to 93% towards aldehydes, stable reusability, and extendable substrate scope in transforming aromatic alcohols without any solvent. The high performance comes from the abundant low valence Mo species derived from the strong cation-anion interaction, which promoted the O2 activation to give superoxides (•O2−) as the reactive oxygen species.

Conversion study from lignocellulosic biomass and electric energy to H2 and chemicals

The efficient use of lignocellulosic biomass resources is of great significance to solve environmental pollution and energy crisis. Therefore, the understanding of the reactivity of lignin, hemicellulose, and cellulose, which are the major components of lignocellulosic biomass, on chemical and hydrogen conversion is necessary. So combined with proton exchange membrane electrolysis cell, using polyoxometalate (POM) as the oxidizing agent and electron stockpile carrier, the cyclic electrolytic hydrogen production and degradation of lignin, hemicellulose, and cellulose have been researched in detail. Among them, lignin degraded the best (96.81%), and the average Faradaic efficiency of the herein system was also the highest (95.93%). These results exhibit high conversion efficiency from electric energy to hydrogen energy. Simultaneously, without harsh conditions, lignin is mainly degraded to vanillin, hemicellulose is mainly converted to ester compounds, and cellulose is mainly converted to alcohol compounds, which provides an experiment basis for future chemical conversion.

In vitro cytotoxic effects, in silico studies, some metabolic enzymes inhibition, and vibrational spectral analysis of novel β-amino alcohol compounds

In this study, an efficient single-step method for the preparation of β-amino alcohols (1–3) in aqueous media was applied. The aim was to investigate the cytotoxic activity of Compounds 1, 2 and 3 in neuroblastoma SH-SY5Y cell line and mouse fibroblast l-929 cell lines. Cytotoxic activities of compounds 1, 2 and 3 in this cell lines were also determined by MTT method. Cells were incubated with different concentrations of Compound 3 showed the highest cytotoxic activity in SHY5Y cells at an IC50 dose of 13.01±0.87 µM at 72 h compared to other compounds. Compound 3 was determined to have lower cytotoxic activity in l-929 cells. The chemical activities of the molecules against the B3LYP, HF, M062X level 3–21 g, 6–31 g, and SDD basis set with the Gaussian package program and biologically against the adenosine A(2A) receptor (PDB ID: 3PWH and 5NM4) proteins for neuroblastoma tumors cell with the Maestro Molecular modeling platform by Schrödinger were compared. Both experimental and theoretical NMR, UV–vis, and IR spectra of the studied molecules were compared. ADME/T analysis was performed to examine the drug properties of the molecules. Finally, these assayed for their activities against metabolic enzymes acetylcholinesterase and α-glucosidase. The most potent compounds against AChE were order compounds 3, 2 and 1 with Ki values of 35.88±6.61, 43.75±8.28, and 45.34±3.50 µM against AChE, respectively. The results indicated that all the synthesized compounds exhibited excellent inhibitory activities against mentioned enzymes as compared with standard inhibitors. These inhibitors may be candidates for drug design.

Pyrolysis of Polyolefins into Chemicals Using Low-Cost Natural Zeolites

An experimental study of pyrolysis from polyethylene (PE) and polypropylene (PP) has been done by catalytic method and utilization of low-cost natural zeolite in a semi-batch reactor. A low-cost natural zeolite made from acid-treated zeolite with 1 M HCl solution was denoted as HZ. The prepared HZ catalyst was then carried out under pyrolysis reaction at 350, 400, 450 °C for 60 min. The chemical products composition from this reaction was analyzed using Gas Chromatography-Mass Spectrometry (GC–MS). According to the analysis result, a low-temperature reaction of pyrolysis could produce wax in all variant types of feed. Utilization of HZ catalyst could reduce formation wax while also increasing the yield of oil products after the reaction. Catalytic pyrolysis using HZ for PE and PP plastic feed yields oil products up to 67% and 70%, respectively. The composition of oil products mainly consisted of paraffin, olefin, and alcohol compounds. The temperature optimum for the catalytic reaction could produce the highest paraffin and olefin products at 400 °C. Additionally, utilization of low-cost natural zeolite could improve pyrolysis reaction's performance from PP to produce yield olefin products from 39 to 62%.Graphical Abstract

Dormancy and germination of microsclerotia of Verticillium longisporum are regulated by soil bacteria and soil moisture levels but not by nutrients

The soil-borne pathogen Verticillium longisporum infects roots of its host plant, oilseed rape, and systemically colonizes stems where it finally forms microsclerotia at crop maturity. Once returned to the soil after harvest, microsclerotia undergo a stage of dormancy, in which they may survive for several years. Since there is neither efficient chemical control nor effective resistance in oilseed rape cultivars to control the disease, alternative control strategies may consist in regulating the germination and dormancy of microsclerotia in the soil. Therefore, a series of experiments were conducted to explore the effects of nutrients, soil moisture, and the soil microbiome on germination of dormant microsclerotia. Experiments with microsclerotia exposed in vitro to different nutrients indicated that under sterile conditions the stimulating effect of nutrients on microsclerotia germination was not enhanced as compared to water. Moreover, further assays revealed a strong inhibitory effect of unsterile soil on microsclerotia germination. Accordingly, oilseed rape plants inoculated with microsclerotia of V. longisporum showed severe infection with V. longisporum when grown in autoclaved soil, in contrast to plants grown in unsterile soil. These experiments indicate a crucial role of soil fungistasis and thus the soil microbiome on microsclerotia germination. Further bioassays demonstrated that viable soil bacteria obtained from the rhizosphere of oilseed rape plants and bulk field soil effectively inhibited microsclerotia germination, whereas dead bacteria and bacterial culture filtrates hardly suppressed germination. A putative inhibitory role of volatile organic compounds (VOCs) produced by soil bacteria was confirmed in two-compartment Petri dishes, where microsclerotia germination and colony growth were significantly inhibited. Bacterial VOCs were collected and analyzed by GC–MS. In total, 45 VOCs were identified, among which two acid and two alcohol compounds were emitted by all tested bacteria. A bioassay, conducted with corresponding pure chemicals in two-compartment Petri dishes, indicated that all acidic volatile compounds, including 3-methylbutanoic acid, 2-methylbutanoic acid, hexanoic acid, and 2-methylpropionic acid, induced strong inhibitory effects on microsclerotia. We conclude that bacterial acidic volatiles play a key role in the fungistatic effect on microsclerotia of V. longisporum in the soil and could thus be targeted for development of novel strategies to control this pathogen by artificially regulating dormancy of microsclerotia in soil.

Effect of ultrasonic non-thermal sterilization on the volatile components of pumpkin juice

The objective of this study was to investigate the effects of ultrasonic treatment on the aroma profile of pumpkin juice. Samples were treated according to the experimental design, with a numerically controlled ultrasonic instrument at an ultrasound frequency of 45 kHz under various conditions (treatment times of 10, 20, and 30 min, sample temperature of 25(± 2)∘C, and powers of 180, 240, and 300 W). The aromatic profiles of pumpkin juice showed that a total of 52 volatile components were detected in the 10 groups of pumpkin juices, including 16 alcohols, 11 alkane olefins, 6 aldehydes, 4 ketones, 4 esters, and 11 others. Alcohol compounds had the highest content among all volatile compounds; the most abundant were 1-Octen-3-ol, (E, Z)-3, 6-Nonadien-1-ol, 1-hexanol, and (Z) -3-Nonen-1-ol. Compared to the untreated samples of juices, ultrasonic treatment leads to the formation of new compounds or the disappearance of compounds found in the untreated samples. The findings presented in this study provide a deeper understanding of the application of ultrasound to enhance the volatile components of pumpkin juice.

Eugenol-derived Organic Liquids as an In-Situ CO2 Capturing and Conversion System for Eugenol-based Polycarbonate Synthesis.

The significant development of catalytic biomass conversion has provided a large library of chemicals ready for subsequent upgrading to polymerisable monomers for the design and preparation of sustainable polymers. In this study, hydroxyethylation of eugenol by using green ethylene carbonate as alkylation reagent and cheap tetrabutylammonium iodide ionic liquids as green solvents and catalysts produced 2-(4-allyl-2-methoxyphenoxy)ethan-1-ol with a 85% yield, which could be used to construct an in situ CO2 capture and conversion system by taking the reversible chemistry of alcoholic compounds with CO2 in the presence of superbases, on which α,ω-diene functionalized carbonate monomers were successfully prepared and were applied in thiol-ene click and acyclic diene metathesis polymerisation (ADMET), producing a series of poly(thioether carbonate)s and unsaturated aromatic aliphatic polycarbonates with moderate molecular weights and satisfactory thermal properties. The structures of the formed CO2 reversible ILs, the polymerisable monomers and the corresponding polymers were fully characterized by various technologies.

Comparison of Pyrene Biodegradation Using Two Types of Marine Bacterial Isolates

Polycyclic aromatic hydrocarbons (PAHs) contaminants have toxic, carcinogenic, and mutagenic properties. Screening bacteria from different sources capable of carrying out the biodegradation of (PAHs) is essential for mapping and mobilization purposes and applying them to polluted hydrocarbon environments. The study aims to compare the capacity of PAH biodegradation by two types of bacteria isolated from different sources. The method applied is the interaction between bacterial suspension and pyrene-contaminated waste for 30 days. Biodegradation products in organic compounds were analyzed using gas chromatography/mass spectroscopy (GC/MS) and Fourier transform infrared spectroscopy (FTIR). The analysis results found several indications of the performance of bacterial biodegradation: The capacity of pyrene degradation by Bacillus licheniformis strain ATCC 9789 (Bl) bacteria against pyrene was relatively more dominant than Sphingobacterium sp. strain 21 (Sb) bacteria. The percentage of total bacterial biodegradation for product type Sb was (39.00%), and that of the product of bacterial degradation type Bl (38.29%). The biodegradation products of the test bacteria (Bl and Sb) were relatively similar to pyrene in the form of alcohol and carboxylic acid organic compounds. There was no significant difference in the pyrene biodegradation between Bl and Sb bacteria.

Metabolic and pharmacological profiling of Penicillium claviforme by a combination of experimental and bioinformatic approaches

Background Penicillium produces a wide range of structurally diverse metabolites with significant pharmacological impacts in medicine and agriculture. For the first time, a complete metabolome of Penicillium claviforme (P. claviforme) (FBP-DNA-1205) was studied alongside pharmacological research in this study. Methods The metabolic profile of P. claviforme fermented on Potato Dextrose Broth (PDB) was investigated in this work. The complete metabolomics studies of fungus were performed using GC-MS and LC-MS-QTOF techniques. An in vitro model was utilised to study the cytotoxic and antioxidant activities, while an in vivo model was employed to investigate the antinociceptive and acute toxicity activities. Molecular Operating Environment (MOE) software was used for molecular docking analysis. Results GC-MS study showed the presence of alkanes, fatty acids, esters, azo and alcoholic compounds. Maculosin, obtain, phalluside, quinoline, 4,4’-diaminostilbene, funaltrexamine, amobarbital, and fraxetin were among the secondary metabolites identified using the LC-MS-QTOF technique. The n-hexane fraction of P. claviforme displayed significant cytotoxic activity in vitro, with an LD50 value of 92.22 µgml−1. The antinociceptive effects in vivo were dose-dependent significantly (p < .001). Interestingly, during the 72 h of investigation, no acute toxicity was demonstrated. In addition, a docking study of tentatively identified metabolites against the inflammatory enzyme (COX-2) supported the antinociceptive effect in an in silico model. Conclusion Metabolic profile of P. claviforme shows the presence of biologically relevant compounds in ethyl acetate extract. In addition, P. claviforme exhibits substantial antioxidant and cytotoxic activities in an in vitro model as well as antinociceptive activity in an in vivo model. The antinociceptive action is also supported by a molecular docking study. This research has opened up new possibilities in the disciplines of mycology, agriculture, and pharmaceutics. Key messages The first time explored complete metabolome through GC-MS and LC-MS-QTOF. Both in vivo & in vitro pharmacological investigation of P. claviforme. In silico molecular docking of LC-MS-QTOF metabolites.

Phenol-cyclohexanol eutectic mixtures: Phase diagram and microscopic structure by experimental and computational studies

• Non ionic eutectic solvents: phenol-cyclohexanol mixture. • SLE phase diagram by DSC experiment. • Microscopic structure and hydrogen bonding by IR spectroscopy, X-ray diffraction and theoretical calculations. Non ionic deep eutectic solvents (type V) have been recently proposed as innovative and alternative solvents. Prepared by mixing the starting components, their mixtures show strong deviations from thermodynamic ideality. An example of deep eutectic solvent is the 1:1 thymol-menthol mixture: deviations from ideality are originated from the strength of the hydrogen bond between different components. With the aim to investigate the role of hydrogen bonding in the non-ideality of mixtures of phenolic and alcoholic compounds, we studied the phase diagram and the structural properties of cyclohexanol and phenol mixtures coupling experimental and computational techniques. The phase diagram was measured by differential scanning calorimetry (DSC) providing a lowest melting point at about -35°C . The microscopic structure of eutectic composition was characterized by infrared spectroscopy (FT-IR), DFT and classical molecular dynamic simulations. The X-ray pattern was compared with MD results with the aim to describe the intermolecular interactions between phenol and cyclohexanol. The deviations from ideal mixing seem to be smaller than those observed for the 1:1 thymol-menthol mixture. The nature of intermolecular interactions in the phenol-cyclohexanol system has been compared with that of the thymol-menthol system by quantum chemistry calculations. In both the systems heteroassociation is energetically preferred to homoassociation because hydrogen bonding is stronger between different components, however van der Waals contributions involving alkyl groups can play an additional and significant role in the intermolecular association of the thymol-menthol system.

Spectroscopic Analysis and ADME Studies of Phytochemicals in Methanolic Leaves Extract of Sonneratia apetala Buch.-Ham

The plants are enormous source of medicinally important ingredients. The separation of active plants compounds leads to discovery of many drugs derived directly from plants. In the current study, The HPLC analysis is carried for the methanolic extracts of gives different peaks at 254 nm, it may be alcoholic compound. The FTIR spectrum confirmed the presence of alcohol, alkanes, carboxylic acid, aromatics, esters and ethers in methanolic extract of Sonneratia apetala. UV-Visible profile showed different peaks ranging from 200-800 nm with different absorption respectively. In silico study, especially physicochemical properties, lipophilicity, water solubility, pharmacokinetics, drug likeness and medicinal chemistry performed by using the Swiss ADME online tool.

FTIR screening of phytocompounds in plant Spermacoce hispida L. of Vallimalai Hills at Vellore district

The objective of this study is to detect the FTIR fingerprints of phytocompounds in the plant Spermacoce hispida L. The FTIR analysis of methanol leaf extract of plant Spermacoce hispida L. revealed the presence of 19 bioactive phytocompounds such as aliphatic primary amine, alkene, alkanes, amine salt, aldehydes, aromatic compound, α, β-unsaturated ester, conjugated alkene, nitro compound, sulfonyl chloride, phenol, aromatic amine, alkyl aryl ether, vinyl ether, ester, tertiary alcohol, primary alcohol, carboxylic acids and halo compound.

Hydrogenation of alkynyl ketones catalyzed by tetrabutylammonium bromide

<p indent="0mm">Propargyl alcohol compounds have many applications in medicine, pesticides and functional molecular materials, and are also important intermediates in organic synthesis because they contain alkynyl and hydroxyl groups in the molecules. The common preparation methods for propargyl alcohol usually rely on the transition metal catalyzed hydrogenation reaction and the alkynylation of ketones, which is high cost and with poor tolerance of the substitution groups. In this article, the hydrogenation reaction of alkynyl ketones with pinacolborane was developed with tetrabutylammonium bromide as catalyst. The present method provided a convenient, economical and efficient method for the synthesis of propargyl alcohol compounds.

Bio-efficacy of Geobacillus thermodenitrificans PS41 against larvicidal, fungicidal, and plant growth-promoting activities.

The microbial interactions with plant hosts were known to establish plant growth and beneficial productivity. Some bacteria, fungi, actinomycetes, yeast, and algae have proven as potential effective microbes in agricultural field. In this study, the insecticidal effect of Geobacillus thermodenitrificans PS41 secondary metabolites was tested against third instar larvae of Spodoptera litura, with mortality rate 60.26 ± 1.5% which might influence the agropest management. The test bacterial metabolites were subjected to GC-MS analysis. Totally, 17 different compounds were identified from the ethyl acetate extract metabolites of PS41 strain. The highest peak was obtained with behenic alcohol compound followed by 1-octadecene and penta erythrityl tetrachloride. The Geobacillus thermodenitrificans PS41 secondary metabolites showed potential antifungal activity against plant pathogenic fungi. The highest inhibit was attained against Cladosporium sp., (25 mm) followed by Rhizoctonia solani and Alternaria brassicola (23 mm). However, no toxic effect was exerted upon earthworm (Perionyx excavatus) when treated with PS41 bacterial metabolites. The potential PS41 strain was also found supporting the plant growth. The potential bacterial strain PS41 did not show antagonistic activity against soil bacteria such as Rhizobium sp., Azotobacter sp., Azospirullum brasilense, Pseudomonas fluorescens and Bacillus megaterium. The potential test organism, Geobacillus thermodenitrificans PS41, possessing biopesticide and biofertilizer properties can be a suitable ecofriendly organic applicant in agricultural field for enhancing crop production.

Agile Construction of Porous Organic Frameworks Pending Carboxylic Acids and Imidazolium-Based Ionic Liquids for the Efficient Fixation of CO2 to Cyclic Carbonates

The design and facile preparation of ionic liquids (ILs)-functionalized polymer materials is a hot research topic due to their potential wide applications. Herein, taking the reaction advantage of a cyclic anhydride with an alcoholic compound to atom-economically generate a carboxyl ester pending a carboxylic acid moiety, porous organic framework (POF) materials pending carboxylic acids and imidazolium-based ILs (CILs-POFm) were facile synthesized via the acylation reaction of hydroxyl group-functionalized ILs with a styrene maleic anhydride copolymer. The CILs-POFm material properties were facilely adjusted by changing the molar ratio of the mono-hydroxyl-functionalized ILs to the dihydroxyl-functionalized ILs. CILs-POFm materials showed abundant mesoporous structures with a porous diameter of approximately 23.83–48.16 nm, a surface area of up to 274.4 m2 g–1, and a superior CO2 adsorption capacity of 1.71–2.14 mmol g–1 at 273 K and 1 atm. As a proof of concept application, the coupling reaction of epoxides with CO2 to produce cyclic carbonates was studied by using the CILs-POFm materials as catalysts under solvent-free and co-catalyst-free conditions. The findings indicated that the CILs-POF0.5 exhibited a satisfactory catalytic activity and reusability for a large scope of epoxides. Based on the experimental results and density functional theory (DFT) simulations, a synergetic catalytic mechanism was proposed based on the pended carboxylic acidic groups and IL groups. This study not only provided an atom-economic strategy to prepare POFs pending both carboxylic acids and ILs, but also showed new insights into the design of functionalized POF materials with great application potential in energy storage materials, separation, and green catalysis.

SYNTHESIS OF AMINOMETHOXY DERIVATIVES OF CYCLOHEXANOL AND STUDYING THEM AS BACTERICIDE INHIBITORS

Based on cyclohexanol, cyclic amines (piperidine, morpholine, hexamethyleneimine), and formaldehyde, new Mannich bases have been synthesized. The reaction was carried out at a temperature of 78–800C for 4–5 h in a benzene solution at an equimolar ratio of the starting components. The yield of compounds was 69–75%. The physicochemical data of the synthesized compounds were determined. The composition and structure of the target products were confirmed by elemental analysis, IR, 1H and 13C NMR spectroscopy, and mass spectrometry. Their effect on the vital activity of sulfate-reducing bacteria of the "Desulfovibrio desulfuricans" type at three concentrations (25; 50; 100 mg/l) was studied. The obtained compounds showed high bactericidal properties, 1% solutions of these compounds in isopropyl alcohol at a concentration of 100 mg/l showed 100% bactericidal effect. A 1% solution of the compound with a fragment of morpholine already at a concentration of 50 mg/l exhibits a 100% bactericidal effect. Compounds with a fragment of piperidine and hexamethyleneimine at a concentration of 50 mg/l showed 96.2 and 98% bactericidal effects, respectively. And at a concentration of 25 mg/l, the bactericidal effect of all three compounds was 16.4%, 36.4%, and 58.2%, respectively. The results obtained show that the synthesized compounds showed more bactericidal properties compared to the industrially used bactericide-inhibitors АМДОР ИК-7 and АМДОР ИК-10 taken as a standard. Established, that these aminomethoxy derivatives of cyclohexanol affect bacteria at very low concentrations, they can be proposed as effective inhibitors against sulfate-reducing bacteria

WITHDRAWN: Acetate derivative of Morita –Baylis-Hillman adducts (MBH): A powerful antifungal

In previous work, a new class of synthesized bioactive compounds of Morita –Baylis-Hillman adducts (MBH) showed an antioxidant and anti melanogensis activity. Accordingly, in the present work the relationship between antifungal activity and the responsible chemical function of MBH adducts and their derivatives (alcohols, acetates, phosphonates and hydrazono phosphonates) was investigated against plant pathogenic fungi Aspergillus niger, Fusarium oxysporum, Penicillium occitanis, Trichoderma reesei, Stachybotrys microspora, Fusarium solani, Trichoderma parceramosum, fusarium aethiopicum, Alternaria alternata and Aspergillus flavus using the agar diffusion method. Results showed acetates displayed varying degrees of antifungal activity against several fungi tested, while just one alcohol compound showed lower activity. The derivative with five carbon (2g) was the most powerful with an inhibitor growth zone diameter of 4.75÷0.21, 6.1±0.14, 4.35±0.21, 3.9±0.14, 4.54± 0.11, 3.55±0.07, 3±0, 3.2± 0.2, 5.36 ± 0.26 and 5.06± 0.5cm against; F. oxysporum, T. parceramosum, S. microspora, T. reesei, F. solani, P. occitanis, A. niger, F. aethiopicum, A. alternate and A. flavus respectively. Compared to the positive control the nystatin, most of the tested compounds exhibited moderate to strong inhibitory effects. The antifungal activity depended on the radical group. The novelty is that these adducts are evaluated for the first time for their antifungal effect. Antifungal activity is in general of linear or cyclic molecules coupled to six carbons. Here we show that the simple acetate six membered carbons are the most efficient molecule

AMINOMETHOXY DERIVATIVES OF CYCLOHEXANOL AS BIOCORROSION INHIBITORS

Based on cyclohexanol, aliphatic amines (diethylamine, dipropylamine, dibutylamine, dihexylamine), and formaldehyde, new Mannich bases have been synthesized. The reaction was carried out at a temperature of 78–80°C for 4–5 h in a benzene solution at an equimolar ratio of the starting components. The yield of compounds was 63–80%. The physicochemical data of the synthesized compounds were determined. The composition and structure of the target products were confirmed by elemental analysis, IR, 1H and 13C NMR spectroscopy. Their influence on the vital activity of sulfate-reducing bacteria (SRB) of the "Desulfovibrio desulfuricans" type at three concentrations (25; 50; 100 mg/l) was studied. The resulting compounds showed high bactericidal properties. 1% solutions of these compounds in isopropyl alcohol at a concentration of 100 mg/l showed a 100% bactericidal effect. Given that these aminomethoxy derivatives of cyclohexanol affect bacteria at very low concentrations, they can be proposed as effective inhibitors against sulfate reducing bacteria. Keywords: cyclohexanol, aliphatic amines, Mannich bases, sulfatereducing bacteria, inhibitor-bactericides, biocorrosion.

PYROLYSIS KINETICS OF KEYBOARD PLASTIC WASTE USING THERMOGRAVIMETRIC ANALYSER TO ASSESS ITS ENERGY POTENTIAL

In this paper, the kinetic parameters of discarded computer keyboard plastic waste are estimated using thermogravimetric analysis (TGA) with four different non-isothermal kinetic models at a wide range of heating rates 5, 10, 15, 20, 40, 60 and 100 °C/min. The gross calorific value of waste computer keyboard plastic is 38.96 MJ/Kg. FT-IR analysis confirms the presence of alcohol, phenol, ether, ester, carboxylic acid, aromatic, and alkene compounds in keyboard plastic waste. The average values of activation energy are calculated as 158.1668, 198.883, 193.612, and 197.765 kJmol−1 from Kissinger, Friedman, FWO, and Coats-Redfern methods, respectively. The kinetic data obtained in this work would be useful for accurate prediction of reaction behaviour and in the design of efficient commercial process for the conversion of such plastic wastes to energy.

Volatile Composition of Sparkling Wines of cv. Chardonnay Cultivated under Different Training Systems in Serra da Mantiqueira (Brazil).

The grapevine is a climbing plant and allows for the manipulation of vegetative canopies to change the microclimate and exposure of leaves and clusters to solar radiation, affecting the primary and secondary metabolisms of plants. Thus, this work aimed to evaluate how the lyre and Geneva double-curtain (GDC) training systems could contribute to the volatile composition of sparkling wines in replicates of vinifications carried out in the Serra da Mantiqueira (Brazil) in two consecutive summer harvests (2017 and 2018). Fifty-four free volatile compounds were identified by HS-SPME/GC-MS in the wines in both systems and vintages. Multivariate analysis differentiated the vintages in component 1 (22.7%) and the training systems in component 2 (7.1%). The crops were differentiated by aldehydes in 2017 and in 2018 by isoamyl acetate ester, probably derived from the amino acid leucine, the season having been more humid, with lower temperatures and less radiation. For the training systems, besides the alcohol compounds, the GDC was differentiated by the terpenoid compounds geranylacetone and β-damascenone, which may contribute more pleasant aromas to sparkling wines. This work promotes additional research and enables winegrowers, through the management of their vineyards, to achieve sparkling wines with different volatile compositions.