Lignin separated from the pulping and bio-refining industry is a cross-linked organic phenolic polymer and the most abundant renewable aromatic resource. However, its wide molecular weight ...distribution, inhomogeneity and complex functional groups are the factors restricting the application of lignin. The preparation of lignin with simple structures and low dispersity by fractionation is one of the main methods to transform lignin into higher-value materials. In this study, lignin fragments with lower dispersibility (Đ) were separated from CAOSA-extracted bamboo lignin by continuous organic solvent fractionation involving ethyl acetate, ethanol, acetone and dioxane/water (95:5). The lignin fragments extracted by ethyl acetate possessed a lower molecular weight (821 g/mol), lower glass transition temperature (Tg), higher purity and phenolic hydroxyl content (0.370 mmol/g). This method unlocked the versatility of the lignin components and provided a reference for the application of lignin in resin, rubber, antioxidant, asphalt and adhesive.
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•Ethyl acetate fractionation improved the homogeneity of the lignin fragments.•The lignin extracted by ethyl acetate had a higher content of phenolic hydroxyl.•The fractionated lignin was diverse in primary bonds and structures.
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•Stable ε-antimonene nanosheet (ε-SbNS) possesses an energy band gap of 0.461 eV.•The adsorption of ethyl acetate (EA) and isopropyl acetate (IPA) molecules on ε-SbNS are ...investigated.•The transfer of charge occurs between ε-SbNS and target EA and IPA molecules.•ε-SbNS can be deployed as chemical sensor towards EA and IPA molecules.
We deployed ε-antimonene nanosheet (ε-SbNS) as a chemical sensor to sense ethyl acetate (EA) and isopropyl acetate (IPA) molecules at ambient conditions. At first, the structural firmness of ε-SbNS is validated with the support of formation energy, phonon band spectrum, and elastic constants. Further, the electronic properties of the ε-SbNS are conversed using the projected density of states (PDOS) and band structure. The band gap value of ε-SbNS is calculated to be 0.461 eV. Importantly, the adsorption behaviour of chief EA and IPA molecules is studied by determining parameters Bader charge transfer, adsorption energy, and relative energy gap variation. The range of adsorption energy (−0.026 eV to −0.283 eV) reveals that the EA and IPA are physisorbed on ε-SbNS. The findings suggested that ε-SbNS can be employed as a chemical sensor to detect the acetate ester molecules emitted from paint and varnish industries.
Low-temperature operation is a great challenge facing rechargeable batteries, and insufficient ionic conductivity and freezing of electrolyte are generally considered as the main reasons for this ...issue. Herein, an ethyl acetate-based electrolyte with a sufficient ionic conductivity of 0.2 mS cm−1 at the ultra-low temperature of −70°C is first used to fabricate intercalation compounds-based Li-ion batteries (LIBs) and an organic electrodes-based rechargeable battery, respectively, to clarify their low-temperature behavior. It is demonstrated that the LIBs cannot work at −70°C because of the sluggish desolvation of Li+. However, the rechargeable battery using organic electrodes can work well at such low temperature and retains ∼70% of capacity at room temperature, owing to the fast kinetics of charge storage on the surface groups or in the large interstitial space of organic solids. These results indicate a new way for developing low-temperature batteries.
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•An ethyl acetate-based electrolyte is developed for a rechargeable battery•Such electrolyte exhibits sufficient ionic conductivity at low temperature•The sluggish desolvation of Li+ limits low-temperature operation of the battery•Polymer electrodes-based batteries can work well at ultra-low temperature of −70°C
It is a common phenomenon that Li-ion batteries (LIBs) based on intercalation compound electrodes exhibit poor performance when the temperature decreases below 0°C, for which the insufficient ionic conductivity and freezing of electrolyte are generally considered the main reasons. Here we develop an ethyl acetate-based electrolyte, which exhibits sufficient ionic conductivity at the ultra-low temperature of −70°C. Based on such an electrolyte, rechargeable batteries using intercalation compounds and organic polymers, respectively, as electrodes have been fabricated. However, intercalation compounds-based LIBs still cannot work at −70°C owing to the sluggish solvation/desolvation of Li+. Benefiting from the fast kinetics of charge storage properties, the rechargeable battery using organic electrodes can work well at such a low temperature of −70°C and displays excellent capacity retention at room temperature. These findings might shed light on the development of low-temperature batteries.
An ethyl acetate-based electrolyte, which exhibits a high boiling point, a low freezing point, and a sufficient ionic conductivity at ultra-low temperature of −70°C, was developed. Taking advantage of such an electrolyte, Li-ion full cells based on organic electrodes can work well and show outstanding performance within a wide operation temperature range from −70°C to +55°C.
Sargassum plagyophyllum is a type of brown seaweed containing bioactive components including alkaloids, flavonoids, steroids/terpenoids, saponins and phenolics that have potential as antibacterial. ...This study aims to determine the bioactive components of the S. plagyophyllum extract fraction qualitatively and the antibacterial activity of the S. plagyophyllum fraction by agar diffusion method with wells. The method used in this research is an experiment by extracting and fractionating S. plagyophyllum. Parameter analysis consisted of analysis of bioactive components (alkaloids, flavonoids, steroids/terpenoids, saponins, phenolics) qualitatively and determining antibacterial activity in the S. plagyophyllum fraction against Staphylococcus aureus and Escherichia coli. The results showed that the bioactive components in the methanol extract of S. plagyophyllum contained flavonoids, steroids/terpenoids, saponins and phenolic compounds. The bioactive components in the ethyl acetate fraction contained alkaloids, flavonoids, steroids/terpenoids, saponins and phenolics. The n-hexane and butanol fractions contained steroids/terpenoids, and saponins. The extract fraction of S. plagyophyllum could inhibit the growth of antibacterial activity against S. aureus and E. coli bacteria. The ethyl acetate fraction was the best fraction inhibiting bacterial activity with the highest zone of inhibition compared to other fractions (n-Hexane and buthanol), namely 12.95 ± 0.64 mm for S. aureus bacteria and 10 ± 0.14 mm for E. coli bacteria.
The pulp and pericarp of mangosteen (Garcinia mangostana) fruit are popular food, beverage and health products whereby 60% of the fruit consist of the pericarp. The major metabolite in the previously ...neglected or less economically significant part of the fruit, the pericarp, is the prenylated xanthone alpha-mangostin. This highly bioactive secondary metabolite is typically isolated using solvent extraction methods that involve large volumes of halogenated solvents either via direct or indirect extraction. In this study, we compared the quantities of alpha-mangostin extracted using three different extraction methods based on the environmentally friendly solvents methanol and ethyl acetate. The three solvent extractions methods used were direct extractions from methanol (DM) and ethyl acetate (DEA) as well as indirect extraction of ethyl acetate obtained via solvent partitioning from an initial methanol extract (IEA). Our results showed that direct extraction afforded similar and higher quantities of alpha-mangostin than indirect extraction (DM: 318 mg; DEA: 305 mg; IEA: 209 mg per 5 g total dried pericarp). Therefore, we suggest that the commonly used method of indirect solvent extraction using halogenated solvents for the isolation of alpha-mangostin is replaced by single solvent direct extraction using the environmentally friendly solvents methanol or ethyl acetate.
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•Trichoderma spp. were screened for anti-Phytophthora activity.•Trichoderma atroviride/petersenii (KACC 40557) showed the best anti-Phytophthora activity.•Trichoderma metabolite ...treatment caused plant hormonal and transcriptional changes.
Trichoderma species are well-known biological control agents. In this study, metabolites from 128 Trichoderma isolates were extracted from liquid cultures using ethyl acetate and tested for their activities against seven Phytophthora isolates. Following preliminary analysis, eight Trichoderma isolates were selected for further tests. Among them, the metabolites from Trichoderma atroviride/petersenii (KACC, Korea Agricultural Culture Collection, 40557) and Trichoderma virens (KACC 40929) showed the strongest inhibitory activities against Phytophthora isolates. Treatment with KACC 40557 extract inhibited Phytophthora growth, induced defense-related genes, and caused plant hormonal changes during Phytophthora infection in the detached leaves of pepper and tomato plants. Our results showed the potential for use of Trichoderma metabolites as biological control agents against Phytophthora pathogens.
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