Chemical Structure Research Articles

An ABC transporter-mediated transport and metabolism of the pesticide bentazone in rice (Oryza sativa L.)

IntroductionBentazon (BNTZ) is a selective contact herbicide widely used to control field weeds for crop production. Excessive use of BNTZ leads to its accumulation in soils and crops, becoming an environmental contaminant. Therefore, investigation of the mechanisms for BNTZ detoxification and degradation in crops is fundamentally important to reduce crop contamination and ensure food safety. ObjectivesThis study aims to elucidate the mechanism of detoxification and degradation pathways of the BNTZ complex in rice by creating transgenic lines expressing a rice ATP-binding cassette (OsABC) transporter gene through genetic engineering techniques combined with chemical analytical techniques and metabolomics approaches. MethodsWe established the rice transgenic lines overexpressing (OE) a rice OsABC transporter and its knockout lines by CRISPR-Cas9 to characterize the gene function and measured the accumulation of BNTZ residues in rice. The metabolites of BNTZ were characterized by LC/Q-TOF-HRMS/MS (Liquid chromatography/time of flight-high resolution mass spectrometry). ResultsOverexpression of OsABC significantly conferred rice resistance to BNTZ toxicity by increasing plant elongation, dry weight, and chlorophyll content, and significantly reducing cell membrane damage and BNTZ accumulation in rice tissues. Six different metabolites and ten conjugates were well defined in chemical structures. The reduced BNTZ levels and degradation products in the grains of the OE lines supported the robust activity of the OsABC gene function.Using UPLC-Q-TOF/MS, we further identified accumulated basic metabolites of various carbohydrates, amino acids, hormones, and flavonoids, and found that these metabolites involved in BNTZ degradation were increased more in OE lines than in wild-type (WT) rice. ConclusionsOur work demonstrates that the OsABC transporter plays a critical role in regulating the mobility and degradative metabolism of BNTZ in rice, thus revealing a regulatory mechanism underlying rice resistance to BNTZ toxicity and adaptation to the environmental stress.

Double layer packaging based on active black chickpea protein isolate electrospun nanofibers and intelligent salep film containing black chickpea peel anthocyanins for seafood products

In this study, a double-layer active and intelligent packaging system was developed based on two main natural macromolecules i.e. protein and carbohydrate with green perspective. Firstly, the salep-based films containing different concentrations (0–8 % w/w) of the inclusion complex of β-cyclodextrin/black chickpea anthocyanins (βCD/BCPA) were produced. The salep film containing 8 % of βCD/BCPA complex was specified as the optimized film sample based on its performance as a color indicator. The electrospinning of black chickpea protein isolate nanofibers (BCPI NFs) containing citral nanoliposomes (NLPs) was done on the optimized salep film. The cross-sectional field emission scanning electron microscopy approved the creation of double-layer structure of the developed film. The study of chemical and crystalline structure, as well as the thermal properties of the film exhibited the physical attachment of BCPI electrospun NFs on salep film. The effectiveness of the developed system was studied in detection of spoilage and increasing the shelf life of seafood products, including shrimp and fish fillet. The performance of the intelligent layer in detection of freshness/spoilage was acceptable for both seafood products. In addition, the active layer of the film controlled the changes of pH, total volatile basic nitrogen, oxidation, and microbial load in samples during storage time.

The Influence of Pore-Forming Diluents on Porous Structure, Thermal and Sorption Properties of the Divinylbenzene and Glycidyl Methacrylate Copolymers.

The aim of this work was the characterization of polymer microspheres obtained by the suspension polymerization of divinylbenzene (DVB) and glycidyl methacrylate (GMA), depending on the pore-forming diluents and molar ratio of monomers. The assessed properties included the chemical and porous structure, thermal stability, and sorption capacity of the obtained polymers towards methylene blue. The abovementioned characteristic was carried out for two series of copolymers with molar ratios of monomers of 1:2, 1:1 and 2:1, synthetized with toluene and a mixture of decanol and benzyl alcohol. The structure of the polymers was confirmed by FTIR and elemental analysis. The results of TGA demonstrated the main influence on thermal stability was the composition of polymers, whereas the impact of porogens was negligible. The SBET varied in the range of 12-534 m2g-1 for polymers obtained with toluene and 0-396 m2g-1 with the mixture of alcohols. Toluene enhanced the formation of micro- and mesopores, while the mixture of alcohols enhanced the creation of meso- and macropores. For the polymers prepared with toluene, their effectiveness in water purification decreases in the following order: DVB-GMA 2:1 > DVB-GMA 1:1 > DVB-GMA 1:2, according to the decreasing values of porous structure parameters. In the case of a series obtained with a mixture of alcohols, such correlation was not observed.

Unlocking the photothermal conversion capacity of lignin and lignin-derived materials

Lignin is the most prevalent polyphenolic organic solid waste generated by the pulping and biorefining industries. It confers upon woody biomass a remarkable combination of physical, chemical, and biological resilience, while simultaneously exhibiting considerable potential for photothermal conversion. In recent years, the utilization of technical lignin and lignin by-products to develop photothermal materials has emerged as a research hotspot. This review introduces the industrial separation processes and characterization of different types of lignin, highlighting the chemical structures of lignin and its derivatives linked to their photothermal conversion mechanisms. The evaluation pathways for photothermal conversion are summarized and critically assessed, as guided by mathematical descriptions of best practices in lignin-derived materials. This review covers and reflects on recent and emerging advances in materials and energy sciences that demonstrate how lignin can be utilized to maximize solar-to-thermal conversion and versatility in desalination, electricity generation, therapy, and intelligent and environmentally friendly building materials. Finally, the challenges and proposed future directions for the development of lignin-derived photothermal materials are identified with the objective of challenging the prevailing notion that lignin is merely an organic solid waste.

Novel insight into calcium-catalyzed steam gasification behaviors of lignite

Lignite is a low-rank coal with abundant reserves, and direct combustion causes serious environmental pollution. Calcium-catalyzed steam gasification is a cleaner technology that can convert lignite into high-value fuels and chemicals. However, the detailed structural evolution of calcium species during lignite steam gasification remains inadequately understood. The present work addresses this issue by subjecting the calcium-catalyzed steam gasification process of lignite to a detailed analysis, focusing on both the pyrolysis and gasification stages. The transitions in the chemical structures of the lignite and calcium catalysts during the pyrolysis stage were investigated in situ by Fourier Transform Infrared Spectroscopy. The morphological and chemical characterization of chars was performed using SEM-EDS, Raman spectroscopy, XPS, and N2 adsorption/desorption. The catalytic performance and gas composition were investigated by TGA and a fixed-bed reactor during the gasification stage. The results verify that the calcium catalyst reduced the initial gasification temperature of lignite by 150 °C, resulting in a 13.91% increase in the H2 concentration of the synthesis gas and an improvement of the H2/CO ratio to 20.96. The active Ca-C site and intermediate Ca-O-C formed during the co-pyrolysis stage increase the defect density of char, and the transformation of organic calcium species catalyzes the gasification of lignite. The enhanced concentration of H2 in the syngas can be attributed to the catalytic effect of CaO on the water–gas shift reaction during the gasification process. These results are expected to guide efforts in supporting catalytic conversion processes and promoting the efficient utilization of low-rank coal.

Mitochondrial uncoupling caused by a wide variety of protonophores is differently sensitive to carboxyatractyloside in rat heart and liver mitochondria

Mitochondrial uncoupling by small-molecule protonophores is generally accepted to proceed via transmembrane proton shuttling. The idea of facilitating this process by the adenine nucleotide translocase ANT originated primarily from the partial reversal of the DNP-induced mitochondrial uncoupling by the ANT inhibitor carboxyatractyloside (CATR). Recently, the sensitivity to CATR was also observed for the action of such potent OxPhos uncouplers as BAM15, SF6847, FCCP and niclosamide. Here, we report measurements of the CATR effect on the activity of a large number of conventional and novel uncouplers in isolated mammalian mitochondria. Despite the broad variety of chemical structures, CATR attenuated the uncoupling efficacy of all the anionic protonophores in rat heart mitochondria with high abundance of ANT, whereas the effect was much less pronounced or even absent, e.g. for SF6847, in rat liver mitochondria with low ANT content. The fact that the uncoupling action is tissue specific for a broad spectrum of anionic protonophores is highlighted here for the first time. Only with the cationic uncoupler ellipticine and the channel-forming peptide gramicidin A, no sensitivity to CATR was found even in rat heart mitochondria. By contrast, with the recently described ester-stabilized ylidic protonophores [Kirsanov et al. Bioelectrochemistry 2023], the stimulating effect of CATR was discovered both in liver and heart mitochondria.

Bridging pyrimidine hemicurcumin and Cisplatin: Synthesis, coordination chemistry, and in vitro activity assessment of a novel Pt(II) complex

In the upcoming decades, the incidence and mortality rates of cancer are expected to rise globally, with colorectal and prostate cancers among the most prevalent types. Despite advancements in molecular targeted therapy, platinum-based chemotherapies remain the cornerstone of treatment, especially for colorectal and prostate cancer, with oxaliplatin and cisplatin being extremely effective due to their DNA-targeting capabilities. In our pursuit of new platinum-based chemotherapeutics that are potentially less toxic and more effective, we have explored the combination of the Pt-binding groups of the diaminocyclohexane ring used in oxaliplatin, with the stable amino-pyrimidine hemicurcumin moiety. This new derivative exhibit improved stability in physiological conditions and increased solubility in aqueous media, demonstrating promising effects on cell proliferation of both colorectal and prostate cells. We report herein the complete synthesis and chemical characterization in solution of the new derivative [(1R,2R)-N1-(3-(4-((E)-2-(2-Amino-6-methylpyrimidin-4-yl)vinyl)-2-methoxyphenoxy) propyl) cyclohexane-1,2-diamine] (MPYD). Our analysis includes an examination of its acid-base equilibria, speciation and stability in physiological conditions. The synthesis and in situ formation of Pt(II) complexes were investigated by nuclear magnetic resonance spectroscopy, while density functional theory calculations were employed to elucidate the chemical structure in solution. Results on the biological activity were obtained through cell viability assays on different colorectal and prostate cell lines (HCT116, HT29, PC3 and LNCaP).

Promoted electrochemical performance by MOF on MOF composite catalyst of microbial fuel cell: CuCo-MOF@ZIF-8 and the comparison between two-step hydrothermal method and dual-solution method

The microbial fuel cell (MFC) is a device that simultaneously achieves electricity generation and sewage degradation. In this study, a novel cathode catalyst metal-organic frameworks (MOFs) have been fabricated by two-step hydrothermal and dual-solution method (CuCo-MOF@ZIF-8). The synthesized trimetal MOFs exhibited a 3D badminton-like structure morphology and porosity. The results of the characterizations showed that CuCo-MOF@ZIF-8 possesses greater surface area porosity and novel functional groups. The Trimetal MOF-on-MOF mode not only demonstrated the stability of the structure but also enhanced its mechanism. Molecular mechanism analysis revealed changes in the organic ligand and metal binding site due to the transformation of Cu2+ to Cu+, Co2+ to Co3+, and Zn–N to Zn–O organic connection. Furthermore, differences between the two fabrication methods were compared. The solid-state single preparation (CuCo-MOF@ZIF-8-1), was synthesized using the two-step hydrothermal method; the liquid mixed preparation material (CuCo-MOF@ZIF-8-2), was synthesized using the dual-solution method; they exhibited completely different chemical structures and morphologies during material testing and characterization. The maximum output power density of CuCo-MOF@ZIF-8-2-MFC was 246.38 mW/m2, about 2.49 times of ZIF-8 (98.72 mW/m2). The output voltage of CuCo-MOF@ZIF-8-1-MFC was measured at 357 mV over 10 d, while that of CuCo-MOF@ZIF-8-2-MFC reached 365 mV over 12 d.

Zn-MOF-5-Modified biochar derived from KMnO4-activated waste corncob for enhanced adsorption of gaseous ammonia

Ammonia (NH3) is an odor gas pollutant which has serious harm to the environment and human health. The development of advanced adsorbents to remove NH3 is of great significance. Herein, a new adsorbent for NH3 adsorption with high efficiency was prepared by in-situ growth of Zn-MOF-5 on the KMnO4-activated waste corncob-derived porous biochar (KCB). The optimized M0.6K0.1CB-400 sample was obtained by optimizing the mass ratio of KMnO4 to corncob at 0.1, activation temperature at 400 °C, and the dosage ratio of Zn-MOF-5 to porous biochar at 0.6. The M0.6K0.1CB-400 demonstrated an excellent NH3 adsorption capacity of 6.88 mmol/g at 298.15 K and 1 bar, exhibiting a fast adsorption kinetics with 94 % of the equilibrium adsorption capacity reached in just 10 min. The M0.6K0.1CB-400 composite demonstrated good regeneration functionality by maintaining a NH3 removal capacity of 3.44 mmol/g after 6 regeneration cycles. Based on the thermodynamic and kinetic analyses, along with characterization of the chemical composition and physical structure of the NH3-adsorbed samples, the adsorption process of MKCB on NH3 was proven to involve a combination of physical and chemical adsorption. This study introduces a novel method for synthesizing MOF-modified biochar as a highly efficient NH3 adsorbent, offering new insights into the underlying mechanisms of gas purification.

Synthesis of Ultrathin FeS Nanosheets via Chemical Vapor Deposition.

Fe-based 2D materials exhibit rich chemical compositions and structures, which may imply many unique physical properties and promising applications. However, achieving controllable preparation of ultrathin non-layered FeS crystal on SiO2/Si substrate remains a challenge. Herein, the influence of temperature and molecular sieves is reported on the synthesis of ultrathin FeS nanosheets with a thickness as low as 2.3nm by molecular sieves-assisted chemical vapor deposition (CVD). The grown FeS nanosheets exhibit a non-layered hexagonal NiAs structure and belong to the P63/mmc space group. The inverted symmetry broken structure is confirmed by the angle-resolved second harmonic generation (SHG) test. In particular, the 2D FeS nanosheets exhibit exceptional metallic behavior, with conductivity up to 1.63 × 106S m-1 at 300K for an 8nm thick sample, which is higher than that of reported 2D metallic materials. This work provides a significant contribution to the synthesis and characterization of 2D non-layered Fe-based materials.

Synthesis and Characterization of Novel Adsorbents Based on Functionalization of Graphene Oxide with Schiff Base and Reduced Schiff Base for Pesticide Removal.

Graphene oxide (GO) nanosheets were functionalized with Schiff base and reduced Schiff base. Covalent and non-covalent functionalized GO nanostructures have been tested for the removal of pesticides with different chemical structures and properties (e.g., Epoxiconazole, Dimethomorph, Cyprodinil, Chlorothalonil, Acetochlor, Trifluralin) from aqueous solutions. The structure and morphology characteristics of the prepared structures were analyzed using techniques such as solid-state nuclear magnetic resonance (SSNMR), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Results of the experiments showed that, although the non-covalent functionalization did not affect the adsorption properties of GO much, the covalent functionalization increased the adsorption capacity of GO against the mentioned pesticides.

Development of chemical categories for per- and polyfluoroalkyl substances (PFAS) and the proof-of-concept approach to the identification of potential candidates for tiered toxicological testing and human health assessment

Per- and Polyfluoroalkyl substances (PFAS) are a class of manufactured chemicals that are in widespread use and many present concerns for persistence, bioaccumulation and toxicity. Whilst a handful of PFAS have been characterized for their hazard profiles, the vast majority have not been extensively studied. Herein, a chemical category approach was developed and applied to PFAS that could be readily characterized by a chemical structure. The PFAS definition as described in the Toxic Substances Control Act (TSCA) section 8(a)(7) rule was applied to the Distributed Structure-Searchable Toxicity (DSSTox) database to retrieve an initial list of 13,054 PFAS. Plausible degradation products from the 563 PFAS on the non-confidential TSCA Inventory were simulated using the Catalogic expert system, and the unique predicted PFAS degradants (2484) that conformed to the same PFAS definition were added to the list resulting in a set of 15,538 PFAS. Each PFAS was then assigned into a primary category using Organisation for Economic Co-operation and Development (OECD) structure-based classifications. The primary categories were subdivided into secondary categories based on a chain length threshold (>=7 vs < 7). Secondary categories were subcategorized using chemical fingerprints to achieve a balance between total number of structural categories vs.level of structural similarity within a category based on the Jaccard index. A set of 128 terminal structural categories were derived from which a subset of representative candidates could be proposed for potential data collection, considering the sparsity of relevant toxicity data within each category, presence on environmental monitoring lists, and the ability to identify plausible manufacturers/importers. Refinements to the approach taking into consideration ways in which the categories could be updated by mechanistic data and physicochemical property information are also described. This categorization approach may be used to form the basis of identifying candidates for data collection with related applications in QSAR development, read-across and hazard assessment.

Construction of zwitterionic surface of PVDF hollow fiber membrane and the study on the mechanism of “autonomy-response” synergistic enhancement anti-fouling

In this study, polyvinylidene fluoride (PVDF)/styryl maleic anhydride (SMA) hollow fiber membrane was fabricated using the Thermally Induced Phase Separation (TIPS) technique. Subsequently, zwitterion-sulfobetaine methacrylate (SBMA) was introduced to the membrane surface through a Michael addition reaction to create a nearly electrically neutral membrane surface. This modification effectively mitigated the high adsorption of differently charged protein pollutants on the membrane surface, thereby enhancing its anti-fouling performance. Simultaneously, the membrane surfaces with positive and negative charges were separately constructed, and the impact of membrane surface charge properties on the anti-fouling performance against positively and negatively charged foulants was investigated. Furthermore, detailed studies were conducted on the chemical structure, surface morphology, performance, and anti-fouling mechanism of the modified membranes. The results indicate that the electrically neutral membrane modified by zwitterionic SBMA exhibited excellent anti-fouling properties against both bovine serum albumin (BSA) and lysozyme (LYZ), with a flux recovery rate (FRR) reaching 96.5 % and 94.6 %, respectively. The static adsorption capacities of BSA and LYZ on the membrane surface decreased to 5.89 μg cm−2 and 9.53 μg cm−2, respectively. Furthermore, the study investigated the structure of the hydration layer formed by zwitterionic SBMA on the membrane surface, as well as its hydration capacity and anti-fouling mechanism. Subsequently, through an assessment of the long-term stability of the modified membrane and its flux recovery rate (FRR), in conjunction with theories related to hydration layers and thermodynamics, it elucidated the anti-fouling mechanism involving “autonomy-response” synergistic enhancement of zwitterions. These findings will offer new strategies for researching hollow fiber membranes with superior anti-fouling properties and for applying zwitterions in membrane technology.

PH and potential-controlled multi-modal mass transport in block copolymer nanochannel membranes

Inspired by the hydrophobic gating for achieving fast and selective ion/molecular transport in cell membranes, wetting/dewetting transition in solid-state nanopores controlled by external stimuli such as voltage, pH, electrostatics, and light have attracted increasing attention. For an accurate and better understanding, a single nanopore or low-density array of nanopores was preferred to investigate the wetting and dewetting transitions owing to their well-defined chemical functions and physical structures. However, high-density nanochannel membranes capable of processing high-throughput and multi-modal mass transport are more beneficial with the aim of practical use. In this regard, pH- and potential-responsive nanochannel membranes consisting of a polystyrene-b-poly(4-vinylpyridine) (PS-b-P4VP) block copolymer (BCP) are prepared to demonstrate a multi-modal transport system with high-throughput capability. At pH < pKa(P4VP) (pKa ∼ 4.8), the cylindrical P4VP nanodomains are hydrophilic and positively charged, acting as an anion-exchange membrane. In contrast, at pH > pKa(P4VP), the P4VP domains switch to be charge-neutral and hydrophobic, naturally blocking the mass transport through the nanochannels. Applying a sufficiently positive potential to a BCP membrane-coated electrode may induce oxidative wetting in the hydrophobic nanochannels to facilitate mass transport across the membrane with no charge-selectivity. Releasing the bias makes the hydrophobic nanochannel membranes retrieve the original dewetted state, blocking the transport again. In addition, direct observation of the wetting-dewetting transition dynamics in the hydrophobic nanochannels is investigated by monitoring potential-correlated electrochemiluminescence (ECL) signals arising from Ru(bpy)32+ and co-reactant tripropylamine (TPA) under potential modulations. ECL signals tend to decrease with increasing membrane thickness ranging from 0 nm to 820 nm because it requires higher potentials to induce wetting in the nanochannels due to elongated hydrophobic nanochannels. The multi-modal transport system developed in the present work will be useful for applications such as water treatment, biosensors, and smart valve systems like controlled drug release/delivery.

The Potential Health Benefits of Gallic Acid: Therapeutic and Food Applications.

Gallic acid (GA), a phenolic acid found in fruits and vegetables, has been consumed by humans for centuries. Its extensive health benefits, such as antimicrobial, antioxidant, anticancer, anti-inflammatory, and antiviral properties, have been well-documented. GA's potent antioxidant capabilities enable it to neutralize free radicals, reduce oxidative stress, and protect cells from damage. Additionally, GA exerts anti-inflammatory effects by inhibiting inflammatory cytokines and enzymes, making it a potential therapeutic agent for inflammatory diseases. It also demonstrates anticancer properties by inhibiting cancer cell growth and promoting apoptosis. Furthermore, GA offers cardiovascular benefits, such as lowering blood pressure, decreasing cholesterol, and enhancing endothelial function, which may aid in the prevention and management of cardiovascular diseases. This review covers the chemical structure, sources, identification and quantification methods, and biological and therapeutic properties of GA, along with its applications in food. As research progresses, the future for GA appears promising, with potential uses in functional foods, pharmaceuticals, and nutraceuticals aimed at improving overall health and preventing disease. However, ongoing research and innovation are necessary to fully understand its functional benefits, address current challenges, and establish GA as a mainstay in therapeutic and nutritional interventions.

Experimental investigation of kerogen structure and heterogeneity during pyrolysis

Kerogen in shale microstructure plays a vital role in hydrocarbon generation, retention and accumulation. However, characterization of kerogen structure is challenging arguably due to a complex microporous structure and chemical heterogeneity. Thus, the role of kerogen molecular structure in controlling porosity and its heterogeneity, as well as its evolutionary processes, remains unclear. In this study, we investigate the chemical and pore structure of heated kerogen samples by employing a range of characterization tools including gas adsorption experiments, high-resolution transmission electron microscopy (HRTEM), Fourier transform infrared (FTIR) spectroscopy, and laser Raman experiments for a broad range of pyrolysis temperatures (420–850 °C). Multifractal theory and peak fitting techniques were used to evaluate the controlling mechanisms of kerogen pore structure and heterogeneity. The results suggest that with increasing thermal maturity, the content of oxygen functional groups and long-chain aliphatic groups in kerogen significantly decreases, while the length of aromatic fringes increases and gradually becomes oriented. Furthermore, with increasing thermal maturity, the pore volume of kerogen exhibits a non-monotonic trend, i.e., a decrease, followed by an increase, and then finally a decrease. This is primarily influenced by processes such as hydrocarbon production weakening, secondary hydrocarbon cracking, and carbonization. The heterogeneity and dispersion of meso to macro-sized pores in kerogen increase with temperature, while the connectivity gradually decreases. The chemical structure and spatial distribution of kerogen significantly affect the heterogeneity, connectivity, and dispersion of meso to macro-sized pores. Specifically, high aromaticity, structural disorder, and short aliphatic chains result in enhanced heterogeneity and dispersion of meso to macro-sized pores, reducing pore connectivity. This study thus contributes to a deeper understanding of the evolution of organic matter pores.

Combined effects of organic solvent and ultrasonic pretreatments on cellulose fiber extraction from hemp

Extracting pure cellulose fibers from hemp bast for potential textile industry applications requires the removal of non-cellulosic gummy materials. However, traditional degumming methods are largely limited because of the long procedure time, high energy consumption, heavy environmental pollution and insufficient efficiency. Organic solvents have been proved to be an innovative method for lignocellulose extraction. Herein, ethylene glycol solvent combined ultrasonic pretreatment was explored to degum hemp fibers without any further treatment. The purified hemp fibers were systematically characterized using analytical test techniques. Results revealed that the combined degumming could effectively remove non-cellulosic components without damaging the cellulose, and reducing the reaction temperature by 10 ℃ for reaction process. Comparing to the traditional method, the fibers by ultrasonic pretreatment-ethylene glycol process had superior average yield of 68.32 %, higher thermal stability (maximum degradation temperature reached 395 ℃), higher breaking tenacity of 6.13 cN/dtex, higher crystallinity of 78 % and the cellulose content of over 91 %. Moreover, the degumming time and chemical usage were reduced to 40 % and 51.8 %, respectively. Besides, the changes of fibers chemical structure were further investigated and verified by FTIR, EDS, and 13C NMR analysis. Featured with less chemical and energy consumption, eco-friendly and short time-consuming, this treatment has a broad application scope for hemp cellulose fiber extraction.

Fabrication of self-N-doped porous biochar by synergistic pyrolysis activation for efficient tetracycline and CO2 adsorption

The development of green and economical adsorption materials with high pollutant adsorption performance is of great significance to meet environmental challenges. Herein, self N-doped porous carbon materials with excellent tetracycline and CO2 adsorption properties are successfully prepared by synergistic pyrolysis activation of corn stalk and Chlorella mixture. The addition of N-riched Chlorella significantly affects the nanopore and surface chemical structure of biochar, forming rich micro-mesopores, changing the intrinsic N doping form and surface oxygen-containing functional groups. An ultra-high tetracycline adsorption capacity of 1159.7 mg/g can be achieved by using the prepared KBC-3:1 as an adsorbent. A series of kinetic isothermal adsorption models, thermodynamic calculations, as well as comparative characterization analysis show that multiple adsorption mechanisms coexist. The pore filling of micro-mesopores (1.5–3 nm), π-π interactions of CC bonds, H bonding interactions of CO and the strong electrophilicity of pyrrolic N contribute to the excellent tetracycline adsorption performance of KBC-3:1. Furthermore, the material shows great resistance to cationic (K+, Mg2+, Cu2+) interference and excellent cycling performance. In addition, KBC-3:1 also exhibits excellent adsorption capacity for CO2, and the adsorption capacity of 5.21 mmol/g can be achieved at 273 K and 1 bar, which could be attributed to the synergistic activation effect leading to KBC-3:1 having the most abundant pyrrolic and pyridinic N species as well as the rich microporous structure. This work can provide guidance for the development of green and economical high performance carbon materials based on the intrinsic characteristics of biomass.

Revealing the intensification effect of circulating hydrothermal pretreatment: A sustainable route for biorefinery

Hydrothermal pretreatment (HTP) has received huge progress in converting biomass waste into available products at a large scale, but challenges in massive water input and wastewater output still block sustainable biorefinery future. Herein, a circulating hydrothermal technique was proposed by reusing the process wastewater into the next HTP process to enhance energy efficiency and suppress the environmental burdens. During hydrothermal liquid (HL) recycling, the variation of lignin chemical structure, cellulose accessibility, and soluble components were investigated for an in-depth understanding of what happened to lignocellulose. An enhanced hemicellulose dissolution (from 78.1 % to ∼ 85 %) was achieved by the aqueous phase recycling. The reactions of dehydration and polymerization occurred during the circulating HTP process, which contributed to the generation of pseudo-lignin on the cellulose surface, causing a slight weakening of cellulose accessibility. Meanwhile, the organic acid-catalyzed hydrothermal process can facilitate the cleavage of lignin β-O-4 ether linkage and condensation reaction, endowing its potential amphiphilic properties. An in-depth analysis of the evolution of HL components substantiated the potential intensification effect on biomass deconstruction by the generation of hemicellulose-derived organic acids. Life cycle assessment revealed that the circulating HTP technique resulted in about a 29 % reduction in primary energy depletion and an order of magnitude reduction in CO2 emissions as opposed to that of the conventional one. This work unveils the structure evolutions of lignocellulose clearly during the HL recycled process, and also highlights a feasible route for the sustainable biorefinery.

Penicillides from Penicillium and Talaromyces: Chemical Structures, Occurrence and Bioactivities.

Penicillide is the founder product of a class of natural products of fungal origin. Although this compound and its analogues have been identified from taxonomically heterogeneous fungi, they are most frequently and typically reported from the species of Talaromyces and Penicillium. The producing strains have been isolated in various ecological contexts, with a notable proportion of endophytes. The occurrence of penicillides in these plant associates may be indicative of a possible role in defensive mutualism based on their bioactive properties, which are also reviewed in this paper. The interesting finding of penicillides in fruits and seeds of Phyllanthus emblica is introductory to a new ground of investigation in view of assessing whether they are produced by the plant directly or as a result of the biosynthetic capacities of some endophytic associates.