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The objective of the present investigation was to extract pectic polysaccharides from sesame seed hull and to determine their physicochemical and functional characteristics. The pectic polysaccharides in the seed hull were extracted with HCl and then collected at three ethanol concentrations of 30% (SSP30), 50% (SSP50), and 90% (SSP90). We found that SSP30 represented 75.6% of the total polysaccharides, and that it contained 76.39% galacturonic acid, with many HG domains and few short side chains in the RG-I domains. SSP30 exhibited the strongest hydroxyl radical scavenging activity among the three fractions, and was better able to stabilize the emulsions. Higher Mw pectic polysaccharides were firstly precipitated at lower ethanol concentrations, and the Mw of the precipitated pectic polysaccharides decreased with increasing ethanol concentration. These results provide important information on the structure and functional characteristics of sesame hull polysaccharides. This information can contribute to the future development of sesame hull polysaccharides for industrial purposes.

Edible oil is prone to be contaminated by Benzo[a]pyrene (BaP) during production and processing. Adsorption is an important technology for the removal of BaP from edible oil, and biochar as a new type of adsorbent for the treatment BaP has received extensive attention. In this study, we prepared unmodified biochar and ZnCl2-modified biochar from sesame straw cellulose (SSB and SSZ) and sesame capsule cellulose (SCB and SCZ), carried out structure characterization by Fourier Transform Infrared (FT-IR), Brunauer-Emmett-Teller (BET) and Scanning Electron Microscope (SEM), and finally evaluated their potential effectiveness in BaP removal from sesame oil. FT-IR results revealed that SSZ and SCZ showed higher peak intensities, indicating that they could provide more active sites for adsorption. The results of XRD presented that SSZ and SCZ had a higher graphitization degree than the unmodified biochar. SEM results showed that the SSZ and SCZ had more complex pore structure, which is beneficial to adsorption. BET analysis results showed that SSZ and SCZ have a higher specific surface area of 1622.83–1797.39 m2/g and a better developed porous structure (the total pore volume Vtotal is 0.9434–1.0023 cm3/g) than the SSB and SCB (specific surface area is 350.55–352.59 m2/g, and Vtotal is 0.1907–0.1918 cm3/g), indicating that modification promotes the formation of porous structure and thus improves the adsorption capacity of biochar. Adsorption experiments confirmed once again that the BaP removal rates (92.67%–96.13%) of SSZ and SCZ were much higher than that of unmodified biochar (3.34%–4.28%), and the BaP content in the sesame oil treated by SSZ and SCZ were far below the current EU maximum levels (2 μg/kg). Therefore, the modified biochar from cellulose is a promising adsorbent for BaP removal. In future studies, the influences of bichar on the nutritional quality of edible oil should be taken into consideration so as to find an ideal active carbon substitute for BaP removal in edible oil.

Chinese quince (Chaenomeles sinensis) fruits offer a potential source of pectin and hemicellulose. However, the existence of lignin-carbohydrate complexes (LCCs) can negatively impact the extraction of pectin and hemicellulose. In this work, LCCs were sequentially fractionated from Chinese quince during the removal of pectin and hemicellulose. The structures of LCCs were characterized by HPAEC, FT-IR, GPC, Py-GC/MS, TGA and 2D HSQC NMR. The results showed that the carbohydrate content and molecular weight of LCCs was found to be changed significantly after the removal of hemicellulose (KSH). The lignin in Björkman LCCs was found to be linked mainly to galactan and fructan, whereas the lignin LCC-AcOHs was found to be linked mainly to arabinan after the removal of KSH. The isolation of carbonate-soluble pectin (NSP) increased thermal stability of Björkman LCC fraction, however, the isolation of chelator-soluble pectin (CSP) increased the thermal stability of LCC-AcOHs. The S/G ratios of LCC-AcOHs increased and large amounts of S-type lignin released during sequential fractionation of pectin and hemicellulose. These results will be beneficial for understanding the mechanisms of pectin and hemicellulose isolation, thereby facilitating the potential application of Chinese quince as a valuable natural resource for food and other industries.

As the only ribosomally encoded N-substituted amino acid, proline promotes distinct secondary protein structures. The high proline content in collagen, the most abundant protein in the human body, is crucial to forming its hallmark structure: the triple-helix. For over five decades, proline has been considered compulsory for synthetic designs aimed at recapitulating collagen's structure and properties. Here we describe that N-substituted glycines (N-glys), also known as peptoid residues, exhibit a general triple-helical propensity similar to or greater than proline, enabling synthesis of stable triple-helical collagen mimetic peptides (CMPs) with unprecedented side chain diversity. Supported by atomic-resolution crystal structures as well as circular dichroism and computational characterizations spanning over 30 N-gly-containing CMPs, we discovered that N-glys stabilize the triple-helix primarily by sterically preorganizing individual chains into the polyproline-II helix. We demonstrated that N-glys with exotic side chains including a "click"-able alkyne and a photosensitive side chain enable CMPs for functional applications including the spatiotemporal control of cell adhesion and migration. The structural principles uncovered in this study open up opportunities for a new generation of collagen-mimetic therapeutics and materials.

Chinese quince is one kind of crop that has edibility and historical medical applications. However, the high amount of lignin makes processing Chinese quince fruit difficult; on the other hand, this lignin represents a valuable resource if a way of using it in industrial applications could be found. In this study, the structural features and antioxidant activities of Brauns native lignin (BNL) isolated from Chinese quince fruit after oven drying (60 °C, 75 °C, and 90 °C), sun drying, freeze-drying, and subcritical dimethyl ether drying were assessed. The BNL samples had low molecular weights (Mw, 2604–5511 g/mol), high carbohydrate content (6.10–9.95 %), and high phenolic OH content (1.76–2.29 mmol/g). NMR spectra showed that the BNL is of the SGH-type with the relative content of p-hydroxyphenyl units ranging from 13 to 21 %. Oven drying (90 °C) reduced the carbohydrate content and increased the phenolic hydroxyl content. Freeze-drying reduced the relative content of β-O-4′ linkages and increased the H-unit content. In terms of antioxidant activities, all samples possessed high DPPH free radical scavenging capacity (IC50, 0.12−0.22 mg/mL) and strong reducing power. These results indicate that BNL extracted from Chinese quince fruit is a promising source of natural antioxidant and biomass material.

Yufei Feng,1 Guozhao Qin,1 Shuyuan Chang,1 Zhongxu Jing,2 Yanyan Zhang,1 Yanhong Wang1 1Key Laboratory of Chinese Materia Medica in Ministry of Education, Heilongjiang University of Chinese Medicine, Harbin, Heilongjiang, People’s Republic of China; 2Heilongjiang Provincial Administration of Traditional Chinese Medicine, Harbin, Heilongjiang, People’s Republic of ChinaCorrespondence: Yanhong Wang Tel +86451-87266893Email 799378826@qq.comIntroduction: Hyperoside (HYP), a flavonol glycoside compound, has been shown to significantly inhibit the proliferation of malignant tumors. Mitochondria serve as both “energy factories” and “suicide weapon stores” of cells. Targeted delivery of cytotoxic drugs to the mitochondria of tumor cells and tumor vascular cells is a promising strategy to improve the efficacy of chemotherapy.Objective: We report a novel dual-functional liposome system possessing both extracellular charge reversal and mitochondrial targeting properties to enhance drug accumulation in mitochondria and trigger apoptosis of cancer cells.Methods: L-lysine was used as a linker to connect 2,3-dimethylmaleic anhydride (DMA) and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE) to yield a new compound, DSPE-Lys-DMA (DLD). Then, DLD was mixed with other commercially available lipids to form charge reversed and mitochondria-targeted liposomes (DLD-Lip). The size, morphology, zeta potential, serum stability, and protein adsorption of the HYP loaded DLD-Lip (HYP/DLD-Lip) were measured. The release profile, cellular uptake, in vitro and in vivo toxicity, and anticancer activity of HYP/DLD-Lip were investigated.Results: The results showed that the mean diameter of the liposomes was less than 200 nm. The zeta potential of the liposomes was negative at pH 7.4. However, the zeta potential was positive at weak acidic pH values with the cleavage of the DMA amide. The charge reversion of HYP/DLD-Lip facilitated the cellular internalization and mitochondrial accumulation for enhanced antitumor effect. The strongest tumor growth inhibition (TGI 88.79%) without systemic toxicity was observed in DLD/HYP-Lips-treated CBRH-7919 tumor xenograft BALB/C mice.Conclusion: The charge reversed and mitochondria-targeted liposomes represented a promising anticancer drug delivery system for enhanced anticancer therapeutic efficacy.Keywords: mitochondria-targeted, liposome, charge reversal, antitumor, hyperoside

Lignin from the Chinese quince (Chaenomeles sinensis) fruit offers a promising source of natural antioxidant for industrial applications. However, the utilization of Chinese quince fruit lignin is restricted by its inhomogeneous nature. Accordingly, Chinese quince fruit lignin was sequentially fractionated with organic solvents of increasing dissolving capacity to prepare homogeneous lignin fractions. The GPC (gel permeation chromatography) results showed that the molecular weights of lignin fractions increased from dichloromethane fraction to dioxane/water fraction. The five lignin fractions were also compared with respect to yield, carbohydrate content, thermal stability, inter-unit linkages, S/G ratios, and phenolic OH content. Among the five fractions, the ethyl acetate fraction showed a lower proportion of β-O-4′ linkages (48.4%), the highest thermal stability, the highest phenolic OH content (2.8 mmol/g), and the highest DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging index and reducing power. The high antioxidant performance of the ethyl acetate fraction implies that it can be used as a natural antioxidant. This study shows that sequential solvent fractionation of lignin can produce homogeneous fractions with enhanced antioxidant performance. In addition, it demonstrates that Chinese quince fruits are a potentially valuable natural resource.

Acetic acid at atmospheric pressure is an alternative solvent that can be used for high-efficiency separation of lignin. However, few studies reported the isolation of lignin using acetic acid at above atmospheric pressure. In this study, acetic acid solution at above atmospheric pressure was used to extract lignin from Chinese quince fruit. The influences of different extraction conditions on the lignin yields were firstly investigated. Among the five extraction parameters (extraction temperature/pressure, acetic acid concentration, extraction time, catalyst dosage, and solid/liquid ratio), catalyst dosage had the most important influence on lignin yields. Five acetic acid lignin (AAL80, AAL100, AAL120, AAL140, and AAL160) samples obtained at different extraction temperatures/pressures (80 °C–160 °C/0.03–0.35 MPa) were used to analyze the influence of extraction temperatures/pressures on their structural features. Comparing to lignins extracted with acetic acid at atmospheric pressure, lignins obtained by acetic acid extraction at above atmospheric pressures (AAL120, AAL140, and AAL160) had higher purity. The acetic acid could degrade lignin at temperatures above 120 °C. When extracted at 120 °C–160 °C, the depolymerization degree of lignins increased with rising temperatures. AAL160 with more condensed structures was the most thermally stable. As the extraction temperature rose, the proportion of β–5 linkages in lignins gradually increased, while the proportion of β–O–4 and β–β linkages decreased. AAL80 had the highest DPPH, while AAL120 showed the highest ferric reducing activity. The study clarifies the lignins isolated with acetic acid at above atmospheric pressure from Chinese quince fruits and contributes to their potential application.

Natural biocompatible materials such as self-assembled natural small molecule products (NSMP) with anticancer activity are of increasing interest for synergistic biomedical applications. Herein, we discovered and developed four new self-assembled tricyclic diterpene acids NSMP with favorable anticancer activity for synergistic and safe antitumor chemotherapy, including dehydroabietic acid, 15-hydroxy-dehydroabietic acid, abietic acid, and 12-hydroxyabietic acid. The self-assembled performance and mechanism of these four compounds with different morphologies were explored in detail by molecular dynamics simulation, and revealed the coplanarity and orderliness of molecular arrangements which are speculated to be responsible for the self-assembly into spheres or rods. The screened and optimized abietic acid (AA) was chosen to prepare the synergistic antitumor drug AA-PTX NPs by co-administration with paclitaxel through multiple hydrogen bonds. The resulting nanodrugs were internalized into cells through a lysosome acidification uptake pathway. The improved water-solubility, significantly enhanced in vitro cytotoxicity, and excellent biosafety, lead to a highly efficient and safe in vivo anticancer efficacy of 81.2% inhibition rate with only three doses. This work provides new insights to explore the self-assembly behavior of small molecules and broadens the types of self-assembled active NSMP, providing a promising perspective for the fabrication of active NSMP mediated medical agents for multiple synergistic therapies.

A novel tannic acid-immobilized chitosan resin (TICR) was prepared by Mannich reaction for the adsorption of proteins. The physical properties of TICR were characterized and the effects of contact time, pH, and initial concentration of (bovine serum albumin) BSA on its adsorption by TICR were investigated. The Langmuir isotherm model was applied to describe the adsorption isotherm. The equilibrium data are fitted to the Langmuir isotherm model. The maximum monolayer BSA adsorption capacities of TICR were found to be 1.094, 1.487, and 1.694 mg/g at 298, 308, and 318 K, respectively. Furthermore, the data were analyzed on the basis of pseudo-first order, pseudo-second order, and intraparticle diffusion models. The correlation results suggested that the pseudo-second order model fitted the experimental data very well. The thermodynamic study indicated that the adsorption process of BSA onto TICR was endothermic, and the Gibbs free energy (ΔGo), enthalpy (ΔHo), and entropy (ΔSo) of the adsorption process were calculated according adsorption isotherm data. TICR could be reused for 10 times with only 19 % loss of adsorption capacity for BSA.

We report a first attempt to investigate the reaction mechanisms of hydroborate iron compound (HIC), a promising candidate for combustion catalyst, in AP/HTPB/Al composite solid propellants using ammonium perchlorate (AP) as the oxidizer and aluminum as the metal fuel. The effects of HIC on the combustion properties of propellants were experimentally examined to determine burning rates, combustion flame structures and flame temperature distribution. The combustion residues were collected and examined; the mechanical sensitivity of propellant samples were tested. It was found that the addition of HIC particles can increase the burning rates with only minor changes of the pressure exponent. When 5.0 wt% of Al is replaced by HIC, the pressure exponent increases from 0.31 to 0.35 over the pressure range 1–12 MPa while the burning rate increases from 33 mm s−1 to 40 mm s−1 at 7 MPa. The combustion flame images of burning propellants surface loaded with HIC at various pressures present multi-flame structures, and the flame brightness increases with increasing the pressure. Many sparks are observed near the burning surface during the propellant combustion, due to burning aluminum particles in gas phase. With 5.0 wt% HIC included, the propellant produces very different condensed combustion products (CCPs) with a variety of morphologies, and the most typical ones are “porous” shape, large alveolate and loose structures. The relative combustion residue mass decreases with increasing pressure (1–5 MPa) and HIC mass fraction in the formulation (0–5%); While HIC powder is insensitive to friction and impact stimuli (0% at height is higher than 125 cm), the tested propellant formulations containing different mass fraction of HIC particles result sensitive to impact and friction a bit more than the reference formulation without HIC particles.

Selenium (Se) is a trace mineral element in soils that can be beneficial to plants in small amounts. Although maize is among the most economically important crops, there are few reports on the effects of Se on maize seedling growth at the molecular level. In this study, the growth of maize seedlings treated with different concentrations of Na2SeO3 was investigated, and the physiological characteristics were measured. Compared with the control, a low Se concentration promoted seedling growth, whereas a high Se concentration inhibited it. To illustrate the transcriptional effects of Se on maize seedling growth, samples from control plants and those treated with low or high concentrations of Se were subjected to RNA sequencing. The differentially expressed gene (DEG) analysis revealed that there were 239 upregulated and 106 downregulated genes in the low Se treatment groups, while there were 845 upregulated and 1,686 downregulated DEGs in the high Se treatment groups. Both the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation analyses showed a low concentration of the Se-stimulated expression of “DNA replication” and “glutathione (GSH) metabolism”-related genes. A high concentration of Se repressed the expression of auxin signal transduction and lignin biosynthesis-related genes. The real-time quantitative reverse transcription PCR (qRT-PCR) results showed that in the low Se treatment, “auxin signal transduction,” “DNA replication,” and lignin biosynthesis-related genes were upregulated 1.4- to 57.68-fold compared to the control, while, in the high Se concentration treatment, auxin signal transduction and lignin biosynthesis-related genes were downregulated 1.6- to 16.23-fold compared to the control. Based on these transcriptional differences and qRT-PCR validation, it was found that a low dosage of Se may promote maize seedling growth but becomes inhibitory to growth at higher concentrations. This study lays a foundation for the mechanisms underlying the effects of Se on maize seedling growth.

The safety problems related to the occurrence of benzo(a)pyrene in edible oil have been a major threat to human health, and now significant attention has been to remove benzo(a)pyrene. So in this work, cellulose, hemicellulose, and lignin biochars were prepared, and then were used to remove benzo(a)pyrene from contaminated oil. Based on the nitrogen adsorption/desorption isotherms and the scanning election micrographs, the modified biochars had a huge specific surface area of 983.50-1915.55 m2/g and a well-developed porous structure. The modified biochars showed higher removal rate for benzo(a)pyrene than unmodified biochars. The highest adsorption (95.79%) of benzo(a)pyrene was achieved using the modified lignin biochar, which was therefore selected for evaluation of adsorptive capacity. The ability of the modified lignin biochar to adsorb benzo(a)pyrene was consistent with the pseudo-second order kinetic equation indicating mainly chemisorption, and it fit the Freundlich isotherm (R2 > 0.999), thereby revealing the occurrence of multilayer adsorption. The effect of π-π conjugation interaction and pore-filling together promoted the high adsorption performance of the modified lignin biochar. This work demonstrates that the modified lignin biochar could be a promising adsorbent for the removal of benzo(a)pyrene from edible oils.

Ammonia is one of the most important industrial chemicals due to its wide application in various fields. However, its synthesis requires heavy energy consumption and harsh reaction conditions. Here...

Designing an efficient membrane for He purification is quite crucial in scientific and industrial applications. Ultrathin membranes with intrinsic pores are highly desirable for gas purification because of their controllable aperture and homogeneous hole distribution. Based on the first-principles density function theory and molecular dynamics simulations, we demonstrate that the compressively strained graphitic carbon nitride (CN) can effectively purify He from Ne and Ar. Under a compressive strain of 6%, the CN monolayer with a suitable pore size presents an easily surmountable barrier for He ( 0.11 eV) but formidable for Ne ( 0.51 eV) and Ar ( 2.45 eV) passing through the membrane, and it exhibits exceptionally high selectivity of 5.17 × 10 6 for He/Ne and 1.89 × 10 39 for He/Ar, as well as excellent He permeance of 1.94 × 10 7 GPU at room temperature, superior to those of porous graphene and C2N membrane. Our results confirm that strain-tuned CN membrane could be potentially utilized for He separating from other noble gases.

Ethnopharmacological relevance Citrus reticulatae Pericarpium (Chen pi) was widely used as an important ingredient in the prescription of TCM to treat phlegm fluid retention type hypertension. Since Chen pi is involved in treatment as antihypertensive TCM formula, we have reasonable expectation in believing that it might possess vasorelaxant activity. Aim of the study This study is designed to investigate the vasorelaxant effect of Chen pi and to study its pharmacology effects. Materials and methods The vasorelaxant effect of water extract of Chen pi (CRW) were evaluated on thoracic aortic rings isolated from Sprague Dawley rats. The fingerprint of Chen pi and the extracts were developed with quantification of hesperidin content by HPTLC. Results CRW exhibited the strongest vasorelaxant activity. CRW caused the relaxation of the phenylephrine pre-contracted aortic rings in the presence and absence of endothelium as well as in potassium chloride pre-contracted endothelium-intact aortic ring. The incubation of propranolol (β-adrenergic receptor blocker), atropine (muscarinic receptor blocker), Nω-nitro- L -arginine methyl ester (NO synthase inhibitor), ODQ (sGC inhibitor), indomethacin (COX inhibitor), 4-aminopyridine (KV blocker), barium chloride (Kir blocker), and glibenclamide (KATP blocker) significantly reduced the vasorelaxant effects of CRW. CRW was also found to be active in reducing Ca2+ releases from the sarcoplasmic reticulum and suppressing the voltage-operated calcium channels. Conclusion The vasorelaxant effect of CRW on rat aorta involves NO/sGC, calcium and potassium channels, muscarinic and β-adrenergic receptors.

It is crucial to enhance anti-oxidation resistance of copper nanowires (Cu NWs) without degrading their transparent conductive characteristics. Here, reduced graphene oxide/copper nanowires (RGO/Cu NWs) with coating nanostructures were synthesized by a facile one-pot hydrothermal method. The copper nanowire was prepared by using copper (I) chloride as the precursor while the graphene oxide (GO) was reduced using the polyols as the reducing agent in order to obtain the coating structure, abandoning conventional tedious multi-step preparation processes. The microstructure and morphology of RGO/Cu NWs were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), selected-area electronic diffraction (SEAD) and X-ray photoelectron spectroscopy (XPS). The as-synthesized RGO/Cu NWs nanostructure is found to be almost coating structure of particle-free, high aspect ratio (L/D≈890) Cu NWs decorated with reduced graphene oxide (RGO), which accounts for the outstanding oxidation resistance. The stability tests show that the sheet resistance (RS) of the RGO/Cu NWs is almost unchanged over 20 days at room temperature or 5 h at 60 °C. What’s more, the sheet resistance of the RGO/Cu NWs with coating structure only increases to 2.48 times after being heated for 150 min at 100 °C, which can directly indicate that the RGO/Cu NWs nanostructure has excellent anti-oxidation resistance and temporal stability. Also, the as-prepared RGO/Cu NWs transparent electrode has both low sheet resistance of 58.36 Ω/sq and high optical transmittance (87.12% @550 nm). The composite materials provide a better strategy to resolve the problem of being easily oxidized for Cu NWs and promote their wide practical applications.

Subcritical water treatment has received considerable attention due to its cost effectiveness and environmentally friendly properties. In this investigation, Chinese quince fruits were submitted to subcritical water treatment (130, 150, and 170 &deg, C), and the influence of treatments on the structure of milled wood lignin (MWL) was evaluated. Structural properties of these lignin samples (UL, L130, L150, and L170) were investigated by high-performance anion exchange chromatography (HPAEC), FT-IR, gel permeation chromatography (GPC), TGA, pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), 2D-Heteronculear Single Quantum Coherence (HSQC) -NMR, and 31P-NMR. The carbohydrate analysis showed that xylose in the samples increased significantly with higher temperature, and according to molecular weight and thermal analysis, the MWLs of the pretreated residues have higher thermal stability with increased molecular weight. The spectra of 2D-NMR and 31P-NMR demonstrated that the chemical linkages in the MWLs were mainly &beta, O-4&prime, ether bonds, &beta, 5&prime, and &beta, &beta, &prime, and the units were principally G- S- H- type with small amounts of ferulic acids, these results are consistent with the results of Py-GC/MS analysis. It is believed that understanding the structural changes in MWL caused by subcritical water treatment will contribute to understanding the mechanism of subcritical water extraction, which in turn will provide a theoretical basis for developing the technology of subcritical water extraction.

Proanthocyanidins (PAs) are polyphenols that are widely distributed in various parts of plants, e.g., fruits, vegetables, nuts, bark, and leaves. PAs can be divided into three classes based on their constitutive units and the linkages between them: procyanidins, prodelphinidins, and propelargonidins. Many studies have demonstrated broad biological activities of proanthocyanidins, including antioxidant, antibacterial, antiviral, anticarcinogenic, and anti-inflammatory activities. Due to their structural diversity and the related physicochemical properties, isolation, and structural analysis of proanthocyanidins are important for their application. New technologies developed during the past decade are currently used for the extraction and structural analysis of proanthocyanidins. In addition to traditional organic solvents, new solvents, such as supercritical and subcritical fluids, ionic liquids, and deep eutectic solvents are used to extract proanthocyanidins. Qualitative and quantitative analysis of proanthocyanidins is a particularly interesting area of research. Several novel analysis methods, such as ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), two-dimensional (2D) NMR, matrix-assisted laser desorption/ionization (MALDI), and Fourier transform ion cyclotron resonance mass spectrometry (FT–ICR–MS) are used for identifying proanthocyanidins. In this chapter, recent advances in the extraction, purification, and structural elucidation of proanthocyanidins are reviewed.

Objective To explore the anaphylaxis effect and anaphylaxis substances of honeysuckle. Methods Rat peritoneal mast cells (PMC) were separated and purified, the cells were incubated with compound 48/80 (0.02 g/L), physiological saline and honeysuckle extract (120 g/L) at 37 °C for 0, 15, 30, 45 and 60 min. Degranulation were observed by optical microscope and transmission electron microscope. Annexin V positive cell rate was detected by flow cytometry to reflect the degranulation rate of PMC. SD rats were supplied with honeysuckle extract by intravenous injection at a dose of 2.25 g/L. After administration, different parameters were analyzed, including the symptoms, histamine (HIS) and tryptase (MCT) levels, which were determined to explore the effect of anaphylaxis. Regression analysis was used to calculate the relationships between the peaks and the pharmacological effects to explore potentially anaphylactoid components. Results The percentage of Annxin V positive cells and the degranulation ratio were markedly elevated in PMC treated with honeysuckle extract for more than 15 min (P Conclusion This study established a prospective method to clarify the anaphylactoid components of honeysuckle extract, which would provide guidance for screening anaphylactoid components in traditional Chinese medicine injections containing honeysuckle in the prescription.

Chinese quince fruits (Chaenomeles sinensis) have an abundance of lignins with antioxidant activities. To facilitate the utilization of Chinese quince fruits, lignin was isolated from it by auto-catalyzed ethanol organosolv pretreatment. The effects of three processing conditions (temperature, time, and ethanol concentration) on yield, structural features and antioxidant activities of the auto-catalyzed ethanol organosolv lignin samples were assessed individually. Results showed the pretreatment temperature was the most significant factor; it affected the molecular weight, S/G ratio, number of β-O-4' linkages, thermal stability, and antioxidant activities of lignin samples. According to the GPC analyses, the molecular weight of lignin samples had a negative correlation with pretreatment temperature. 2D-HSQC NMR and Py-GC/MS results revealed that the S/G ratios of lignin samples increased with temperature, while total phenolic hydroxyl content of lignin samples decreased. The structural characterization clearly indicated that the various pretreatment conditions affected the structures of organosolv lignin, which further resulted in differences in the antioxidant activities of the lignin samples. These results can be helpful for controlling and optimizing delignification during auto-catalyzed ethanol organosolv pretreatment, and they provide theoretical support for the potential applications of Chinese quince fruits lignin as a natural antioxidant in the food industry.

Lignin, as one of the most abundant natural polymer compounds in wood and annual plants, has a complex chemical structure. It is fundamentally an aromatic polymer, composed of many aromatic rings with methoxyl and hydroxyl functional groups. Because of its multifunctional side groups, lignin can act as a free radical scavenger, thus acting as a natural antioxidant agent. However, extraction conditions, source species and structure affect the antioxidant activity of lignins. As a relatively safe and natural antioxidant, lignin can be used in foods, pharmaceuticals, cosmetics, and industrial materials. In this chapter, the correlation of lignin between structural characteristics and its radical scavenging capabilities, the relationship between antioxidant capacity and potential cytotoxicity, and the advances in commercial applications of lignin as an antioxidant were reviewed and analyzed.

Hexanitro complex K2Ba[Ni(NO2)6] was prepared via the co-precipitation method, and its composition and morphology were characterized by XRD, SEM, XPS and FT-IR techniques. The catalytic performances of K2Ba[Ni(NO2)6] for CL-20, FOX-7 and TKX-50 thermolysis were also discussed and studied by using DSC and TG-DTG-MS. After K2Ba[Ni(NO2)6] were mixed with CL-20, the activation energy (Ea) of thermolysis reaction was increased, while the heat release was greatly improved, and the transformation from NH3 to NO occurred. It is attributed to that the decomposition products of K2Ba[Ni(NO2)6] have strong effects on the oxidation of the radicals and the electrons transfer. Besides, the thermolysis Ea of FOX-7 by addition of the K2Ba[Ni(NO2)6] was increased by 81.03 kJ mol−1, and the heat release was greatly increased. In addition to that the two-step separate thermolysis processes of pure FOX-7 was almost replaced by a one-step exothermic reaction for the FOX-7/K2Ba[Ni(NO2)6] mixture, which was due to that Ni2+ cations could effectively increase the activity of amino groups in the FOX-7 thermolysis process. Finally, K2Ba[Ni(NO2)6] scarcely has the thermolysis catalytic activity of TKX-50 owing to the influence of metal cations on the decomposition of the hydroxylamine. Furtherly, the characteristics of ignition and flame propagation on the three energetic mixtures were strongly correlated to their thermolysis pathway and mechanism. The comparative study on the effects of K2Ba[Ni(NO2)6] to the CL-20, FOX-7 and TKX-50 thermolysis and ignition showed that the hexanitro complex has great significance on promoting the heat release efficiency of solid propellants for future study.

Hawk tea, prepared from the young leaves of Litsea coreana Levl. var. lanuginosa, is consumed as a tonic in China. Essential oils (EOs) from Hawk tea collected from six habitats in China were obtained by hydro distillation. Extraction yields ranged from 0.42% (g/g) in samples from Ningguo to 0.11% (g/g) in samples from Qingchuan. A total of 50 compounds in the six EO samples were identified by Gas Chromatography-Mass Spectrometer. The dominant compounds were citral (4.67–21.12%), caryophyllene (2.31–15.74%), dodecanal (2.10–15.38%), α-humulene (1.45–13.56%) and decanal (1.91–13.17%). Altitude may contribute the greatest effect on the chemical variation of the six EO samples. All the EO samples showed bioactivities. Among them, the EOs from the Pingshan sample showed the best ABTS radical scavenging activity (78.67 mg TEs /g) and better antimicrobial activities (MIC = 156.25–625 μg/mL) and had stronger DPPH radical scavenging activity (IC50 = 0.71 mg/mL) than BHT (IC50 = 0.76 mg/mL). The EOs from the Ningguo sample showed the highest reducing power (26.06 mg Fe2+/g) in a FRAP assay, the best inhibitory effect on α-glucosidase (1.71 mg/mL) and was the most cytotoxic (66.03–77.03 μg/mL) in an MTS assay. Therefore, the EOs from Hawk tea could be suitable for commercialization in the food, cosmetic or medical industries. Due to the activities of their EOs, plants growing in Pingshan and Ningguo are the optimal candidates.

The lignin-carbohydrate complexes (LCCs) of the mesocarp (MS) and near the endocarp (NE) of Chinese quince (Chaenomeles sinensis) fruits were analyzed using three different methods of fractioning: milled wood lignin (MWL), LCC extracted from crude MWL with acetic acid (LCC-AcOH), and Bjorkman LCC. The MWL and LCC fractions were characterized by carbohydrate composition analysis, SEC, FT-IR, Py-GC/MS, thermal analysis and 2D HSQC NMR. Notably, large amounts of arabinose and galactose remained in the Björkman LCC fractions suggesting a chemical bond between the lignin and pectin. MWL and LCC-AcOH fractions showed better thermal stability than the Björkman LCC fractions. The structure of MS lignin was similar to that of NE lignin; however, fractions from the different fractionation methods revealed differences. The MWL fractions were rich in benzyl ether and γ-ester linkages, while the Björkman LCC fractions contained phenyl glycoside and γ-ester linkages, and the LCC-AcOH fractions contained phenyl glycoside and benzyl ether linkages. These findings are helpful in understanding the nature of lignin and LCC in Chinese quince fruits and provide a theoretical support for their potential application.

In this study, Fe3O4 magnetic nanoparticles were prepared from FeCl2/FeCl3 and NaOH solution by chemical co-precipitation method in an impinging stream-rotating packed bed. Then, Fe3O4/TiO2 photocatalyst was prepared for photocatalytic degradation of phenol by sol–gel method using butyl titanate and Fe3O4 magnetic nanoparticles. The surface morphology, structure and crystalline phase of Fe3O4/TiO2 were characterized by high resolution transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, vibrating sample magnetometer, dynamic light scattering and ultraviolet–visible spectroscopy. A 100 mg L−1 phenol aqueous solution was used as the pollutant. The effects of calcination temperature, the dosage of butyl titanate, the dosage of catalyst and solution pH value on the photocatalytic activity of Fe3O4/TiO2 were investigated. The results showed that Fe3O4/TiO2 photocatalyst could be easily recovered from the solution by permanent magnet. The photocatalytic activity reached a maximum under the following conditions: calcination temperature, 400 °C; butyl titanate dosage, 10 mL; catalyst dosage, 3 g L−1; and solution pH value, 2.

In this study, three pretreatment processes were evaluated for their effects on the structural features and antioxidant activities of lignins extracted by the acetosolv process from the fruit of Chinese quince. The three pretreatments included dephenolization, sugar removal, and multiple processes (a combination of both dephenolization and sugar removal). The results showed that after sugar removal pretreatment, the carbohydrate content, the molecular weight and S/G value of the lignin fractions decreased. However, after dephenolization pretreatment, the carbohydrate content and the molecular weight of the lignin fractions increased. After sugar removal and dephenolization, there were increases in the temperatures corresponding to the maximal rate of decomposition (DTGmax) in all lignin fractions. The radical scavenging index of lignin after sugar removal pretreatment was higher compared to other pretreatments and no treatment. The results of these tests showed that sugar removal, as a pretreatment, enhanced lignin extraction, yielding pure and highly functional lignins. Additionally, dephenolization or multiple process were beneficial to the acquisition of macromolecular lignins. All the results provided references for the biorefinery of biomass rich in polyphenol and sugar compounds.

Chinese quince seed gum (CQSG) extracted under water-, alkali- and acid- conditions at 25, 50, and 80 °C, were evaluated in terms of yield, monosaccharide composition, molecular distribution, thermal gravimetry, emulsifying stability, rheological properties, and free radical scavenging ability. The results showed that the yield of CQSG increased to 3.9% after water extraction at 80 °C. Alkali and acid treatments promoted the conversion of neutral sugars to the uronic acid branch. Regardless of the extraction temperature, the xylose chain was the main component (35%–40%); however, a reduction was observed as the extraction temperature increased to 80 °C. All CQSG solutions extracted under these isolation conditions exhibited non-Newtonian rheological behavior. Compared to water-extracted samples, the alkali-extracted samples showed the worst thermal stability, while the acid-treated samples showed the worst emulsifying stability. This study provides theoretical support for the potential application of CQSG polysaccharides in the food and pharmaceutical industries.

Making full use of sunflower seeds, including oil and the polysaccharides extracted from the meals which oil has been extracted, is one way to enhance their industrial value. Such meals contain abundant polysaccharides; however, the application of polysaccharides isolated from sunflower remaining meals after oil extraction has not been investigated. In this study, polysaccharides were isolated by alkali from sunflower meals after different oil extraction processes, and their structural properties and antioxidant activities were compared. The results indicated that these polysaccharides displayed significant variability in monosaccharide composition and molecular weight. Differences in structural properties could result in differences in functional antioxidant properties. The polysaccharide (SPHE-1) obtained from the meals after traditional hexane extraction exhibited the best antioxidant activities, including DPPH free radical-scavenging assay and hydroxyl radical scavenging activity among all the polysaccharide fractions. The research provides valuable information for making efficient use of sunflower seeds in the food industry.

Roasting pretreatment enhances the commercial qualities of tigernut oil. Oil extraction leaves behind meal, which is a potential source of starch. For industry to use this starch, its physicochemical characteristics of starch in meals after oil extraction with different roasting temperatures must be known, but have not been reported. In this investigation, the physicochemical properties of starches extracted from tigernut tubers before and after roasting at four different temperatures were investigated. Roasting increased the number of double helices and the ratios of A chains while decreasing crystallinity. There were differences in starch structure among samples roasted at different temperatures, which induced functional differences. The increase in A chains led to a decrease of peak viscosity, and improvement in freeze-thaw stability; the destruction of molecular interactions caused a decrease in pasting temperature; damage to the crystalline structure caused the decrease in gelatinization enthalpy and transition temperatures. As for differences in rheological properties, the interference of non-starch components and molecular interactions appear to be major factors. This study provides scientific information for the complete utilization of tigernut tubers.

Sesame is an industrial crop widely planted in China. Sesame capsules and stalks are by-products of sesame oil production. The production of these byproducts is large, but their utilization rate is low. As lignocellulosic biomass, sesame stalks and capsules contain plentiful amounts of lignin. In this study, the ethanol organosolv method was used to isolate lignin from black sesame capsules (BSL-1) and stalks (BSL-2), and white sesame capsules (WSL-1) and stalks (WSL-2). In order to promote full utilization of these lignins, their structural features and chemical composition were investigated and are here reported for the first time; antioxidant capacities were also analyzed. Among the four lignin fractions, the yield of BSL-1 was highest (53.94%). Capsules (47.04%-53.94%) consistently yielded more lignin than stalks (40.23%–40.90%). The predominant monosaccharides associated with BSL-1, WSL-1, and WSL-2 (i.e., all except BSL-2) were glucose. BSL-2 showed the highest thermal stability with the highest molecular weight. A similar composition ratio of linkages (β-O-4', β-β', and β-5') was observed in BSL-1 and WSL-1, and in BSL-2 and WSL-2. All the lignins belong to the GSH type and had S/G ratio values (2.36–3.05) greater than 2.0. Antioxidant studies showed that BSL-1 had the highest DPPH scavenging activity (RSI = 3.31), WSL-2 had the highest ABTS scavenging activity (RSI = 16.31), and WSL-1 had the highest reducing power values. The current study advances understanding of the structural differences of organosolv lignin from sesame capsules and stalks and should promote their future applications.

The comparative advantage of using vegetable fibers as reinforcement (fillers) attracted manufacturing industries over conventional composites. Natural fibers are purely green features that can easily decompose in a normal way to water and CO2 when encountered with moisture during their disposal. In this research, the effect of pre-treatment and properties of ramie fibers reinforced polylactic acid (PLA) composite were studied. Before the composite preparation, ramie fibers were soaked in a solution of alkali (sodium hydroxide) and silane coupling agent to provide better compatibility between ramie fibers and PLA interface. Additionally, a design containing nine samples was conducted to study the effect of temperature, fiber volume ratio, molding pressure and time on composite fabrication. From the results, optimum processing parameters were identified based on the tensile, bending and impact strengths improvement from various tested samples. Furthermore, this study highlights the degradation proc...

Background In recent years, cold-pressed oils have become more and more popular with consumers. However, their oxidative stability is low. Improving the oxidative stability of cold-pressed oils will increase their shelf life. Maillard reaction products (MRPs) have been shown to promote the oxidative stability of lipids. In this study, products from the Maillard reaction of reducing sugars and sesame enzymatically hydrolyzed protein (SEHP) were added to cold-pressed sesame oils to improve their oxidative stability. Results Three types of MRPs from reducing sugars (xylose, fructose, and glucose) and SEHP were prepared. Xylose-SEHP MRPs prepared under optimum conditions had the highest antioxidant activities among the three. The optimum conditions for xylose-SEHP were as follows: reaction temperature, 130 °C; reaction time, 180 min; pH, 6.5; and sugar/protein ratio, 10:1. The addition of xylose-SEHP MRPs at a level of 20 g kg-1 could significantly improve the oxidative stability of cold-pressed sesame oil. Besides, the addition of MRPs reduced the loss of tocopherol. The interaction of MRPs with endogenous antioxidants in the sesame oil (sesamol and tocopherol) was proved by comparison with lard. There was a synergistic increase in antioxidant activity for the combination of MRPs and sesamol and the combination of MRPs and tocopherol. Conclusions The results provide evidence that adding certain MRPs can improve the oxidative stability of cold-pressed sesame oil. © 2019 Society of Chemical Industry.

To investigate the composition and structural characteristics of cell wall polysaccharides, three pectic fractions and two hemicellulose fractions, namely water-soluble pectin (WSP), chelator-soluble pectin (CSP), sodium carbonate-soluble pectin (NSP), 1 mol/L KOH soluble hemicellulose (KSH-1) and 4 mol/L KOH soluble hemicellulose (KSH-2), were isolated from Chinese quince fruits. The five fractions exhibited structural and compositional variation. The results showed NSP was the predominant cell wall polysaccharide fraction in the fruit. All pectic fractions had a low degree of esterification (31.7–42.4%). WSP fraction had the highest thermal stability among the five fractions. The polysaccharide chain lengths ranged from 19.4 nm to 121.4 nm. CSP had the highest molecular weight, giving it also the highest solution viscosity. NMR spectra revealed that NSP was composed of RG-I and galacturonic acid main chains, KSH-1 was composed of 1,4-β-D-Xylp backbone attached to 1,5-α-L-Araf units. Among the five fractions, CSP has the highest DPPH radical scavenging activity while KSH-1 has the highest reducing power. This study can contribute to the applications of Chinese quince fruit polysaccharides in food and pharmaceutical industries.

Background Psoralen is a coumarin-like and coumarin-related benzofuran glycoside, which is a commonly used traditional Chinese medicine to treat patients with kidney and spleen-yang deficiency symptom. Psoralen has been reported to show estrogen-like activity, antioxidant activity, osteoblastic proliferation accelerating activity, antitumor effects and antibacterial activity. However, the antitumor mechanism of psoralen is not fully understood. This study aimed to investigate the therapeutic efficacy of psoralen in human hepatoma cell line SMMC7721 and the mechanism of antitumor effects. Results Psoralen inhibited proliferation of SMMC7721 in a dose- and time-dependent manner, and promoted apoptosis. Further, psoralen activated the ER stress signal pathway, including the expansion of endoplasmic reticulum, increasing the mRNA levels of GRP78, DDIT3, ATF4, XBP1, GADD34 and the protein levels of GDF15, GRP78, IRE1α, XBP-1s in a time-dependent manner. Psoralen induces cell cycle arrest at G1 phase by enhancing CyclinD1 and reducing CyclinE1 expression. Moreover, TUDC couldn’t inhibit the psoralen-induced ER stress in SMMC7721 cells. Conclusions Psoralen can inhibit the proliferation of SMMC7721 cells and induce ER stress response to induce cell apoptosis, suggesting that psoralen may represent a novel therapeutic option for the prevention and treatment hepatocellular carcinoma. Electronic supplementary material The online version of this article (10.1186/s40659-019-0241-8) contains supplementary material, which is available to authorized users.

The application of cold-pressed sesame oil (CSO) in the food industry is limited by its weak oxidative stability. The objective was to improve the oxidative stability of CSO by using different solid acid catalysts (SACs) with heat. The effects of SACs on the physicochemical properties, lignan content, oxidative stability and antioxidant capacity of oil samples were investigated. The different oil samples were: CSO without catalyst or heat (L); CSO without catalyst but with heat (CK); and CSO treated with four different SACs, namely hydrogen beta zeolite (Hβ), citric acid (CA), CA loaded on Hβ (CA/Hβ), 12-tungstophosphoric acid (PA) and PA loaded on Hβ (PA/Hβ). In the oil samples treated with SACs, the content of sesamin and sesamolin decreased significantly, and the content of asarinin and sesamol increased accordingly. The oxidative stability and antioxidant capacity of the oil samples Hβ, CA/Hβ and PA/Hβ were significantly enhanced (P

Nano-sized starch particles were prepared from potato starch via high-energy ball milling, which is a purely physical method. Scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and viscometer were used to analyze the morphology and characteristics of the as-prepared nanoparticles. Spherical particles with an average size of approximately 120 nm were obtained after grinding the samples for 90 min, and the particles were free from any contamination. The particle surface was rough with a plush-like feature, and the adsorption ability was six times higher than that of native starch. Thus, the nano-sized starch particles can be used as a good embedding medium in biomedical and chemical materials.

Ethnopharmacological relevance Osthole is an O-methylated coumadin, which was isolated and purified from the seeds of Cnidium monnieri (L.) Cusson. Osthole is a commonly used traditional Chinese medicine to treat patients with Kidney-Yang deficiency patients, who exhibit clinical signs similar to those of glucocorticoid withdrawal. However, the mechanism of action of osthole is not fully understood. Objective This study was designed to reveal the effects of osthole on corticosterone production in mouse Y1 cell. Materials and methods Mouse Y1 adrenocortical cells were used to evaluate corticosterone production, which was quantified by enzyme-linked immunosorbent assay (ELISA) kits. Cell viability was tested using the MTT assay, and the mRNA and protein expression of genes encoding steroidogenic enzymes and transcription factors was monitored by quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR) and western blotting, respectively. Results Osthole stimulated corticosterone secretion from mouse Y1 cells in a dose- and time-dependent manner, and osthole enhanced the effect of dibutyryl-cAMP (Bu2cAMP) on corticosterone production. Further, osthole also increased StAR and CYP11B1 mRNA expression in a dose-dependent manner and enhanced the expression of transcription factors such as HSD3B1, FDX1, POR and RXRα as well as immediate early genes such as NR4A1. Moreover, osthole significantly increased SCARB1(SRB1) mRNA and StAR protein expression in the presence or absence of Bu2cAMP; these proteins are an important for the transport of the corticosteroid precursor cholesterol transport into mitochondria. Conclusions Our results show that the promotion of corticosterone biosynthesis and secretion is a novel effect of osthole, suggesting that this agent can be utilized for the prevention and treatment of Kidney-Yang deficiency syndrome.

AIM: To observe the effect of topical 0.05% cyclosporine A (CsA) on the ocular surface and tear protein lacritin in a botulinum B-induced dry eye rat model. METHODS: A total of 36 female SD rats were randomly divided into 3 groups, botulinum B was injected into the right lacrimal gland of all rats. Group A and group B were treated with 0.05% CsA and 0.1% sodium hyaluronate, respectively, 3 times daily. The control group was not treated. Basal tear flow, corneal epithelial defects, and lacritin levels were measured. RESULTS: Tear secretion in all rats was reduced on day 3 and was even lower on day 7 postoperation (P

Lignin is an increasingly valuable raw material for industrial, pharmaceutical and the food industries; natural antioxidants are also being used more and more widely. The Chinese quince fruits have an abundance of lignins with antioxidant properties; however, the lignins cannot be isolated by the methods conventionally used on other sources (e.g., wood, straw). In this investigation, multi-enzymatic hydrolytic pretreatments were used to isolate lignins from Chinese quince fruit, and the structures of these multi-enzyme mixture lignin (EML) fractions were then analyzed and compared with conventional cellulolytic enzyme lignin (CEL). EML fractions are structurally similar to CEL fractions except for an increased S/G ratio, greater number of β-O-4 linkages, higher average molecular weight and decreased thermal stability. The EML-2 fraction in particular seemed most representative of the lignins isolated, and it exhibited the highest antioxidant activity in comparison with CEL and other EML fractions.

A molybdenum disulfide (MoS2) layered system is a two-dimensional (2D) material, which is expected to provide the next generation of electronic devices together with graphene and other 2D materials. Due to its significance for future electronics applications, gaining a deep insight into the fundamental mechanisms upon MoS2 fracture is crucial to prevent mechanical failure toward reliable applications. Here, we report direct experimental observation and atomic modeling of the complex failure behaviors of bilayer MoS2 originating from highly variable interlayer frictions, elucidated with in situ transmission electron microscopy and large-scale reactive molecular dynamics simulations. Our results provide a systematic understanding of the effects that different stacking and loading conditions have on the failure mechanisms and crack-tip behaviors in the bilayer MoS2 systems. Our findings unveil essential properties in fracture of this 2D material and provide mechanistic insight into its mechanical failure.

Magnetic nanoparticles Fe3O4 were prepared by hydrothermal coprecipitation of ferric and ferrous ions using NaOH. The surface modification of Fe3O4 nanoparticle by dendrimers has rendered the nanoparticle surface with enriched amine groups which facilitated the adsorption and conjugation of thioglycolic acid (TGA) modified CdTe quantum dots to form a stable hybrid nanostructure. Three generations (first generation: G0F, second generation: G1F, third generation: G3F) of bifunctional dendrimeric Fe3O4/CdTe nanoparticles were successfully prepared using this technique and characterized by microscopy. The optical and magnetic properties of the dendrimeric Fe3O4/CdTe nanoparticle were also investigated. The microscopic study reveals 3 different sizes for 3 generations, 16 nm (G0F), 31 nm (G1F) and 47 nm (G3F). Among three generations of nanoparticles, the G1F has the best optical property with a luminescent quantum yield of 25.6% and the G0F has the best magnetic property with a saturation magnetization of 19.3 emμ/g.

An efficient method of preparing nanostarch using high-intensity ultrasonic irradiation and acid hydrolysis was discussed. The transmission electron microscope (TEM) showed that the nanosized starch particles were in shape of sphere with the size of 80-120 nm, and their surfaces were rough with many flocci. The Fourier transform infrared spectrometer (FT-IR) revealed that the products maintained the original biological characteristics, and the molecules did not undergo any chemical changes. In addition, the effects of experimental conditions were analyzed and a plausible mechanism was proposed to explain the formation of the nanostarch.

Wood is a biological material with outstanding mechanical properties resulting from its hierarchical structure across different scales. Although earlier work has shown that the cellular structure of wood is a key factor that renders it excellent mechanical properties at light weight, the mechanical properties of the wood cell wall material itself still needs to be understood comprehensively. The wood cell wall material features a fiber reinforced composite structure, where cellulose fibrils act as stiff fibers, and hemicellulose and lignin molecules act as soft matrix. The angle between the fiber direction and the loading direction has been found to be the key factor controlling the mechanical properties. However, how the interactions between theses constitutive molecules contribute to the overall properties is still unclear, although the shearing between fibers has been proposed as a primary deformation mechanism. Here we report a molecular model of the wood cell wall material with atomistic resolution, used to assess the mechanical behavior under shear loading in order to understand the deformation mechanisms at the molecular level. The model includes an explicit description of cellulose crystals, hemicellulose, as well as lignin molecules arranged in a layered nanocomposite. The results obtained using this model show that the wood cell wall material under shear loading deforms in an elastic and then plastic manner. The plastic regime can be divided into two parts according to the different deformation mechanisms: yielding of the matrix and sliding of matrix along the cellulose surface. Our molecular dynamics study provides insights of the mechanical behavior of wood cell wall material at the molecular level, and paves a way for the multi-scale understanding of the mechanical properties of wood.

Inspired by the hierarchical structure of nacre and the robust adhesive ability of mussel threads, graphene oxide–polydopamine (GO–PDA) nanocomposites are designed and synthesized to achieve enhanced mechanical properties and to provide additional functionalities. Here we report a joint experimental/computational investigation of GO–PDA nanocomposites, proposing a probable chemical reduction mechanism of PDA to convert GO to reduced GO (rGO), which helps increase the electrical conductivity. The most stable chemical connection between PDA and GO is also proposed. Our artificial nacre-like GO–PDA nanocomposites are shown to have higher tensile strength and toughness compared to natural nacre. The pulling tests conducted by molecular dynamics simulations, which are supported by our experiments, reveal that the enhanced mechanical strength of GO–PDA nanocomposites mainly originates from the additional non-covalent interactions provided by PDA. The humidity-driven shrinking mechanism of GO–PDA nanocomposites due to non-uniform stresses on the GO–PDA sheets is also discovered in our simulations and supported by our experiments. The findings in this work can help improve and tune the properties of GO–PDA nanocomposites and might also apply to other 2D materials.

We studied the alkaloid constituents and bioactivity of Sophora flavescens (Leguminosae). The constituents were isolated with silica gel column chromatography, semi-preparative HPLC, Sephadex LH-20, and MPLC packed with MCI gel, and their structures were elucidated on the basis of physical characteristics and spectral data. Compounds 1 and 5-8 were evaluated for their in vitro cytotoxicity against human tumor HL-60, SMMC-7721, A-549, MCF-7, and SW-480 cell lines. Ten alkaloids were obtained, and their structures were identified as 17 beta-hydroxysophoridine (1), matrine (2), sophocarpine (3), sophoridine (4), isomatrine (5), 7,11-dehydromatrine (6), mamanine (7), sophoranol (8), oxymatrine (9), and oxysophocarpine (10). Compound 1 is a new alkaloid, and compound 7 was isolated from the Sophora flavescens for the first time. None of the compounds were cytotoxic to five human cancer cell lines.

Jasmonic acid (JA) signalling plays an important role in plant resistance to pathogens. Previously, JA has been found to play a role in induced disease resistance to necrotrophic pathogens in various plant species, but current researches showed that JA also enhanced resistance to biotrophic pathogens. However, its role in wheat (Triticum aestivum L.) powdery mildew (Blumeria graminis f. sp. tritici, Bgt) resistance reaction is largely unknown. To settle this issue, several typical powdery mildew resistant and susceptible wheat varieties were employed. The sensitivity to exogenous methyl jasmonate (MeJA) to wheat powdery mildew resistance, the concentration fluctuation of endogenous JAs after Bgt inoculation, and the expression profiles of nine pathogenesis-related protein genes (PR genes) after MeJA and Bgt treatments were studied systematically. Exogenous MeJA significantly enhanced the powdery mildew resistance of the susceptible varieties. After inoculation with Bgt, endogenous JAs accumulated rapidly, reached the maxima at 2 to 5 h post-inoculation (hpi), then decreased rapidly, and the concentration was almost the same as that of un-inoculated control at 96 hpi. The expression levels of the nine PRs were measured by real time quantitative RT-PCR (qRT-PCR) at different time points after MeJA application or Bgt inoculation respectively. The MeJA and Bgt strongly activated PR1, PR2, PR3, PR4, PR5, PR9, PR10 and Ta-JA2, but almost didn’t affect Ta-GLP2a. The induced powdery mildew resistance was positively correlated with the activated PR genes. JA plays a positive role in defence against Bgt. JA is a signalling molecule in wheat powdery mildew resistance and future manipulation of this pathway may improve powdery mildew resistance in wheat breeding.