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Cyclohexanone is widely used in coatings, pesticides, dyes, lubricants, and other industries due to its high solubility and low volatility, but designing highly active and stable heterogeneous cata...

Background As one of the most important modified products of rosin, rosin glyceride was widely used in many aspects. However, the preparation of rosin glyceride is always unfriendly due to the use of liquid catalyst, such as H2SO4 and H3PO4. Methods The rosin glyceride with low acid value was synthesized in vacuum conditions using a novel Lewis acidic ionic liquid 1–butyl–3–methylimidazolium chloroscandinate[BuMeim][Sc2Cl7] as catalyst. The [BuMeim][Sc2Cl7] is of excellent catalytic activity and stability. The efficient catalytic activity was studied via the combined Density Functional Theory (DFT) and experimental conditions. Significant findings The DFT proved the free energy of the esterification could reach to 31.6 Kcal/mol, which illuminates that the excellent coordination of the anions and cations in the [BuMeim][Sc2Cl7] greatly reduces the reaction energy barrier and promotes the efficient progress of the reaction. As a result, [BuMeim][Sc2Cl7] is a good catalyst for the esterification of rosin and glycerol to prepare rosin glyceride. Furthermore, [BuMeim][Sc2Cl7] could be a potential catalysts for the other esterification.

Levulinic acid (LA) is considered as an important intermediate for production of chemicals, resins, polymers, and fuel additives. Herein, five Bronsted–Lewis acidic ionic liquids (ILs) were synthesized and their acidities of ILs were characterized using FT-IR spectroscopy. The order of their acidic strength was similar to that of the used metal chlorides (ZnCl2 > FeCl3 > CuCl > CrCl3). Cellulose was effectively converted to LA in pure water at 180 °C in 10 h without additives, and the maximum yield of LA was more than 49% over the Bronsted–Lewis IL [HO3S-(CH2)3-py]Cl-FeCl3. The synergistic catalytic effect of the Lewis and Bronsted acidic centers of the catalyst played a significant role for the conversion of cellulose to LA. Some solid residues were formed along with the synthesis of LA, and the result of its characterization suggested that they had good thermal stability and their structures were benzene or amorphous (partially hydrogenated) fused benzene ring. Otherwise, the IL reusability was good, and when it was reused for five times, its catalytic performance was not changed. Therefore, the conversion route for cellulose to LA in pure water with the Bronsted–Lewis acidic ILs provides an environmentally friendly method for biobased-platform from biomass.

The preparation of small molecule compounds with a high value from biomass has always been the focus of research, and catalysts with high activity and stability are an essential part of biomass con...

A green and facile synthesis of anisotropic 3D architecture high-performance carbon catalyst has been a hot research topic. Herein, a facile and scalable strategy was developed to fabricate an N, S co-doped microcellular carbon from natural polymers of chitosan (N-source) and lignosulfonate (S-source), with the properties enhanced as a result of pre-cryocrushing of natural polymer-based carbon precursors. The as-prepared 3D architecture carbon is mechanically strong and contains cross-linked hierarchical porous micro-sheets and micro-channels. This N and S co-doped carbon, prepared from pre-cryocrushing of chitosan (60%) and lignosulfonate (40%) precursor (NSC/CC-C/L (60/40)), annealed at 900 °C shows unique structures, with significant defects, rough edges, rich micro/meso-pores, large surface area, N and S doping, and high pyridinic-N and thiophene-S contents. The NSC/CC-C/L (60/40)-900 sample exhibits superior performance with favorable kinetics, methanol resistance, and excellent durability as an ORR catalyst, all of which are much better than a commercial Pt/C and most reported metal-free catalysts. Impressively, the onset potential of the NSC/CC-C/L-900 sample reaches 1.08 V (vs. reversible hydrogen electrode) and the half-wave potential is 0.98 V, which are compared to 1.02 and 0.92 V for Pt/C.

Herein, we have successfully synthesized phosphorus/nitrogen/silicon tri-elements compound phosphazene derivative hexa-[4-( N-(3-(triethoxysilyl)propyl)acetamide)phenoxy]cyclotriphosphazene (HNTPC) from hexachlorotriphosphazenitrile, methyl 4-hydroxybenzoate, and 3-triethoxysilylpropylamine, and it was used as an additive flame retardant in epoxy resin (EP). Then, the thermal stability and flame retardancy of the composite (HNTPC/EP) were tested. Thermogravimetric analysis showed that the presence of HNTPC made EP matrix decompose at a relatively low temperature, thus promoted the formation of a stable coke layer and protected the matrix from fire. Therefore, the amount of carbon residue was markedly increased at 800°C, indicating an outstanding condensed phase flame-retardant effect. Furthermore, various combustion test data manifested that the addition of HNTPC could significantly improve the flame-retardant performance of EP. In addition, the sample could pass the vertical burning tests (UL-94) V-1 grade when the addition amount was 10% and the limiting oxygen index value was 32.6%, the peak heat release rate and total heat release rate decreased by 40.0% and 21.5%, respectively. Besides, the results of scanning electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy also showed that HNTPC can promote the formation of carbon layer and improved the flame-retardant property of EP. Finally, the condensed phase and gas phase synergistic flame-retardant mechanism of HNTPC was proposed.

Ornamental kale is popular because of its colorful leaves and few studies have investigated the mechanism of color changes. In this study, an ornamental kale line (S2309) with three leaf colors was developed. Analysis of the anthocyanin, chlorophyll, and carotenoid contents and RNA-seq were performed on the three leaf color types. There was less chlorophyll in the white leaves and purple leaves than in the green leaves, and the anthocyanin content was greatest in the purple leaves. All the downregulated DEGs related to chlorophyll metabolism were detected only in the S2309_G vs. S2309_W comparison, which indicated that the decrease in chlorophyll content was caused mainly by the inhibition of chlorophyll biosynthesis during the leaf color change from green to white. Moreover, the expression of 19 DEGs involved in the anthocyanin biosynthesis pathway was upregulated. These results provide new insight into the mechanisms underlying the three-color formation.

Background & Aims Non-alcoholic steatohepatitis (NASH) is associated with the dysregulation of lipid metabolism and hepatic inflammation. The causal mechanism underlying NASH is not fully elucidated. This study investigated the role of β-Arrestin1 (ARRB1) in the progression of NASH. Methods Liver tissue from patients with NASH and controls were obtained to evaluate ARRB1 expression. NASH models were established in Arrb1-knockout and wild-type mice fed either a high-fat diet (HFD) for 26 weeks or a methionine/choline-deficient (MCD) diet for 6 weeks. Results ARRB1 expression was reduced in liver samples from patients with NASH. Reduced Arrb1 levels were also detected in murine NASH models. Arrb1 deficiency accelerated steatohepatitis development in HFD-/MCD-fed mice (accompanied by the upregulation of lipogenic genes and downregulation of β-oxidative genes). Intriguingly, ARRB1 was found to interact with growth differentiation factor 15 (GDF15) and facilitated the transportation of GDF15 precursor (pro-GDF15) to the Golgi apparatus for cleavage and maturation. Treatment with recombinant GDF15 ablated the lipid accumulation in the presence of Arrb1 deletion both in vitro and in vivo. Re-expression of Arrb1 in the NASH models ameliorated the liver disease, and this effect was greater in the presence of pro-GDF15 overexpression. By contrast, the effect of pro-GDF15 overexpression alone was impaired in Arrb1-deficient mice. In addition, the severity of liver disease in patients with NASH was negatively correlated with ARRB1 expression. Conclusion ARRB1 acts as a vital regulator in the development of NASH by facilitating the translocation of GDF15 to the Golgi apparatus and its subsequent maturation. Thus, ARRB1 is a potential therapeutic target for the treatment of NASH. Lay summary Non-alcoholic steatohepatitis (NASH) is associated with the progressive dysfunction of lipid metabolism and a consequent inflammatory response. Decreased ARRB1 is observed in patients with NASH and murine NASH models. Re-expression of Arrb1 in the murine NASH model ameliorated liver disease, an effect which was more pronounced in the presence of pro-GDF15 overexpression, highlighting a promising strategy for NASH therapy.

Hβ zeolite is modified in the microwave acetic acid and evaluated in the one-pot synthesis of anthraquinone from benzene and phthalic anhydride. Under the optimized conditions, the Hβ zeolite modified in 0.9 mol/L acetic acid solution exhibits the best catalytic activity, in which the conversion of phthalic anhydride and its selectivity to anthraquinone are 54.71% and 62.56%, respectively. A series of catalysts are characterized using BET, XRD, XRF, NH3-TPD, FT-IR, Py-IR, SEM, and XPS. The high activity is mainly attributed to the suitable acid strength. Increasing the specific surface area and pore volume fraction also promotes the reaction. On the other hand, the deposition of carbon atoms results in the deactivation of the catalyst. However, the catalytic activity can be effectively recovered by calcination regeneration, and still shows good catalytic activity after five times.

This study presents a sustainable pathway for fractionating corn stover to produce glucose, high-quality lignin nanoparticles (LNPs), and levulinic acid (LA) based on the use of p-toluenesulfonic a...

Neuroinflammation is a key factor that contributes to the secondary injury after cerebral ischemia/reperfusion (CI/R) injury. Chemokine receptor type 5(CCR5) has shown its pro-inflammatory effects during central nervous system (CNS) diseases. However, the role of CCR5 in CI/R injury is still unclear. In this study, we administered maraviroc (MVC,APEXBIO,UK-427857), a CCR5 antagonist, to the middle cerebral artery occlusion(MCAO) mice. In vivo studies showed that MVC was successively intraperitoneally (i.p.) with different doses (5, 20, or 50 mg/kg body weight) for 3 days after mice MCAO. MVC showed its neuroprotective effects in alleviating neurological deficits and infarct volumes after MCAO. The level of apoptosis and inflammation were remarkably decreased by MVC treatment after CI/R injury. Subsequently, primary microglia were stimulated with different doses of MVC (0.2, 2, 20 or 200nM) for 12h after oxygen-glucose deprivation/reoxygenation model (OGD/R) in vitro. MVC significantly increased the viability of primary microglia after (OGD/R). The expression of pro-inflammatory cytokines (IL-1β and IL-6) in microglia were down-regulated by MVC treatment. Mechanistically, MVC also inhibited the secretion of IL-1β and IL-6 by microglia after OGD stimulation. Furthermore, the key components of NF-κB pathway were measured in vivo and in vitro after MCAO and OGD. MVC significantly inhibited the activity of NF-κB pathway in the above pathological environments. Finally, our data indicated that MVC treatment decreased the activation of JNK signaling pathway after CI/R injury in vivo and in vitro. The JNK activator anisomycin (AN，Beyotime，SC0132-5mg) reversed the neuroprotective effects of MVC, indicating that the JNK pathway is involved in the anti-inflammatory and anti-apoptotic mechanisms of MVC in CI/R injury. Our data demonstrated that CCR5 inhibition exhibits neuroprotective effects after CI/R injury. MVC, which is widely used for HIV treatment by its anti-virus effect, is a potential drug for the treatment of ischemic stroke in the future clinical trials.

Ruthenium (Ru) nanoparticles synthesized using hydroxyethyl cellulose (HEC-Ru) were used to hydrogenate α-pinene in an aqueous medium. The results showed that HEC had a good dispersion effect on Ru nanoparticles and most of the particle sizes were ranged from 4 to 6 nm. The micelles formed with HEC appeared to act as “microreactors” in which the Ru nanoparticles had good stability and uniform distribution. In addition, α-pinene was loaded into the HEC micelles through hydrophobic interaction, resulting in good contact with Ru nanoparticles. Thereby, HEC-Ru nanoparticles significantly improved the hydrogenation of α-pinene, and 99.6% of α-pinene conversion and 98.6% of cis-pinane selectivity were obtained. Compared with the Pd/C, Ru/H2O, and HEC-Ru/ethanol catalyst systems, the HEC-Ru/H2O system had the maximum α-pinene conversion. In addition, considerable α-pinene conversion could be obtained after 10 times reuse with no fresh addition.

Salidroside is one of the bio-active compounds found in Rhodiola crenulata. To find an easy, time saving and efficient way to extract, purify and enrich salidroside from Rhodiola and other natural plants, we prepared a highly selective molecularly imprinted polymer (MIP) for extraction and preconcentration of salidroside using salidroside (SD) as a template, acrylamide (AM) as a functional monomer, ethylene glycol dimethacrylate (EDMA) as a crosslinking monomer, and dimethyl formamide (DMF) as a porogen. The performance of the MIPs was evaluated through selective recognition capacity and adsorption isotherms and kinetics. The results showed that MIPs possessed excellent specific recognition toward SD and could effectively discriminate its structural analogue. The application of the developed MIPs as a selective sorbent for solid-phase extraction (SPE) of SD was also investigated. Under the optimum conditions, a rapid, economical, and efficient method based upon MIP-SPE coupled with high-performance liquid chromatography (HPLC) was developed for the determination of SD in Rhodiola crenulata. The method showed satisfactory recoveries (from spiked real samples at 3 fortification levels of 0.5, 1 and 10 mg L−1) of 88.74%- 97.64% with relative standard deviations (RSDs) ranging from 2.05%–3.54%. Furthermore, MIP-SPE was successfully used to separate and purify SD from different parts in Rhodiola crenulata and it should be available for determination of salidroside in others herbs.

Improvements on reactivity and viscosity control of the prehydrolysis kraft (PHK) dissolving pulp in an efficient and sustainable way is of both fundamental and practical interest. In this study, we proposed a novel concept of using a simultaneous treatment consisting of mechanical refining (R) and phosphotungstic acid (PTA) catalysis (defined as R-PTAsim) for this purpose. Results showed that the simultaneous process (R- PTAsim) was more effective in improving Fock reactivity, from 47.2 to 83.5%, while the sequential process (initial refining, followed by PTA catalysis, defined as R-PTAseq) increased from 47.2 to 77.2%. The viscosity of resultant pulps was 411 mL/g and 428 mL/g for the R- PTAsim and the R-PTAseq, respectively. The explanations are: (1) the PTA catalysis induces cellulose depolymerization and morphological changes of fibers, and improves the mechanical refining efficiency, (2) mechanical refining facilitates the diffusion/adsorption of PTA into cellulose fibers and further enhances the PTA catalysis, (3) an enhanced synergistic effect occurs in simultaneous treatment. It was demonstrated that PTA has a high chemical stability and recyclability/reusability. This concept can offer a new pathway for sustainable manufacturing high- quality dissolving pulp.

In this work, Mo-MCM-41, Zr-MCM-41, Sn-MCM-41 and Ti-MCM-41 mesoporous molecular sieves were successfully synthesized via hydrothermal synthesis. An acidic group (SO42−, PTSA etc.) was introduced into the mesoporous molecular sieves to obtain modified mesoporous molecular sieve catalysts. The XRD, N2 absorption–desorption isotherms, FT-IR and Py-IR results reveal that PTSA/ZrO2/Mo-MCM-41 had a mesoporous molecular sieve structure containing a large number of acidic centers. The PTSA/ZrO2/Mo-MCM-41 catalyst illustrated superior catalytic performance for synthesis of rosin methyl ester and the esterification rate was 88.2% under the optimized conditions. At the same time, the PTSA/ZrO2/Mo-MCM-41 catalyst has excellent stability and can be recycled and reused with negligible loss in activity over six cycles.

Effective enzymatic hydrolysis of lignocellulosic materials to produce fermentable sugars requires close cooperation between cellulase components. However, lignin remaining in the pre-treated substrate plays an inhibitory role in the synergistic action of enzymes through irreversible adsorption. In this study, the effect of cellulolytic enzyme lignin (CEL) isolated from pre-treated furfural residues and dissolved lignins (DLs) precipitated from black liquor on cellulase and cellobiase adsorption behavior was investigated. Green liquor (GL) combined with H2O2 (GL-H2O2) or ethanol (GL-ethanol) pre-treatments markedly decreased the adsorption capacity of CELs. However, the DLs had the strongest binding ability, which was approximately two to three times higher than that of CELs. According to SDS–PAGE analyses, only CBHII and EGII in cellulase and enzymes of 245 kDa and 55 kDa molecular weight in cellobiase were easily bound onto CELs and DLs. Solid-state 13C NMR spectra and FT-IR analysis indicated that pre-treatments reduced the hydrophobic structure of aromatic rings, β-O-4, and carbonyl, and increased the number of hydrophilic carboxyl groups in CELs. For this reason, the hydrophobicity of CELs was decreased, thus reducing their adsorption capacity. Compared with GL-H2O2 pre-treatment, GL-ethanol pre-treatment had a stronger effect on decreasing enzyme adsorption of lignin due to its high hydrophilicity. Heavy damage to aromatic structures, low molecular weight, and the large number of aliphatic portions in DLs caused their strong affinity for enzymes, although their BET surface area and hydrophobicity were low.

Brønsted-Lewis acidic ionic liquids (ILs) were applied to catalyze cellobiose to prepare levulinic acid (LA) in one pot under hydrothermal conditions. Under the optimum conditions, the highest LA yield of 67.51% was obtained when low [HO3S-(CH2)3-mim]Cl-FeCl3 (molar fraction of FeCl3 x = 0.60) was used. This indicated the Brønsted-Lewis acidic ILs played an active role in the conversion of cellobiose to LA. The catalytic mechanism of ILs had been established, disclosing that the Brønsted-Lewis acidic ILs had the catalytic synergistic effect originating from its double acid sites. During the reaction process, the Lewis acid sites improved the isomerization of glucose to fructose, then the Brønsted and Lewis acid sites simultaneously enhanced the dehydration of fructose to produce hydroxymethylfurfural (HMF), which was propitious to the synthesize LA with high yield. In addition, LA could be easily extracted by methyl isobutyl ketone (MIBK), and the ILs could retain its basic activity after 5 cycles. The solid residues were characterized using SEM, FT-IR and TG-DTG spectroscopy. It was the conclusion that a large amount of humins were produced during the cellobiose conversion process. In this reaction, the ILs not only overcomes the problems of the conventional catalyst, but also completes the reaction-separation integration and the recycling of the catalyst. This paper provided an important theoretical basis for the application of ILs in the field of biomass.

Inspired by the hierarchical structure of natural nacre, a binary artificial nacre with excellent mechanical performance, tensile strength and toughness was successfully constructed based on water-soluble cellulose acetate (WSCA) and reduced graphene oxide (rGO). The tensile strength and toughness of the hybrid films were markedly improved by the introduction of rGO, and the tensile strength and toughness of the rGO/WSCA composite films reached 499.3 MPa and 9.6 MJ/m3 (rGO-WSCA-III), respectively, which are approximately 5.0 and 5.3 times that of natural nacre. In addition, the hybrid rGO/WSCA films showed better flame retardancy and stability in water, and high electrical conductivity. In this study, we provide a strategy to design and fabricate exceptionally strong and tough artificial nacre, which has potential application in tissue engineering and as a humidity sensor.

A new type of Pd@mSiO2 composite nanospheres with controlled pore structure, consisting of internal Pd cores and controlled mesoporous silica shells, has been prepared by a facile one-pot method. The thickness and pore size of the shell could be easily tuned by changing the amounts of TEOS and the hydrophobic block length, respectively, during synthesis. In this perspective, the effects of CTAB concentration, pH, and TEOS concentration on the monodisperse sphere morphology of Pd@mSiO2 nanoparticles (NPs) were investigated. In addition, a nucleation mechanism was proposed. Hydrogenation of nitrobenzene to aniline was used as a model reaction to discuss the effect of pore size on the transport rate of the reactants and the product selectivity in metal-catalyzed hydrogenation. The catalysts exhibited a high conversion rate and significantly enhanced stability, leading to a higher recyclability without loss of catalytic activity compared to conventional supported catalysts and commercial catalysts.

Phillyrin, a natural plant extract, has significant antioxidant and anti-apoptotic effects. However, its effect on intracerebral hemorrhage (ICH) remains unclear. In this study, we investigated a potential role for phillyrin in the regulation of the oxidative stress and apoptosis induced by ICH. A model of ICH was induced by collagenase IV (0.2 U in 1 μl sterile normal saline) in male C57BL/6J (B6) mice and different doses of phillyrin (5, 15, or 30 mg/kg) were intraperitoneally (i.p.) injected at 30 min, 6 h, and 22 h after modeling. We found that phillyrin significantly reduced neural function and lesion volume, improved injury of white and grey matter around the lesion, decreased apoptosis and oxidative stress, increased the expression of nuclear factor-erythroid 2-related factor 2 (Nrf2), heme oxygenase 1(HO-1), NADPH quinone oxidoreductase 1 (NQO1) and Superoxide Dismutase-1(SOD-1) in vitro and in vivo, and protected neurons from the stimulation of hemin by promoting Nrf2 nuclear translocation. Treatment with ML385 (Nrf2 inhibitor) completely reversed the protective effects of phillyrin in vivo after ICH injury. Based on our findings, we conclude that phillyrin treatment alleviates ICH injury-induced apoptosis and oxidative stress via activation of the Nrf2 signaling pathway, highlighting a potential role for phillyrin as an ICH therapeutic.

Cerebral ischaemia/reperfusion (CI/R) injury is a major challenge due to the lack of effective neuroprotective drugs. Hederagenin (HE) is the aglycone part of saponins extracted from Hedera helix Linné that has exhibited anti-apoptotic and anti-inflammatory effects; however, the role of HE in CI/R has not been elucidated. In this study, mice were intraperitoneally (i.p.) injected with HE (26.5, 53, or 106 μmol/kg body weight) for 3 days after middle cerebral artery occlusion (MCAO). Neural function and brain infarct volume were evaluated. HE treatment attenuated CI/R-induced apoptosis and inflammatory cytokine expression within the infarcted areas. HE treatment also decreased the activation of the MLK3 signalling pathway, which potentiates CI/R damage via the MAPK and NFκB pathways. Due to HE’s safety profile, it has potential to be used for the clinical treatment of ischaemic stroke.

Aflatoxin B1 (AFB1) occurrence in peanut oil samples randomly collected from family workshops in western Guangdong during 2016–2017 (n = 427) was surveyed. AFB1 content was screened by enzyme-linke...

Cationic polymers (cationic polyacrylamide (CPAM), polyethyleneimine (PEI) or cationic starch (CS)) were used to enhance the enzymatic hydrolysis of waste paper fibers (WPFs) at 15% (w/w) solids concentration. Results showed that 0.05 g/L PEI, CPAM and CS resulted in 72.5%, 65.9% and 59.7% conversion of WPFs, increased by 15.4%, 8.8% and 2.6%, respectively, compared with control (57.1%). PEI was shown to have a larger effect than CPAM and CS, and generate a total sugar concentration of 73.9 g/L. Improvement in hydrolysis with cationic polymer addition is attributed to increased cellulase adsorption on cellulose through electrostatic attraction, rather than enhancement of cellulase activity. A patching/ bridging mechanism of cationic polymer enhancement of cellulose adsorption in cellulose is hypothesized. PEI exhibited maximum cellulose binding for polymers examined and appears to promote binding through a patching mechanism. CPAM and CS adsorbed a relatively low cellulase through bridging mechanism. In addition, enzyme loading could be reduced by addition of cationic polymers to obtain the same glucose yield, especially when PEI was used.

Four kinds of thermoregulated ionic liquids (ILMPEG-400, ILMPEG-600, ILMPEG-750 and ILMPEG-1000) were synthesized and used as the stabilizer to build the thermoregulated phase-separation catalytic system containing the Pd nanoparticles catalyst. The results showed that the Pd nanoparticles exhibits high stability in the present of thermoregulated ionic liquids, and endowed the catalytic system with a good thermoregulated phase separation property, namely, the monophasic reaction combined with a biphasic separation. The nanoparticle thermoregulated catalytic system had an excellent catalytic performance for the hydrogenation of fatty acid methyl ester, and the conversions of carbonyl group and carbon-carbon double bond in fatty acid methyl ester were 97% and 91.1%, respectively, when the reaction was carried out at 210 °C for 4 h. The product was easily separated from the catalytic system and the reusability of the separated catalytic system was good.

Fe3O4@C supported ultrasmall and highly monodisperse ruthenium (Ru) nanoparticles (Ru/Fe3O4@C) were prepared as novel nanocatalysts for hydrogenation reactions. The catalysts displayed high activity for the hydrogenation of rosin to form hydrogenated rosin with extraordinary selectivity. The role of controlled carbon size on the catalytic properties of the catalysts was studied. The Ru/Fe3O4@C catalyst can be easily separated from the organic solvent by applying an external magnetic field and the separated Ru/Fe3O4@C can simply and efficiently used in ten consecutive runs without significant decrease in activity. Significantly, Ru/Fe3O4@C nanocatalysts showed a wide substrate scope for hydrogenation reactions under mild conditions.

Pyrolysis oil of rubber seed oil (RSO) was upgraded by methyl esterificationusingSO42−/ZrO2 solid acid as catalyst. The activity and reusability of SO42−/ZrO2 solid acid were investigated and the experiment indicated that the esterification rate could reach 99.62% and was still above 95% in the third reaction. The component of SO42−/ZrO2 solid acid changed little after the third used. The properties of the obtained biofuel were studied and the results showed they were superior to pyrolysis oil and biodiesel, and similar to 0# diesel. The methyl esterification reaction kinetics was researched. The kinetics calculation indicated that the reaction order of the methyl esterification is 1.058, and Arrhenius equation can be expressed as k 1 = 7.711 × 10 6 e - 47.913 RT .

Ni-doped spherical mesoporous carbon catalysts (Ni/C n ) were prepared via one-pot hydrothermal carbonization of microcrystalline cellulose (MCC) with nickel acetate as the Ni source. This exhibited a high conversion rate for p-nitrophenol (PNP) hydrogenation to p-aminophenol (PAP). The obtained catalysts contained 0.87–6.84 wt% nickel content that primarily consisted of metallic nickel, with a small amount of nickel oxide. The Ni additive could be beneficial in the formation of the mesoporous structure. The results showed that as the Ni content increased, the mesoporous percentage increased. The doped Ni was monodispersed particles added into the carbon skeleton with an average particle size of 23.6 nm. They were surrounded by ordered striped carbon that exhibited a graphite-like structure. The catalytic hydrogenation reaction took place at normal temperatures and pressure exhibited high catalytic activity. The degradation rate of PNP reached 99.7% when 0.30 g of the Ni/C0.2-900 catalysts was used for a reaction time of 40 min, with corresponding apparent rates constant of 1.68 × 10−3 S−1, apparent activation energy of only 43.25 kJ/mol.

The alkylation reaction of isobutane with 2-butene to yield C8-alkylates was performed using Bronsted–Lewis acidic ionic liquids (ILs) comprising various metal chlorides (ZnCl2, FeCl2, FeCl3, CuCl2, CuCl, and AlCl3) on the anion. IL 1-(3-sulfonic acid)-propyl-3-methylimidazolium chlorozincinate [HO3S-(CH2)3-mim]Cl-ZnCl2 (x=0.67) exhibited outstanding catalytic performance, which is attributed to the appropriate acidity, the synergistic effect originating from its double acidic sites and the promoting effect of water on the formation and transfer of protons. The Lewis acidic strength of IL played an important role in improving IL catalytic performance. A 100% conversion of 2-butene with 85.8% selectivity for C8-alkylate was obtained under mild reaction conditions. The IL reusability was good because its alkyl sulfonic acid group being tethered covalently, its anion [Zn2Cl5]− inertia to the active hydrogen, and its insolubility in the product. IL [HO3S-(CH2)3-mim]Cl-ZnCl2 had potential applicability in the benzene alkylation reaction with olefins and halohydrocarbons.

The formation of Li dendrites is effectively inhibited by utilizing a small amount of polysulfide (1 to 2 mM Li2Sx, 2 ≤ x ≤ 8) in a conventional carbonate electrolyte to introduce a significant amount of polyethylene oxide (PEO)-like polymers into solid-electrolyte interphase (SEI) films. The polysulfide added likely acts as a catalyst rather than an additive, which is not consumed during repeated charging/discharging cycles. Thus the stability of Li-metal batteries during prolonged cycling is remarkably improved.

To provide theoretical and technical support for the broad application of fermentation polysaccharides by Fomes officinalis, the differences of polysaccharides extracted from fruiting bodies and fermentation broth of F. officinalis Ames were compared. Polysaccharide concentration was determined by the phonel-sulfate method, and monosaccharide compositions were analyzed by ion chromatography-integrated pulsed amperometric detector. Also, the antioxidant activities of the two samples were determined based on DPPH and hydroxyl radical scavenging oxidation experiments. The results indicated that polysaccharide contents of fruiting bodies and fermentation broth were 71.23% and 67.12%, respectively. The monosaccharide composition of fruiting body polysaccharide was glucose, galactose, mannose, and xylose from more to less, and that of fermentation polysaccharide was glucose, mannose, galactose, xylose, and arabinose. Both fruiting polysaccharide and fermentation polysaccharide are mainly composed of macromolecular polysaccharide, and the scavenging ability of hydroxyl radical is similar. The scavenging ability of DPPH radical of fermenting polysaccharides is higher than that of fruiting polysaccharides. Although there were some differences in polysaccharide contents, monosaccharide composition and molecular weight distribution between fruiting bodies and fermentation broth, the antioxidant activity of the two samples was similar.

Lithium-ion batteries with graphite as the anode consume ∼10% of the active lithium from the cathode to form a solid electrolyte interphase layer during the first cycle, resulting in a reduced reversible capacity. Here, we report using Li2S as a cathode pre-lithiation material to compensate for the loss of active lithium and, consequently, enhance the specific energy of lithium-ion batteries. A Li2S material with a core-shell structure is prepared by mixing Li2S, Ketjenblack (KB) and poly(vinylpyrrolidone) (PVP) in anhydrous ethanol, and the material shows a specific charge capacity of ∼1053 mAh g−1 (631 mAh g−1 based on the total weight of cathode pre-lithiation materials, binders and conductive additives). The ability of this material to compensate for active lithium is investigated by coating a typical cathode LiFePO4 as an example, with the core-shell Li2S/KB/PVP via a simple and non-toxic coating method. Our results show that the LiFePO4 (Li2S)/graphite full cell exhibits a specific discharge capacity of 146.7 mAh g−1 in the first cycle, which is the same as the specific discharge capacity of the LiFePO4 half cell. XPS analysis reveals Li2S decomposes into lithium ions and sulfur with release of electrons in the first charge. Such a successful extraction of the active lithium from Li2S results in excellent cycling performance with increased specific energy.

Summary In this research, the effects of culture substrates on taste component content of Lentinula edodes were studied, and the resulting taste quality of L. edodes was evaluated. The results revealed that single-carbon and single-nitrogen sources were beneficial to production of soluble sugars and polyols, organic acids and sweet amino acids, whereas a single-carbon source was beneficial to essential amino acid production, and a mixed-carbon source was beneficial to umami 5′-nucleotides and high mushroom production yield. High C/N values were beneficial to trehalose, arabitol, malic acid, and succinic acid production, while low C/N values were beneficial to mannitol and citric acid production. L. edodes fruiting bodies, harvested from a culture substrate containing single carbon, high proportion of cereal bran, had a more palatable taste quality, while a substrate containing bagasse and low C/N values was not suitable for L. edodes cultivation due to unfavourable taste quality. These results provide cultivation information how to obtain fruiting bodies L. edodes with more taste components.

Detailed investigation of the influence of surface modification using a typical oxide (TiO2) on the electrochemical cycling performance of LiNi0.5Mn1.5O4 at room temperature (25 °C) and elevated temperature (55 °C) is reported. This spinel cathode material is commonly surface-modified with various metal oxides to improve its electrochemical cycling performance in lithium ion batteries. However, the underlying mechanisms of such a treatment, with respect to the surface crystal structure and chemistry evolution, have remained unclear. Bare-LiNi0.5Mn1.5O4 and TiO2-modified LiNi0.5Mn1.5O4 both show excellent cycling performance, i.e. almost no capacity retention and ∼99% coulombic efficiency for 150 cycles, at room temperature. However, at 55 °C the latter shows significantly better electrochemical cycling performance, with 93% capacity retention and ∼96% coulombic efficiency for 100 cycles, than the former with 70% capacity retention and ∼93% coulombic efficiency. Via advanced electron microscopy techniques, we observed that titanium ions migrated into the surface region of LiNi0.5Mn1.5O4 during the surface modification process at high temperature and reconstructed the (1–3 nm) surface spinel structure into a rocksalt-like structure and the subsurface (several nanometers) into a pseudo-rocksalt-like structure. The reconstruction of the surface and subsurface of the LiNi0.5Mn1.5O4 spinel cathode material mitigates not only the migration of Mn ions from the bulk into the electrolyte but also the formation of a solid state electrolyte interface, which plays a critical role in the improvement of electrochemical cycling performance at elevated temperatures.

Lignin is considered as a renewable and sustainable resource for producing value-added aromatic chemicals and functional carbon materials. Herein, we develop a one-step catalyst-free depolymerization strategy to convert lignin into aryl monomers and carbon nanospheres simultaneously. Importantly, microwave-assisted depolymerization (MAD) in conjunction with dichloromethane (CH2Cl2) vapors is developed. The total mass yield of guaiacols reached the highest amount of 225.1 mg/g at 600 °C, and the highest yields of phenols (49.0 mg/g) and aromatic hydrocarbons (155.1 mg/g) were obtained at 700 °C. Hydrogen radicals and hydrogen chloride (HCl) are in-situ formed from CH2Cl2, significantly decreasing the activation barrier and reforming pyrolysis vapors to promote the formation of aryl monomers. Interestingly, uniform carbon nanospheres with an average size of 140 nm were produced as co-products at 700 °C. The microwave “hot-spots”, allied with the continuous surface erosion and the decrease in surface energy of lignin-derived carbon precursors by CH2Cl2 vapor, can be considered the driving force for the ultimate formation of carbon nanospheres. The CH2Cl2/MAD system produces aryl monomers (26.8 wt% yield) and carbon nanospheres (36.6 wt% yield) at 700 °C. We provide a facile, intriguing and scalable approach to convert lignin to valuable aryl monomers and sustainable carbon materials that can be applied in the chemistry, energy and environmental fields.

A novel fluorescence sensing strategy for determination of atrazine in tap water involving direct competition between atrazine and 5-(4,6-dichlorotriazinyl) aminofluorescein (5-DTAF), and which exploits magnetic molecularly imprinted polymer (MMIP), has been developed. The MMIP, based on Fe3O4-chitosan nanoparticles, was synthesized to recognize specific binding sites of atrazine. The recognition capability and selectivity of the MMIP for atrazine and other triazine herbicides was investigated. Under optimal conditions, the competitive reaction between 5-DTAF and atrazine was performed to permit quantitation. Fluorescence intensity changes at 515 nm was linearly related to the logarithm of the atrazine concentration for the range 2.32-185.4 μM. The detection limit for atrazine was 0.86μM (S/N=3) and recoveries were 77.6-115% in spiked tap water samples.

Chitosan and chitosan oligosaccharides (COS) have been reported to possess various biomedical properties, including antimicrobial activities, immuno-enhancing effects, and anti-tumour activities. COS have attracted considerable interest due to their physicochemical properties, and potential applications in the food and pharmaceutical industries, especially in cancer therapies. This paper describes the preparation of COS and their physicochemical properties, and modification, which aids understanding of their biological activities. Based on the latest reports, several biological and anti-tumour activities of COS will be discussed. The proposed anti-tumour mechanisms of COS are summarised, to provide comprehensive insights into research on the molecular level. Finally, the potential applications and future development of the biopolymer will be discussed.

Electrolytes compatible with lithium metal (Li) anode and cathode materials are regarded as one of the most crucial components toward the practical deployment of rechargeable lithium metal batteries (RLMBs). Herein, we report a highly salt-concentrated electrolyte (SCE) comprising lithium bis(fluorosulfonyl)imide (LiFSI) and 1,3-dioxolane (DOL)-based ether solvents for stable cycling of 4-V-class rechargeable Li cells. The selective addition of 1,8-diazabicyclo(5.4.0)undec‑7-ene (DBU) is capable of suppressing the ring-opening polymerization of DOL. The resulting LiFSI-DOL-based SCE shows excellent chemical stability (150 days), good anodic stability (ca. 5.0 V vs. Li/Li+), and decent ionic conductivity (1.3 mS cm−1) at room temperature. Using the LiFSI-DOL-based SCE, the Li || Cu cells exhibit dendrite-free Li deposition/dissolution processes with high Coulombic efficiencies (> 99%), and the Li || LiNi1/3Mn1/3Co1/3O2 cell shows good capacity retention (81% after 400 cycles). These results strongly suggest the feasibility of the LiFSI-DOL-based SCE as electrolyte for 4-V-class RLMBs.

In this work, a series of Pd@Al-MSiO2 yolk–shell-structured nanospheres (YSNSs) with different Al contents were synthesized by a facile one-pot method. The EDX elemental analysis and high-magnification TEM image of Pd@Al-MSiO2 YSNSs confirmed that its well-defined yolk-shell structure with a moving Pd core and mesoporous silica shell rich in Al species. Furthermore, Solid state NMR and Py-FTIR results confirmed that Al species grafting mainly formed 4-coordinated Al (AlO4) in the mesoporous silica framework which led to generating abundant Lewis acid sites. The influence of Al species on the physicochemical properties of Pd@Al-MSiO2 YSNSs, as well as their catalytic performance for the hydrogenolysis of glucose to 1,2-propylene glycol (1,2-PG), was investigated. The mesoporous silica shell with abundant Lewis acid sites is a significant contributor to the isomerization of glucose into fructose, while the Pd core plays a role in promoting the hydrogenation of intermediates. The unique hollow space inside the Pd@Al-MSiO2 YSNSs provides a location for the retro-aldol condensation of fructose and consequently avoids direct hydrogenation of fructose. The as-synthesized Pd@Al3-MSiO2 YSNSs shows superior catalytic activity (1,2-PG selectivity of 47.4%, glucose conversion of 95.4%) in the hydrogenolysis of glucose, and far outperforms the Pd/Al3-MSiO2 catalysts. In addition, owing to the influence of the 4-coordinated Al species on the geometry and chemical properties of the mesoporous silica shell, the nanospheres show good stability and reusability over multiple catalytic cycles without significant loss of activity.

Aromatic sulfonic acid, p-toluenesulfonic acid (p-TsOH), was employed to pretreat the corn stover in aqueous for improving the enzymatic hydrolysis of cellulose-enriched residue, and was compared to ethanol/water pretreatment. The glucose yield of corn stover from p-TsOH/water pretreatment (97.6 %) was higher than that from ethanol/water pretreatment (89.5 %) after 96 h hydrolysis with high cellulase loading of 15 FPU/g-cellulose. More than 80 % of glucose yield was still obtained with low cellulase loading (7.5 FPU/g-cellulose) after p-TsOH/water pretreatment, while only 65.2 % was obtained after ethanol/water pretreatment. Composition and structure analysis showed that p-TsOH/water pretreatment severely break the fibre, removed more lignin (especially of surface lignin), well increased cellulose accessibility, and resulted in more hydroxyl exposed on the surface. Moreover, more monomeric sugars (xylose and glucose) derived from hemicellulose were released after p-TsOH/water pretreatment, and they could be converted to valuable platform chemical of levulinic acid by simply heating the prehydrolysate.

We aim to develop a solid-phase extraction (SPE) based on a dummy molecularly imprinted polymer (MIP) and liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) for selective determination of four pyridine carboxylic acid herbicides (aminopyralid, picloram, fluroxypyr, and clopyralid) in milk samples. Using picloram as the dummy template, MIP nanocomposites with highly selective recognition and adsorption for the target molecule and its structural analogs were successfully synthesized by precipitation polymerization. Adsorption isotherms and kinetics were used to determine the adsorption performance and specific recognition mechanism of both MIPs and non-molecularly imprinted polymers (NIP). The Scatchard plot analysis revealed that two different binding sites were formed in the MIP with maximum binding capacity (Qmax) of 1171.8 μg·g−1 and 3022.5 μg·g−1, respectively. Recovery at three spiking levels of 10, 20, and 50 μg·L−1 ranged between 75.3 and 89.8% with relative standard deviations (RSDs)

The high-voltage spinel LiNi0.5Mn1.5O4 cathode material suffers from the rapid degradation of electrochemical cycling performance at elevated temperatures, which prevents its successful commercialization. Herein, we show that coating the surface of this material with Ta2O5, which has high resistance against hydrofluoric acid (HF) attack, is an effective way to improve its electrochemical cycling performance. A Ta2O5-coated LiNi0.5Mn1.5O4 half-cell shows a capacity retention of ∼93% and a Coulombic efficiency of ∼98% after 100 cycles at 55 °C, compared to the corresponding values of ∼76% and ∼95% measured for the bare LiNi0.5Mn1.5O4 half-cell. The detailed structural analysis of the Ta2O5-coated LiNi0.5Mn1.5O4 shows that a small amount of Ta5+ ions diffuse into the 16c site on the cathode surface during the coating process, as directly observed by Cs corrected scanning transmission electron microscopy. The modification of the LiNi0.5Mn1.5O4 surface with Ta5+, together with the residual Ta2O5 coating, stabi...

The present study aimed to investigate whether ginsenoside Rb1 (G-Rb1) attenuates spinal cord injury-associated oxidative stress in rats by regulating the endothelial nitric oxide synthase eNOS/nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase (HO)-1 signaling pathway. Sprague Dawley rats were randomly divided into the sham operation group (S group), spinal cord injury group (SCI group), G-Rb1 treatment group (G-Rb1 group) and SCI+G-Rb1+Inhibitor L-name group (L-name group). The posterior limb function was evaluated via the Basso, Beattie and Bresnahan scoring method. The levels of superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT) and glutathione (GSH) in serum were measured by ELISA. The pathological changes in the spinal cord were observed by H&E staining. Reverse transcription-quantitative polymerase chain reaction and western blot analyses were used to detect eNOS, phosphorylated (p)-eNOS, heat shock protein (HSP)90, Nrf2 and NAD(P)H quinone dehydrogenase 1 (Nqo1) at the mRNA and protein level. Immunohistochemistry was used to detect the expression of Nrf2 and p-eNOS. Compared with the S group, the scores of spinal cord function in the SCI group were significantly lower, and the levels of MDA were significantly increased, while the levels of SOD, CAT and GSH protein in spinal cord were significantly decreased (P

Herein, an imprinted electrochemical sensor based on graphene-Au nanoparticles incorporated with molecularly imprinted polymer (MIP) was fabricated for determination of 4-nonylphenol (4-NP). Grafted MIP electropolymerized on nanoscale multilayer films electrode was achieved using 4-NP as a template and P-aminothiophenol as a functional monomer. The electrochemical properties of the MIP nanoscale multilayer membrances were characterized and measured by cyclic voltammetry and differential pulse voltammetry techniques; using ferrocyanide/ferricyanide-redox marker. Several important parameters were optimized and investigated to improve the performance of the sensor. Under the optimized conditions, the developed sensor showed an excellent linear response over the concentration ranges of 50–500 ng mL−1 (4-NP) with a detection limit of 0.01 ng mL−1(S/N = 3). The developed sensor showed a good selective recognition of 4-NP compared with structural analogue, exhibited a good reproducibility and accuracy with long-term stability. At last, the feasibility of the proposed methodology was successfully applied fordetection of 4-NP in milk and its packaging materials.

Waste paper has considerable potential as a raw material for lactic acid (LA) production due to high cellulose content, abundance and low cost. In this study, four kinds of waste papers were used for LA production through simultaneous saccharification and fermentation (SSF) by Streptococcus thermophilus. The SSF of office paper achieved the highest LA concentration (39.71 g/L), while the highest LA yield was observed for magazine (99.56%), followed by office paper (82.85%). High LA concentration is unfavorable to total LA conversion because of product inhibition. However, the addition of Gleditsia saponin (GS) could obtain both high yield and high concentration of LA at a low enzyme loading, indicating that product inhibition could be moderated. A lactic acid yield of 86.30% was obtained from office paper at an enzyme loading of 9 FPU/g-cellulose with GS, which was higher than that of without GS at a higher loading of 18 FPU/g-cellulose.

Summary Pleurotus eryngii, the second largest industrial cultivation mushroom in China, is usually cultivated on substrates mainly consisting of sawdust and corncob. In this study, experiments were performed to determine the effects of different carbon sources and C/N values on nonvolatile taste components of P. eryngii. The effects of different carbon sources on nonvolatile taste components levels revealed that sawdust was beneficial to high levels of crude protein, amino acids, 5′-nucleotides and equivalent umami concentration, while corncob was beneficial to high contents of carbohydrate, polysaccharides and trehalose. At the similar C/N values, relatively higher sawdust content was beneficial to umami amino acid production, while relatively higher corncob content was beneficial to high contents of carbohydrate, polysaccharides and mannitol. Higher C/N value was beneficial to high levels of crude protein, amino acids, 5′-nucleotides and equivalent umami concentration, while lower C/N value was beneficial to high contents of carbohydrate, polysaccharides and trehalose. These results provided information for P. eryngii fruit body industrial cultivation to obtain specific nonvolatile taste components with high levels.

Green liquor (GL) combined with H2O2 (GL-H2O2) and green liquor (GL) combined with ethanol (GL-ethanol) were chosen for treating sugarcane bagasse. Results showed that the glucose yield (calculated from the glucose content as a percentage of the theoretical glucose available in the substrates)of sugarcane bagasse from GL-ethanol pretreatment (97.7%) was higher than that from GL-H2O2 pretreatment (41.7%) after 72h hydrolysis with 18 filter paper unit (FPU)/g-cellulose for cellulase, 27,175 cellobiase units (CBU)/g-cellulose for β-glucosidase. Furthermore, about 94.1% of xylan was converted to xylose after GL-ethanol pretreatment without additional xylanase, while the xylose yield was only 29.2% after GL-H2O2 pretreatment. Scanning electron microscopy showed that GL-ethanol pretreatment could break up the fiber severely. Moreover, GL-ethanol pretreated substrate was more accessible to cellulase and more hydrophilic than that of GL-H2O2 pretreated. Therefore, GL-ethanol pretreatment is a promising method for improving the overall sugar (glucose and xylan) yield of sugarcane bagasse.

We report on a method for the determination of the herbicide atrazine in tap water samples using melamine-modified gold nanoparticles (Mel-AuNPs). If a solution containing atrazine is added to a solution of such NPs, a color change occurs from wine-red to blue. This is due to a transition from monodisperse to aggregated Mel-AuNPs and caused by strong hydrogen bonding between atrazine and melamine. The color change can be monitored by a UV–vis spectrophotometer or with bare eyes. The ratio of the absorbances at 640 and 523 nm is linearly related to the logarithm of the atrazine concentration in the 0.165 to 16.5 μM range, and (with different slope) in the 16.5 μM to 330 μM range. The detection limit of atrazine is as low as 16.5 nM (S/N = 3). The method was successfully applied to the determination of atrazine in spiked tap water and gave recoveries that ranged from 72.5 % to 102.3 %.

As a lignocellulosic material, wastepaper is a potential material for ethanol production. However, little research on the enzymatic hydrolysis of wastepaper pulp has been conducted. In this study, the enzymatic hydrolysis of different waste pulp fractions (R80 represents greater than 80-mesh wastepaper pulp, R80-180 represents the range of 80- to 180-mesh wastepaper pulp, and R180 represents smaller than 180-mesh waste paper pulp) were carried out at 50 °C, pH 4.8, for 96 h, with a substrate concentration of 5% (w/v) and cellulase loading of 18 FPU/g cellulose. In terms of the specific surface area, fiber structure, and surface morphology, R80-180 had the highest affinity to cellulase and therefore the highest glucose yield of 80.33%. R180 had the lowest glucose yield (55.36%) because of its high ash content (21.36%), which reduced the adsorption of cellulase to cellulose. The enzymatic hydrolysis of R80 mixed with R80 or R80-180 was also studied. Results indicated that adding R80-180 increased the glucose yield of R80. The highest glucose yield (82.57%) was obtained when 15% R80-180 was mixed with R80. However, the glucose content decreased when R180 was mixed with R80 because of its high ash content.

Furfural residues (FRs) is an industrial waste material with an enormous potential for bio-ethanol production. In this study, FRs were pretreated with green liquor (GL) combined with hydrogen peroxide (GL–H2O2) or ethanol (GL-ethanol). The wettability and electrostatic contributions of untreated and pretreated FRs was investigated as well as that of isolated lignin cellulolytic enzyme lignin (CEL) and cellulose. The results showed that the hydrophilicity of FRs was increased after GL–H2O2 and GL-ethanol pretreatment. Lignin is the key factor that affects the hydrophilicity of substrate. The cellulase binding for lignin was reduced due to the increase of hydrophilicity of lignin, resulting in the improvement of enzymatic hydrolysis. The electrostatic contributions was also an important factor that influenced the cellulase binding of lignin. After pretreatments, the negative charge of lignin was decreased. Accordingly, the cellulase binding capacity was reduced. This effect was more significant after the GL-ethanol pretreatment. Thus, the glucose yield of the substrate obtained from the GL-ethanol pretreatment (86.1 %) was larger than that from the GL–H2O2 pretreatment (82.2 %). Unlike the CEL, GL–H2O2 pretreatment increased the negative charge of cellulose. And the increase of negative charge improved the affinity of cellulose to cellulase via electrostatic attraction. The XPS analyses indicated that the carbonyl groups from lignin play an important role in decreasing the hydrophobicity of the substrates.