Apple replant disease(ARD)negatively affects plant growth and reduces yields in replanted orchards.In this study,biochar was applied to apple replant soil with Fusarium oxysporum.Our aim was to investigate whether bio...Apple replant disease(ARD)negatively affects plant growth and reduces yields in replanted orchards.In this study,biochar was applied to apple replant soil with Fusarium oxysporum.Our aim was to investigate whether biochar could promote plant growth and alleviate apple replant disease by reducing the growth of harmful soil microorganisms,changing soil microbial community structure and improving the soil environment.This experiment included five treatments:apple replant soil(CK),methyl bromide fumigation apple replant soil(FM),replant soil with biochar addition(2%),replant soil with F.oxysporum spore solution(8×10^(7)spores·mL^(-1)),and replant soil with biochar and F.oxysporum spore solution addition.Seedling biomass,the activity of antioxidant enzymes in the leaves and roots,and soil environmental variables were measured.Microbial community composition and community structure were analyzed using 16SrDNA and ITS2 gene sequencing.Biochar significantly reduced the abundance of F.oxysporum and increased soil microbial diversity and richness.Biochar also increased the soil enzyme activities(urease,invertase,neutral phosphatase,and catalase),the biomass(plant height,fresh weight,dry weight)and the activity of antioxidant enzymes(superoxide dismutase,peroxidase,and catalase).The root indexes of apple seedlings was also increased in replant soil by biochar.In sum,biochar promoted the growth of plants,improved the replant soil environment,and alleviated apple replant disease.展开更多
Ellagic acid(EA)is a natural antioxidant,widely present in a lot of forms’soft fruits,nuts,and other plant tissues,and helpful for promoting human health;however,its protective effect on postharvest fruit and improvi...Ellagic acid(EA)is a natural antioxidant,widely present in a lot of forms’soft fruits,nuts,and other plant tissues,and helpful for promoting human health;however,its protective effect on postharvest fruit and improving the quality index of postharvest fruit have rarely been studied.In this experiment,the strawberries were soaked in 0,100,200,300,400,and 500 mg L^(−1) EA,respectively,and the influential EA on fruit quality and the antioxidant system of strawberries were studied.Compared with the control,EA treatment can reduce the browning degree and rotting rate of strawberry fruit during storage and augment the soluble solid content(SSC).EA treatment can also increase the content of related stuff and enzyme activity in antioxidant systems;the gene expression level of polyphenol oxidase(PPO)in strawberries treated with EA was always down-regulated,correspondingly,the expression of other antioxidant enzyme genes was enhanced.Among the strawberry fruits treated with EA of different concentrations,300 mg L^(−1) EA had the best effect in the process of strawberry preservation.The results suggested that the proper concentration of exogenous EA at 300 mg L−1 could maintain strawberries’quality and enhance the antioxidant system by improving the activities of antioxidative enzymes and the ascorbateglutathione(AsA-GSH)cycle during storage.展开更多
Nitrosoglutathione(GSNO)andβ-cyclodextrin(β-CD)exhibit positive roles in regulating fruit quality.However,there are few reports about the effects of GSNO andβ-CD on enhancing storability and boosting nitric oxide(N...Nitrosoglutathione(GSNO)andβ-cyclodextrin(β-CD)exhibit positive roles in regulating fruit quality.However,there are few reports about the effects of GSNO andβ-CD on enhancing storability and boosting nitric oxide(NO),hydrogen sulfide(H2S),and phenylpropane metabolism in fruits during storage.“Xintaihong”peach were treated with 0.5,1.0,1.5mmol L−1 GSNO in 0.5%(w/v)β-CD solution(GSNO/β-CD).The effects of GSNO/β-CD on endogenous NO,H2S,and phenylpropane metabolism were investigated.Treatment with GSNO/β-CD increased the color difference of peach and inhibited the increase of respiratory intensity,weight loss,and relative conductivity.Treatment with 1.0 mmol L−1 GSNO/β-CD increased the nitric oxide synthase(NOS-like)activity and L-arginine content,thereby promoting the accumulation of endogenous NO.By improving the activities of L-cysteine desulfhydrylase(L-CD),O-acetylserine sulfur lyase(OAS-TL),serine acetyltransferase(SAT),GSNO/β-CD increased the content of endogenous H2S in peach.Treatment with GSNO/β-CD increased the activities of phenylalanine ammonia-lyase(PAL),4-coumarate-CoA ligase(4CL),and cinnamic acid-4-hydroxylase(C4H),promoted the increase of total phenols,flavonoids,and lignin in peach.These results indicated that GSNO/β-CD treatment better maintained the quality of peach by improving the metabolism of endogenous NO,H2S,and phenylpropane during storage.展开更多
In this work,a dual-size MOF-derived Co catalyst(0.2Co_(1-NPs)@NC)composed of single atoms(Co_(1))and highly dispersed nanoparticles(Co NPs)was prepared by in-situ Zn evaporation for the highperformance conversion of ...In this work,a dual-size MOF-derived Co catalyst(0.2Co_(1-NPs)@NC)composed of single atoms(Co_(1))and highly dispersed nanoparticles(Co NPs)was prepared by in-situ Zn evaporation for the highperformance conversion of lignin-derived o-methoxyphenols(lignin oil)to cyclohexanols(up to 97%yield)via cascade demethoxylation and dearomatization.Theoretical calculations elaborated that the dual-size Co catalyst exhibited a cooperative effect in the selective demethoxylation process,in which the Co NPs could initially dissociate hydrogen at lower energies while Co1remarkably facilitated the cleavage of the C_(Ar)-OCH_(3)bond.Moreover,the intramolecular hydrogen bonds formed in the omethoxy-containing phenols were found to result in a decrease in the bond energy of the C_(Ar)-OCH_(3)bond,which was more prone to be activated by the dual-size Co sites.Notably,the pre-hydrogenated intermediate(e.g.,2-methoxycyclohexanol from guaiacol)is difficult to undergo demethoxylation,indicating that the selective C_(Ar)-OCH_(3)bond cleavage is a prerequisite for the synthesis of cyclohexanols.The 0.2Co_(1-NPs)@NC catalyst was highly recyclable with a neglect decline in activity during five consecutive cycles.This cooperative catalytic strategy based on the metal size effect opens new avenues for biomass upgrading via enhanced C-O bond cleavage of high selectivity.展开更多
Resistant starch (RS) is the undigested starch that passes through the small intestine to the large intestine. As a functional low calorie additive, it has special applications in the food industry. Rapid visco anal...Resistant starch (RS) is the undigested starch that passes through the small intestine to the large intestine. As a functional low calorie additive, it has special applications in the food industry. Rapid visco analysis (RVA) and the Brabender farinograph were used to study the pasting properties and the viscoelasticity of blends of RS (RS3 and RS2) and three wheat flours. The wheat flours represented strong gluten wheat (SGW), intermediate gluten wheat (IGW), and weak gluten wheat (WGW) flours, at different levels of RS substitution (0, 5, 10, 15, and 20%). The influence of RS3 on the control wheat flours and RS-wheat flour blends were consistent with those of RS2. The peak, trough, and final viscosities of RS3-wheat flour blends were higher than those of the corresponding RS2-wheat flour blends. The peak, trough, breakdown, final, and setback viscosities ofwheat-RS blends decreased with an increase in resistant starch contents from 0 to 20% in the blends. The 0-20% RS-wheat flour blends were all able to form doughs. The dough development times, dough stabilities, dough breakdown times, and farinograph quality numbers for the RS-wheat flour blends decreased as the RS proportion in the blends increased. The values for RS-SGW flour blends were the highest, followed by RS-IGW and then RS-WGW flour blends. The water absorption values for RS-wheat flour blends and the mixing tolerance index for RS-WGW flour blends were found to increase significantly with an increasing proportion of RS from 0 to 20%, but the mixing tolerance index for RS-SGW and RS-IGW flour blends showed no significant differences amongst the different ratios. Correlation analysis showed that the Farinograph quality number was highly positively correlated with dough breakdown time, dough stability, and dough development time (r= 1.000, 0.958, 0.894), and highly negatively correlated with the mixing tolerance index (r =-0.890). Data from this study can be used for the development of dough-based products. It also provides a basis for RS-wheat flour blends and quality evaluation in the food industry.展开更多
Iron(Ⅲ)-doped nanostructure TiO2-coated SiO2 (TiO2/SiO2) particles were prepared using the layer-by-layer assembly technique and their photocatalytic property was studied. TiO2 colloids were synthesized employing...Iron(Ⅲ)-doped nanostructure TiO2-coated SiO2 (TiO2/SiO2) particles were prepared using the layer-by-layer assembly technique and their photocatalytic property was studied. TiO2 colloids were synthesized employing the sol-gel method with TiChas a precursor. The samples were characterized by Fourier transform infrared spectroscopy (FTIR), SEM, EDS, XPS, and XRD. The experimental results show that TiO2 nanopowders on the surface of SiO2 particles are well distributed, the amount of TiO2 is increased with the adding of coating layers, the pure anatase-TiO2 coating layers are synthesized at 500℃, and the photocatalytic activity of Fe^3+-doped TiO2/SiO2 is higher than that of undoped TiO2/SiO2.展开更多
This article investigates the effects of nitric oxide (NO) on alcoholic fermentation and the qualities of Chinese Winter Jujube during storage, and explores the action mechanisms of browning and softening of fruits ...This article investigates the effects of nitric oxide (NO) on alcoholic fermentation and the qualities of Chinese Winter Jujube during storage, and explores the action mechanisms of browning and softening of fruits to provide theoretical proofs for using NO in the storage of Chinese Winter Jujube. Chinese Winter Jujube fruits were fumigated with different concentrations of NO gas (0, 10, 20, 30 μL L^-1) under anaerobic conditions and stored at 22±1℃ and 4± 1℃. The changes in appearance qualities, the contents of pyruvate, ethanol, acetaldehyde, and the activities of alcohol dehydrogenase (ADH) and lactate dehydrogenase (LDH) were investigated. The contents of pyruvate, ethanol, and acetaldehyde were significantly reduced, and the peak of pyruvate content was delayed by 20 μL L^-1 NO. The activities of ADH and LDH in 20 μL L^-1 NO treated fruits were also significantly inhibited. However, the alcoholic fermentation and softening of Chinese Winter Jujube fruits were promoted by 30 μL L^-1 NO during storage. The results indicated that 20 μL L^-1 NO could mitigate the injury of ethanol on Chinese Winter Jujube and effectively delay the browning and softening of fruits during storage.展开更多
Cu^2+-doped nanostructured TiO2-coated SiO2 (TiO2/SiO2) particles were prepared by the layer-by-layer assembly technique and their photocatalytic property was studied. TiO2 colloids were synthesized by the sol-gel ...Cu^2+-doped nanostructured TiO2-coated SiO2 (TiO2/SiO2) particles were prepared by the layer-by-layer assembly technique and their photocatalytic property was studied. TiO2 colloids were synthesized by the sol-gel method using TiOSO4 as a precursor. The experimental results showed that TiO2 nanopowders on the surface of SiO2 particles were well distributed and compact. The amount of TiO2 increased with the increase in coating layers. The shell structure appeared to be composed of anatase titania nanocrystals at 550℃. The 2-layer coated TiO2 particles on the surface showed a higher degradation rate compared with all the different-layer samples. The photocatalytic activity of Cu^2+-doped TiO2/SiO2 was higher than that ofundoped TiO2/SiO2. The optimum dopant content was about 0.10wt%.展开更多
In this work, 25 3-O-β-chacotriosyl ursolic acid derivatives were employed to achieve the highly reliable and predictive 3 D-QSAR models by Co MFA and Co MSIA methods, respectively. The predictive capabilities of two...In this work, 25 3-O-β-chacotriosyl ursolic acid derivatives were employed to achieve the highly reliable and predictive 3 D-QSAR models by Co MFA and Co MSIA methods, respectively. The predictive capabilities of two constructed CoMFA and CoMSIA models were verified by the leave-one-out cross-validation method. The results showed that the cross-validated coefficient(q2) and non-cross-validated coefficient(R2) were 0.559, 0.981 in the CoMFA model and 0.696, 0.978 in the CoM SIA model, respectively, which suggests that these two models are robust and have good exterior predictive capabilities. Furthermore, based on the contour maps information of two models, ten novel inhibitors with higher inhibitory potency were designed, and the quantum chemical calculation of density functional theory(DFT) was performed to investigate the mechanism why the designed molecules have stronger inhibitory activity than the lead compound. The calculations show that the C-50 position of lead compound is a key active site for the enhancement of inhibitory activity, and it should be introduced into the large electron withdrawing group, which would result in generating potent and selective H5 N1 entry inhibitors. We expect that the results in this paper could provide important information to develop new potent H5 N1 entry inhibitors.展开更多
Titanium dioxide (TiO2) films with rod-like and sphere-like TiO2 particles were prepared on glass slides employing the sol-gel method. The shape and size of TiO2 particles were controlled using different concentrati...Titanium dioxide (TiO2) films with rod-like and sphere-like TiO2 particles were prepared on glass slides employing the sol-gel method. The shape and size of TiO2 particles were controlled using different concentrations of sodium dodecylbenzensulfonate (SDBS). By increasing the mole ratio of SDBS, the shape of TiO2 particles transformed from rod-like to sphere-like. Also, the size of TiO2 particles became gradually smaller. Then, the size became bigger when an excess amount of SDBS was added. The films were mainly composed of anatase titania and the relative content of anatase increased with the increasing amount of SDBS. The photocatalytic activity of the TiO2 films that were added with SDBS was higher than that without SDBS. When the concentration of SDBS was 8.0 at%, the sample exhibited the best photocatalytic activity.展开更多
Ni-based phosphides(NiPx)composed of earth-abundant elements are promising cocatalysts to replace noble metals for photocatalytic H2 evolution reaction(HER).A safe,energy-saving,and compositioncontrollable synthesis o...Ni-based phosphides(NiPx)composed of earth-abundant elements are promising cocatalysts to replace noble metals for photocatalytic H2 evolution reaction(HER).A safe,energy-saving,and compositioncontrollable synthesis of NiPx is still highly desired.A facile and mild solvothermal process was developed for the first time for selective synthesis of a series of NiPx,including Ni,Ni12P5,Ni2P/Ni12P5,Ni/Ni2P and Ni2P,through controlling the dosage of NaBH4 and NaH2PO2.The phosphidation process was mainly composed of(1)a sequential reduction of Ni2+to Nj0 and(H2PO2)-to P(around the formed Ni0)triggered by NaBH4,and(2)a final phosphidation between Nj0 and the in situ generated P atoms.The photocatalytic HER performance of g-C3N4 can be substantially improved with the decoration of NiPx(3 wt%)as the separation of photoinduced charge carriers can be promoted and some active sites with low over-potential for HER can be introduced.The cocatalytic efficiency of NiPx is mainly determined by P content.Ni2P with a high ratio of P consequently exhibits the highest HER performance(215.1 umol g-1 h-1),which is almost six times higher than that of the pristine g-C3N4(35.6 umol g-1 h-1).Thus,as for the cocatalyst based on Ni phosphides,Ni2P is the preferable crystal phase and more efforts should be devoted to Ni2P to further optimize its structure,texture,and morphology in future works.展开更多
Introduction The formation of gelatin-containing mieroemulsionbased gels(MBGs) was first described in 1986 and the physical/structural characterization was carried out by a number of groups with a variety of techni...Introduction The formation of gelatin-containing mieroemulsionbased gels(MBGs) was first described in 1986 and the physical/structural characterization was carried out by a number of groups with a variety of techniques including tracer diffusion, electrical conductivity, NMR, X-ray and small angle neutron scattering. The MBGs were proposed to comprise an extensive, rigid, interconnected network of gelatin/water rods stabilized by a monolayer of surfactant, in coexistence with a po- pulation of conventional W/O microemulsion droplets.展开更多
Ag^+ -doped ZnS nanocrystals surface-capped with thiourea (expressed as ZnS: Ag/thiourea) were synthesized through sol-gel method with thiourea as a surface modifier and characterized by X-ray diffraction(XRD), ...Ag^+ -doped ZnS nanocrystals surface-capped with thiourea (expressed as ZnS: Ag/thiourea) were synthesized through sol-gel method with thiourea as a surface modifier and characterized by X-ray diffraction(XRD), transmission electron microscope(TEM), X-ray fluorescence spectrum(XRF), infrared spectrum (IR), UV-Vis absorption spectrum( UV-Vis), and photoluminescence spectrum(PL). The results show that Ag^+ ions are doped in ZnS nanocrystals, and the sulfur atoms in thiourea molecules coordinate with metal ions on the surface of the nanocrystals. The spherical ZnS: Ag/thiourea nanocrystals with an average diameter of 5 nm have good fluorescent characteristics, and therefore have great potential for use in molecular assembly and novel luminescence materials.展开更多
The novel sulfonated polyimide membranes were successfully synthesized by thermal imidization with monomers of 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), 4,4'-diamino- diphenyl ether-2,2'-disul...The novel sulfonated polyimide membranes were successfully synthesized by thermal imidization with monomers of 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), 4,4'-diamino- diphenyl ether-2,2'-disulfonic acid (SODA) and 3,3 '-diaminochalcone (3DAC). Photosensitive chalcone moiety was introduced to the main chain of copolymers, and the photocrosslinking of resulting copolymer in aqueous electrolyte was attempted. A series of sulfonated copolyimide precursors containing chalcone functional groups in the main chain were prepared with different sulfonation degrees by controlling the molar ratio of SODA, 6FDA and 3DAC. The polymer membranes were prepared from these sulfonated aromatic precursors by solution casting and subsequent thermal imidization. The crosslinking with UV irradiation was attempted in the presence or absence of distilled water. The characterizations of the resulting membrane such as the ion-exchange capacity, water absorption and ionic conductivity were performed with respect to the copolymer compositions and the photocrosslinking conditions.展开更多
To provide hints for the design of new acetylcholinesterase(ACh E) inhibitors with higher potency and specificity, the binding modes of novel heterodimers comprised of donepezil and huperzine A fragments with ACh E ...To provide hints for the design of new acetylcholinesterase(ACh E) inhibitors with higher potency and specificity, the binding modes of novel heterodimers comprised of donepezil and huperzine A fragments with ACh E were explored by employing the docking simulations. The results show that the binding mode of S-17b(the most potent inhibitor in Ref. 2, i.e., Bioorg. Med. Chem. 2013, 21, 676-683) is clearly different from that of donepezil, while the binding modes of other heterodimers in Ref. 2 are the same as that of donepezil. In addition, based on the binding mode and structure modification of S-17 b, two novel inhibitors(S-17b1 and S-17bb1) with much higher inhibitory potency than S-17 b were obtained. Our design strategy was to replace the hupyridone moiety of S-17 b with the bulky group, and to replace the dimethoxyindanone moiety of S-17 b with more hydrophobic and bulky group with a highly positive charge, which would result in generating potent and selective AChE inhibitors.展开更多
Acute inflammation is a central component in the progression of spinal cord injury(SCI).Anti-inflammatory drugs used in the clinic are often administered systemically at high doses,which can paradoxically increase inf...Acute inflammation is a central component in the progression of spinal cord injury(SCI).Anti-inflammatory drugs used in the clinic are often administered systemically at high doses,which can paradoxically increase inflammation and result in drug toxicity.A cluster-like mesoporous silica/arctigenin/CAQK composite(MSN-FC@ARCG)drug delivery system was designed to avoid systemic side effects of high-dose therapy by enabling site-specific drug delivery to the spinal cord.In this nanosystem,mesoporous silica was modified with the FITC fluorescent molecule and CAQK peptides that target brain injury and SCI sites.The size of the nanocarrier was kept at approximately 100 nm to enable penetration of the blood–brain barrier.Arctigenin,a Chinese herbal medicine,was loaded into the nanosystem to reduce inflammation.The in vivo results showed that MSN-FC@ARC-G could attenuate inflammation at the injury site.Behavior and morphology experiments suggested that MSN-FC@ARC-G could diminish local microenvironment damage,especially reducing the expression of interleukin-17(IL-17) and IL-17-related inflammatory factors,inhibiting the activation of astrocytes,thus protecting neurons and accelerating the recovery of SCI.Our study demonstrated that this novel,silica-based drug delivery system has promising potential for clinical application in SCI therapy.展开更多
UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing g...UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing group -CF3 and -C3F7 on β-diketonate made the strongest absorption peak red-shift and the lowest energy absorption blue-shied. Introduction of -OC2H5 on the benzene or pyridine ring made the lowest energy absorption blue-shift. When the -C2H3 was introduced on the benzene or pyridine ring, the lowest energy absorption was red-shifted. Introduction of electron-donating group on β-diketonate can enlarge their nonlinear optical properties. On the contrary, the introduction of electron-drawing group dropped it down.展开更多
The effects of nitric oxide (NO) and exogenous ethylene on ethylene biosynthesis in harvested Feicheng peaches were studied. The antagonistic actions between NO and exogenous ethylene was also investigated. The Feic...The effects of nitric oxide (NO) and exogenous ethylene on ethylene biosynthesis in harvested Feicheng peaches were studied. The antagonistic actions between NO and exogenous ethylene was also investigated. The Feicheng peaches were fumigated with 10μL L^-1 NO, 1 000 μL L^-1 ethylene, or 10 μL L^-1 NO plus 1 000 μL L^-1 ethylene for 3 h. The results suggested that application of exogenous ethylene promoted the biosynthesis of endogenous ethylene in peach fruit. The treatment with NO remarkably inhibited the biosynthesis of ethylene by significantly reducing the activities of ACC synthase (ACS) and ACC oxidase (ACO). Ethylene biosynthesis in the fruits treated with both NO and exogenous ethylene was lower than that in fruits treated with exogenous ethylene alone but higher than that in fruits treated with NO alone, suggesting that there were antagonistic actions between NO and exogenous ethylene. NO could inhibit the biosynthesis of ethylene and the catalysis of exogenous ethylene during ethylene biosynthesis in peach fruits.展开更多
2-Oxo-butyric acid salicylacylhydrazone dibenzyltin(IV) complexes 1 {[o-OHC6H4(O)C=N-N=C(Et)COO](CH3OH)[(C6H5CH2)2Sn]}2 and 2 {[o-OH-C6H4(O)C=N-N=C(Et)-COO](CH3OH)[(2,4-Cl2C6H3CH2)2Sn]}2 have been sy...2-Oxo-butyric acid salicylacylhydrazone dibenzyltin(IV) complexes 1 {[o-OHC6H4(O)C=N-N=C(Et)COO](CH3OH)[(C6H5CH2)2Sn]}2 and 2 {[o-OH-C6H4(O)C=N-N=C(Et)-COO](CH3OH)[(2,4-Cl2C6H3CH2)2Sn]}2 have been synthesized. The complexes were characterized by IR, 1H, 13C and 119Sn NMR spectra, elemental analysis and thermal stability analysis, and the crystal structures were determined by X-ray diffraction. The crystal of complex 1 belongs to triclinic system, space group P1 with a = 8.9121(6), b = 10.3875(7), c = 14.5658(10) ?, α = 89.534(5), β = 86.790(5), γ = 70.103(6)°, Z = 1, V = 1265.85(15) ?3, Dc = 1.488 Mg·m^(-3), m(Mo Kα) = 1.047 mm-1, F(000) = 576, R = 0.0466 and w R = 0.1054. The crystal of complex 2 belongs to monoclinic system, space group P21/n, a = 12.7165(10), b = 17.8466(14), c = 12.8538(10) ?, β = 95.1310(10)°, Z = 2, V = 2905.4(4) ?~3, Dc = 1.612 Mg·m^(-3), m(Mo Kα) = 1.286 mm-1, F(000) = 1408, R = 0.0369 and w R = 0.0958. In vitro antitumor activities of both complexes were evaluated by the 3-(4,5-dimethylthiazoly-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay against three human cancer cell lines(NCI-H460, HepG2, MCF7) and one human cell line(HL7702). Two complexes exhibited strong antitumor activity, and then they were expected after further chemical optimization of candidate compounds as anti-cancer drugs. The interaction between complexes and calf thymus DNA were studied by EB fluorescent probe. The interactions of the two complexes with calf thymus DNA were intercalation.展开更多
基金supported by the earmarked fund for National Natural Science Foundation of China(Grant No.31801816)National Modern Agro-industry Technology Research System(Grant No.CARS-27)Taishan scholar funded project(Grant No.TS20190923)。
文摘Apple replant disease(ARD)negatively affects plant growth and reduces yields in replanted orchards.In this study,biochar was applied to apple replant soil with Fusarium oxysporum.Our aim was to investigate whether biochar could promote plant growth and alleviate apple replant disease by reducing the growth of harmful soil microorganisms,changing soil microbial community structure and improving the soil environment.This experiment included five treatments:apple replant soil(CK),methyl bromide fumigation apple replant soil(FM),replant soil with biochar addition(2%),replant soil with F.oxysporum spore solution(8×10^(7)spores·mL^(-1)),and replant soil with biochar and F.oxysporum spore solution addition.Seedling biomass,the activity of antioxidant enzymes in the leaves and roots,and soil environmental variables were measured.Microbial community composition and community structure were analyzed using 16SrDNA and ITS2 gene sequencing.Biochar significantly reduced the abundance of F.oxysporum and increased soil microbial diversity and richness.Biochar also increased the soil enzyme activities(urease,invertase,neutral phosphatase,and catalase),the biomass(plant height,fresh weight,dry weight)and the activity of antioxidant enzymes(superoxide dismutase,peroxidase,and catalase).The root indexes of apple seedlings was also increased in replant soil by biochar.In sum,biochar promoted the growth of plants,improved the replant soil environment,and alleviated apple replant disease.
基金the National Natural Science Foundation of China,Grant Number 31800581.
文摘Ellagic acid(EA)is a natural antioxidant,widely present in a lot of forms’soft fruits,nuts,and other plant tissues,and helpful for promoting human health;however,its protective effect on postharvest fruit and improving the quality index of postharvest fruit have rarely been studied.In this experiment,the strawberries were soaked in 0,100,200,300,400,and 500 mg L^(−1) EA,respectively,and the influential EA on fruit quality and the antioxidant system of strawberries were studied.Compared with the control,EA treatment can reduce the browning degree and rotting rate of strawberry fruit during storage and augment the soluble solid content(SSC).EA treatment can also increase the content of related stuff and enzyme activity in antioxidant systems;the gene expression level of polyphenol oxidase(PPO)in strawberries treated with EA was always down-regulated,correspondingly,the expression of other antioxidant enzyme genes was enhanced.Among the strawberry fruits treated with EA of different concentrations,300 mg L^(−1) EA had the best effect in the process of strawberry preservation.The results suggested that the proper concentration of exogenous EA at 300 mg L−1 could maintain strawberries’quality and enhance the antioxidant system by improving the activities of antioxidative enzymes and the ascorbateglutathione(AsA-GSH)cycle during storage.
基金supported by the National Natural Science Foundation of China(32071808).
文摘Nitrosoglutathione(GSNO)andβ-cyclodextrin(β-CD)exhibit positive roles in regulating fruit quality.However,there are few reports about the effects of GSNO andβ-CD on enhancing storability and boosting nitric oxide(NO),hydrogen sulfide(H2S),and phenylpropane metabolism in fruits during storage.“Xintaihong”peach were treated with 0.5,1.0,1.5mmol L−1 GSNO in 0.5%(w/v)β-CD solution(GSNO/β-CD).The effects of GSNO/β-CD on endogenous NO,H2S,and phenylpropane metabolism were investigated.Treatment with GSNO/β-CD increased the color difference of peach and inhibited the increase of respiratory intensity,weight loss,and relative conductivity.Treatment with 1.0 mmol L−1 GSNO/β-CD increased the nitric oxide synthase(NOS-like)activity and L-arginine content,thereby promoting the accumulation of endogenous NO.By improving the activities of L-cysteine desulfhydrylase(L-CD),O-acetylserine sulfur lyase(OAS-TL),serine acetyltransferase(SAT),GSNO/β-CD increased the content of endogenous H2S in peach.Treatment with GSNO/β-CD increased the activities of phenylalanine ammonia-lyase(PAL),4-coumarate-CoA ligase(4CL),and cinnamic acid-4-hydroxylase(C4H),promoted the increase of total phenols,flavonoids,and lignin in peach.These results indicated that GSNO/β-CD treatment better maintained the quality of peach by improving the metabolism of endogenous NO,H2S,and phenylpropane during storage.
基金the Guizhou Provincial S&T Project(ZK[2022]011)the National Natural Science Foundation of China(21908033,21922513)+1 种基金the Natural Science Foundation of Guangxi Zhuang Autonomous Region(2020GXNSFAA297072)the Fok Ying-Tong Education Foundation(161030)。
文摘In this work,a dual-size MOF-derived Co catalyst(0.2Co_(1-NPs)@NC)composed of single atoms(Co_(1))and highly dispersed nanoparticles(Co NPs)was prepared by in-situ Zn evaporation for the highperformance conversion of lignin-derived o-methoxyphenols(lignin oil)to cyclohexanols(up to 97%yield)via cascade demethoxylation and dearomatization.Theoretical calculations elaborated that the dual-size Co catalyst exhibited a cooperative effect in the selective demethoxylation process,in which the Co NPs could initially dissociate hydrogen at lower energies while Co1remarkably facilitated the cleavage of the C_(Ar)-OCH_(3)bond.Moreover,the intramolecular hydrogen bonds formed in the omethoxy-containing phenols were found to result in a decrease in the bond energy of the C_(Ar)-OCH_(3)bond,which was more prone to be activated by the dual-size Co sites.Notably,the pre-hydrogenated intermediate(e.g.,2-methoxycyclohexanol from guaiacol)is difficult to undergo demethoxylation,indicating that the selective C_(Ar)-OCH_(3)bond cleavage is a prerequisite for the synthesis of cyclohexanols.The 0.2Co_(1-NPs)@NC catalyst was highly recyclable with a neglect decline in activity during five consecutive cycles.This cooperative catalytic strategy based on the metal size effect opens new avenues for biomass upgrading via enhanced C-O bond cleavage of high selectivity.
基金the National Natural Science Foundation of China (30671270)the National High Technology R & D Program of China (2006AA100101).
文摘Resistant starch (RS) is the undigested starch that passes through the small intestine to the large intestine. As a functional low calorie additive, it has special applications in the food industry. Rapid visco analysis (RVA) and the Brabender farinograph were used to study the pasting properties and the viscoelasticity of blends of RS (RS3 and RS2) and three wheat flours. The wheat flours represented strong gluten wheat (SGW), intermediate gluten wheat (IGW), and weak gluten wheat (WGW) flours, at different levels of RS substitution (0, 5, 10, 15, and 20%). The influence of RS3 on the control wheat flours and RS-wheat flour blends were consistent with those of RS2. The peak, trough, and final viscosities of RS3-wheat flour blends were higher than those of the corresponding RS2-wheat flour blends. The peak, trough, breakdown, final, and setback viscosities ofwheat-RS blends decreased with an increase in resistant starch contents from 0 to 20% in the blends. The 0-20% RS-wheat flour blends were all able to form doughs. The dough development times, dough stabilities, dough breakdown times, and farinograph quality numbers for the RS-wheat flour blends decreased as the RS proportion in the blends increased. The values for RS-SGW flour blends were the highest, followed by RS-IGW and then RS-WGW flour blends. The water absorption values for RS-wheat flour blends and the mixing tolerance index for RS-WGW flour blends were found to increase significantly with an increasing proportion of RS from 0 to 20%, but the mixing tolerance index for RS-SGW and RS-IGW flour blends showed no significant differences amongst the different ratios. Correlation analysis showed that the Farinograph quality number was highly positively correlated with dough breakdown time, dough stability, and dough development time (r= 1.000, 0.958, 0.894), and highly negatively correlated with the mixing tolerance index (r =-0.890). Data from this study can be used for the development of dough-based products. It also provides a basis for RS-wheat flour blends and quality evaluation in the food industry.
基金the Nationnal Natural Science Foundation of China (No. 50342016).
文摘Iron(Ⅲ)-doped nanostructure TiO2-coated SiO2 (TiO2/SiO2) particles were prepared using the layer-by-layer assembly technique and their photocatalytic property was studied. TiO2 colloids were synthesized employing the sol-gel method with TiChas a precursor. The samples were characterized by Fourier transform infrared spectroscopy (FTIR), SEM, EDS, XPS, and XRD. The experimental results show that TiO2 nanopowders on the surface of SiO2 particles are well distributed, the amount of TiO2 is increased with the adding of coating layers, the pure anatase-TiO2 coating layers are synthesized at 500℃, and the photocatalytic activity of Fe^3+-doped TiO2/SiO2 is higher than that of undoped TiO2/SiO2.
文摘This article investigates the effects of nitric oxide (NO) on alcoholic fermentation and the qualities of Chinese Winter Jujube during storage, and explores the action mechanisms of browning and softening of fruits to provide theoretical proofs for using NO in the storage of Chinese Winter Jujube. Chinese Winter Jujube fruits were fumigated with different concentrations of NO gas (0, 10, 20, 30 μL L^-1) under anaerobic conditions and stored at 22±1℃ and 4± 1℃. The changes in appearance qualities, the contents of pyruvate, ethanol, acetaldehyde, and the activities of alcohol dehydrogenase (ADH) and lactate dehydrogenase (LDH) were investigated. The contents of pyruvate, ethanol, and acetaldehyde were significantly reduced, and the peak of pyruvate content was delayed by 20 μL L^-1 NO. The activities of ADH and LDH in 20 μL L^-1 NO treated fruits were also significantly inhibited. However, the alcoholic fermentation and softening of Chinese Winter Jujube fruits were promoted by 30 μL L^-1 NO during storage. The results indicated that 20 μL L^-1 NO could mitigate the injury of ethanol on Chinese Winter Jujube and effectively delay the browning and softening of fruits during storage.
基金the Department of Education of Hebei Province, China (No.2005362)
文摘Cu^2+-doped nanostructured TiO2-coated SiO2 (TiO2/SiO2) particles were prepared by the layer-by-layer assembly technique and their photocatalytic property was studied. TiO2 colloids were synthesized by the sol-gel method using TiOSO4 as a precursor. The experimental results showed that TiO2 nanopowders on the surface of SiO2 particles were well distributed and compact. The amount of TiO2 increased with the increase in coating layers. The shell structure appeared to be composed of anatase titania nanocrystals at 550℃. The 2-layer coated TiO2 particles on the surface showed a higher degradation rate compared with all the different-layer samples. The photocatalytic activity of Cu^2+-doped TiO2/SiO2 was higher than that ofundoped TiO2/SiO2. The optimum dopant content was about 0.10wt%.
基金Supported by the Natural Science Foundation of Guangxi Province(Nos.2013GXNSFAA019019 and 2013GXNSFAA019041)
文摘In this work, 25 3-O-β-chacotriosyl ursolic acid derivatives were employed to achieve the highly reliable and predictive 3 D-QSAR models by Co MFA and Co MSIA methods, respectively. The predictive capabilities of two constructed CoMFA and CoMSIA models were verified by the leave-one-out cross-validation method. The results showed that the cross-validated coefficient(q2) and non-cross-validated coefficient(R2) were 0.559, 0.981 in the CoMFA model and 0.696, 0.978 in the CoM SIA model, respectively, which suggests that these two models are robust and have good exterior predictive capabilities. Furthermore, based on the contour maps information of two models, ten novel inhibitors with higher inhibitory potency were designed, and the quantum chemical calculation of density functional theory(DFT) was performed to investigate the mechanism why the designed molecules have stronger inhibitory activity than the lead compound. The calculations show that the C-50 position of lead compound is a key active site for the enhancement of inhibitory activity, and it should be introduced into the large electron withdrawing group, which would result in generating potent and selective H5 N1 entry inhibitors. We expect that the results in this paper could provide important information to develop new potent H5 N1 entry inhibitors.
基金supported by the Foundation of the Department of Education of Hebei Province, China (No. 2005362)the Foundation of Hebei Normal University (L2008K02)
文摘Titanium dioxide (TiO2) films with rod-like and sphere-like TiO2 particles were prepared on glass slides employing the sol-gel method. The shape and size of TiO2 particles were controlled using different concentrations of sodium dodecylbenzensulfonate (SDBS). By increasing the mole ratio of SDBS, the shape of TiO2 particles transformed from rod-like to sphere-like. Also, the size of TiO2 particles became gradually smaller. Then, the size became bigger when an excess amount of SDBS was added. The films were mainly composed of anatase titania and the relative content of anatase increased with the increasing amount of SDBS. The photocatalytic activity of the TiO2 films that were added with SDBS was higher than that without SDBS. When the concentration of SDBS was 8.0 at%, the sample exhibited the best photocatalytic activity.
基金financially supported by the Natural Science Foundation of Anhui Province for Distinguished Young Scholars(No.1808085J24)the Natural Science Foundation of Anhui Province(No.1808085MB45)+1 种基金the Natural Science Foundation of Educational Committee of Anhui Province(No.KJ2018A0671,KJ2018A0387)the National Natural Science Foundation of China(Nos.21473066,51772118,21603002)。
文摘Ni-based phosphides(NiPx)composed of earth-abundant elements are promising cocatalysts to replace noble metals for photocatalytic H2 evolution reaction(HER).A safe,energy-saving,and compositioncontrollable synthesis of NiPx is still highly desired.A facile and mild solvothermal process was developed for the first time for selective synthesis of a series of NiPx,including Ni,Ni12P5,Ni2P/Ni12P5,Ni/Ni2P and Ni2P,through controlling the dosage of NaBH4 and NaH2PO2.The phosphidation process was mainly composed of(1)a sequential reduction of Ni2+to Nj0 and(H2PO2)-to P(around the formed Ni0)triggered by NaBH4,and(2)a final phosphidation between Nj0 and the in situ generated P atoms.The photocatalytic HER performance of g-C3N4 can be substantially improved with the decoration of NiPx(3 wt%)as the separation of photoinduced charge carriers can be promoted and some active sites with low over-potential for HER can be introduced.The cocatalytic efficiency of NiPx is mainly determined by P content.Ni2P with a high ratio of P consequently exhibits the highest HER performance(215.1 umol g-1 h-1),which is almost six times higher than that of the pristine g-C3N4(35.6 umol g-1 h-1).Thus,as for the cocatalyst based on Ni phosphides,Ni2P is the preferable crystal phase and more efforts should be devoted to Ni2P to further optimize its structure,texture,and morphology in future works.
基金Supported by the Natural Science Foundation of Shandong Province in China(No.Y2003B01).
文摘Introduction The formation of gelatin-containing mieroemulsionbased gels(MBGs) was first described in 1986 and the physical/structural characterization was carried out by a number of groups with a variety of techniques including tracer diffusion, electrical conductivity, NMR, X-ray and small angle neutron scattering. The MBGs were proposed to comprise an extensive, rigid, interconnected network of gelatin/water rods stabilized by a monolayer of surfactant, in coexistence with a po- pulation of conventional W/O microemulsion droplets.
基金This work was funded by Natural Science Foundation of Fujian Province (No. 2008J0227) and Science and Technology Office of Fujian Province (No. 2007F5030),
基金Supported by the Science Foundation of Education Department of Fujian Province(JA03043)the Science Foundation ofDepartment of Science and Technology of Fujian Province(2005 K011).
文摘Ag^+ -doped ZnS nanocrystals surface-capped with thiourea (expressed as ZnS: Ag/thiourea) were synthesized through sol-gel method with thiourea as a surface modifier and characterized by X-ray diffraction(XRD), transmission electron microscope(TEM), X-ray fluorescence spectrum(XRF), infrared spectrum (IR), UV-Vis absorption spectrum( UV-Vis), and photoluminescence spectrum(PL). The results show that Ag^+ ions are doped in ZnS nanocrystals, and the sulfur atoms in thiourea molecules coordinate with metal ions on the surface of the nanocrystals. The spherical ZnS: Ag/thiourea nanocrystals with an average diameter of 5 nm have good fluorescent characteristics, and therefore have great potential for use in molecular assembly and novel luminescence materials.
基金Funded by the New & Renewable Energy R&D Program(2009T100100606) under the Ministry of Knowledge Economy of Koreathe National Research Foundation of Korea (NRF) through the Human Resource Training Project for Regional Innovation
文摘The novel sulfonated polyimide membranes were successfully synthesized by thermal imidization with monomers of 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), 4,4'-diamino- diphenyl ether-2,2'-disulfonic acid (SODA) and 3,3 '-diaminochalcone (3DAC). Photosensitive chalcone moiety was introduced to the main chain of copolymers, and the photocrosslinking of resulting copolymer in aqueous electrolyte was attempted. A series of sulfonated copolyimide precursors containing chalcone functional groups in the main chain were prepared with different sulfonation degrees by controlling the molar ratio of SODA, 6FDA and 3DAC. The polymer membranes were prepared from these sulfonated aromatic precursors by solution casting and subsequent thermal imidization. The crosslinking with UV irradiation was attempted in the presence or absence of distilled water. The characterizations of the resulting membrane such as the ion-exchange capacity, water absorption and ionic conductivity were performed with respect to the copolymer compositions and the photocrosslinking conditions.
基金Supported by the Natural Science Foundation of Guangxi Province(Nos.2013GXNSFAA019019 and 2013GXNSFAA019041)
文摘To provide hints for the design of new acetylcholinesterase(ACh E) inhibitors with higher potency and specificity, the binding modes of novel heterodimers comprised of donepezil and huperzine A fragments with ACh E were explored by employing the docking simulations. The results show that the binding mode of S-17b(the most potent inhibitor in Ref. 2, i.e., Bioorg. Med. Chem. 2013, 21, 676-683) is clearly different from that of donepezil, while the binding modes of other heterodimers in Ref. 2 are the same as that of donepezil. In addition, based on the binding mode and structure modification of S-17 b, two novel inhibitors(S-17b1 and S-17bb1) with much higher inhibitory potency than S-17 b were obtained. Our design strategy was to replace the hupyridone moiety of S-17 b with the bulky group, and to replace the dimethoxyindanone moiety of S-17 b with more hydrophobic and bulky group with a highly positive charge, which would result in generating potent and selective AChE inhibitors.
基金supported by the National Natural Science Foundation of China(Nos.31670969,51302089,and 31571030)the Fundamental Research Funds for the Central Universities(No.21617428)+3 种基金Key Program of Traditional Chinese Medicine of Guangdong Province(No.20173018)The Science and Technology Program of Jiangmen City of China(No.2017A2004)Natural Science Foundation of Guangdong Province(No.2018A030313576)Science and Technology Program of Guangzhou(No.201803010001)
文摘Acute inflammation is a central component in the progression of spinal cord injury(SCI).Anti-inflammatory drugs used in the clinic are often administered systemically at high doses,which can paradoxically increase inflammation and result in drug toxicity.A cluster-like mesoporous silica/arctigenin/CAQK composite(MSN-FC@ARCG)drug delivery system was designed to avoid systemic side effects of high-dose therapy by enabling site-specific drug delivery to the spinal cord.In this nanosystem,mesoporous silica was modified with the FITC fluorescent molecule and CAQK peptides that target brain injury and SCI sites.The size of the nanocarrier was kept at approximately 100 nm to enable penetration of the blood–brain barrier.Arctigenin,a Chinese herbal medicine,was loaded into the nanosystem to reduce inflammation.The in vivo results showed that MSN-FC@ARC-G could attenuate inflammation at the injury site.Behavior and morphology experiments suggested that MSN-FC@ARC-G could diminish local microenvironment damage,especially reducing the expression of interleukin-17(IL-17) and IL-17-related inflammatory factors,inhibiting the activation of astrocytes,thus protecting neurons and accelerating the recovery of SCI.Our study demonstrated that this novel,silica-based drug delivery system has promising potential for clinical application in SCI therapy.
基金supported by the National Natural Science Foundation of China(21172161)
文摘UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing group -CF3 and -C3F7 on β-diketonate made the strongest absorption peak red-shift and the lowest energy absorption blue-shied. Introduction of -OC2H5 on the benzene or pyridine ring made the lowest energy absorption blue-shift. When the -C2H3 was introduced on the benzene or pyridine ring, the lowest energy absorption was red-shifted. Introduction of electron-donating group on β-diketonate can enlarge their nonlinear optical properties. On the contrary, the introduction of electron-drawing group dropped it down.
文摘The effects of nitric oxide (NO) and exogenous ethylene on ethylene biosynthesis in harvested Feicheng peaches were studied. The antagonistic actions between NO and exogenous ethylene was also investigated. The Feicheng peaches were fumigated with 10μL L^-1 NO, 1 000 μL L^-1 ethylene, or 10 μL L^-1 NO plus 1 000 μL L^-1 ethylene for 3 h. The results suggested that application of exogenous ethylene promoted the biosynthesis of endogenous ethylene in peach fruit. The treatment with NO remarkably inhibited the biosynthesis of ethylene by significantly reducing the activities of ACC synthase (ACS) and ACC oxidase (ACO). Ethylene biosynthesis in the fruits treated with both NO and exogenous ethylene was lower than that in fruits treated with exogenous ethylene alone but higher than that in fruits treated with NO alone, suggesting that there were antagonistic actions between NO and exogenous ethylene. NO could inhibit the biosynthesis of ethylene and the catalysis of exogenous ethylene during ethylene biosynthesis in peach fruits.
基金Supported by Natural Science Foundation of Hunan Province(No.2016JJ4008)the Innovation Platform Open Fund Project of Hunan Provincial Education Department of China(No.16K011)+1 种基金the Open Fund Project of Key Laboratory of Functional Organometallic Materials of Hengyang Normal University(Nos.GN16k01,GN16K03)the Scientific and Technological Projects of Hengyang(No.2016KJ04)
文摘2-Oxo-butyric acid salicylacylhydrazone dibenzyltin(IV) complexes 1 {[o-OHC6H4(O)C=N-N=C(Et)COO](CH3OH)[(C6H5CH2)2Sn]}2 and 2 {[o-OH-C6H4(O)C=N-N=C(Et)-COO](CH3OH)[(2,4-Cl2C6H3CH2)2Sn]}2 have been synthesized. The complexes were characterized by IR, 1H, 13C and 119Sn NMR spectra, elemental analysis and thermal stability analysis, and the crystal structures were determined by X-ray diffraction. The crystal of complex 1 belongs to triclinic system, space group P1 with a = 8.9121(6), b = 10.3875(7), c = 14.5658(10) ?, α = 89.534(5), β = 86.790(5), γ = 70.103(6)°, Z = 1, V = 1265.85(15) ?3, Dc = 1.488 Mg·m^(-3), m(Mo Kα) = 1.047 mm-1, F(000) = 576, R = 0.0466 and w R = 0.1054. The crystal of complex 2 belongs to monoclinic system, space group P21/n, a = 12.7165(10), b = 17.8466(14), c = 12.8538(10) ?, β = 95.1310(10)°, Z = 2, V = 2905.4(4) ?~3, Dc = 1.612 Mg·m^(-3), m(Mo Kα) = 1.286 mm-1, F(000) = 1408, R = 0.0369 and w R = 0.0958. In vitro antitumor activities of both complexes were evaluated by the 3-(4,5-dimethylthiazoly-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay against three human cancer cell lines(NCI-H460, HepG2, MCF7) and one human cell line(HL7702). Two complexes exhibited strong antitumor activity, and then they were expected after further chemical optimization of candidate compounds as anti-cancer drugs. The interaction between complexes and calf thymus DNA were studied by EB fluorescent probe. The interactions of the two complexes with calf thymus DNA were intercalation.