The paper was to explore the effect of trace and secondary elements on scab of cucurbits （ Cladosporium cucumerinum） and their effects on enzyme activities of cucumber plants. [ Method ] Indoor antifungd experiment ...The paper was to explore the effect of trace and secondary elements on scab of cucurbits （ Cladosporium cucumerinum） and their effects on enzyme activities of cucumber plants. [ Method ] Indoor antifungd experiment and pot test was carried out to study the control effect of different trace and secondary dements on scab of cucu.rbits; after trace and secondary element compounds were sprayed for 7 d, the content of soluble protein and malondialdehyde （MDA） and the activities of peroxidase （POD） and superoxide dismutase （SOD） of cucumber leaves during seedling stage were simultaneously detected. [ Result] The inhibi- tion effects on scab of cucurbits were found in the three trace and secondary dements, especially for the CaC12 （66.9%）, and about 54.6% and 24.1% for ZnSO4 and H3 BO3 , respectively. When cucumber plants were infected by scab of cuea.rbits, the contents of MDA for all treatments were significantly decreased in cucum- ber leaves after spraying the three trace and secondary elements compared with control. The contents of soluble protein in cucumber seedling were increased by Zn- SO4 and H3 BO3 application, while the contents of POD and SOD were increased on ZnSO4 and CaCI2 treatments. The defense system of cucumber was induced and strengthened by application of the three trace and secondary elements. [ Conclusion ] The results provided the theoretical basis for practical application and research on resistance mechanism of using trace and secondary dements to control scab of eueurbits.展开更多
The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when th...The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when the cations are the same and the anions are different,in complex 1,Na^(+)closes one port of CyB5Q[5]through Na—O seven coordination bonds to form a molecular bowl;in complex 3,Na^(+)completely closes the two ports of CyB5Q[5]to form a molecular capsule with six Na—O coordination bonds;in complexes 2 and 4,the two ports of CyB5Q[5]are completely closed to form K—O coordinated molecular capsules,but the K^(+)of complex 2 is six-coordinated and that of complex 4 is eight-/nine-coordinated.and complex 4 are connected by three oxygen bridges to form a 1D molecular chain.CCDC:2457122,1;2457121,2;2457400,3;2457120,4.展开更多
The ongoing development of small molecule drugs underscores the urgent need for novel excipients to formulate poorly soluble drug candidates.Cucurbit[7]uril(CB[7])possesses high binding affinities for a variety of mol...The ongoing development of small molecule drugs underscores the urgent need for novel excipients to formulate poorly soluble drug candidates.Cucurbit[7]uril(CB[7])possesses high binding affinities for a variety of molecular vips.However,its moderate water solubility limits broader application.Here we report the synthesis of three CB[7]derivatives M1-M3 by modifying an average of 4.2,5.5,and 5.9 sulfonatopropoxy groups onto their"equator"carbons.Compared to CB[7],their water-solubility increased by at least 26.6-,23.6-,and 19.2-fold,respectively,while the maximum tolerated doses(MTD)of M1 and M2 improved by 2.5-and 2.3-fold.Phase solubility diagram studies demonstrate that M1 and M2 significantly enhance the water-solubility of eighteen poorly soluble drugs.In vivo experiments in rat complete Freund's arthritis reveal that M1 not only improves the anti-inflammatory efficacy of indomethacin by up to 52%,but also substantially reduces its side effect of gastric ulcer.展开更多
This investigation focuses on the utilization of cucurbit[6]uril(Q[6])as the host compound for the development of long-lasting afterglow materials.By strategically manipulating the outer surface interactions of Q[6],c...This investigation focuses on the utilization of cucurbit[6]uril(Q[6])as the host compound for the development of long-lasting afterglow materials.By strategically manipulating the outer surface interactions of Q[6],classical aggregation-caused quenching(ACQ)compounds such as fluorescein sodium(FluNa)and calcein sodium(CalNa)were transformed into afterglow materials with varying colors and durations upon exposure to ultraviolet light.This transformation was facilitated through a host-vip doping method combined with coordination with metal ions.Even at a reduced doping concentration of 5×10^(-5)wt%,the materials exhibit remarkable afterglow properties,lasting up to 2 s,with a phosphorescence lifetime of up to 150 ms.Moreover,by adjusting the concentration of the vip compound,the persistent luminescence color of the materials could be easily transitioned from orange to yellow and subsequently to green.These findings suggest that the developed afterglow materials hold significant potential for multilevel anti-counterfeiting and information encryption applications when exposed to ultraviolet light.The supramolecular assembly strategy,which relies on the outer surface interactions of cucurbit[n]uril,offers a simpler and more efficient approach to crafting multi-color luminescent materials.Additionally,this method opens avenues for enhancing the application potential of aggregation-caused quenching(ACQ)compounds in various technological domains.展开更多
Selective separation of amino acids and proteins is crucial in various areas of research,including proteomics,protein structure and function studies,protein purification and drug development,and biosensing and biodete...Selective separation of amino acids and proteins is crucial in various areas of research,including proteomics,protein structure and function studies,protein purification and drug development,and biosensing and biodetection.A nanocomposite film is formed by combining layer-by-layer self-assembled gold nanospheres(Au NPs)driven by cucurbit[7]uril(CB[7])and polymethyl methacrylate(PMMA)film.Due to the host-vip interactions,the selective transmission of l-tryptophan in the nanocomposite film is confirmed by the current-voltage measurements using a picoammeter.Furthermore,by adjusting the particle size of Au NPs to increase channel size,lysozyme containing multiple tryptophan residues can selectively pass through the nanocomposite film,indicating the high versatility and adaptability of the nanocomposite film.This study will provide a new direction for the selective separation of amino acids and proteins.展开更多
The cross-photodimerization often comes with the formation of undesired and competitive homophotodimer as side products.Herein,we report a series of highly selective[4+4]cross-photodimerization between anthracene and ...The cross-photodimerization often comes with the formation of undesired and competitive homophotodimer as side products.Herein,we report a series of highly selective[4+4]cross-photodimerization between anthracene and 4a-azoniaanthracene derivatives within a cucurbit[10]uril(CB[10])host in water.Heteroternary inclusion complexes were formed through encapsulation of donor(D1-D2,anthracene derivative)and acceptor(A1-A3,4a-azoniaanthracene derivatives)pairs in CB[10].In the presence of CB[10](1.0 equiv.),the[4+4]cross-photodimerization between D1 and A1/A2/A3 efficiently gave a single racemic cross-photodimer.Furthermore,the cross-photodimerization between 9-substituted anthracene D2 and A1/A3 was catalyzed by CB[10](0.1 equiv.)to quantitatively yield a cross-photodimer with high regioselectivity.Efficient formation of selective cross-photodimers could be attributed to the exclusive encapsulation of D-A hetero-vip pairs in CB[10]and the confinement effect of the CB[10]host cavity.Our study further proves host–vip complexation as a powerful strategy for cross-cycloaddition reactions with high efficiency.展开更多
Purely organic room-temperature phosphorescence(RTP)and fluorescence dual-emission materials in aqueous solution have attracted growing attention.Herein,we report a fluorescencephosphorescence dual emission host-vip...Purely organic room-temperature phosphorescence(RTP)and fluorescence dual-emission materials in aqueous solution have attracted growing attention.Herein,we report a fluorescencephosphorescence dual emission host-vip complex by simple assembly of cucurbit[8]uril(CB[8])and4-(4-bromophenyl)pyridinium derivative in water.Macrocyclic confinement and unique 1:2 host-vip structure could effectively inhibit non-radiative transition of the vip and the quenching of water molecule,thus induce effective RTP emission in water(τ_(RTP)=0.472 ms,Φ_(RTP)=1.37%).Specifically,based on competitive binding,this host-vip complex exhibits rapid ratiometric luminescent detection behavior to 3-nitrotyrosine,a specific biomarker of kidney injury,with a low limit of detection of 10.7 nmol/L.This work highlights the great potential of macrocyclic-confinement-derived RTP materials in biomarker detection,and will undoubtedly broaden the utilization scope of RTP.展开更多
The electrochemical conversion of CO_(2) into value‐added chemicals represents a critical strategy for sustainable energy utilization and environmental remediation.In this work,we develop a supramolecular engineering...The electrochemical conversion of CO_(2) into value‐added chemicals represents a critical strategy for sustainable energy utilization and environmental remediation.In this work,we develop a supramolecular engineering approach by constructing cucurbit[6]uril(CB[6])‐modified copper‐based electrocatalysts that create dynamic metal‐organic interfaces,which couple the captured CO_(2) with a hydrophobic surface microenvironment for efficient CO_(2) electroreduction to CO.Systematic investigations reveal that the functionalization with CB[6]simultaneously modulates the oxidation state of Cu sites,enriches local CO_(2) concentration via host‐vip interactions,and optimizes interfacial hydrophobicity.These synergistic effects lead to a significant enhancement in CO selectivity,achieving a faradaic efficiency of up to 98.3%for CO.The modified interfaces also demonstrate superior operational stability,maintaining catalytic activity for extended durations of up to 12 h.This study provides both fundamental insights into supramolecular interface engineering and a practical strategy for advancing CO_(2) conversion technologies.展开更多
Pyridine(Py) and 3-methylpyridine(3-MP) are crucial intermediates in chemical industrial processes.Here,we provide a simple and energy-efficient approach for the isolation of Py and 3-MP by employing crystalline cucur...Pyridine(Py) and 3-methylpyridine(3-MP) are crucial intermediates in chemical industrial processes.Here,we provide a simple and energy-efficient approach for the isolation of Py and 3-MP by employing crystalline cucurbit[6]uril(Q[6]).The crystal exhibit high selectivity for Py from the mixture of Py and 3-MP in both vapor and liquid phases,with separation purities close to 100%.The selectivity is attributed to the varying stability of the host-vip complexes after the absorption of Py or 3-MP,as revealed by the single-crystal structure analysis.ITC experimental results and DFT calculations indicate that,compared to3-MP,Q[6] has a higher binding strength and lower binding energy with Py.In addition,pyridine can be removed from the Q[6] cavity through vacuum heating or organic solvent immersion,enabling Q[6]reuse via reversible vip loading.This method offers a promising approach for high-purity Py and 3-MP separation with significant economic and environmental benefits.展开更多
In 2010, a foliar and stem-lesion disease that produced moderate to severe defoliation of watermelon was observed in the southern Great Plains. The disease was ultimately determined to be caused by Myrothecium roridum...In 2010, a foliar and stem-lesion disease that produced moderate to severe defoliation of watermelon was observed in the southern Great Plains. The disease was ultimately determined to be caused by Myrothecium roridum. The objective of this study was to compare the susceptibility of the vegetation and fruit of a broad range of commercially important cucurbits to three isolates obtained from these foliar lesions on watermelon. In greenhouse foliar inoculation experiments, cantaloupe, honeydew, cucumber, squash, and watermelon were susceptible to the fungus with cantaloupe and honeydew being the most susceptible and watermelon the most resistant. Furthermore, greenhouse inoculations supported earlier field observations as differential resistance was exhibited among the watermelon cultivars as well as the cucurbit types. All tested cucurbit fruit exhibited interior lesions when inoculated sub-epidermally with M. roridum isolates. However, natural infection of watermelon and pumpkin fruit has never been reported.展开更多
Phenylalanine ammonia-lyase （PAL）, the first enzyme of phenylpropanoid pathway, is always encoded by multigene families in plants. In this study, using genome-wide searches, 13 PAL genes in cucumber （CsPAL1-13） an...Phenylalanine ammonia-lyase （PAL）, the first enzyme of phenylpropanoid pathway, is always encoded by multigene families in plants. In this study, using genome-wide searches, 13 PAL genes in cucumber （CsPAL1-13） and 13 PALs in melon （Cm- PALl-13） were identified. In the corresponding genomes, ten of these PAL genes were located in tandem in two clusters, while the others were widely dispersed in different chromosomes as a single copy. The protein sequences of CsPALs and CmPALs shared an overall high identity to each other. In our previous report, 12 PAL genes were identified in watermelon （CIPAL1-12）. Thereby, a total of 38 cucurbit PAL members were included. Here, a comprehensive comparison of PAL gene families was performed among three cucurbit plants. The phylogenetic and syntenic analyses placed the cucurbit PALs as 11 CsPAL-CmPAL-CIPAL triples, of which ten triples were clustered into the dicot group, and the remaining one, CsPAL1-CmPAL8-CIPAL2, was grouped with gymnosperm PALs and might serve as an ancestor of cucurbit PALs. By comparing the syntenic relationships and gene structure of these PAL genes, the expansion of cucurbit PAL families might arise from a series of segmental and tandem duplications and intron insertion events. Furthermore, the expression profiling in different tissues suggested that different cucurbit PALs displayed divergent but overlapping expression profiles, and the CsPAL-CmPAL-CIPAL orthologs showed correlative expression patterns among three cucurbit plants. Taken together, this study provided an extensive description on the evolution and expression of cucurbit PAL gene families and might facilitate the further studies for elucidating the functions of PALs in cucurbit plants.展开更多
The insecticide cartap （CP） is non-fluorescent in aqueous solutions. This property makes its determination through direct fluorescent method difficult. In acidic medium and at room temperature, palmatine （PAL） can...The insecticide cartap （CP） is non-fluorescent in aqueous solutions. This property makes its determination through direct fluorescent method difficult. In acidic medium and at room temperature, palmatine （PAL） can react with cucurbit[7]uril （CB[7]） to form stable complexes, and the fluorescence intensity of the complex is greatly enhanced. Significant quenching of the fluorescence intensity of the CB[7]-PAL complex was observed with the addition of cartap. Based on the significant quenching of the supramolecular complex fluorescence intensity, a new spectrofluorimetric method with high sensitivity and selectivity was developed to determine cartap in aqueous solution. The fluorescence quenching values （AF） showed good linear relationship with cartap concentrations from 0.009 to 2.4 ~tg mL-~ with a detection limit 0.0029 ~tg mE-x. The proposed method had been successfully applied to the determination of cartap residues in grain and vegetable with recoveries of 87.4-103%. In addition, the association constants of the complexes formed between the host and the vip were determined. The competing reaction and the supramolecular interaction mechanisms between the cartap and PAL as they fight for occupancy of the CB[7] cavity were studied using spectrofluorimetry, xH NMR and molecular modeling calculations.展开更多
Viral diseases are among the most critical damaging factors that impose a global threat to the cucurbit industry.China is the world’s leading country for the production and consumption of cucurbits.Guangdong,a provin...Viral diseases are among the most critical damaging factors that impose a global threat to the cucurbit industry.China is the world’s leading country for the production and consumption of cucurbits.Guangdong,a province in southern China dominated by the tropical and subtropical climate,favors the survival of different plant viruses and their vectors.Five main cucurbit crops showing various disease symptoms were surveyed and collected to identify viruses infecting cucurbits in Guangdong during 2018–2020.In the field,the incidence ranged from 5-30%,or even 60-100% in the case of severely infected cucurbits.A total of 357 symptomatic samples were collected and subsequently screened for cucurbit viruses by small RNA deep sequencing and assembly(sRSA).Seventeen virus species belonging to 10 genera were identified in the five main cucurbit crops.The most common viruses were papaya ringspot virus(PRSV;Potyvirus),zucchini tigre mosaic virus(ZTMV;Potyvirus),zucchini yellow mosaic virus(ZYMV;Potyvirus),and watermelon silver mottle virus(WSMoV;Orthotospovirus),with infection rates of 24.4,19.0,17.1,and 14.3%,respectively.Notably,the most prevalent viruses were melon yellow spot orthotospovirus(MYSV)in cucumber,PRSV in squash,cucumber green mottle mosaic virus(CGMMV;Tobamovirus)in bottle gourd,WSMoV in white gourd,and ZYMV in luffa.Mixed infections were prevalent,and the types of mixed infections varied substantially in different cucurbit crops.Moreover,the full-length nucleotide sequences of watermelon green mottle mosaic virus(WGMMV),CGMMV,and watermelon virus A(WVA;Wamavirus)identified in bottle gourd were cloned and analyzed.This study is the first reporting WGMMV infecting bottle gourd in China mainland.In summary,the results demonstrate that in Guangdong,the most prevalent viruses belong to potyviruses,orthotospoviruses,and tobamoviruses groups.The findings will facilitate agricultural researchers and farmers to plan and implement effective disease control strategies aiming at timely detection and management of cucurbit-infecting viral pathogens.展开更多
Paraquat （PQ）, a nonselective herbicide, is non-fluorescent in aqueous solutions. Thus, its determination through direct fluorescent methods is not feasible. The supramolecular inclusion interaction of PQ with cucur...Paraquat （PQ）, a nonselective herbicide, is non-fluorescent in aqueous solutions. Thus, its determination through direct fluorescent methods is not feasible. The supramolecular inclusion interaction of PQ with cucurbit[7]uril was studied by a fluorescent probe titration method. Significant quenching of the fluorescence intensity of the cucurbit[7]uril-coptisine fluorescent probe was observed with the addition of PQ. A new fluorescent probe titration method with high selectivity and sensitivity at the ng/mL level was developed to determine PQ in aqueous solutions with good precision and accuracy based on the significant quenching of the supramolecular complex fluorescence intensity. The proposed method was successfully used in the determination of PQ in lake water, tap water, well water, and ditch water in an agricultural area, with recoveries of 96.73% to 105.77%. The fluorescence quenching values （AF） showed a good linear relationship with PQ concentrations from 1.0 × 10^-8 to 1.2× 10^-5 mol/L with a detection limit of 3.35 x 10-9 mol/L. In addition, the interaction models of the supramolecular complexes formed between the host and the vip were established using theoretical calculations. The interaction mechanism between the cucurbit[7]uril and PQ was confirmed by 1H NMR spectroscopy.展开更多
The determination method of L-phenylalartine （LPA） by fluorescence quenching was developed. The assay was based on the combination of the cucurbit[7]uril （CB [7]） with palmatine hydrochloride （PAL） reaction. In ...The determination method of L-phenylalartine （LPA） by fluorescence quenching was developed. The assay was based on the combination of the cucurbit[7]uril （CB [7]） with palmatine hydrochloride （PAL） reaction. In the presence of CB [7], the fluorescence of PAL was quenched by LPA which can be employed to detect LPA. Under the optimal conditions, a linear range 3.63 ×10^-8- 9.68 ×10^-6 mol/L and a detection limit 1.27 ×10^-8 mol/L of LPA were obtained. The relative standard deviation （R.S.D） was 1.8% obtained from a series of 11 standards each containing 6.05 ×10^-6 mol/L of LPA. This paper also discusses the mechanism of fluorescence indicator probe.展开更多
The inclusion interaction between berberine hydrochloride （BRH） and cucurbit[7] （CB[7]） has been studied by spectrofluorimetry. The result showed that CB[7] interaction with BRH to form a stable inclusion complex ...The inclusion interaction between berberine hydrochloride （BRH） and cucurbit[7] （CB[7]） has been studied by spectrofluorimetry. The result showed that CB[7] interaction with BRH to form a stable inclusion complex with an association constant of 9.57 × 10^4 L/mol and the fluorescence intensity of the complex was enhanced in 17 times higher than that of the studied drug itself. Based on the significant enhancement of fluorescence intensity of BRH in inclusion complex, a spetrofluorimetric method with high sensitivity and selectivity was developed for the determination of BRH in aqueous solution. The linear range of the method was 3.2- 2 × 10^3 ng/mL with a detection limit of 1.1 ng/mL. The proposed procedure could be applied successfully to determination of BRH remained in pharmaceutical dosage forms, spiked human plasma and urine with satisfactory results.展开更多
DNA barcoding is a supplementary tool in plant systematics,extensively used to resolve the species level controversies.This paper details the identification of DNA barcodes for seven species of Momordica,using the chl...DNA barcoding is a supplementary tool in plant systematics,extensively used to resolve the species level controversies.This paper details the identification of DNA barcodes for seven species of Momordica,using the chloroplast gene mat K.Since the species M.cymbalaria has been confused as a member of the genus Luffa,26 accessions of Momordica belonging to seven Indian species and two accessions of Luffa acutangula were included in this study.Analysis of mat K sequences has yielded distinct barcodes in M.charantia var.charantia,M.subangulata subsp.renigera,M.cochinchinensis,M.balsamina,M.cymbalaria and also in Luffa acutangula.Evolutionary status of each species was reflected as nucleotide polymorphisms in each sequence.The wild species M.dioica and M.sahyadrica have yielded one barcode but failed to get differentiated.Further,this study provides conclusive proof that M.cymbalaria is a member of Momordica genus.The phylogram generated was successful to distinguish the monoecious species of this genus,M.charantia,M.balsamina and M.cymbalaria,from the dioecious species M.dioica,M.sahyadrica,M.subangulata subsp.renigera and M.cochinchinensis.Thus,mat K locus,by accumulating the evolutionary sequence variations,is proven efficient to differentiate the Momordica species and to reveal their relatedness.展开更多
A supramolecular dimer of doxorubicin(DOX)was constructed via ternary host-vip interactions between cucurbit[8]uril(CB[8])and tryptophan modified DOX(DOX-Trp,connected with an acid-labile bond)and we demonstrate for...A supramolecular dimer of doxorubicin(DOX)was constructed via ternary host-vip interactions between cucurbit[8]uril(CB[8])and tryptophan modified DOX(DOX-Trp,connected with an acid-labile bond)and we demonstrate for the first time that a supramolecular dimer of DOX can be formed upon homo-dimerization by CB[8],which may act as a stimuli pH-responsive,supramolecular DOX dimer prodrug system.This supramolecular DOX dimer transported DOX efficiently and selectively to cancer cells,thereby exhibiting significantly minimized cytotoxicity against noncancerous cells while maintaining effective cytotoxicity against cancer cells.Under this strategy,many other anticancer drugs could be chemically modified and loaded as a dimeric"ammunition"into CB[8]as supramolecular dimer prodrug systems(or a"jet fighter")for improved cancer therapy.展开更多
In this paper,the host-vip interaction of cucurbit[7]uril(Q[7]) and chromone(CMO) has been developed as a fluorescent probe for the highly selective detection of Zn2+ and Cd^(2+) in water based on a chelation-enhanc...In this paper,the host-vip interaction of cucurbit[7]uril(Q[7]) and chromone(CMO) has been developed as a fluorescent probe for the highly selective detection of Zn2+ and Cd^(2+) in water based on a chelation-enhanced fluorescence(CHEF) mechanism.There was a good linear relationship between the fluorescence intensity of the CMO@Q[7] probe and the concentration of Zn^(2+ )or Cd^(2+) in the range of 0-3.0×10^(-5) mol/L and the detection limit for Zn^(2+) and Cd2+ was found to be 2.03×10^(-6) mol/L and 1.89×10^(-6)mol/L,respectively.The X-ray crystal structure indicated that different coordination fashions were triggered by Zn^(2+) and Cd^(2+ )in the CMO@Q[7] complexes,respectively.However,both metal ions coordinated with the carbonyl oxygen of CMO,which was encapsulated in the cavity of Q[7],thus leading to the enhancement of recognition fluorescence emission of CMO.展开更多
Cucurbit[n]urils （CB[n]s, n = 5-8,10,13-15） have been proven to be an interesting macrocyclic family with their distinctive molecular recognition properties and fascinating applications in fields such as catalysis, ...Cucurbit[n]urils （CB[n]s, n = 5-8,10,13-15） have been proven to be an interesting macrocyclic family with their distinctive molecular recognition properties and fascinating applications in fields such as catalysis, supramolecular materials, drug delivery and biological systems. With the biggest cavity in the CB[n]s family. CB[ 10] shows its unique molecular recognition properties that are rather distinctive from other CB [n]is. In this review, we summarize the progresses in CB[10]-based chemistry since CB[10] was first reported as CB[10]-CB[5] complex in 2001. Purification, molecular recognition and supramolecular assembly of CB[ 10] will be described and an outlook will be given for further exploration of CB[10]-based chemistry.展开更多
基金Supported by Liaoning Natural Science Foundation Project(20062124)~~
文摘The paper was to explore the effect of trace and secondary elements on scab of cucurbits （ Cladosporium cucumerinum） and their effects on enzyme activities of cucumber plants. [ Method ] Indoor antifungd experiment and pot test was carried out to study the control effect of different trace and secondary dements on scab of cucu.rbits; after trace and secondary element compounds were sprayed for 7 d, the content of soluble protein and malondialdehyde （MDA） and the activities of peroxidase （POD） and superoxide dismutase （SOD） of cucumber leaves during seedling stage were simultaneously detected. [ Result] The inhibi- tion effects on scab of cucurbits were found in the three trace and secondary dements, especially for the CaC12 （66.9%）, and about 54.6% and 24.1% for ZnSO4 and H3 BO3 , respectively. When cucumber plants were infected by scab of cuea.rbits, the contents of MDA for all treatments were significantly decreased in cucum- ber leaves after spraying the three trace and secondary elements compared with control. The contents of soluble protein in cucumber seedling were increased by Zn- SO4 and H3 BO3 application, while the contents of POD and SOD were increased on ZnSO4 and CaCI2 treatments. The defense system of cucumber was induced and strengthened by application of the three trace and secondary elements. [ Conclusion ] The results provided the theoretical basis for practical application and research on resistance mechanism of using trace and secondary dements to control scab of eueurbits.
文摘The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when the cations are the same and the anions are different,in complex 1,Na^(+)closes one port of CyB5Q[5]through Na—O seven coordination bonds to form a molecular bowl;in complex 3,Na^(+)completely closes the two ports of CyB5Q[5]to form a molecular capsule with six Na—O coordination bonds;in complexes 2 and 4,the two ports of CyB5Q[5]are completely closed to form K—O coordinated molecular capsules,but the K^(+)of complex 2 is six-coordinated and that of complex 4 is eight-/nine-coordinated.and complex 4 are connected by three oxygen bridges to form a 1D molecular chain.CCDC:2457122,1;2457121,2;2457400,3;2457120,4.
基金National Natural Science Foundation of China(Nos.21921003 and 22201293)the National Key R&D Program of China(No.2023YFC3503400)for financial support。
文摘The ongoing development of small molecule drugs underscores the urgent need for novel excipients to formulate poorly soluble drug candidates.Cucurbit[7]uril(CB[7])possesses high binding affinities for a variety of molecular vips.However,its moderate water solubility limits broader application.Here we report the synthesis of three CB[7]derivatives M1-M3 by modifying an average of 4.2,5.5,and 5.9 sulfonatopropoxy groups onto their"equator"carbons.Compared to CB[7],their water-solubility increased by at least 26.6-,23.6-,and 19.2-fold,respectively,while the maximum tolerated doses(MTD)of M1 and M2 improved by 2.5-and 2.3-fold.Phase solubility diagram studies demonstrate that M1 and M2 significantly enhance the water-solubility of eighteen poorly soluble drugs.In vivo experiments in rat complete Freund's arthritis reveal that M1 not only improves the anti-inflammatory efficacy of indomethacin by up to 52%,but also substantially reduces its side effect of gastric ulcer.
基金support of the National Natural Science Foundation of China(No.22361011)Guizhou Provincial Science and Technology Projects(No.ZK[2023]General 040)the Guizhou Provincial Key Laboratory Platform Project(No.ZSYS[2025]008)。
文摘This investigation focuses on the utilization of cucurbit[6]uril(Q[6])as the host compound for the development of long-lasting afterglow materials.By strategically manipulating the outer surface interactions of Q[6],classical aggregation-caused quenching(ACQ)compounds such as fluorescein sodium(FluNa)and calcein sodium(CalNa)were transformed into afterglow materials with varying colors and durations upon exposure to ultraviolet light.This transformation was facilitated through a host-vip doping method combined with coordination with metal ions.Even at a reduced doping concentration of 5×10^(-5)wt%,the materials exhibit remarkable afterglow properties,lasting up to 2 s,with a phosphorescence lifetime of up to 150 ms.Moreover,by adjusting the concentration of the vip compound,the persistent luminescence color of the materials could be easily transitioned from orange to yellow and subsequently to green.These findings suggest that the developed afterglow materials hold significant potential for multilevel anti-counterfeiting and information encryption applications when exposed to ultraviolet light.The supramolecular assembly strategy,which relies on the outer surface interactions of cucurbit[n]uril,offers a simpler and more efficient approach to crafting multi-color luminescent materials.Additionally,this method opens avenues for enhancing the application potential of aggregation-caused quenching(ACQ)compounds in various technological domains.
基金financially supported by National Natural Science Foundation of China(Nos.22371086,22071074,21772055)the National Key Research and Development Program(No.2021YFA0716702)+3 种基金the 111 Project(No.B17019)the China Postdoctoral Science Foundation(No.2020 M672388)Self-determined research funds of CCNU from the colleges’basic research and operation of MOE,National Natural Science Foundation of China(No.22006055)the State Key Laboratory of Environmental Chemistry and Ecotoxicology,RCEES,CAS(No.KF2017-4)。
文摘Selective separation of amino acids and proteins is crucial in various areas of research,including proteomics,protein structure and function studies,protein purification and drug development,and biosensing and biodetection.A nanocomposite film is formed by combining layer-by-layer self-assembled gold nanospheres(Au NPs)driven by cucurbit[7]uril(CB[7])and polymethyl methacrylate(PMMA)film.Due to the host-vip interactions,the selective transmission of l-tryptophan in the nanocomposite film is confirmed by the current-voltage measurements using a picoammeter.Furthermore,by adjusting the particle size of Au NPs to increase channel size,lysozyme containing multiple tryptophan residues can selectively pass through the nanocomposite film,indicating the high versatility and adaptability of the nanocomposite film.This study will provide a new direction for the selective separation of amino acids and proteins.
基金financially supported by the National Natural Science Foundation of China(No.21871216)。
文摘The cross-photodimerization often comes with the formation of undesired and competitive homophotodimer as side products.Herein,we report a series of highly selective[4+4]cross-photodimerization between anthracene and 4a-azoniaanthracene derivatives within a cucurbit[10]uril(CB[10])host in water.Heteroternary inclusion complexes were formed through encapsulation of donor(D1-D2,anthracene derivative)and acceptor(A1-A3,4a-azoniaanthracene derivatives)pairs in CB[10].In the presence of CB[10](1.0 equiv.),the[4+4]cross-photodimerization between D1 and A1/A2/A3 efficiently gave a single racemic cross-photodimer.Furthermore,the cross-photodimerization between 9-substituted anthracene D2 and A1/A3 was catalyzed by CB[10](0.1 equiv.)to quantitatively yield a cross-photodimer with high regioselectivity.Efficient formation of selective cross-photodimers could be attributed to the exclusive encapsulation of D-A hetero-vip pairs in CB[10]and the confinement effect of the CB[10]host cavity.Our study further proves host–vip complexation as a powerful strategy for cross-cycloaddition reactions with high efficiency.
基金financially supported by the National Natural Science Foundation of China(Nos.22171069 and 21871075)the Educational Committee of Hebei Province(No.JZX2024012)the Tianjin Natural Science Foundation(No.23JCYBJC00800)。
文摘Purely organic room-temperature phosphorescence(RTP)and fluorescence dual-emission materials in aqueous solution have attracted growing attention.Herein,we report a fluorescencephosphorescence dual emission host-vip complex by simple assembly of cucurbit[8]uril(CB[8])and4-(4-bromophenyl)pyridinium derivative in water.Macrocyclic confinement and unique 1:2 host-vip structure could effectively inhibit non-radiative transition of the vip and the quenching of water molecule,thus induce effective RTP emission in water(τ_(RTP)=0.472 ms,Φ_(RTP)=1.37%).Specifically,based on competitive binding,this host-vip complex exhibits rapid ratiometric luminescent detection behavior to 3-nitrotyrosine,a specific biomarker of kidney injury,with a low limit of detection of 10.7 nmol/L.This work highlights the great potential of macrocyclic-confinement-derived RTP materials in biomarker detection,and will undoubtedly broaden the utilization scope of RTP.
基金L.P.acknowledges funding support from the National Natural Science Foundation of China(Grant 22373080)Fujian Provincial Natural Science Foundation of China(Grant 2024J08008)+2 种基金J.L.acknowledges funding support from the National Natural Science Foundation of China(Grant 22078274)S.Y.acknowledges funding support from the Fundamental Research Funds for the Central Universities(Grant 20720240054)the Nan‐qiang Youth Scholar Program of Xiamen University and Xiaomi Young Talents Program/Xiaomi Foundation.
文摘The electrochemical conversion of CO_(2) into value‐added chemicals represents a critical strategy for sustainable energy utilization and environmental remediation.In this work,we develop a supramolecular engineering approach by constructing cucurbit[6]uril(CB[6])‐modified copper‐based electrocatalysts that create dynamic metal‐organic interfaces,which couple the captured CO_(2) with a hydrophobic surface microenvironment for efficient CO_(2) electroreduction to CO.Systematic investigations reveal that the functionalization with CB[6]simultaneously modulates the oxidation state of Cu sites,enriches local CO_(2) concentration via host‐vip interactions,and optimizes interfacial hydrophobicity.These synergistic effects lead to a significant enhancement in CO selectivity,achieving a faradaic efficiency of up to 98.3%for CO.The modified interfaces also demonstrate superior operational stability,maintaining catalytic activity for extended durations of up to 12 h.This study provides both fundamental insights into supramolecular interface engineering and a practical strategy for advancing CO_(2) conversion technologies.
基金supported by the Guizhou Provincial Basic Research Program(Natural Science) Youth Guidance(Nos.[2024]110,[2024]378)Science and Technology Innovation Team of Natural Science Foundation of Guizhou Province(No.CXTD[2023]005)+3 种基金Science and Technology Innovation Team of Higher Education Department of Guizhou Province(No.QJJ[2023]053)Natural Science Special of Guizhou University(No.202137)Guizhou Provincial Key Laboratory Platform Project(No.ZSYS[2025]008)PhD Foundation of Guizhou University(No.[2021]83)。
文摘Pyridine(Py) and 3-methylpyridine(3-MP) are crucial intermediates in chemical industrial processes.Here,we provide a simple and energy-efficient approach for the isolation of Py and 3-MP by employing crystalline cucurbit[6]uril(Q[6]).The crystal exhibit high selectivity for Py from the mixture of Py and 3-MP in both vapor and liquid phases,with separation purities close to 100%.The selectivity is attributed to the varying stability of the host-vip complexes after the absorption of Py or 3-MP,as revealed by the single-crystal structure analysis.ITC experimental results and DFT calculations indicate that,compared to3-MP,Q[6] has a higher binding strength and lower binding energy with Py.In addition,pyridine can be removed from the Q[6] cavity through vacuum heating or organic solvent immersion,enabling Q[6]reuse via reversible vip loading.This method offers a promising approach for high-purity Py and 3-MP separation with significant economic and environmental benefits.
文摘In 2010, a foliar and stem-lesion disease that produced moderate to severe defoliation of watermelon was observed in the southern Great Plains. The disease was ultimately determined to be caused by Myrothecium roridum. The objective of this study was to compare the susceptibility of the vegetation and fruit of a broad range of commercially important cucurbits to three isolates obtained from these foliar lesions on watermelon. In greenhouse foliar inoculation experiments, cantaloupe, honeydew, cucumber, squash, and watermelon were susceptible to the fungus with cantaloupe and honeydew being the most susceptible and watermelon the most resistant. Furthermore, greenhouse inoculations supported earlier field observations as differential resistance was exhibited among the watermelon cultivars as well as the cucurbit types. All tested cucurbit fruit exhibited interior lesions when inoculated sub-epidermally with M. roridum isolates. However, natural infection of watermelon and pumpkin fruit has never been reported.
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China (31101548)the Special Fund for Agro-Scientific Research in the Public Interest, China (201303014)+1 种基金funded by the China Agriculture Research System (CARS-25)the Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences (CAAS-ASTIP-IVFCAAS)
文摘Phenylalanine ammonia-lyase （PAL）, the first enzyme of phenylpropanoid pathway, is always encoded by multigene families in plants. In this study, using genome-wide searches, 13 PAL genes in cucumber （CsPAL1-13） and 13 PALs in melon （Cm- PALl-13） were identified. In the corresponding genomes, ten of these PAL genes were located in tandem in two clusters, while the others were widely dispersed in different chromosomes as a single copy. The protein sequences of CsPALs and CmPALs shared an overall high identity to each other. In our previous report, 12 PAL genes were identified in watermelon （CIPAL1-12）. Thereby, a total of 38 cucurbit PAL members were included. Here, a comprehensive comparison of PAL gene families was performed among three cucurbit plants. The phylogenetic and syntenic analyses placed the cucurbit PALs as 11 CsPAL-CmPAL-CIPAL triples, of which ten triples were clustered into the dicot group, and the remaining one, CsPAL1-CmPAL8-CIPAL2, was grouped with gymnosperm PALs and might serve as an ancestor of cucurbit PALs. By comparing the syntenic relationships and gene structure of these PAL genes, the expansion of cucurbit PAL families might arise from a series of segmental and tandem duplications and intron insertion events. Furthermore, the expression profiling in different tissues suggested that different cucurbit PALs displayed divergent but overlapping expression profiles, and the CsPAL-CmPAL-CIPAL orthologs showed correlative expression patterns among three cucurbit plants. Taken together, this study provided an extensive description on the evolution and expression of cucurbit PAL gene families and might facilitate the further studies for elucidating the functions of PALs in cucurbit plants.
基金supported by the Research Fund for the Doctoral Program of Higher Education of China(20091404110001)
文摘The insecticide cartap （CP） is non-fluorescent in aqueous solutions. This property makes its determination through direct fluorescent method difficult. In acidic medium and at room temperature, palmatine （PAL） can react with cucurbit[7]uril （CB[7]） to form stable complexes, and the fluorescence intensity of the complex is greatly enhanced. Significant quenching of the fluorescence intensity of the CB[7]-PAL complex was observed with the addition of cartap. Based on the significant quenching of the supramolecular complex fluorescence intensity, a new spectrofluorimetric method with high sensitivity and selectivity was developed to determine cartap in aqueous solution. The fluorescence quenching values （AF） showed good linear relationship with cartap concentrations from 0.009 to 2.4 ~tg mL-~ with a detection limit 0.0029 ~tg mE-x. The proposed method had been successfully applied to the determination of cartap residues in grain and vegetable with recoveries of 87.4-103%. In addition, the association constants of the complexes formed between the host and the vip were determined. The competing reaction and the supramolecular interaction mechanisms between the cartap and PAL as they fight for occupancy of the CB[7] cavity were studied using spectrofluorimetry, xH NMR and molecular modeling calculations.
基金supported by the grants from the National Natural Science Foundation of China(31801712)the Key Research and Development Program of Guangdong Province,China(2018B020202006)+1 种基金the Agricultural Competitive Industry Discipline Team Building Project of Guangdong Academy of Agricultural Sciences(202103TD and 202105TD)the Development Program for Guangdong Province Modern Agricultural Science and Technology Innovation Alliance(2020KJ113)。
文摘Viral diseases are among the most critical damaging factors that impose a global threat to the cucurbit industry.China is the world’s leading country for the production and consumption of cucurbits.Guangdong,a province in southern China dominated by the tropical and subtropical climate,favors the survival of different plant viruses and their vectors.Five main cucurbit crops showing various disease symptoms were surveyed and collected to identify viruses infecting cucurbits in Guangdong during 2018–2020.In the field,the incidence ranged from 5-30%,or even 60-100% in the case of severely infected cucurbits.A total of 357 symptomatic samples were collected and subsequently screened for cucurbit viruses by small RNA deep sequencing and assembly(sRSA).Seventeen virus species belonging to 10 genera were identified in the five main cucurbit crops.The most common viruses were papaya ringspot virus(PRSV;Potyvirus),zucchini tigre mosaic virus(ZTMV;Potyvirus),zucchini yellow mosaic virus(ZYMV;Potyvirus),and watermelon silver mottle virus(WSMoV;Orthotospovirus),with infection rates of 24.4,19.0,17.1,and 14.3%,respectively.Notably,the most prevalent viruses were melon yellow spot orthotospovirus(MYSV)in cucumber,PRSV in squash,cucumber green mottle mosaic virus(CGMMV;Tobamovirus)in bottle gourd,WSMoV in white gourd,and ZYMV in luffa.Mixed infections were prevalent,and the types of mixed infections varied substantially in different cucurbit crops.Moreover,the full-length nucleotide sequences of watermelon green mottle mosaic virus(WGMMV),CGMMV,and watermelon virus A(WVA;Wamavirus)identified in bottle gourd were cloned and analyzed.This study is the first reporting WGMMV infecting bottle gourd in China mainland.In summary,the results demonstrate that in Guangdong,the most prevalent viruses belong to potyviruses,orthotospoviruses,and tobamoviruses groups.The findings will facilitate agricultural researchers and farmers to plan and implement effective disease control strategies aiming at timely detection and management of cucurbit-infecting viral pathogens.
基金supported by the National Natural ScienceFoundation of China (No. 21171110)the Research Fund for the Doctoral Program of Higher Education of China (No. 20091404110001)
文摘Paraquat （PQ）, a nonselective herbicide, is non-fluorescent in aqueous solutions. Thus, its determination through direct fluorescent methods is not feasible. The supramolecular inclusion interaction of PQ with cucurbit[7]uril was studied by a fluorescent probe titration method. Significant quenching of the fluorescence intensity of the cucurbit[7]uril-coptisine fluorescent probe was observed with the addition of PQ. A new fluorescent probe titration method with high selectivity and sensitivity at the ng/mL level was developed to determine PQ in aqueous solutions with good precision and accuracy based on the significant quenching of the supramolecular complex fluorescence intensity. The proposed method was successfully used in the determination of PQ in lake water, tap water, well water, and ditch water in an agricultural area, with recoveries of 96.73% to 105.77%. The fluorescence quenching values （AF） showed a good linear relationship with PQ concentrations from 1.0 × 10^-8 to 1.2× 10^-5 mol/L with a detection limit of 3.35 x 10-9 mol/L. In addition, the interaction models of the supramolecular complexes formed between the host and the vip were established using theoretical calculations. The interaction mechanism between the cucurbit[7]uril and PQ was confirmed by 1H NMR spectroscopy.
基金supported by the Research Fund for the Doctoral Program of Higher Education of China(No. 20091404110001)the foundation of Shanxi Normal University(No.ZR1007)
文摘The determination method of L-phenylalartine （LPA） by fluorescence quenching was developed. The assay was based on the combination of the cucurbit[7]uril （CB [7]） with palmatine hydrochloride （PAL） reaction. In the presence of CB [7], the fluorescence of PAL was quenched by LPA which can be employed to detect LPA. Under the optimal conditions, a linear range 3.63 ×10^-8- 9.68 ×10^-6 mol/L and a detection limit 1.27 ×10^-8 mol/L of LPA were obtained. The relative standard deviation （R.S.D） was 1.8% obtained from a series of 11 standards each containing 6.05 ×10^-6 mol/L of LPA. This paper also discusses the mechanism of fluorescence indicator probe.
基金supported by the Natural Science Foundation of Shanxi(No.2007011027).
文摘The inclusion interaction between berberine hydrochloride （BRH） and cucurbit[7] （CB[7]） has been studied by spectrofluorimetry. The result showed that CB[7] interaction with BRH to form a stable inclusion complex with an association constant of 9.57 × 10^4 L/mol and the fluorescence intensity of the complex was enhanced in 17 times higher than that of the studied drug itself. Based on the significant enhancement of fluorescence intensity of BRH in inclusion complex, a spetrofluorimetric method with high sensitivity and selectivity was developed for the determination of BRH in aqueous solution. The linear range of the method was 3.2- 2 × 10^3 ng/mL with a detection limit of 1.1 ng/mL. The proposed procedure could be applied successfully to determination of BRH remained in pharmaceutical dosage forms, spiked human plasma and urine with satisfactory results.
基金Department of Biotechnology(DBT),Govt.of India,for the fellowship and financial assistancefor his M.Sc.(Ag.)in Plant Biotechnolo gy research work(Grant No.CPBMB/CoH/DBT-HRD/12)。
文摘DNA barcoding is a supplementary tool in plant systematics,extensively used to resolve the species level controversies.This paper details the identification of DNA barcodes for seven species of Momordica,using the chloroplast gene mat K.Since the species M.cymbalaria has been confused as a member of the genus Luffa,26 accessions of Momordica belonging to seven Indian species and two accessions of Luffa acutangula were included in this study.Analysis of mat K sequences has yielded distinct barcodes in M.charantia var.charantia,M.subangulata subsp.renigera,M.cochinchinensis,M.balsamina,M.cymbalaria and also in Luffa acutangula.Evolutionary status of each species was reflected as nucleotide polymorphisms in each sequence.The wild species M.dioica and M.sahyadrica have yielded one barcode but failed to get differentiated.Further,this study provides conclusive proof that M.cymbalaria is a member of Momordica genus.The phylogram generated was successful to distinguish the monoecious species of this genus,M.charantia,M.balsamina and M.cymbalaria,from the dioecious species M.dioica,M.sahyadrica,M.subangulata subsp.renigera and M.cochinchinensis.Thus,mat K locus,by accumulating the evolutionary sequence variations,is proven efficient to differentiate the Momordica species and to reveal their relatedness.
基金supported by the Science and Technology Development Fund,Macao SAR(No.030/2017/A1)University of Macao(No.MYRG2016-00008-ICMS-QRCM)the National Natural Science Foundation of China(No.21871301)。
文摘A supramolecular dimer of doxorubicin(DOX)was constructed via ternary host-vip interactions between cucurbit[8]uril(CB[8])and tryptophan modified DOX(DOX-Trp,connected with an acid-labile bond)and we demonstrate for the first time that a supramolecular dimer of DOX can be formed upon homo-dimerization by CB[8],which may act as a stimuli pH-responsive,supramolecular DOX dimer prodrug system.This supramolecular DOX dimer transported DOX efficiently and selectively to cancer cells,thereby exhibiting significantly minimized cytotoxicity against noncancerous cells while maintaining effective cytotoxicity against cancer cells.Under this strategy,many other anticancer drugs could be chemically modified and loaded as a dimeric"ammunition"into CB[8]as supramolecular dimer prodrug systems(or a"jet fighter")for improved cancer therapy.
基金support from the Science and Technology Support Plan of Guizhou Province [Guizhou Science and Technology Cooperation Support (2020) 4Y218]。
文摘In this paper,the host-vip interaction of cucurbit[7]uril(Q[7]) and chromone(CMO) has been developed as a fluorescent probe for the highly selective detection of Zn2+ and Cd^(2+) in water based on a chelation-enhanced fluorescence(CHEF) mechanism.There was a good linear relationship between the fluorescence intensity of the CMO@Q[7] probe and the concentration of Zn^(2+ )or Cd^(2+) in the range of 0-3.0×10^(-5) mol/L and the detection limit for Zn^(2+) and Cd2+ was found to be 2.03×10^(-6) mol/L and 1.89×10^(-6)mol/L,respectively.The X-ray crystal structure indicated that different coordination fashions were triggered by Zn^(2+) and Cd^(2+ )in the CMO@Q[7] complexes,respectively.However,both metal ions coordinated with the carbonyl oxygen of CMO,which was encapsulated in the cavity of Q[7],thus leading to the enhancement of recognition fluorescence emission of CMO.
基金financially supported by the National Natural Science Foundation of China (Nos. 21472143, 21604066 and 21372183)Thousand Youth Talents Program of China (No. D1118031)Program for Innovative Teams of Outstanding Young and Middle-aged Researchers in the Higher Education Institutions of Hubei Province (No. T201602)
文摘Cucurbit[n]urils （CB[n]s, n = 5-8,10,13-15） have been proven to be an interesting macrocyclic family with their distinctive molecular recognition properties and fascinating applications in fields such as catalysis, supramolecular materials, drug delivery and biological systems. With the biggest cavity in the CB[n]s family. CB[ 10] shows its unique molecular recognition properties that are rather distinctive from other CB [n]is. In this review, we summarize the progresses in CB[10]-based chemistry since CB[10] was first reported as CB[10]-CB[5] complex in 2001. Purification, molecular recognition and supramolecular assembly of CB[ 10] will be described and an outlook will be given for further exploration of CB[10]-based chemistry.
