Microarc oxidation is an effective surface treatment for improving certain properties of metals and their alloys.In this paper,TiO_(2)/Cu_(2)O and TiO_(2)/Cu_(2)O@CeO_(2)coatings were prepared on Ti-6Al-4V by microarc...Microarc oxidation is an effective surface treatment for improving certain properties of metals and their alloys.In this paper,TiO_(2)/Cu_(2)O and TiO_(2)/Cu_(2)O@CeO_(2)coatings were prepared on Ti-6Al-4V by microarc oxidation.Thecoatings exhibited good corrosion resistance and antimicrobial properties.X-ray diffraction(XRD),scanning electronmicroscopy(SEM),and 3D laser confocal were used to characterize the coatings.The properties of TiO_(2)/Cu_(2)O and TiO_(2)/Cu_(2)O@CeO_(2)coatings were analyzed,including microstructure,surface roughness,corrosion resistance,andantimicrobial properties.The electrochemical results showed that the coatings prepared by microarc oxidation hadenhanced corrosion resistance compared to the substrate.The antibacterial properties of TiO_(2)/Cu_(2)O and TiO_(2)/Cu_(2)O@CeO_(2)coating against Pseudomonas aeruginosa were evaluated by fluorescence microscopy and plate counting.The antibacterial rate of TiO_(2)/Cu_(2)O@CeO_(2)coating was up to 99.70%.In summary,the TiO_(2)/Cu_(2)O and TiO_(2)/Cu_(2)O@CeO_(2)coatings prepared by microarc oxidation have a potential application background in the field of marine corrosionprotection and biofouling.展开更多
The structure, properties and application to water-soluble coatings of a new complex antimicrobial agent Ag-carboxylmethyl citosan-thiabendazole （Ag-CMCTS-TBZ） prepared from different materiel ratios were reported. ...The structure, properties and application to water-soluble coatings of a new complex antimicrobial agent Ag-carboxylmethyl citosan-thiabendazole （Ag-CMCTS-TBZ） prepared from different materiel ratios were reported. The silver ions were preferably coordinated with the free-NH2 groups and the -OH groups of secondary alcohol and carboxyl in CMCTS. TBZ preferably bonded to carboxyl group in CMCTS by electrostatic force and hydrogen bonding. Increase in silver ions content in the complex agent improved to some limited extent the antibacterial activity, but enhanced coloring and cost of the complex agent. Increase in TBZ content resulted in increase of antifungal activity, but decrease of water solubility of the complex agent. The antimicrobial MICs of the complex agent to Esherichia coil, Staphylococcus aureus, Candida albicans, Aspergillus niger, Mucor sp. were 20 -80, 15 -60, 20 - 55, 40 - 250, and 400 - 1700 mg/kg, respectively. Addition of 0.1% of this complex agent to acrylic emulsion paint made the paint without substantial change in color, luster, viscosity, odor or pH value, but with an excellent and chronically persisting broad-spectra antimicrobial activity.展开更多
The liquid ion exchange method, solid salt melt method and dry-wet circulation method were used to prepare natural porous antimicrobial materials with natural minerals, such as zeolite, spilite, palygorskite and montm...The liquid ion exchange method, solid salt melt method and dry-wet circulation method were used to prepare natural porous antimicrobial materials with natural minerals, such as zeolite, spilite, palygorskite and montmorillonite, respectively. Atomic absorption spectrum and X-ray diffraction analysis were carried out to investigate the effects of Ag^＋ , Cu^2＋ and Zn^2＋ on antimicrobial abilities of natural porous minerals, and the effect of preparation method on ion exchange capacity of antimicrobial material, respectively. The results show that for the ion exchange capacity, clay mineral is higher than fibrous mineral, i.e. both zeolite and montmorillonite are higher; the antimicrobial ability of material with Ag^＋ is the bests the exchange capacities of materials with Cu^2＋ or Zn^2＋ are all higher, but the antimicrobial ability of Cu^2＋ is better than that of Zn^2＋ .展开更多
Antimicrobial peptides are widely distributed in nature,existing in organisms of plants,insects,and vertebrates.It has been approved that antimicrobial peptides have broad spectrum antimicrobial activities,and play a ...Antimicrobial peptides are widely distributed in nature,existing in organisms of plants,insects,and vertebrates.It has been approved that antimicrobial peptides have broad spectrum antimicrobial activities,and play a key modulatory role in the innate immune response and tumor inhibiting activity.Due to the special action mechanism,the antimicrobial peptides become a hot field of genetic engineering.In the present paper,the general properties,mechanism of action,application value,existing problems,the latest progress and the expression strategy were discussed.展开更多
Herein,this article was focused on the synthesis and discussed the spectroscopic characterizations of four new scandium(Ⅲ)sulfa-drug complexes.The nomenclature and symbols of these drugs were sulfadimidine(sulp-1),su...Herein,this article was focused on the synthesis and discussed the spectroscopic characterizations of four new scandium(Ⅲ)sulfa-drug complexes.The nomenclature and symbols of these drugs were sulfadimidine(sulp-1),sulfanilamide(sulp-2),sulfamethoxazole(sulp-3)and sulfadiazine(sulp-4).The microanalytical and spectroscopic analyses which utilized in this study were micro-analyses,magnetic,FT-IR,UV-Vis techniques.The mid infrared spectra deduced that the four sulfa-drug chelates acts as a bidentate chelates with scandium(Ⅲ)ion via two nitrogen atoms of-NH2-Ar and-NH-SO2 groups.Also,the FTIR spectra of Sc3+complexes referred to the existed of new medium weak bands in the range of 500~400 cm^-1 due to stretching vibration bands ofν(M-N).The elemental analysis technique confirmed the 1∶2 stoichiometry between Sc3+ions and sulp ligand with molecular formula[Sc(sulp)2(Cl)2]·Cl.At room temperature,the results of magnetic measurements for the Sc(Ⅲ)complexes indicated that all of the synthesized complexes have a diamagnetic character with octahedral configuration.The electronic spectra of the free sulfa-drug ligands shows band at 275 and 310 nm which are intraligand charge transfer band.The electronic sbsorption spectra of the Sc3+complexes were recorded using DMSO solvent.The spectra of complexes display bands within 275~388 nm,which attributed toπ-π*,n-π*and charge-transfer M-LCT electronic transitions,which strongly favors the octahedral geometry around Sc(Ⅲ)metal ions.1HNMR spectra of complexes referred to the downfield proton shifts of the-NH2 and NHSO2 groups,which supported the place of coordination.The half maximal inhibitory concentration(IC50)of the ScⅢcomplexes was assessed against the human hepato cellular carcinoma(HepG-2)tumor cell line.展开更多
The volatile oil of leaves and barks of Calycopteris floribunda was examined by gas chromatography-mass spectrometry (GC-MS). 52 volatile chemical components in leaves were identified. The antimicrobial assay of oils ...The volatile oil of leaves and barks of Calycopteris floribunda was examined by gas chromatography-mass spectrometry (GC-MS). 52 volatile chemical components in leaves were identified. The antimicrobial assay of oils in the leaves and barks was carried out by disk diffusion method in vitro. The major components (mass fraction) in leaves are caryophyllene oxide (13.79%),n-hexadecanoic acid (11.91%) and β-caryophyllene (10.45%). Ten constituents are identified accounting for about 99.98% of the total volatile oil in the bark. Among these components,n-hexadecanoic acid (59.18%),linolic acid (12.70%) and butyl octyl phthalate (8.21%) are the major constituents. The oils exhibit strong antimicrobial activity and display more potent against bacteria than fungi.展开更多
OBJECTIVE Metrnl is a novel secreted protein with limited researches.In this study,we investigated metrnl tissue expression pattern in humans,and exploredthe possible role of its highest expression using animal models...OBJECTIVE Metrnl is a novel secreted protein with limited researches.In this study,we investigated metrnl tissue expression pattern in humans,and exploredthe possible role of its highest expression using animal models.METHODS We examined metrnl tissue expression pattern in a human tissue microarray containing 19types of tissues from 69 donors,and verified the highest expression in fresh human and mouse tissues.We then created an animal model of cell-specific knockout mice to study the role of metrnl.RESULTS Metrnl was the highest expressed in human gastrointestinal tract,and specifical y expressed in the intestinal epithelium.Consistently,Metrnl expression was also the highest expressed in mouse gastrointestinal tract among the detected tissues of 14 types.We developed intestinal epithelial cellspecific metrnl knockout mice with Vil in-Cre.In this animal model,metrnl levels displayed a statistically significant reduction in gut fluid,but not in blood serum.This cell specific deletion of metrnl did not affect body weight,food intake,blood glucose,colon length and histology,intestinal permeability,mucus production and mucin 2 expression under physiological conditions,but markedly reduced the expression of antimicrobial peptides,such as regenerating islet-derived 3 gamma and lactotransferrin.CONCLUSION Metrnl is rich in intestinal epithelial cells of humans and mice,mainly contributing to local gut metrnl level,and less affecting systemic circulating metrnl level.Metrnl plays a role in maintaining gut antimicrobial peptides.展开更多
Te(Ⅳ),Se(Ⅳ),V(Ⅲ),Nb(Ⅴ)and Ta(Ⅴ)complexes of indole-3-acetic acid(IAAH)ligand were synthesized,characterized by elemental analysis and various spectroscopic techniques like,IR,1H-NMR,X-ray powder diffraction,UV-Vi...Te(Ⅳ),Se(Ⅳ),V(Ⅲ),Nb(Ⅴ)and Ta(Ⅴ)complexes of indole-3-acetic acid(IAAH)ligand were synthesized,characterized by elemental analysis and various spectroscopic techniques like,IR,1H-NMR,X-ray powder diffraction,UV-Visible,thermogravimetry analysis,magnetic measurements,molar conductance and surface morphology using SEM.All the synthesized complexes of IAAH ligand have 1∶2 stoichiometry of the types[Te(IAA)2(NH 3)2]·2Cl(Ⅰ),[Se(IAA)2(NH 3)2]·2Cl(Ⅱ),[V(IAA)2(NH 3)(Cl)](Ⅲ),[Nb(IAA)2(Cl)3](Ⅳ),and[Ta(IAA)2(Cl)3](Ⅴ).Spectral analysis indicates octahedral geometry for the Te(Ⅳ),Se(Ⅳ)and V(Ⅲ)complexes,whereas both Nb(Ⅴ)and Ta(Ⅴ)have a seven-coordination.The bonding sites are the oxygen atoms of carboxylate group for the deprotonated indole-3-acetic acid(IAA)ligand.The thermogravimetry analysis studies gave evidence for the presence of other coordinated molecules(Cl or NH 3)in the composition of IAA complexes,which were further supported by IR and micro analytical measurements.The higher molar conductance data of tellurium and selenium(Ⅳ)complexes reveal that these chelates are electrolytes,while low conductivity values for the vanadium(Ⅲ),niobium and tantalum(Ⅴ)chelates indicated a non-electrolytes.To test the antibacterial property of the five complexes in this study,four bacterial strains Klebsiella(G-),Escherichia coli(G-),Staphylococcus aureus(G+)and Staphylococcus epidermidis(G+)were used in the investigation.The effects of the five complexes in the cytotoxicity of Caco-2 and Mcf-7 human cancer cell lines were studied Neutral red uptake assay for the estimation of cell viability/cytotoxicity protocol.展开更多
2,4-Dichlorophenoxyacetic acid(2,4-D)is a board-leaf selective herbicide and globally used in agricultural activities.Complexation mode,spectroscopic investigations and biological properties of complexes formed betwee...2,4-Dichlorophenoxyacetic acid(2,4-D)is a board-leaf selective herbicide and globally used in agricultural activities.Complexation mode,spectroscopic investigations and biological properties of complexes formed between 2,4-D(C_(6)H_(3)Cl_(2)OCH_(2)·COOH;HL)with Zn(Ⅱ),Cu(Ⅱ),Ni(Ⅱ),Co(Ⅱ),and Mn(Ⅱ)metal ions were investigated.To characterize the binding mode between 2,4-D and the metal ions,many physicochemical approaches were employed.The complexes obtained are characterized quantitatively and qualitatively by using micro elemental analysis,FTIR spectroscopy,UV-Vis spectroscopy,1H-NMR,and magnetic susceptibility measurements.Results of these approaches suggested that the gross formula of the complexes obtained with the metal ions were[ZnL_(2)](2H_(2)O(1),[CuL_(2)(H_(2)O)_(2)](2),[NiL_(2)](3H_(2)O(3),[CoL_(2)(H_(2)O)_(2)](4),and[MnL_(2)(H_(2)O)_(2)](5).In all complexes,two L-anion were coordinated the metal ion by their bidentate carboxylate groups.From the spectral study,all the complexes obtained as monomeric structure and the metals center moieties are six-coordinated with octahedral geometry except Ni(Ⅱ)and Zn(Ⅱ)complexes which existed as a tetrahedral and square pyramidal geometry respectively.The complexes were screened in vitro against several microbes(fungi and bacteria)using Kirby-Bauer disc diffusion method,and data has demonstrated that complex 3 showed excellent antifungal activity.展开更多
As a strategy for phytopathogen control throughtransgenic way,antimicrobial peptide genes havebeen employed over the last two decades.CEMA is a cationic antimicrobial chimericpeptide,which is produced by fusing eighta...As a strategy for phytopathogen control throughtransgenic way,antimicrobial peptide genes havebeen employed over the last two decades.CEMA is a cationic antimicrobial chimericpeptide,which is produced by fusing eightamino acid residues from the antimicrobialpeptide ceropin A with a modified meltin.Threetransgenic cotton plants were generated展开更多
OBJECTIVE To evaluate the in vivo anti-inflammatory and allergic rhinitis(AR)alleviating effect as well as in vitro antimicrobial activities of Artemisia ordosica Krasch.(AOK)extracts to verify its ethno-medicinal cla...OBJECTIVE To evaluate the in vivo anti-inflammatory and allergic rhinitis(AR)alleviating effect as well as in vitro antimicrobial activities of Artemisia ordosica Krasch.(AOK)extracts to verify its ethno-medicinal claims.METHODS Crude extracts(methanol/95%-ethanol/ethyl acetate)of AOK root/stem/leaf and fractions(petroleum ether/ethyl acetate/n-butanol/aqueous)of AOK root extractwere prepared.Xylene-induced ear swelling model in mouse and ovalbumin(OVA)-induced AR model in guinea pig were established.Ear swelling degrees of mice were measured.The numbers of rubbing movement and sneezes of guinea pigs were counted to evaluate the symptoms of AR.The serum levels of histamine,INF-γ,IL-2/4/10,and VCAM-1 were measured by ELISA assay.The histological changes of nasal mucosa were investigated by light microscope after H&E staining.Antimicrobial activities of AOK extracts were also tested.LC-MS/MS analysis was performed to characterize the constituents of active extract and molecular docking was conducted to predict the biological mechanism.RESULTS In ear-swelling model,extract(100.00 mg·kg^-1)from the ethyl acetate layer of 95%ethanol(100.00 mg·kg^-1)showed better swelling inhibition in mice than positive control(dexamethasone,191.91 mg·kg^-1).In AR model,extract from the ethyl acetate layer of 95%ethanol significantly alleviated the AR symp⁃toms in guinea pigs,decreased the serum levels of histamine,INF-γ,IL-2/4/10,and VCAM-1,and reduced the infiltration of eosinophil in nasal mucosa.For Staphylococcus aureus,the ethyl acetate extract of AOK stem showed the highest inhibi⁃tion(MIC=1.25 g·L^-1),for Escherichia coli,n-butanol layer of 95%ethanol extract of AOK root showed the highest inhibi⁃tion(MIC=15.00 g·L^-1),for Candida glabrata,95%-ethanol extract of AOK stem showed the best inhibition(MIC=0.064 g·L^-1),while ethyl acetate and n-butanol layers showed similar inhibition on MRSA(MIC=7.50 g·L-1).LC-MS/MS characteriza⁃tion showed that dicaffeoylquinic acids account for more than 30%of ethyl acetate layer of AOK extract.Dicaffeoylquinic acids bind with histamine-1 receptor with high affinities and interesting modes.CONCLUSION Extracts from AOK had interesting anti-inflammatory activity in mice,alleviating effect against OVA-induced AR in guinea pigs,and antimicrobial activities in vitro,which support the ethno-medicinal use of it.The main constituents in ethyl acetate layer of AOK root extract are dicaffeoylquinic acids and could bind with histamine-1 receptor well.These findings highlighted the impor⁃tance of natural product chemistry study of AOK.展开更多
OBJECTIVE To isolate and characterize bioactive compound from traditionally important medicinal plant Mikania cordata,and to investigate muti-faced pharmacological activities of the isolated compound.METHODS A triterp...OBJECTIVE To isolate and characterize bioactive compound from traditionally important medicinal plant Mikania cordata,and to investigate muti-faced pharmacological activities of the isolated compound.METHODS A triterpeenoid,16-hydroxy betulinic acid(16 HBA) was isolated from Mikania cordata leaf and the structure of the compound was determined by NMR spectroscopic means.Antimicrobial activity of 16 HBA was tested by disc diffusion method and minimum inhibitory concentration(MIC) against the tested microorganisms was determined.The analgesic property of 16 HBA was tested using acetic acid-induced writhes in mice and hot plate thermal stimulation in rats.The anti-inflammatory activity was studied using carrageenin-induced paw edema method.The antipyretic potential of 16 HBA was evaluated by using yeast-induced hyperthermia in rats.RESULTS The triterpenoid 16 HBA showed potent antibacterial activity with inhibition zone of diameter ranging from 12.0~17.5 mm and antifungal activity with mycelial growth inhibition ranges from 37.6%~54.5%.The MIC values for antibacterial and antifungal activities ranged from 31.5~125 and 250~1000 μg·mL-1 respectively.The compound(50 and100 mg·kg^(-1) body weight) showed potent peripheral and central analgesic activity having 55.19% and41% of writhing inhibition at 90 min after administration of the compound and the highest 55.98%,79.18% elongation of reaction time,respectively.In anti-inflammatory activity screening,the compound(100 mg·kg^(-1)) revealed the highest 77.08% edema inhibition at 4 h after administration of carrageenan.In antipyretic assay,16 HBA exhibited a strong antipyretic effect in yeast-induced rats.CONCLUSION The present study confirmed that 16-hydroxy betulinic acid isolated from Mikania cordata has potent antimicrobial,analgesic,anti-inflammatory and antipyretic properties.Our results can be seen as scientific support for the traditional and folklore usage of Mikania cordata in Bangladesh for the treatment of different ailments and provide opportunities to explore this plant as a source bioactive compounds for biochemical and pharmaceutical industries.展开更多
Increasing evidences indicate that male haploid are more susceptible to parasites than female diploid(workers,alate females and queens)although the generality and reasons causing such susceptibility are still under de...Increasing evidences indicate that male haploid are more susceptible to parasites than female diploid(workers,alate females and queens)although the generality and reasons causing such susceptibility are still under debate.The male haploids in eusocial Hymenoptera are perfect for examining the susceptibility assumption and unveiling the molecular mechanisms of this assumption.In the present study,the males,workers and alate females of red imported fire ants(Solenopsis invicta)were challenged with entomopathogenic fungus Metarrhizium anisopliae.By measuring the LC50 values of M.anisopliae against different castes of S.invicta,we found that haploid males suffered from reduced disease resistance than diploid workers and alate females,a proof that haploid susceptibility was diminished in S.invicta.In this study we also examined the assumption that males invest less in innate immunity contributing to haploid susceptibility based on the transcript levels of genes encoding antimicrobial peptides(AMP)with quantitative reverse transcription-PCR(qRT-PCR).We found that infection increased the mRNA levels of hymenoptaecin in females(workers and alate females),but not in males;no significant difference was found in the mRNA levels of defensin,transferrin or crustin between infected ants and control ants in each sxe/castes.However,this study suggested that any resistance traits like behavioral and other immunological responses,are contributing to haploid susceptibility.展开更多
A new alkaloid,diacedolinate(1),along with fourteen known compounds(2-15)was isolated from the sponge associated fungus Penicillium crustosum SCSIO 41442.The structures of these compounds were determined by spectrum a...A new alkaloid,diacedolinate(1),along with fourteen known compounds(2-15)was isolated from the sponge associated fungus Penicillium crustosum SCSIO 41442.The structures of these compounds were determined by spectrum analysis and ECD.All compounds were evaluated for their antioxidant and antimicrobial activities.The results showed that compound 1 exhibited weak antioxidant activity with an IC_(50)value of(71.00±0.14)μg·mL^(−1),while compound 2,in contrast,displayed broad antioxidant activity with an IC_(50)value of(1.25±0.10)μg·mL^(−1),compared with the positive control,vitamin C.In addition,compounds 9,10,11,and 15 demonstrated broad-spectrum antimicrobial activity against a variety of pathogens,including MRSA,Colletotrichum asianum HNM 408,Colletotrichum acutatum HNM RC178,and Alternaria alternate,with MIC values ranging from 2.5 to 160μg·mL^(−1).The bioactivities of these compounds are reported here for the first time.展开更多
基金Projects(41827805,41976044)supported by the National Natural Science Foundation of ChinaProject(ZDYF2021GXJS210)supported by the Hainan Provincial Science and Technology Special Fund,China+2 种基金Project(2021CXLH0005)supported by the Hainan Provincial Joint Project of Sanya Yazhou Bay Science and Technology City,ChinaProject(2021WHZZB2301)supported by the Wenhai Program of the S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology,ChinaProject(121311KYSB20210005)supported by the Overseas Science and Education Centers of Bureau of International Cooperation Chinese Academy of Sciences。
文摘Microarc oxidation is an effective surface treatment for improving certain properties of metals and their alloys.In this paper,TiO_(2)/Cu_(2)O and TiO_(2)/Cu_(2)O@CeO_(2)coatings were prepared on Ti-6Al-4V by microarc oxidation.Thecoatings exhibited good corrosion resistance and antimicrobial properties.X-ray diffraction(XRD),scanning electronmicroscopy(SEM),and 3D laser confocal were used to characterize the coatings.The properties of TiO_(2)/Cu_(2)O and TiO_(2)/Cu_(2)O@CeO_(2)coatings were analyzed,including microstructure,surface roughness,corrosion resistance,andantimicrobial properties.The electrochemical results showed that the coatings prepared by microarc oxidation hadenhanced corrosion resistance compared to the substrate.The antibacterial properties of TiO_(2)/Cu_(2)O and TiO_(2)/Cu_(2)O@CeO_(2)coating against Pseudomonas aeruginosa were evaluated by fluorescence microscopy and plate counting.The antibacterial rate of TiO_(2)/Cu_(2)O@CeO_(2)coating was up to 99.70%.In summary,the TiO_(2)/Cu_(2)O and TiO_(2)/Cu_(2)O@CeO_(2)coatings prepared by microarc oxidation have a potential application background in the field of marine corrosionprotection and biofouling.
文摘The structure, properties and application to water-soluble coatings of a new complex antimicrobial agent Ag-carboxylmethyl citosan-thiabendazole （Ag-CMCTS-TBZ） prepared from different materiel ratios were reported. The silver ions were preferably coordinated with the free-NH2 groups and the -OH groups of secondary alcohol and carboxyl in CMCTS. TBZ preferably bonded to carboxyl group in CMCTS by electrostatic force and hydrogen bonding. Increase in silver ions content in the complex agent improved to some limited extent the antibacterial activity, but enhanced coloring and cost of the complex agent. Increase in TBZ content resulted in increase of antifungal activity, but decrease of water solubility of the complex agent. The antimicrobial MICs of the complex agent to Esherichia coil, Staphylococcus aureus, Candida albicans, Aspergillus niger, Mucor sp. were 20 -80, 15 -60, 20 - 55, 40 - 250, and 400 - 1700 mg/kg, respectively. Addition of 0.1% of this complex agent to acrylic emulsion paint made the paint without substantial change in color, luster, viscosity, odor or pH value, but with an excellent and chronically persisting broad-spectra antimicrobial activity.
文摘The liquid ion exchange method, solid salt melt method and dry-wet circulation method were used to prepare natural porous antimicrobial materials with natural minerals, such as zeolite, spilite, palygorskite and montmorillonite, respectively. Atomic absorption spectrum and X-ray diffraction analysis were carried out to investigate the effects of Ag^＋ , Cu^2＋ and Zn^2＋ on antimicrobial abilities of natural porous minerals, and the effect of preparation method on ion exchange capacity of antimicrobial material, respectively. The results show that for the ion exchange capacity, clay mineral is higher than fibrous mineral, i.e. both zeolite and montmorillonite are higher; the antimicrobial ability of material with Ag^＋ is the bests the exchange capacities of materials with Cu^2＋ or Zn^2＋ are all higher, but the antimicrobial ability of Cu^2＋ is better than that of Zn^2＋ .
基金Supported by National 863 Project of China (2006AA10A206)
文摘Antimicrobial peptides are widely distributed in nature,existing in organisms of plants,insects,and vertebrates.It has been approved that antimicrobial peptides have broad spectrum antimicrobial activities,and play a key modulatory role in the innate immune response and tumor inhibiting activity.Due to the special action mechanism,the antimicrobial peptides become a hot field of genetic engineering.In the present paper,the general properties,mechanism of action,application value,existing problems,the latest progress and the expression strategy were discussed.
文摘Herein,this article was focused on the synthesis and discussed the spectroscopic characterizations of four new scandium(Ⅲ)sulfa-drug complexes.The nomenclature and symbols of these drugs were sulfadimidine(sulp-1),sulfanilamide(sulp-2),sulfamethoxazole(sulp-3)and sulfadiazine(sulp-4).The microanalytical and spectroscopic analyses which utilized in this study were micro-analyses,magnetic,FT-IR,UV-Vis techniques.The mid infrared spectra deduced that the four sulfa-drug chelates acts as a bidentate chelates with scandium(Ⅲ)ion via two nitrogen atoms of-NH2-Ar and-NH-SO2 groups.Also,the FTIR spectra of Sc3+complexes referred to the existed of new medium weak bands in the range of 500~400 cm^-1 due to stretching vibration bands ofν(M-N).The elemental analysis technique confirmed the 1∶2 stoichiometry between Sc3+ions and sulp ligand with molecular formula[Sc(sulp)2(Cl)2]·Cl.At room temperature,the results of magnetic measurements for the Sc(Ⅲ)complexes indicated that all of the synthesized complexes have a diamagnetic character with octahedral configuration.The electronic spectra of the free sulfa-drug ligands shows band at 275 and 310 nm which are intraligand charge transfer band.The electronic sbsorption spectra of the Sc3+complexes were recorded using DMSO solvent.The spectra of complexes display bands within 275~388 nm,which attributed toπ-π*,n-π*and charge-transfer M-LCT electronic transitions,which strongly favors the octahedral geometry around Sc(Ⅲ)metal ions.1HNMR spectra of complexes referred to the downfield proton shifts of the-NH2 and NHSO2 groups,which supported the place of coordination.The half maximal inhibitory concentration(IC50)of the ScⅢcomplexes was assessed against the human hepato cellular carcinoma(HepG-2)tumor cell line.
基金Project(2007-1718) supported by Development and Reform Commission of Yunnan Province, China
文摘The volatile oil of leaves and barks of Calycopteris floribunda was examined by gas chromatography-mass spectrometry (GC-MS). 52 volatile chemical components in leaves were identified. The antimicrobial assay of oils in the leaves and barks was carried out by disk diffusion method in vitro. The major components (mass fraction) in leaves are caryophyllene oxide (13.79%),n-hexadecanoic acid (11.91%) and β-caryophyllene (10.45%). Ten constituents are identified accounting for about 99.98% of the total volatile oil in the bark. Among these components,n-hexadecanoic acid (59.18%),linolic acid (12.70%) and butyl octyl phthalate (8.21%) are the major constituents. The oils exhibit strong antimicrobial activity and display more potent against bacteria than fungi.
基金The project supported by National Natural Science Foundation of China(81130061,81202572,81373414)
文摘OBJECTIVE Metrnl is a novel secreted protein with limited researches.In this study,we investigated metrnl tissue expression pattern in humans,and exploredthe possible role of its highest expression using animal models.METHODS We examined metrnl tissue expression pattern in a human tissue microarray containing 19types of tissues from 69 donors,and verified the highest expression in fresh human and mouse tissues.We then created an animal model of cell-specific knockout mice to study the role of metrnl.RESULTS Metrnl was the highest expressed in human gastrointestinal tract,and specifical y expressed in the intestinal epithelium.Consistently,Metrnl expression was also the highest expressed in mouse gastrointestinal tract among the detected tissues of 14 types.We developed intestinal epithelial cellspecific metrnl knockout mice with Vil in-Cre.In this animal model,metrnl levels displayed a statistically significant reduction in gut fluid,but not in blood serum.This cell specific deletion of metrnl did not affect body weight,food intake,blood glucose,colon length and histology,intestinal permeability,mucus production and mucin 2 expression under physiological conditions,but markedly reduced the expression of antimicrobial peptides,such as regenerating islet-derived 3 gamma and lactotransferrin.CONCLUSION Metrnl is rich in intestinal epithelial cells of humans and mice,mainly contributing to local gut metrnl level,and less affecting systemic circulating metrnl level.Metrnl plays a role in maintaining gut antimicrobial peptides.
基金the Deanship of Scientific Research at Princess Nourah bint Abdulrahman University,through the Research Groups Program Grant no.(RGP-1440-0001)。
文摘Te(Ⅳ),Se(Ⅳ),V(Ⅲ),Nb(Ⅴ)and Ta(Ⅴ)complexes of indole-3-acetic acid(IAAH)ligand were synthesized,characterized by elemental analysis and various spectroscopic techniques like,IR,1H-NMR,X-ray powder diffraction,UV-Visible,thermogravimetry analysis,magnetic measurements,molar conductance and surface morphology using SEM.All the synthesized complexes of IAAH ligand have 1∶2 stoichiometry of the types[Te(IAA)2(NH 3)2]·2Cl(Ⅰ),[Se(IAA)2(NH 3)2]·2Cl(Ⅱ),[V(IAA)2(NH 3)(Cl)](Ⅲ),[Nb(IAA)2(Cl)3](Ⅳ),and[Ta(IAA)2(Cl)3](Ⅴ).Spectral analysis indicates octahedral geometry for the Te(Ⅳ),Se(Ⅳ)and V(Ⅲ)complexes,whereas both Nb(Ⅴ)and Ta(Ⅴ)have a seven-coordination.The bonding sites are the oxygen atoms of carboxylate group for the deprotonated indole-3-acetic acid(IAA)ligand.The thermogravimetry analysis studies gave evidence for the presence of other coordinated molecules(Cl or NH 3)in the composition of IAA complexes,which were further supported by IR and micro analytical measurements.The higher molar conductance data of tellurium and selenium(Ⅳ)complexes reveal that these chelates are electrolytes,while low conductivity values for the vanadium(Ⅲ),niobium and tantalum(Ⅴ)chelates indicated a non-electrolytes.To test the antibacterial property of the five complexes in this study,four bacterial strains Klebsiella(G-),Escherichia coli(G-),Staphylococcus aureus(G+)and Staphylococcus epidermidis(G+)were used in the investigation.The effects of the five complexes in the cytotoxicity of Caco-2 and Mcf-7 human cancer cell lines were studied Neutral red uptake assay for the estimation of cell viability/cytotoxicity protocol.
基金the deanship of scientific Research at Princess Nourah bint Abdulrahman University through the Fast-track Research Funding program。
文摘2,4-Dichlorophenoxyacetic acid(2,4-D)is a board-leaf selective herbicide and globally used in agricultural activities.Complexation mode,spectroscopic investigations and biological properties of complexes formed between 2,4-D(C_(6)H_(3)Cl_(2)OCH_(2)·COOH;HL)with Zn(Ⅱ),Cu(Ⅱ),Ni(Ⅱ),Co(Ⅱ),and Mn(Ⅱ)metal ions were investigated.To characterize the binding mode between 2,4-D and the metal ions,many physicochemical approaches were employed.The complexes obtained are characterized quantitatively and qualitatively by using micro elemental analysis,FTIR spectroscopy,UV-Vis spectroscopy,1H-NMR,and magnetic susceptibility measurements.Results of these approaches suggested that the gross formula of the complexes obtained with the metal ions were[ZnL_(2)](2H_(2)O(1),[CuL_(2)(H_(2)O)_(2)](2),[NiL_(2)](3H_(2)O(3),[CoL_(2)(H_(2)O)_(2)](4),and[MnL_(2)(H_(2)O)_(2)](5).In all complexes,two L-anion were coordinated the metal ion by their bidentate carboxylate groups.From the spectral study,all the complexes obtained as monomeric structure and the metals center moieties are six-coordinated with octahedral geometry except Ni(Ⅱ)and Zn(Ⅱ)complexes which existed as a tetrahedral and square pyramidal geometry respectively.The complexes were screened in vitro against several microbes(fungi and bacteria)using Kirby-Bauer disc diffusion method,and data has demonstrated that complex 3 showed excellent antifungal activity.
文摘As a strategy for phytopathogen control throughtransgenic way,antimicrobial peptide genes havebeen employed over the last two decades.CEMA is a cationic antimicrobial chimericpeptide,which is produced by fusing eightamino acid residues from the antimicrobialpeptide ceropin A with a modified meltin.Threetransgenic cotton plants were generated
基金Science Foundation of Inner Mongolia(2017MS0870)Science and Technology Planning Project of Inner Mongolia(201702139)
文摘OBJECTIVE To evaluate the in vivo anti-inflammatory and allergic rhinitis(AR)alleviating effect as well as in vitro antimicrobial activities of Artemisia ordosica Krasch.(AOK)extracts to verify its ethno-medicinal claims.METHODS Crude extracts(methanol/95%-ethanol/ethyl acetate)of AOK root/stem/leaf and fractions(petroleum ether/ethyl acetate/n-butanol/aqueous)of AOK root extractwere prepared.Xylene-induced ear swelling model in mouse and ovalbumin(OVA)-induced AR model in guinea pig were established.Ear swelling degrees of mice were measured.The numbers of rubbing movement and sneezes of guinea pigs were counted to evaluate the symptoms of AR.The serum levels of histamine,INF-γ,IL-2/4/10,and VCAM-1 were measured by ELISA assay.The histological changes of nasal mucosa were investigated by light microscope after H&E staining.Antimicrobial activities of AOK extracts were also tested.LC-MS/MS analysis was performed to characterize the constituents of active extract and molecular docking was conducted to predict the biological mechanism.RESULTS In ear-swelling model,extract(100.00 mg·kg^-1)from the ethyl acetate layer of 95%ethanol(100.00 mg·kg^-1)showed better swelling inhibition in mice than positive control(dexamethasone,191.91 mg·kg^-1).In AR model,extract from the ethyl acetate layer of 95%ethanol significantly alleviated the AR symp⁃toms in guinea pigs,decreased the serum levels of histamine,INF-γ,IL-2/4/10,and VCAM-1,and reduced the infiltration of eosinophil in nasal mucosa.For Staphylococcus aureus,the ethyl acetate extract of AOK stem showed the highest inhibi⁃tion(MIC=1.25 g·L^-1),for Escherichia coli,n-butanol layer of 95%ethanol extract of AOK root showed the highest inhibi⁃tion(MIC=15.00 g·L^-1),for Candida glabrata,95%-ethanol extract of AOK stem showed the best inhibition(MIC=0.064 g·L^-1),while ethyl acetate and n-butanol layers showed similar inhibition on MRSA(MIC=7.50 g·L-1).LC-MS/MS characteriza⁃tion showed that dicaffeoylquinic acids account for more than 30%of ethyl acetate layer of AOK extract.Dicaffeoylquinic acids bind with histamine-1 receptor with high affinities and interesting modes.CONCLUSION Extracts from AOK had interesting anti-inflammatory activity in mice,alleviating effect against OVA-induced AR in guinea pigs,and antimicrobial activities in vitro,which support the ethno-medicinal use of it.The main constituents in ethyl acetate layer of AOK root extract are dicaffeoylquinic acids and could bind with histamine-1 receptor well.These findings highlighted the impor⁃tance of natural product chemistry study of AOK.
基金supported by Centre for Biomedical Research,University of Dhaka and Department of Applied Chemistry&Chemical Technology,Islamic University,Kushtia,Bangladesh
文摘OBJECTIVE To isolate and characterize bioactive compound from traditionally important medicinal plant Mikania cordata,and to investigate muti-faced pharmacological activities of the isolated compound.METHODS A triterpeenoid,16-hydroxy betulinic acid(16 HBA) was isolated from Mikania cordata leaf and the structure of the compound was determined by NMR spectroscopic means.Antimicrobial activity of 16 HBA was tested by disc diffusion method and minimum inhibitory concentration(MIC) against the tested microorganisms was determined.The analgesic property of 16 HBA was tested using acetic acid-induced writhes in mice and hot plate thermal stimulation in rats.The anti-inflammatory activity was studied using carrageenin-induced paw edema method.The antipyretic potential of 16 HBA was evaluated by using yeast-induced hyperthermia in rats.RESULTS The triterpenoid 16 HBA showed potent antibacterial activity with inhibition zone of diameter ranging from 12.0~17.5 mm and antifungal activity with mycelial growth inhibition ranges from 37.6%~54.5%.The MIC values for antibacterial and antifungal activities ranged from 31.5~125 and 250~1000 μg·mL-1 respectively.The compound(50 and100 mg·kg^(-1) body weight) showed potent peripheral and central analgesic activity having 55.19% and41% of writhing inhibition at 90 min after administration of the compound and the highest 55.98%,79.18% elongation of reaction time,respectively.In anti-inflammatory activity screening,the compound(100 mg·kg^(-1)) revealed the highest 77.08% edema inhibition at 4 h after administration of carrageenan.In antipyretic assay,16 HBA exhibited a strong antipyretic effect in yeast-induced rats.CONCLUSION The present study confirmed that 16-hydroxy betulinic acid isolated from Mikania cordata has potent antimicrobial,analgesic,anti-inflammatory and antipyretic properties.Our results can be seen as scientific support for the traditional and folklore usage of Mikania cordata in Bangladesh for the treatment of different ailments and provide opportunities to explore this plant as a source bioactive compounds for biochemical and pharmaceutical industries.
文摘Increasing evidences indicate that male haploid are more susceptible to parasites than female diploid(workers,alate females and queens)although the generality and reasons causing such susceptibility are still under debate.The male haploids in eusocial Hymenoptera are perfect for examining the susceptibility assumption and unveiling the molecular mechanisms of this assumption.In the present study,the males,workers and alate females of red imported fire ants(Solenopsis invicta)were challenged with entomopathogenic fungus Metarrhizium anisopliae.By measuring the LC50 values of M.anisopliae against different castes of S.invicta,we found that haploid males suffered from reduced disease resistance than diploid workers and alate females,a proof that haploid susceptibility was diminished in S.invicta.In this study we also examined the assumption that males invest less in innate immunity contributing to haploid susceptibility based on the transcript levels of genes encoding antimicrobial peptides(AMP)with quantitative reverse transcription-PCR(qRT-PCR).We found that infection increased the mRNA levels of hymenoptaecin in females(workers and alate females),but not in males;no significant difference was found in the mRNA levels of defensin,transferrin or crustin between infected ants and control ants in each sxe/castes.However,this study suggested that any resistance traits like behavioral and other immunological responses,are contributing to haploid susceptibility.
文摘A new alkaloid,diacedolinate(1),along with fourteen known compounds(2-15)was isolated from the sponge associated fungus Penicillium crustosum SCSIO 41442.The structures of these compounds were determined by spectrum analysis and ECD.All compounds were evaluated for their antioxidant and antimicrobial activities.The results showed that compound 1 exhibited weak antioxidant activity with an IC_(50)value of(71.00±0.14)μg·mL^(−1),while compound 2,in contrast,displayed broad antioxidant activity with an IC_(50)value of(1.25±0.10)μg·mL^(−1),compared with the positive control,vitamin C.In addition,compounds 9,10,11,and 15 demonstrated broad-spectrum antimicrobial activity against a variety of pathogens,including MRSA,Colletotrichum asianum HNM 408,Colletotrichum acutatum HNM RC178,and Alternaria alternate,with MIC values ranging from 2.5 to 160μg·mL^(−1).The bioactivities of these compounds are reported here for the first time.
