AIM： To investigate the increasing the susceptibility pylon） to metronidazole. mechanisms of aspirin of Helicobacter pylori （H METHODS： Hpylori reference strain 26695 and two metronidazole-resistant isolates of H ...AIM： To investigate the increasing the susceptibility pylon） to metronidazole. mechanisms of aspirin of Helicobacter pylori （H METHODS： Hpylori reference strain 26695 and two metronidazole-resistant isolates of H pylori were included in this study. Strains were incubated in Brucella broth with or without aspirin （1 mmol/L）. The rdxA gene of Hpylori was amplified by PCR and sequenced. The permeability of Hpylori to antimicrobials was determined by analyzing the endocellular radioactivity of the cells after incubated with [7-^3H]-tetracycline. The outer membrane proteins （OMPs） of Hpylori 26695 were depurated and analyzed by SDS-PAGE. The expression of 5 porins （hopA, hopB, hopC, hopD and hopE） and the putative RND efflux system （hefABC） of H pylori were analyzed using real-time quantitative PCR. RESULTS： The mutations in rdxA gene did not change in metronidazole resistant isolates treated with aspirin. The radioactivity of H pylori increased when treated with aspirin, indicating that aspirin improved the permeability of the outer membrane of H pylori. However, the expression of two OMP bands between 55 kDa and 72 kDa altered in the presence of aspirin.The expression of the mRNA of hopA, hopB, hopC, hopD, hopE and herA, hefB, hefC of H pylori did not change when treated with aspirin. CONCLUSION： Although aspirin increases the susceptibility of H pylori to metronidazole, it has no effect on the mutations of rdxA gene of Hpylori. Aspirin increases endocellular concentrations of antimicrobials probably by altering the OMP expression.展开更多
[Objectives] This study was conducted to explore the antifungal activity of wood vinegar produced from apricot shell. [Methods]The minimal inhibitory concentration（ MIC） of wood vinegar against Aspergillus fumigatus...[Objectives] This study was conducted to explore the antifungal activity of wood vinegar produced from apricot shell. [Methods]The minimal inhibitory concentration（ MIC） of wood vinegar against Aspergillus fumigatus was determined on agar plates. Then,the mycelial growth and the morphology of the apical vesicles of A. fumigatus cultured in the medium supplemented with 1/2 MIC wood vinegar were observed to evaluate the effect of wood vinegar on A. fumigatus.RNA-Seq was performed to explore the antifungal mechanism of wood vinegar. [Results] The wood vinegar produced from apricot shell could inhibit the growth of A. fumigatus,with a MIC of 20 μl/ml. In the medium supplemented with 1/2 MIC wood vinegar,the mycelial growth of A. fumigatus was suppressed,some apical vesicles were incompletely developed. The gene ontology（ GO） term enrichment analysis based on RNA-Seq showed that the differentially expressed genes（ DEGs）were enriched in metabolic process,cellular process and single-organism process in the category of biological processes,cell,cell part,membrane,organelle and membrane part in the category of cellular components,catalytic activity and binding in the category of molecular function. The significantly up-regulated DEGs were mostly involved in cell,cell part,organelle,organelle part and macro molecular complex in the category of cellular component,while the significantly down-regulated DEGs were mostly involved in biological process,cellular process and single-organism process in the category of biological process,catalytic activity,binding,transporter activity,and nucleic acid binding transcription factor activity in the category molecular function. Moreover,KEGG（ Kyoto Encyclopedia of Genes and Genomes） pathway analysis showed that the DEG unigenes involved in metabolism were the most,followed by those involved in genetic information processing.[Conclusions]The results indicated that the wood vinegar produced from apricot shell might inhibit the growth of A. fumigatus by interfering with the expression of multiple genes involved in multiple signaling pathways.展开更多
The aim of the present study was to determine the MICs using broth microdilution method and their combination effect by （minimum inhibitory concentrations） of selected antibiotic agents determination of FICindex （f...The aim of the present study was to determine the MICs using broth microdilution method and their combination effect by （minimum inhibitory concentrations） of selected antibiotic agents determination of FICindex （fractional inhibitory concentrations）. Lysozyme Anodonta cygnea was more active than Lysozyme Uniopictorum, especially against Gram-negative bacterias. Combination of Macropen and Lysozyme Unio pictorum has a synergistic effect, while a separation of these antibacterial agents was not active against some of the strains of microorganisms.展开更多
AIM:To evaluate the anti-Helicobacter pylori (H.pylori) activity of 50 traditional Chinese herbal medicines in order to provide the primary evidence for their use in clinical practice.METHODS:A susceptibility test of ...AIM:To evaluate the anti-Helicobacter pylori (H.pylori) activity of 50 traditional Chinese herbal medicines in order to provide the primary evidence for their use in clinical practice.METHODS:A susceptibility test of water extract from 50 selected traditional Chinese herbal medicines for in vitro H.pylori Sydney strain 1 was performed with broth dilution method.Anti-H.pylori activity of the selected Chinese herbal medicines was evaluated according to their minimum inhibitory concentration (MIC).RESULTS:The water extract from Rhizoma Coptidis,Radix Scutellariae and Radix isatidis could significantly inhibit the H.pylori activity with their MIC less than 7.8 mg/mL,suggesting that traditional Chinese herbal medicines have anti-inflammatory and antibacterial effects and can thus be used in treatment of H.pylori infection.CONCLUSION:Rhizoma Coptidis,Radix Scutellariae and Radix isatidis are the potential sources for the synthesis of new drugs against H.pylori.展开更多
Parent compounds of cyclopentadienyltitanium substituted heteropolytungstates with Keggin structure,An[(CpTi)XW11O39]·xH2O(A=Me4N,K;X=P,Si,Co;Cp=η5-C5H5) were synthesized in aqueous phase.By allowing parent hete...Parent compounds of cyclopentadienyltitanium substituted heteropolytungstates with Keggin structure,An[(CpTi)XW11O39]·xH2O(A=Me4N,K;X=P,Si,Co;Cp=η5-C5H5) were synthesized in aqueous phase.By allowing parent heteropoly compounds to react with protonated 8-quinolinol,the title supermolecular compounds(C9H8NO)mAn[(CpTi)XW11O39]·xH2O(A=Me4N,H;X=P,Si,Co) were synthesized.The title compounds were characterized by means of elementary analysis,IR,UV,1H NMR,XRD and TG-DSC.The results indicate that the title compounds are new heteropoly compounds,and there is a charge transfer interaction between the organic cation and heteropoly anion.The results obtained from thermal analysis show that QCpTiPW,QCpTiSiW and QCpTiCoW begin to decompose at 212.4,194.2 and 171.2 ℃,respectively.The results obtained from antibacterial test reveal that QCpTiSiW has the best antibacterial activity,and the MIC values of QCpTiSiW against Escherichia coli and Staphylococcus aurous are 64.0 and 0.500 μg·mL-1,respectively.展开更多
The nucleotide sequence deduced from the amino acid sequence of the scorpion insectotoxin AaIT was chemically synthesized and was expressed in Escherichia coli. The authenticity of this in vitro expressed peptide was ...The nucleotide sequence deduced from the amino acid sequence of the scorpion insectotoxin AaIT was chemically synthesized and was expressed in Escherichia coli. The authenticity of this in vitro expressed peptide was confirmed by N-terminal peptide sequencing. Two groups of bioassays, artificial diet incorporation assay and contact insecticidal effect assay, were carried out separately to verify the toxicity of this recombinant toxin. At the end of a 24 h experimental period, more than 60% of the testing diamondback moth (Plutella xylostella) larvae were killed in both groups with LC50 value of 18.4 microM and 0.70 microM respectively. Cytotoxicity assay using cultured Sf9 insect cells and MCF-7 human cells demonstrated that the toxin AaIT had specific toxicity against insect cells but not human cells. Only 0.13 microM recombinant toxin was needed to kill 50% of cultured insect cells while as much as 1.3 microM toxin had absolutely no effect on human cells. Insect cells produced obvious intrusions from their plasma membrane before broken up. We infer that toxin AaIT bind to a putative sodium channel in these insect cells and open the channel persistently, which would result in Na+ influx and finally cause destruction of insect cells.展开更多
Two Klebsiella pneumoniae isolates （Kpcl and Kpc2） were obtained from liver samples of seven dead chickens and identified with Vitek-32 automated identification system. Antimicrobial susceptibilities were determined...Two Klebsiella pneumoniae isolates （Kpcl and Kpc2） were obtained from liver samples of seven dead chickens and identified with Vitek-32 automated identification system. Antimicrobial susceptibilities were determined by the microdilution broth method. Detection of genes encoding class A β-lactamases was performed by PCR amplification, and cloning of the ESBL gene was by plasmid restriction and fragments ligation. Conjugation assay, transformation experiments and plasmid profile analysis were performed. The incompatibility group of ESBL-carrying plasmid was determined by the PCR-based replicon typing method. Lastly, the genetic environment was analysed by direct sequencing of the DNA surrounding the ESBL gene. The genes associated with tetracycline and gentamicin resistance were also sought by PCR. The results revealed that the ESBL phenotype-negative strain Kpc2 only showed resistance to ampicillin, amoxicillin, tetracycline, and doxycycline and carried bla TEM-1 and tet（A） genes. The ESBL-producing strain Kpcl exhibited multidrug resistant phenotype and harbored bla TEM-1 , bla CTX-M-14, tet（A）, tet（B）, and rmtB genes. K. pneumoniae Kpcl contained four plasmids with molecular sizes of approximately 59, 6.9, 2.8, and 1.6 kb, but only a 59-kb plasmid, carried bla TEM-1 and blac CTM-14 genes, was observed in its transconjugant. The incompatibility group of plasmid carrying blaCTX-M-14 gene could not be determined. The bla CTX-M-14 gene was flanked upstream by an ISEcpl insertion sequence and downstream by an IS903 element. This work shows that CTX-M-14 is present in K. pneumoniae isolates from chickens in China. The bla CTX -M-4 gene was associated with an upstream ISEcpl insertion sequence. Our results underline the need for continuous surveillance of the prevalence and evolution of this CTX-M-type β-lactamase in China.展开更多
A series of 1,4-dihydro-1,3,5-triazine derivatives were designed and synthesized and their antibacterial and antifungal activities were evaluated. Most of the synthesized compounds showed potent inhibition of several ...A series of 1,4-dihydro-1,3,5-triazine derivatives were designed and synthesized and their antibacterial and antifungal activities were evaluated. Most of the synthesized compounds showed potent inhibition of several Gram-positive bacterial strains（including multidrug-resistant clinical isolates） and Gramnegative bacterial strains, with minimum inhibitory concentrations（MICs） in the range of 2.1–181.2 mmol/L. Compounds 7a and 7c presented the most potent inhibitory activities against Grampositive bacteria（e.g., Staphylococcus aureus 4220）, Gram-negative bacteria（e.g., Escherichia coli 1924）,and the fungus Candida albicans 7535, with MICs of 2.1 or 4.1 mmol/L. Especially, compound 7a was the most potent, with an MIC of 2.1 mmol/L against four multidrug-resistant, Gram-positive bacterial strains.The cytotoxic activity of the compound 7a, 7c and 7f was assessed in HepG2 cells, and the results suggest that 1,4-dihydro-1,3,5-triazine derivatives bearing a 6-benzyloxynaphthalen moiety are interesting scaffolds for the development of novel antibacterial agents.展开更多
Aqueous extracts from various plant parts of fenugreek(3%)(aerial parts:leaves and stems(LS),roots(R),ground seeds(GS)and not ground seeds(NGS))and petroleum ether,ethyl acetate and methanolic fractions of the aerial ...Aqueous extracts from various plant parts of fenugreek(3%)(aerial parts:leaves and stems(LS),roots(R),ground seeds(GS)and not ground seeds(NGS))and petroleum ether,ethyl acetate and methanolic fractions of the aerial parts were assayed to determine their antifungal potential against Botrytis cinerea,Fusarium graminearum,Alternaria sp.,Pythium aphanidermatum,and Rhizoctinia solani.All fenugreek plant parts showed antifungal potential and the magnitude of their inhibitory effects was species and plant parts d...展开更多
Objective：To explore the antibacterial effect of Chinese crude drugs against clinical strains of Ureaplasma urealyticum（UU）, including eight pure herbs and three compound herbs, and determine their minimal inhibito...Objective：To explore the antibacterial effect of Chinese crude drugs against clinical strains of Ureaplasma urealyticum（UU）, including eight pure herbs and three compound herbs, and determine their minimal inhibitory concentrations（MICs）. Methods：Isolates were collected from clinical patients with UU infection, and cultured in UU broth. In order to test the different effects on clinical strains of UU, the assays were performed by microdilution inhibition tests, and MICs of the herbs against the clinical strains of UU were calculated. Results：The MICs of eight pure herbs against clinical strains of UU were as follows： Galla Chinensis：0.313-1.25 g/L; Fructus Forsythiae： 1.25-5.00 g/L; Cortex Phellodendri： 1.25-5.00 g/L; Radix Paeoniae Rubra： 1.25-2.50 g/L; Semen Plantaginis：2.50-10.00 g/L; Herba Lysimachiae： 5.00-20.00 g/L; Rhizoma Coptidis： 5.00-20.00g/L, Herba Houttuyniae： 10.00-20.00 g/L. The MICs of compound herbs were： Liuheji： 0.625-2.50 g/L; Bazhengsan： 5.00-20.00 g/L; Wulinsan：2.50-20.0 g/L.Conclusion：Galla Chinensis, Fructus Forsythiae, Cortex Phellodendrim, Radix Paeoniae Rubra, and Semen Plantaginis, exerted the stronger antibacterial effect against clinical strains of UU, whereas Herba Lysimachiae, Rhizoma Coptidis and Herba Houttuyniae, had relatively weaker activity against UU. Compound herbs, Bazhengsan and Wulinsan, and particularly Liuheji, also had antibacterial effects against UU. Further studies of the effects and mechanisms of action of Chinese crude drugs against UU infections are worthwhile.展开更多
Mycoplasma synoviae(M.synoviae)infections have become an increasingly serious concern in China because they cause huge economic losses to the poultry industry.Antibiotic treatment is one of control strategies that can...Mycoplasma synoviae(M.synoviae)infections have become an increasingly serious concern in China because they cause huge economic losses to the poultry industry.Antibiotic treatment is one of control strategies that can be used to contain clinical outbreaks in M.synoviae-free flocks,especially because the bacteria can be transmitted through eggs.To understand M.synoviae infection status in farms of central China and the antibiotic susceptibility of the circulating strains in vivo and in vitro,485 samples were collected from five provinces from 2019 to 2021.Fifty-two strains were isolated and identified.Determination of the minimum inhibitory concentration(MIC)of eight antibiotics(tylvalosin,tiamulin,tilmicosin,lincomycin,enrofloxacin,chlortetracycline,doxycycline and tylosin)for isolates showed that tylvalosin,doxycycline and tiamulin were effective against 52 clinical isolates(MIC values≤0.0625-0.25μg/mL,≤0.0625-1μg/mL,and 0.25-2μg/mL,respectively).Tilmicosin,enrofloxacin and lincomycin had high MICo values(>32μg/mL).An artificial M.synoviae infection model was established in chickens for evaluation of the short-term therapeutic effect of these antibiotics.After 5 days of medication,doxycycline(200 mg/L)showed a superior ability to inhibit M.synoviae compared with other groups,as did tylvalosin(200 mg/L).Furthermore,the therapeutic efficacy of tylvalosin(0.4μg/mL)on intra-embryo-injected M.synoviae was higher than that of tiamulin at the same dose.A combination of MiC values determined in vitro and therapeutic effects observed in vivo revealed that tylvalosin and doxycycline had the best therapeutic effects.Tylvalosin also showed better inhibitory effects on the vertical transmis-sion of M.synoviae than tiamulin.展开更多
AIM： To evaluate the antimicrobial potential of Terminalia chebula （ T. chebula） extracts against pathogens causing otitis externa and compare it with ear drops.METHODS： Four different extracts, methanol, ethanol...AIM： To evaluate the antimicrobial potential of Terminalia chebula （ T. chebula） extracts against pathogens causing otitis externa and compare it with ear drops.METHODS： Four different extracts, methanol, ethanol, acetone and aqueous （hot and cold） extracts, from the T. chebula were tested for their antimicrobial activity through the agar well diffusion method and minimum inhibitory concentration （MIC）/minimum bactericidal concentration （MBC） values were determined through the macrodilution broth method against six different microorganism, five bacterial （one gram positive and four gram negative） and one yeast.RESULTS： Organic and aqueous fruit extracts displayed activity against all fve tested bacterial ear pathogens with a maximum zone of inhibition of 31.6 mm against Staphylococcus aureus , followed by Acinetobacter sp. （24.6 mm）, Pseudomonas aeruginosa （23.6 mm）, Proteus mirabilis （21 mm） and Escherichia coli （19.3mm）. Of the four solvents evaluated, acetonic fruit extract of T. chebula was found to be best. The MIC values ranged between 0.78 mg/mL and 50 mg/mL for the different bacterial ear pathogens and MBC values ranged between 1.56 mg/mL and 50 mg/mL. The acetonic fruit extract showed larger inhibition zones compared to the herbal ear drops, Kan pip with lowest MIC of 0.78 mg/mL and MBC of 1.56 mg/mL.CONCLUSION： Acetonic extract of T. chebula fruit may be used to treat otitis externa. However, more detailed studies, such as in vivo testing and pharmacokinetics properties, are needed to determine its therapeutic potential.展开更多
[Objective]This study aimed to observe the antibacterial activity of Berberis julianae Schneid and Cinnamomum camphora（ L.） Presl. aqueous extracts and their antibiotical effect when being used with commonly used an...[Objective]This study aimed to observe the antibacterial activity of Berberis julianae Schneid and Cinnamomum camphora（ L.） Presl. aqueous extracts and their antibiotical effect when being used with commonly used antibiotics in- vitro. [Method] Broth microdilution method and checkerboard dilution method were used and the reference strain E. coli ATCC25922 and clinical sample separation strains of E. coli and Salmonella were selected to determine the minimum inhibitory concentration（ MIC） and fractional inhibitory concentration（ FIC）. [Result] The MICs of Berberis julianae Schneid and Cinnamomum camphora（ L.） Presl. for E. coli and Salmonella were both 1 mg /mL,and that of other antibiotics for the two strains were in the quality control range provided by NCCLS. [Conclusion] The synergistic effect or additive effect were observed when they were applied with the commonly used antibiotics.展开更多
A series of bis-quaternary ammonium compounds（bis-QACs） N,N＇-hevamethylenebis（1-alkyl-4-carbamoyl pyridinium bromide）（4BCAP-6,n）（alkyl chain length,n=8,10,12,14,16 and 18） were synthesized and characterized.T...A series of bis-quaternary ammonium compounds（bis-QACs） N,N＇-hevamethylenebis（1-alkyl-4-carbamoyl pyridinium bromide）（4BCAP-6,n）（alkyl chain length,n=8,10,12,14,16 and 18） were synthesized and characterized.Their surface tensions,critical micelle concentrations（CMC）,and antimicrobial activities were evaluated.4BCAP-6,10 exhibited the strongest antimicrobial activities except for that against Proteus vulgari.The activities of 4BCAP-6.n against Escherichia coli zk126 were not significantly influenced by temperature.pH and initial bacteria concentration.These results indicate that bis-QACs exhibit high antimicrobial activity regardless of the environmental conditions.展开更多
This study aimed to explore the anti-bacterial and anti-fungal activities of extracts from different parts of plants in the Zingiberaceae family.The inhibitory rate,minimum inhibitory concentration(MIC),and minimum ba...This study aimed to explore the anti-bacterial and anti-fungal activities of extracts from different parts of plants in the Zingiberaceae family.The inhibitory rate,minimum inhibitory concentration(MIC),and minimum bactericidal concentration(MBC)of leaf and stem,and root and rhizome extracts from Alpinia katsumadai Hayata,Alpinia oxyphylla Miq×Alpinia henryi K.Schumann,Alpinia oblongifolia Hayata,Alpinia nigra(Gaertn.)Burtt,Amomum villosum Lour,Alpinia zerumbet(Pers.)Burtt.et Smith and Alpinia oxyphylla Miq were determined using the fungus cake method and double dilution method.The seven Zingiberaceae plants exhibited characteristic antibacterial activities against pathogenic bacteria and fungi.At a 1.5 mg mL^(−1),A.zerumbet root and rhizome extracts exhibited strong inhibitory activity against S.aureus and E.coli,with 83.23%and 79.62%,respectively.In addition,A.zerumbet leaf and stem extracts had an inhibitory rate of 90.85%against P.aeruginosa.At the same concentration,the leaf and stem,root and rhizome extracts of A.katsumadai had the best anti-bacterial effect against F.oxysporum,with inhibition rates of 84.46%and 84.73%,respectively.Moreover,A.katsumadai and A.zerumbet leaf and stem extracts had the most significant antibacterial effect against S.aureus,with a MIC of 0.063 mg mL^(−1).Thus,both A.katsumadai and A.zerumbet extracts had significant antibacterial activity.In addition,by comparing the inhibitory effect of extracts from different parts,it was found that the inhibitory rate and average inhibitory rate of extracts from leaf and stem were higher than those from root and rhizome.The chemical constituents of A.katsumadai and A.zerumbet,determined by the high-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS),revealed that citric acid(CA),alpinetin,and pinocembrin(PNCB)were the functional constituents yielding the antibacterial activity.Overall,A.katsumadai and A.zerumbet have the potential to be developed as new plant fungicides and bactericides.展开更多
Three benzopyranocoumarins（OBH, OMH and ODH） were synthesized and characterized via IR, ^1H NMR and HRMS. The HB energy in OBH, OMH and ODH was performed with the density functional theory（DFT） [B3LYP/6-31G＊] met...Three benzopyranocoumarins（OBH, OMH and ODH） were synthesized and characterized via IR, ^1H NMR and HRMS. The HB energy in OBH, OMH and ODH was performed with the density functional theory（DFT） [B3LYP/6-31G＊] method. The in vitro antibacterial activity of OBH, OMH and ODH against drug-sensitive S. aureus（S. aureus ATCC 29213） strain, MRSA strain（MRSA XJ 75302）, drug-sensitive S. epidermidis strain（S. epidermidis ATCC 14990） and methicillin-resistant S. epidermidis strain（MRSE XJ 75284） was evaluated by observing the minimum inhibitory concentration. The results showed that among the three compounds, ODH exhibited the most potent antibacterial activity.展开更多
The tomato(Solanum lycopersicum L.)is one of the world’s most important vegetable crops.Still,phytopathogenic bacteria affect the yield and quality of tomato cultivation,like Agrobacterium tumefeciens(At),Clavibacter...The tomato(Solanum lycopersicum L.)is one of the world’s most important vegetable crops.Still,phytopathogenic bacteria affect the yield and quality of tomato cultivation,like Agrobacterium tumefeciens(At),Clavibacter michiganensis subsp.michiganensis(Cmm),Pseudomonas syringae pv.tomato(Pst),Ralstonia solanacearum(Rs),and Xanthomonas axonopodis(Xa).Synthetic chemical products are used mostly on disease plant control,but overuse generates resistance to bacterial control.This study aimed to evaluate the in vitro antibacterial activity of the ethanolic extract of Moringa oleifera Lam.leaves against At,Cmm,Pst,Rs,and Xa,as well as information about this plant species’chemical composition.Antibacterial activity against pathogens observed by microplate technique,phytochemical screening,and FTIR analysis revealed different bio-active compounds on ethanolic extracts with antibacterial activity.The growth inhibition rate ranged between 0.08%and 99.94%.The inhibitory concentration,IC50,required to inhibit 50%of At,Cmm,Pst,Rs,and Xa bacterial growth,was 276.67,350.48,277.85,351.49,and 283.22 mg/L,respectively.Inhibition of phytopathogen bacteria’s growth increased as the concentrations of the extract also increased.Moringa oleifera extract can be recommended as a potent bio-bactericide.展开更多
Multiple drug resistant(MDR)and methicillin-resistant Staphylococcus aureus(MRSA)have become increasingly prevalent as a community acquired infection.As a result limited treatment options are available with convention...Multiple drug resistant(MDR)and methicillin-resistant Staphylococcus aureus(MRSA)have become increasingly prevalent as a community acquired infection.As a result limited treatment options are available with conventional synthetic antibiotics.Bioprospecting natural products with potent antimicrobial activity show promise for developing new drugs against this pathogen.In this study,we have investigated the antimicrobial activity of a purple violet pigment(PVP)from an Antarctic bacterium,Janthinobacterium sp.Ant5-2 on 15 clinical MDR and MRSA strains.The colorimetric resazurin assay was employed to determine the minimum inhibitory concentration(MIC90)of PVP against MDR and MRSA.The MIC90 ranged between 1.57μg/mL and 3.13μg/mL,which are significantly lower than many antimicrobials tested from natural sources against this pathogen.The spectrophotometrically determined growth analysis and total microscopic counts using Live/dead®BacLight™fluorescent stain exhibited a steady decrease in viability of both MDR and MRSA cultures following treatment with PVP at the MIC levels.In silico predictive molecular docking study revealed that PVP could be a DNA-targeting minor groove binding antimicrobial compound.The continued development of novel antimicrobials derived from natural sources with the combination of a suite of conventional antibiotics could stem the rising pandemic of MDR and MRSA along with other deadly microbial pathogens.展开更多
The antibacterial activity of methanol and acetone extracts of five plant extracts being utilized for the cure of different ailments in Pakistan was studied.The extracts of Curcuma zedoaria,Ipomea turpethum,Sphaeranth...The antibacterial activity of methanol and acetone extracts of five plant extracts being utilized for the cure of different ailments in Pakistan was studied.The extracts of Curcuma zedoaria,Ipomea turpethum,Sphaeranthus indicus,Terminalia chebula and Tricholepis glaberrima were tested against seven different bacterial strains by well diffusion method and microdilution methods.The pattern of zone of inhibition varied with the plant extracts,the solvent used for extraction and organisms tested.Plant extracts(20 mg/mL) were used to evaluate antibacterial activities.The zone of inhibition exhibited by methanol extracts varied between 11 mm and 32 mm while those of acetone extracts varied between 9 mm and 25 mm respectively.The minimum inhibitory concentration(MIC) exhibited by methanol extracts ranged between(18.4-51.1) mg/mL.Overall methanolic extracts showed more activity than the acetone extracts against tested organisms except for S.indicus.The plants were also analyzed for their elemental composition using atomic absorption spectrophotometer to explore natural sources of essential elements that can be utilized for medicinal purposes.展开更多
The purpose of this study was to first evaluate the antimicrobial effects of powder and extracts of berries (rose-hip, aronia, sea buckthorn and hawthorn) on the development of antibiotic-resistant <i><span s...The purpose of this study was to first evaluate the antimicrobial effects of powder and extracts of berries (rose-hip, aronia, sea buckthorn and hawthorn) on the development of antibiotic-resistant <i><span style="font-family:Verdana;">L</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">monocitogenes</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">Listeria</span></i> <i><span style="font-family:Verdana;">monocytogenes</span></i><span style="font-family:Verdana;"> is considered one of the most important pathogens responsible for food-borne infection. Antimicrobial properties were evaluated using the standard Kirby-Bauer disk diffusion method. Bacterial inactivation networks were determined and compared, as well as the possibility of using powders and extracts of berries to control the risk of </span><i><span style="font-family:Verdana;">Listeria</span></i> <i><span style="font-family:Verdana;">monocytogees</span></i><span style="font-family:Verdana;"> infestation in the milk and dairy industry as well as in the meat industry. The effect of pH (4.78 - 4.43) and water activity (0.90 - 0.80) on the relationship between optical density (OD) at 600 nm and the plate count (CFU ml<sup>-</sup></span><span style="font-family:Verdana;"><sup>1</sup></span><span style="font-family:Verdana;">) was investigated for </span><i><span style="font-family:Verdana;">Listeria</span></i> <i><span style="font-family:Verdana;">monocytogenes</span></i><span style="font-family:Verdana;">. It was determined Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) </span><span style="font-family:Verdana;">of berries for</span><span style="font-family:;" "=""> </span><i><span style="font-family:Verdana;">L. monocytogenes</span></i><span style="font-family:Verdana;">. </span><span style="font-family:Verdana;">The most relevant bacteriostatic and bactericidal </span><span style="font-family:;" "=""><span style="font-family:Verdana;">effect on </span><i><span style="font-family:Verdana;">L. monocytogenes</span></i><span style="font-family:Verdana;"> in the tested berries demonstrated sea buckthorn and rosehip.</span></span>展开更多
基金Supported by The National Natural Science Foundation of China, No. 30470777
文摘AIM： To investigate the increasing the susceptibility pylon） to metronidazole. mechanisms of aspirin of Helicobacter pylori （H METHODS： Hpylori reference strain 26695 and two metronidazole-resistant isolates of H pylori were included in this study. Strains were incubated in Brucella broth with or without aspirin （1 mmol/L）. The rdxA gene of Hpylori was amplified by PCR and sequenced. The permeability of Hpylori to antimicrobials was determined by analyzing the endocellular radioactivity of the cells after incubated with [7-^3H]-tetracycline. The outer membrane proteins （OMPs） of Hpylori 26695 were depurated and analyzed by SDS-PAGE. The expression of 5 porins （hopA, hopB, hopC, hopD and hopE） and the putative RND efflux system （hefABC） of H pylori were analyzed using real-time quantitative PCR. RESULTS： The mutations in rdxA gene did not change in metronidazole resistant isolates treated with aspirin. The radioactivity of H pylori increased when treated with aspirin, indicating that aspirin improved the permeability of the outer membrane of H pylori. However, the expression of two OMP bands between 55 kDa and 72 kDa altered in the presence of aspirin.The expression of the mRNA of hopA, hopB, hopC, hopD, hopE and herA, hefB, hefC of H pylori did not change when treated with aspirin. CONCLUSION： Although aspirin increases the susceptibility of H pylori to metronidazole, it has no effect on the mutations of rdxA gene of Hpylori. Aspirin increases endocellular concentrations of antimicrobials probably by altering the OMP expression.
基金Supported by the Key Scientific and Technological Research Project for Universities of Hebei Province(ZD2018306)
文摘[Objectives] This study was conducted to explore the antifungal activity of wood vinegar produced from apricot shell. [Methods]The minimal inhibitory concentration（ MIC） of wood vinegar against Aspergillus fumigatus was determined on agar plates. Then,the mycelial growth and the morphology of the apical vesicles of A. fumigatus cultured in the medium supplemented with 1/2 MIC wood vinegar were observed to evaluate the effect of wood vinegar on A. fumigatus.RNA-Seq was performed to explore the antifungal mechanism of wood vinegar. [Results] The wood vinegar produced from apricot shell could inhibit the growth of A. fumigatus,with a MIC of 20 μl/ml. In the medium supplemented with 1/2 MIC wood vinegar,the mycelial growth of A. fumigatus was suppressed,some apical vesicles were incompletely developed. The gene ontology（ GO） term enrichment analysis based on RNA-Seq showed that the differentially expressed genes（ DEGs）were enriched in metabolic process,cellular process and single-organism process in the category of biological processes,cell,cell part,membrane,organelle and membrane part in the category of cellular components,catalytic activity and binding in the category of molecular function. The significantly up-regulated DEGs were mostly involved in cell,cell part,organelle,organelle part and macro molecular complex in the category of cellular component,while the significantly down-regulated DEGs were mostly involved in biological process,cellular process and single-organism process in the category of biological process,catalytic activity,binding,transporter activity,and nucleic acid binding transcription factor activity in the category molecular function. Moreover,KEGG（ Kyoto Encyclopedia of Genes and Genomes） pathway analysis showed that the DEG unigenes involved in metabolism were the most,followed by those involved in genetic information processing.[Conclusions]The results indicated that the wood vinegar produced from apricot shell might inhibit the growth of A. fumigatus by interfering with the expression of multiple genes involved in multiple signaling pathways.
文摘The aim of the present study was to determine the MICs using broth microdilution method and their combination effect by （minimum inhibitory concentrations） of selected antibiotic agents determination of FICindex （fractional inhibitory concentrations）. Lysozyme Anodonta cygnea was more active than Lysozyme Uniopictorum, especially against Gram-negative bacterias. Combination of Macropen and Lysozyme Unio pictorum has a synergistic effect, while a separation of these antibacterial agents was not active against some of the strains of microorganisms.
基金Supported by The Cooperation Project in Industry,Education and Research of Guangdong Province and Ministry of Education of China,No.2009B090300280
文摘AIM:To evaluate the anti-Helicobacter pylori (H.pylori) activity of 50 traditional Chinese herbal medicines in order to provide the primary evidence for their use in clinical practice.METHODS:A susceptibility test of water extract from 50 selected traditional Chinese herbal medicines for in vitro H.pylori Sydney strain 1 was performed with broth dilution method.Anti-H.pylori activity of the selected Chinese herbal medicines was evaluated according to their minimum inhibitory concentration (MIC).RESULTS:The water extract from Rhizoma Coptidis,Radix Scutellariae and Radix isatidis could significantly inhibit the H.pylori activity with their MIC less than 7.8 mg/mL,suggesting that traditional Chinese herbal medicines have anti-inflammatory and antibacterial effects and can thus be used in treatment of H.pylori infection.CONCLUSION:Rhizoma Coptidis,Radix Scutellariae and Radix isatidis are the potential sources for the synthesis of new drugs against H.pylori.
基金supported by the chemical materials institute China academy of engineering physics,the doctoral innovation research assistance program of science and technology review
文摘Parent compounds of cyclopentadienyltitanium substituted heteropolytungstates with Keggin structure,An[(CpTi)XW11O39]·xH2O(A=Me4N,K;X=P,Si,Co;Cp=η5-C5H5) were synthesized in aqueous phase.By allowing parent heteropoly compounds to react with protonated 8-quinolinol,the title supermolecular compounds(C9H8NO)mAn[(CpTi)XW11O39]·xH2O(A=Me4N,H;X=P,Si,Co) were synthesized.The title compounds were characterized by means of elementary analysis,IR,UV,1H NMR,XRD and TG-DSC.The results indicate that the title compounds are new heteropoly compounds,and there is a charge transfer interaction between the organic cation and heteropoly anion.The results obtained from thermal analysis show that QCpTiPW,QCpTiSiW and QCpTiCoW begin to decompose at 212.4,194.2 and 171.2 ℃,respectively.The results obtained from antibacterial test reveal that QCpTiSiW has the best antibacterial activity,and the MIC values of QCpTiSiW against Escherichia coli and Staphylococcus aurous are 64.0 and 0.500 μg·mL-1,respectively.
基金This work was supported by a grant from 863High Technology Program,Chinese Ministry of Sci-ence and Technology
文摘The nucleotide sequence deduced from the amino acid sequence of the scorpion insectotoxin AaIT was chemically synthesized and was expressed in Escherichia coli. The authenticity of this in vitro expressed peptide was confirmed by N-terminal peptide sequencing. Two groups of bioassays, artificial diet incorporation assay and contact insecticidal effect assay, were carried out separately to verify the toxicity of this recombinant toxin. At the end of a 24 h experimental period, more than 60% of the testing diamondback moth (Plutella xylostella) larvae were killed in both groups with LC50 value of 18.4 microM and 0.70 microM respectively. Cytotoxicity assay using cultured Sf9 insect cells and MCF-7 human cells demonstrated that the toxin AaIT had specific toxicity against insect cells but not human cells. Only 0.13 microM recombinant toxin was needed to kill 50% of cultured insect cells while as much as 1.3 microM toxin had absolutely no effect on human cells. Insect cells produced obvious intrusions from their plasma membrane before broken up. We infer that toxin AaIT bind to a putative sodium channel in these insect cells and open the channel persistently, which would result in Na+ influx and finally cause destruction of insect cells.
基金funded by the National Natural Science Foundation of China (31072170)
文摘Two Klebsiella pneumoniae isolates （Kpcl and Kpc2） were obtained from liver samples of seven dead chickens and identified with Vitek-32 automated identification system. Antimicrobial susceptibilities were determined by the microdilution broth method. Detection of genes encoding class A β-lactamases was performed by PCR amplification, and cloning of the ESBL gene was by plasmid restriction and fragments ligation. Conjugation assay, transformation experiments and plasmid profile analysis were performed. The incompatibility group of ESBL-carrying plasmid was determined by the PCR-based replicon typing method. Lastly, the genetic environment was analysed by direct sequencing of the DNA surrounding the ESBL gene. The genes associated with tetracycline and gentamicin resistance were also sought by PCR. The results revealed that the ESBL phenotype-negative strain Kpc2 only showed resistance to ampicillin, amoxicillin, tetracycline, and doxycycline and carried bla TEM-1 and tet（A） genes. The ESBL-producing strain Kpcl exhibited multidrug resistant phenotype and harbored bla TEM-1 , bla CTX-M-14, tet（A）, tet（B）, and rmtB genes. K. pneumoniae Kpcl contained four plasmids with molecular sizes of approximately 59, 6.9, 2.8, and 1.6 kb, but only a 59-kb plasmid, carried bla TEM-1 and blac CTM-14 genes, was observed in its transconjugant. The incompatibility group of plasmid carrying blaCTX-M-14 gene could not be determined. The bla CTX-M-14 gene was flanked upstream by an ISEcpl insertion sequence and downstream by an IS903 element. This work shows that CTX-M-14 is present in K. pneumoniae isolates from chickens in China. The bla CTX -M-4 gene was associated with an upstream ISEcpl insertion sequence. Our results underline the need for continuous surveillance of the prevalence and evolution of this CTX-M-type β-lactamase in China.
基金supported by the National Natural Science Foundation of China(Nos.81260468,81460524 and 81060257)the Natural Science Foundation of Jilin Province(No.20160101218JC)
文摘A series of 1,4-dihydro-1,3,5-triazine derivatives were designed and synthesized and their antibacterial and antifungal activities were evaluated. Most of the synthesized compounds showed potent inhibition of several Gram-positive bacterial strains（including multidrug-resistant clinical isolates） and Gramnegative bacterial strains, with minimum inhibitory concentrations（MICs） in the range of 2.1–181.2 mmol/L. Compounds 7a and 7c presented the most potent inhibitory activities against Grampositive bacteria（e.g., Staphylococcus aureus 4220）, Gram-negative bacteria（e.g., Escherichia coli 1924）,and the fungus Candida albicans 7535, with MICs of 2.1 or 4.1 mmol/L. Especially, compound 7a was the most potent, with an MIC of 2.1 mmol/L against four multidrug-resistant, Gram-positive bacterial strains.The cytotoxic activity of the compound 7a, 7c and 7f was assessed in HepG2 cells, and the results suggest that 1,4-dihydro-1,3,5-triazine derivatives bearing a 6-benzyloxynaphthalen moiety are interesting scaffolds for the development of novel antibacterial agents.
文摘Aqueous extracts from various plant parts of fenugreek(3%)(aerial parts:leaves and stems(LS),roots(R),ground seeds(GS)and not ground seeds(NGS))and petroleum ether,ethyl acetate and methanolic fractions of the aerial parts were assayed to determine their antifungal potential against Botrytis cinerea,Fusarium graminearum,Alternaria sp.,Pythium aphanidermatum,and Rhizoctinia solani.All fenugreek plant parts showed antifungal potential and the magnitude of their inhibitory effects was species and plant parts d...
文摘Objective：To explore the antibacterial effect of Chinese crude drugs against clinical strains of Ureaplasma urealyticum（UU）, including eight pure herbs and three compound herbs, and determine their minimal inhibitory concentrations（MICs）. Methods：Isolates were collected from clinical patients with UU infection, and cultured in UU broth. In order to test the different effects on clinical strains of UU, the assays were performed by microdilution inhibition tests, and MICs of the herbs against the clinical strains of UU were calculated. Results：The MICs of eight pure herbs against clinical strains of UU were as follows： Galla Chinensis：0.313-1.25 g/L; Fructus Forsythiae： 1.25-5.00 g/L; Cortex Phellodendri： 1.25-5.00 g/L; Radix Paeoniae Rubra： 1.25-2.50 g/L; Semen Plantaginis：2.50-10.00 g/L; Herba Lysimachiae： 5.00-20.00 g/L; Rhizoma Coptidis： 5.00-20.00g/L, Herba Houttuyniae： 10.00-20.00 g/L. The MICs of compound herbs were： Liuheji： 0.625-2.50 g/L; Bazhengsan： 5.00-20.00 g/L; Wulinsan：2.50-20.0 g/L.Conclusion：Galla Chinensis, Fructus Forsythiae, Cortex Phellodendrim, Radix Paeoniae Rubra, and Semen Plantaginis, exerted the stronger antibacterial effect against clinical strains of UU, whereas Herba Lysimachiae, Rhizoma Coptidis and Herba Houttuyniae, had relatively weaker activity against UU. Compound herbs, Bazhengsan and Wulinsan, and particularly Liuheji, also had antibacterial effects against UU. Further studies of the effects and mechanisms of action of Chinese crude drugs against UU infections are worthwhile.
基金This work was supported by the Key Research and Development Project of Hubei Province(Grant No.2021BBA252)the Earmarked Fund for China Agriculture Research System(CARS-41).
文摘Mycoplasma synoviae(M.synoviae)infections have become an increasingly serious concern in China because they cause huge economic losses to the poultry industry.Antibiotic treatment is one of control strategies that can be used to contain clinical outbreaks in M.synoviae-free flocks,especially because the bacteria can be transmitted through eggs.To understand M.synoviae infection status in farms of central China and the antibiotic susceptibility of the circulating strains in vivo and in vitro,485 samples were collected from five provinces from 2019 to 2021.Fifty-two strains were isolated and identified.Determination of the minimum inhibitory concentration(MIC)of eight antibiotics(tylvalosin,tiamulin,tilmicosin,lincomycin,enrofloxacin,chlortetracycline,doxycycline and tylosin)for isolates showed that tylvalosin,doxycycline and tiamulin were effective against 52 clinical isolates(MIC values≤0.0625-0.25μg/mL,≤0.0625-1μg/mL,and 0.25-2μg/mL,respectively).Tilmicosin,enrofloxacin and lincomycin had high MICo values(>32μg/mL).An artificial M.synoviae infection model was established in chickens for evaluation of the short-term therapeutic effect of these antibiotics.After 5 days of medication,doxycycline(200 mg/L)showed a superior ability to inhibit M.synoviae compared with other groups,as did tylvalosin(200 mg/L).Furthermore,the therapeutic efficacy of tylvalosin(0.4μg/mL)on intra-embryo-injected M.synoviae was higher than that of tiamulin at the same dose.A combination of MiC values determined in vitro and therapeutic effects observed in vivo revealed that tylvalosin and doxycycline had the best therapeutic effects.Tylvalosin also showed better inhibitory effects on the vertical transmis-sion of M.synoviae than tiamulin.
基金Supported by Kurukshetra University,Kurukshetra,Haryana
文摘AIM： To evaluate the antimicrobial potential of Terminalia chebula （ T. chebula） extracts against pathogens causing otitis externa and compare it with ear drops.METHODS： Four different extracts, methanol, ethanol, acetone and aqueous （hot and cold） extracts, from the T. chebula were tested for their antimicrobial activity through the agar well diffusion method and minimum inhibitory concentration （MIC）/minimum bactericidal concentration （MBC） values were determined through the macrodilution broth method against six different microorganism, five bacterial （one gram positive and four gram negative） and one yeast.RESULTS： Organic and aqueous fruit extracts displayed activity against all fve tested bacterial ear pathogens with a maximum zone of inhibition of 31.6 mm against Staphylococcus aureus , followed by Acinetobacter sp. （24.6 mm）, Pseudomonas aeruginosa （23.6 mm）, Proteus mirabilis （21 mm） and Escherichia coli （19.3mm）. Of the four solvents evaluated, acetonic fruit extract of T. chebula was found to be best. The MIC values ranged between 0.78 mg/mL and 50 mg/mL for the different bacterial ear pathogens and MBC values ranged between 1.56 mg/mL and 50 mg/mL. The acetonic fruit extract showed larger inhibition zones compared to the herbal ear drops, Kan pip with lowest MIC of 0.78 mg/mL and MBC of 1.56 mg/mL.CONCLUSION： Acetonic extract of T. chebula fruit may be used to treat otitis externa. However, more detailed studies, such as in vivo testing and pharmacokinetics properties, are needed to determine its therapeutic potential.
基金Funded by the Student Innovation Project of Southwest University for Nationalities in 2012(201210656017)
文摘[Objective]This study aimed to observe the antibacterial activity of Berberis julianae Schneid and Cinnamomum camphora（ L.） Presl. aqueous extracts and their antibiotical effect when being used with commonly used antibiotics in- vitro. [Method] Broth microdilution method and checkerboard dilution method were used and the reference strain E. coli ATCC25922 and clinical sample separation strains of E. coli and Salmonella were selected to determine the minimum inhibitory concentration（ MIC） and fractional inhibitory concentration（ FIC）. [Result] The MICs of Berberis julianae Schneid and Cinnamomum camphora（ L.） Presl. for E. coli and Salmonella were both 1 mg /mL,and that of other antibiotics for the two strains were in the quality control range provided by NCCLS. [Conclusion] The synergistic effect or additive effect were observed when they were applied with the commonly used antibiotics.
基金supported by the National Natural Science Foundation of China(No.20972120)Doctor Fund of Henan University of Technology(No.150392)
文摘A series of bis-quaternary ammonium compounds（bis-QACs） N,N＇-hevamethylenebis（1-alkyl-4-carbamoyl pyridinium bromide）（4BCAP-6,n）（alkyl chain length,n=8,10,12,14,16 and 18） were synthesized and characterized.Their surface tensions,critical micelle concentrations（CMC）,and antimicrobial activities were evaluated.4BCAP-6,10 exhibited the strongest antimicrobial activities except for that against Proteus vulgari.The activities of 4BCAP-6.n against Escherichia coli zk126 were not significantly influenced by temperature.pH and initial bacteria concentration.These results indicate that bis-QACs exhibit high antimicrobial activity regardless of the environmental conditions.
基金funded by the Forestry Science and Technology Innovation Project of Guangdong Province,China(2020KJCX010).
文摘This study aimed to explore the anti-bacterial and anti-fungal activities of extracts from different parts of plants in the Zingiberaceae family.The inhibitory rate,minimum inhibitory concentration(MIC),and minimum bactericidal concentration(MBC)of leaf and stem,and root and rhizome extracts from Alpinia katsumadai Hayata,Alpinia oxyphylla Miq×Alpinia henryi K.Schumann,Alpinia oblongifolia Hayata,Alpinia nigra(Gaertn.)Burtt,Amomum villosum Lour,Alpinia zerumbet(Pers.)Burtt.et Smith and Alpinia oxyphylla Miq were determined using the fungus cake method and double dilution method.The seven Zingiberaceae plants exhibited characteristic antibacterial activities against pathogenic bacteria and fungi.At a 1.5 mg mL^(−1),A.zerumbet root and rhizome extracts exhibited strong inhibitory activity against S.aureus and E.coli,with 83.23%and 79.62%,respectively.In addition,A.zerumbet leaf and stem extracts had an inhibitory rate of 90.85%against P.aeruginosa.At the same concentration,the leaf and stem,root and rhizome extracts of A.katsumadai had the best anti-bacterial effect against F.oxysporum,with inhibition rates of 84.46%and 84.73%,respectively.Moreover,A.katsumadai and A.zerumbet leaf and stem extracts had the most significant antibacterial effect against S.aureus,with a MIC of 0.063 mg mL^(−1).Thus,both A.katsumadai and A.zerumbet extracts had significant antibacterial activity.In addition,by comparing the inhibitory effect of extracts from different parts,it was found that the inhibitory rate and average inhibitory rate of extracts from leaf and stem were higher than those from root and rhizome.The chemical constituents of A.katsumadai and A.zerumbet,determined by the high-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS),revealed that citric acid(CA),alpinetin,and pinocembrin(PNCB)were the functional constituents yielding the antibacterial activity.Overall,A.katsumadai and A.zerumbet have the potential to be developed as new plant fungicides and bactericides.
文摘Three benzopyranocoumarins（OBH, OMH and ODH） were synthesized and characterized via IR, ^1H NMR and HRMS. The HB energy in OBH, OMH and ODH was performed with the density functional theory（DFT） [B3LYP/6-31G＊] method. The in vitro antibacterial activity of OBH, OMH and ODH against drug-sensitive S. aureus（S. aureus ATCC 29213） strain, MRSA strain（MRSA XJ 75302）, drug-sensitive S. epidermidis strain（S. epidermidis ATCC 14990） and methicillin-resistant S. epidermidis strain（MRSE XJ 75284） was evaluated by observing the minimum inhibitory concentration. The results showed that among the three compounds, ODH exhibited the most potent antibacterial activity.
基金This work was supported by PRODEP throughthe support of the postdoctoral fellowship granted to the first author(Trade No.511-6/18-391)The authors thank the academic body of Ecología Aplicada(UAT-CA-156)for the support obtained from their researchers to conductthis investigation.
文摘The tomato(Solanum lycopersicum L.)is one of the world’s most important vegetable crops.Still,phytopathogenic bacteria affect the yield and quality of tomato cultivation,like Agrobacterium tumefeciens(At),Clavibacter michiganensis subsp.michiganensis(Cmm),Pseudomonas syringae pv.tomato(Pst),Ralstonia solanacearum(Rs),and Xanthomonas axonopodis(Xa).Synthetic chemical products are used mostly on disease plant control,but overuse generates resistance to bacterial control.This study aimed to evaluate the in vitro antibacterial activity of the ethanolic extract of Moringa oleifera Lam.leaves against At,Cmm,Pst,Rs,and Xa,as well as information about this plant species’chemical composition.Antibacterial activity against pathogens observed by microplate technique,phytochemical screening,and FTIR analysis revealed different bio-active compounds on ethanolic extracts with antibacterial activity.The growth inhibition rate ranged between 0.08%and 99.94%.The inhibitory concentration,IC50,required to inhibit 50%of At,Cmm,Pst,Rs,and Xa bacterial growth,was 276.67,350.48,277.85,351.49,and 283.22 mg/L,respectively.Inhibition of phytopathogen bacteria’s growth increased as the concentrations of the extract also increased.Moringa oleifera extract can be recommended as a potent bio-bactericide.
文摘Multiple drug resistant(MDR)and methicillin-resistant Staphylococcus aureus(MRSA)have become increasingly prevalent as a community acquired infection.As a result limited treatment options are available with conventional synthetic antibiotics.Bioprospecting natural products with potent antimicrobial activity show promise for developing new drugs against this pathogen.In this study,we have investigated the antimicrobial activity of a purple violet pigment(PVP)from an Antarctic bacterium,Janthinobacterium sp.Ant5-2 on 15 clinical MDR and MRSA strains.The colorimetric resazurin assay was employed to determine the minimum inhibitory concentration(MIC90)of PVP against MDR and MRSA.The MIC90 ranged between 1.57μg/mL and 3.13μg/mL,which are significantly lower than many antimicrobials tested from natural sources against this pathogen.The spectrophotometrically determined growth analysis and total microscopic counts using Live/dead®BacLight™fluorescent stain exhibited a steady decrease in viability of both MDR and MRSA cultures following treatment with PVP at the MIC levels.In silico predictive molecular docking study revealed that PVP could be a DNA-targeting minor groove binding antimicrobial compound.The continued development of novel antimicrobials derived from natural sources with the combination of a suite of conventional antibiotics could stem the rising pandemic of MDR and MRSA along with other deadly microbial pathogens.
文摘The antibacterial activity of methanol and acetone extracts of five plant extracts being utilized for the cure of different ailments in Pakistan was studied.The extracts of Curcuma zedoaria,Ipomea turpethum,Sphaeranthus indicus,Terminalia chebula and Tricholepis glaberrima were tested against seven different bacterial strains by well diffusion method and microdilution methods.The pattern of zone of inhibition varied with the plant extracts,the solvent used for extraction and organisms tested.Plant extracts(20 mg/mL) were used to evaluate antibacterial activities.The zone of inhibition exhibited by methanol extracts varied between 11 mm and 32 mm while those of acetone extracts varied between 9 mm and 25 mm respectively.The minimum inhibitory concentration(MIC) exhibited by methanol extracts ranged between(18.4-51.1) mg/mL.Overall methanolic extracts showed more activity than the acetone extracts against tested organisms except for S.indicus.The plants were also analyzed for their elemental composition using atomic absorption spectrophotometer to explore natural sources of essential elements that can be utilized for medicinal purposes.
文摘The purpose of this study was to first evaluate the antimicrobial effects of powder and extracts of berries (rose-hip, aronia, sea buckthorn and hawthorn) on the development of antibiotic-resistant <i><span style="font-family:Verdana;">L</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">monocitogenes</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">Listeria</span></i> <i><span style="font-family:Verdana;">monocytogenes</span></i><span style="font-family:Verdana;"> is considered one of the most important pathogens responsible for food-borne infection. Antimicrobial properties were evaluated using the standard Kirby-Bauer disk diffusion method. Bacterial inactivation networks were determined and compared, as well as the possibility of using powders and extracts of berries to control the risk of </span><i><span style="font-family:Verdana;">Listeria</span></i> <i><span style="font-family:Verdana;">monocytogees</span></i><span style="font-family:Verdana;"> infestation in the milk and dairy industry as well as in the meat industry. The effect of pH (4.78 - 4.43) and water activity (0.90 - 0.80) on the relationship between optical density (OD) at 600 nm and the plate count (CFU ml<sup>-</sup></span><span style="font-family:Verdana;"><sup>1</sup></span><span style="font-family:Verdana;">) was investigated for </span><i><span style="font-family:Verdana;">Listeria</span></i> <i><span style="font-family:Verdana;">monocytogenes</span></i><span style="font-family:Verdana;">. It was determined Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) </span><span style="font-family:Verdana;">of berries for</span><span style="font-family:;" "=""> </span><i><span style="font-family:Verdana;">L. monocytogenes</span></i><span style="font-family:Verdana;">. </span><span style="font-family:Verdana;">The most relevant bacteriostatic and bactericidal </span><span style="font-family:;" "=""><span style="font-family:Verdana;">effect on </span><i><span style="font-family:Verdana;">L. monocytogenes</span></i><span style="font-family:Verdana;"> in the tested berries demonstrated sea buckthorn and rosehip.</span></span>
