[ Objective ] The aim was to research the antimicrobial effect of the extracts of Clerodendron bungei roots with different solvents on the common plant microbes. [ Method] The bacteria cake method was used to study th...[ Objective ] The aim was to research the antimicrobial effect of the extracts of Clerodendron bungei roots with different solvents on the common plant microbes. [ Method] The bacteria cake method was used to study the antimicrobial capability of Clerodendron bungei roots. [ Result ] The extracts have anti-bacterial action on Rhixoctonia cerealis V. Hoeven, Fusarium graminearum, Rhizoctonia solani and Setosphaeria turcica, especially the extract from distilled water has the strongest anti-bacterial action on Rhixoctonia cerealis V. Hoeven and Fusarium graminearum, the extract from ether has the strongest anti-bacterial action on Fusarium graminearum, the MIC all were 10 mg/ml. The extracts had different antimicrobial effect when pH value was from 5 to 8[ Conclusion] The extracts of Clerodendron bungei roots could inhibit the 4 pathogenic microorganism, and the antibacterial activity was affected by pH value greatly.展开更多
Objective:To synthesize silver nanopaticles from leaves extract of Eucalyptus chapmaniana(E.chapmaniana)and test the antimicrobial of the nanoparticles against different pathogenic bacteria,yeast and its toxicity agai...Objective:To synthesize silver nanopaticles from leaves extract of Eucalyptus chapmaniana(E.chapmaniana)and test the antimicrobial of the nanoparticles against different pathogenic bacteria,yeast and its toxicity against human acute promyelocytic leukemia(HL-60)cell line.Methods:Ten milliliter of leaves extract was mixed with 90 mL of 0.01 mmol/mL or 0.02 mmol/mL aqueous AgNO_3 and exposed to sun light for 1 h.A change from yellowish to reddish brown color was observed.Characterization using UV-vis spectrophotometery and X-ray diffraction analysis were performed.Antimicrobial activity against six microorganisms was tested using well diffusion method and cytoxicity test using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide,a yellow tetrazole was obtained on the human leukemia cell line(HL-60).Results:UV-vis spectral analysis showed silver surface plasmon resonance band at 413 nm.X-ray diffraction showed that the particles were crystalline in nature with face centered cubic structure of the bulk silver with broad beaks at 38.50°and 44.76°.The synthesized silver nanoparticles efficiently inhibited various pathogenic organisms and reduced viability of the HL-60 cells in a dose-dependent manner.Conclusions:It has been demonstrated that the extract of E.chapmaniana leaves are capable of producing silver nanoparticles extracellularly and the Ag nanoparticles are quite stable in solution.Further studies are needed to fully characterize the toxicity and the mechanisms involved with the antimicrobial and anticancer activity of these particles.展开更多
The antibiotic therapy has many problems, such as antibiotics resistance, hypersensitivity, direct toxicity, antibiotic-induced immunosuppresion and super-infections. This is highlighting the need for a new strategy f...The antibiotic therapy has many problems, such as antibiotics resistance, hypersensitivity, direct toxicity, antibiotic-induced immunosuppresion and super-infections. This is highlighting the need for a new strategy for non-antibiotic therapy through the use of novel immunomodulators as naturally released ones (Lactoferrin). The present study investigates the potential of bovine lactoferrin (bLf), isolated from bovine milk whey, to prevent Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), Streptococcus agalactiae (S. agalactiae) and Pseudomonas aeruginosa (P. aerogenosa) growth and then evaluates its immunomodulator effect. First, bLf isolation was attempted from bovine milk whey using a cation exchange chromatography by SP-Sepharose. Second, the antimicrobial activity assays were trailed to study the antimicrobial activity of bLf. Finally, the immune effect of bLf was studied by lymphocyte transformation test. It was found that bLf was separated around molecular weight of 80 kDa and showed significant inhibitory effect against E. coli followed by P. aeruginosa, S. agalactiae and S. aureus. bLf increased lymphocyte transformations mean values in a dose dependant manner. The highest transformations mean value was determined at 50 μg/mL. In conclusion, these results suggest that bLf is a potent natural antimicrobials and immunomodulator agent.展开更多
Biofilms at the tooth-restoration bonded interface can produce acids and cause recurrent caries. Recurrent caries is a primary reason for restoration failures. The objectives of this study were to synthesize a novel b...Biofilms at the tooth-restoration bonded interface can produce acids and cause recurrent caries. Recurrent caries is a primary reason for restoration failures. The objectives of this study were to synthesize a novel bioactive dental bonding agent containing dimethylaminohexadecyl methacrylate(DMAHDM) and 2-methacryloyloxyethyl phosphorylcholine(MPC) to inhibit biofilm formation at the tooth-restoration margin and to investigate the effects of water-aging for 6 months on the dentin bond strength and protein-repellent and antibacterial durability. A protein-repellent agent(MPC) and antibacterial agent(DMAHDM) were added to a Scotchbond multi-purpose(SBMP) primer and adhesive. Specimens were stored in water at 37 °C for 1, 30, 90, or 180 days(d).At the end of each time period, the dentin bond strength and protein-repellent and antibacterial properties were evaluated. Protein attachment onto resin specimens was measured by the micro-bicinchoninic acid approach. A dental plaque microcosm biofilm model was used to test the biofilm response. The SBMP + MPC + DMAHDM group showed no decline in dentin bond strength after water-aging for 6 months, which was significantly higher than that of the control(P < 0.05). The SBMP + MPC + DMAHDM group had protein adhesion that was only 1/20 of that of the SBMP control(P < 0.05). Incorporation of MPC and DMAHDM into SBMP provided a synergistic effect on biofilm reduction. The antibacterial effect and resistance to protein adsorption exhibited no decrease from 1 to 180 d(P > 0.1). In conclusion, a bonding agent with MPC and DMAHDM achieved a durable dentin bond strength and long-term resistance to proteins and oral bacteria. The novel dental bonding agent is promising for applications in preventive and restorative dentistry to reduce biofilm formation at the tooth-restoration margin.展开更多
Objective:To investigate the in vitro antimicrobial potential of Thermopsis turcica Kit Tan,Vural&Kckdk against periodoutopathogenie bacteria,its antioxidant activity and cytotoxic effect on various cancer...Objective:To investigate the in vitro antimicrobial potential of Thermopsis turcica Kit Tan,Vural&Kckdk against periodoutopathogenie bacteria,its antioxidant activity and cytotoxic effect on various cancer cell lines.Methods:In vitro antimicrobial activities of elhanol.methanol,ethyl acetate(ElAc,n-hexane and water extracts of Thermopsis turcica herb against periodontopathogenic bacteria,Aggregatibacter actinnmycelemconilans ATCC 29523 and Porphyromonas gingivalis ATCC 33277 were tested by agar well diffusion,minimum inhibitory concentration(MIC)and minimal bactericidal concentration(MBC),Antioxidant properties of the extracts were evaluatod by 1,1-diphenyl-2-picryl-hydrazyl radical scavenging activity and p-carotene bleaching methods.Amounts of phenolic contents of the extracts were also analysed by using the Folin-Ciocalteu reagent.Additionally,cytotoxic activity of the extracts on androgcn-insensilivc prostate cancer,androgen—sensitive prostate cancer,chronic myelogenous leukemia and acute promyelocytic leukemia bunian cancer cell lines were determined by 3-4,5-dimelhylthiazol-2-yh-2,5-diphenyltclrazolium bromide assay.Human gingival fibroblast cells were used as a control.Results:Our data showed that ELAc extract had the highest antimicrobial effect on Aggregatibacter actinomycetemitans(MIC:1.562 mg/ml_MHC:3.124 mg/ml.)and Porph yromonas gingiralis(MIC:0.781 mg/mL,MBC:1.562 mg/mL).In antioxidant assays.ElAc extract exhibited also the highest radical scavenging activity[IC_(50)=(30.0±0.3)μg/ml.]and the highest inhibition[(74.35±0.30)%]|against lineloic acide oxidation.The amount of phenolic content of it was also the highest[(l62.5±l.2)μg/mg gallic acid].In cytotoxic assay,only etbanol[IC_(50)=(80.00±1.21)μg/ml.]and EtAc extract[IC_(50)=(70.0±0.9)μg/ml]were toxic on acute promyeloeytic leukemia cells at 20—100μg/mL.P<0.05>.However,no toxic effect was observed on human gingival fibroblast cells.Cunclusions:According to our findings,owing to its antioxidant and cytotoxic potential,EtAc exlrael might include anticancer agents for acute promyelocytic leukemia.展开更多
The human and bovine lactoferrin have been studied extensively, but very few reports have been published concerning camel lactoferrin (cLf). The present study aimed to isolate cLf and evaluate its efficiency including...The human and bovine lactoferrin have been studied extensively, but very few reports have been published concerning camel lactoferrin (cLf). The present study aimed to isolate cLf and evaluate its efficiency including antimicrobial activity and immunomodulator effects. cLf isolation was attempted from camel milk whey using a cation exchange chromatography by SP-Sepharose. The antimicrobial activity of the isolated cLf was investigated against Staphylococcus aureus (S. aureus), Streptococcus agalactiae (S. agalactiae), Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aerogenosa) strains. The immune effect of cLf was studied by lymphocyte transformation test. It was found that cLf was separated around molecular weight of 80 kDa and showed significant inhibitory effect against E. coli followed by P. aeruginosa, S. agalactiae and S. aureus. cLf increased lymphocyte transformations mean values in a dose dependant manner. The highest transformations mean value was determined at 50 μg/mL. In conclusion, these results suggest that cLf is a potent natural antimicrobial and novel immunomodulator agent.展开更多
<strong>Purpose:</strong> To investigate the effect of silver ionised water on acid production in plaque. <strong>Methods: </strong>After injecting 0.5 mL of silver ionised water (concentration...<strong>Purpose:</strong> To investigate the effect of silver ionised water on acid production in plaque. <strong>Methods: </strong>After injecting 0.5 mL of silver ionised water (concentration: 5 ppm) produced with the sintering coating method in the sensor part of the pH metre, plaque collected from the oral cavity by one platinum loop was mixed in. Immediately after that, a 5% sucrose solution (1 g/20 mL) was added and the pH was continuously measured for 30 minutes at 1-minute intervals (A). Similarly, silver ionised water was mixed with 5% sucrose solution in the same way as in (A) at 3 (B), 5 (C), 10 (D) and 15 minutes (E) after plaque contamination. The pH was measured at 1-minute intervals. The pH of the purified water containing no silver ionised water mixed with plaque and sugar solution at the same time was measured and used as a control. Each experiment was conducted three times, and the pH measured every minute was compared as a percentage of the pH at the beginning of the measurement (100%). <strong>Results:</strong> Analysis of variance of the repeated measurements to determine the effect of silver ionised water on the decrease in pH revealed a main effect of silver ionised water and an interaction between time and group [F<sub>(1.302,20.826)</sub> = 39.145, p < 0.01]. Multiple comparisons using Dunnett’s method showed a significant decline in the rate of decrease in pH from B to E as compared with that in the control (p < 0.01). <strong>Conclusion: </strong>Silver ionised water was found to inhibit the acid production in plaque.展开更多
One of the most important functions of skins is to protect our bodies from microbes or pollutant sources. Skins containing physical substances serve as a physical barrier which protects our bodies from pathogens. A he...One of the most important functions of skins is to protect our bodies from microbes or pollutant sources. Skins containing physical substances serve as a physical barrier which protects our bodies from pathogens. A healthy skin contains a variety of antibacterial substances such as defensin, cathelicidin and psoriasin. However deep and wide burns cause the skin to lose its original functions, so our skins are exposed to various danger factors. For the burn patients, human alloskin graft serves as a very important temporary biological wound dressing. It protects the wound before autograft procedure, forms revascularization and granulation tissues and protects the wound from an invasion of microbes. This study was conducted with the aim to analyze the antimicrobial effect of cryopreserved allograft (CPA) and glycerol-preserved allograft (GPA) which was a type of allograft widely used for burn patients, and measure the difference in comparison with the fresh skin before processing it. The most common contaminants found in burn patients such as S. aureus, P. aeruginosa, C. albicans and E. coli, were used for experiment. The antimicrobial effect against S. aureus and E. coli was observed in fresh skin and some CPA. In some clinical cases, infection is frequently observed in the wounds treated with allograft, indicating the allograft completely block every kind of microbes. To prevent the infection, it is required to use antibiotics and manage wounds thoroughly.展开更多
Antimicrobial and photocatalytic effect of silicate and silicone paints were tested. Silicate paints are based on water styrene-acrylic dispersion with mineral binder into form of potassium water glass. Silicone paint...Antimicrobial and photocatalytic effect of silicate and silicone paints were tested. Silicate paints are based on water styrene-acrylic dispersion with mineral binder into form of potassium water glass. Silicone paints are based on water acrylic dispersion with silicone resin emulsion. Silicate and silicone paints were formulated with photocatalytic active nanooxides TiO2 and ZnO. Photocatalytic efficiency of coatings was measured as an absorbance change of organic dye Orange II solution at a wavelength of 485 nm. Antimicrobial properties of coatings were tested using agar plate methods. As test microorganisms Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Penicillium chrysogenum and Aspergillus niger suspension (density 10^6 cells/mL) were used. The inhibition effect of tested coatings and inhibitory zones were evaluated after incubation. Coatings containing nanoparticles of titanium dioxide and zinc oxide showed antimicrobial activity against the test microorganisms. Whereas coating with zinc oxide nanoparticles successfully inhibited the growth of both bacteria and fungi, the photocatalytic nanoparticles of titanium dioxide inhibited bacteria but not fungi (weak inhibition was observed).展开更多
Background: A series of modified montmorillonites(Mt) including zinc-loaded Mt(Zn-Mt), copper-loaded Mt(Cu-Mt), copper/zinc-loaded Mt with different Cu/Zn ratio(Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3) were prepar...Background: A series of modified montmorillonites(Mt) including zinc-loaded Mt(Zn-Mt), copper-loaded Mt(Cu-Mt), copper/zinc-loaded Mt with different Cu/Zn ratio(Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3) were prepared by an ion-exchange reaction, and characterized using X-ray diffraction(XRD), fourier transformed infrared spectroscopy(FTIR) and transmission electron microscopy(TEM). The specific surface areas, antimicrobial activity and cytotoxicity of the modified Mt were investigated.Results: In the modified Mt, hydrated Cu ions and Zn ions were exchanged in the interlayer space of Mt and the particles were irregular shapes. The results showed that Cu/Zn-Mt enhanced antibacterial and antifungal activity compared with Zn-Mt and Cu-Mt possibly due to the synergistic effect between Cu and Zn. Among the Cu/Zn-Mt with different Cu/Zn raitos, Cu/Zn-Mt with a Cu/Zn ratio of 0.98 or 0.51 showed higher antimicrobial activity against gram-negative bacteria(Escherichia coli), gram-positive bacteria(Staphylococcus aureus), fungi(Candida albicans).Moreover, the antimicrobial activity of Cu/Zn-Mt was correlated with its specific surface area. Cytotoxicity studies on IPEC-J2 cell showed a slight cytotoxicity of Cu/Zn-Mt.Conclusions: The current data provide clear evidence that in terms of its antimicrobial activity and relatively low toxicity, the Cu/Zn-Mt holds great promise for applications in animal husbandry.展开更多
The present work is devoted to the study of antiradical and antimicrobial activities of phenolic compounds extracted from different grapevine varieties grown in the Bekaa plane-Lebanon. The amount of phenolic compound...The present work is devoted to the study of antiradical and antimicrobial activities of phenolic compounds extracted from different grapevine varieties grown in the Bekaa plane-Lebanon. The amount of phenolic compounds in selected grape extracts was determined by the Folin-Ciocalteau method. Phenolic composition was specified by high performance liquid chromatography. Free radical scavenging activity was examined by using the (2,2’-diphenyl-1-picrylhy-drazyl) DPPH assay. The potential antimicrobial activity was studied using a new quantitative method developed during this work. This activity was tested against several microbial pathogens, including a Gram-positive strain (Listeria monocytogenes), two Gram-negative strains (Escherichia coli and Salmonella arizonae) and a fungal strain (Candida albicans). According to the results of the present screening study, a great variability in the composition of phenolic com-pounds in red grape extracts was detected. All phenolic compounds extracts, demonstrated important scavenging properties and antimicrobial effect against bacterial and fungal strains. Yet, a different response degree was noticed depending on the tested microorganism and the phenolic composition of grape extracts. Antimicrobial activity was more effective against Gram-positive than Gram-negative and yeast strains. Furthermore, our results highlighted a significant role of synergistic effect between various phenolic compounds in the free radical scavenging and antimicrobial activities.展开更多
AIM To investigate osteoconductive and antimicrobial properties of a titanium-copper-nitride(TiC uN) film and an additional BONIT~? coating on titanium substrates.METHODS For micro-structuring, the surface of titanium...AIM To investigate osteoconductive and antimicrobial properties of a titanium-copper-nitride(TiC uN) film and an additional BONIT~? coating on titanium substrates.METHODS For micro-structuring, the surface of titanium test samples was modified by titanium plasma spray(TPS). On the TPS-coated samples, the Ti Cu N layer was deposited by physical vapor deposition. The BONIT~? layer was coated electrochemically. The concentration of copper ions released from TiC uN films was measured by atomic absorption spectrometry. MG-63 osteoblasts on Ti Cu N and BONIT~? were analyzed for cell adhesion, viability and spreading. In parallel, Staphylococcus epidermidis(S. epidermidis) were cultivated on the samples and planktonic and biofilm-bound bacteria were quantified bycounting of the colony-forming units. RESULTS Field emission scanning electron microscopy(FESEM) revealed rough surfaces for TPS and TiC uN and a special crystalline surface structure on TiC uN + BONIT~?. TiC uN released high amounts of copper quickly within 24 h. These release dynamics were accompanied by complete growth inhibition of bacteria and after 2 d, no planktonic or adherent S. epidermidis were found on these samples. On the other hand viability of MG-63 cells was impaired during direct cultivation on the samples within 24 h. However, high cell colonization could be found after a 24 h pre-incubation step in cell culture medium simulating the in vivo dynamics closer. On pre-incubated TiC uN, the osteoblasts span the ridges and demonstrate a flattened, well-spread phenotype. The additional BONIT~?-coating reduced the copper release of the TiC uN layer significantly and showed a positive effect on the initial cell adhesion.CONCLUSION The Ti Cu N-coating inhibits the formation of bacterial biofilms on orthopedic implants by influencing the "race for the surface" to the advantage of osteoblasts.展开更多
Objective: To evaluate the antimicrobial, antioxidant, cytotoxicity and anticancer activity of fractions from Jatropha zeyheri roots and to explore the phytochemical profile of the most biologically active fraction.Me...Objective: To evaluate the antimicrobial, antioxidant, cytotoxicity and anticancer activity of fractions from Jatropha zeyheri roots and to explore the phytochemical profile of the most biologically active fraction.Methods: Fractions from Jatropha zeyheri ethyl acetate extract were investigated for antimicrobial activity against a plethora of pathogenic microorganisms of different origins. The cytotoxicity studies of fractions were evaluated in vitro using tetrazolium-based calorimetric assay against human dermal fibroblast, colon adenocarcinoma(Caco-2), breast cancer(MCF-7) and lung cancer(A547) cell lines. The anti-oxidant activity of fractions was determined in vitro against 2,2-diphenyl-1-picrylhydrazyl(DPPH), 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt(ABTS) and chelation of iron(Fe2+). Gas chromatography mass spectrometry analysis was performed to detect phytochemical constituents in fraction with potent biological activity.Results: Fraction 2 of Jatropha zeyheri roots exhibited the lowest minimum inhibitory concentration of 40 μg/mL against Klebsiella pneumoniae and 80 μg/mL against Candida albicans, Staphylococcus aureus and Mycoplasma hominis. The fractions revealed some varying degrees of cytotoxicity against human dermal fibroblasts yielding LC50 values ranging from 28.96 to 166.52 μg/mL. Fraction 3 exhibited the highest selectivity index value of 2.08 against Klebsiella pneumoniae. Moreover, fraction 2 selectively inhibited the growth of Caco-2 with LC50 of 8.83 μg/mL, compared to other cancerous cell lines. Fraction 2 of Jatropha zeyheri further exhibited IC50 of 19.66, 22.63 and 1.82 μg/mL against DPPH, ABTS and Fe2+, respectively. Gas chromatography mass spectrometry analysis revealed the presence of cyclotetracosane(10.08%), 9-hexacosene(9.40%), hexadecanoic acid(3.90%),(Z)-9-octadecenamide(3.63%), octacosane(2.27%), 11-n-decylheneicosane(2.23%), ethyl vallesiachotamate(2.17%), heneicosanoic acid(2.10%), and octadecanoic acid(2.08%) in fraction 2 of Jatropha zeyheri.Conclusions: These identified compounds, particularly cyclotetracosane(hydrocarbon), may well explain the biological activity of fraction 2 of Jatropha zeyheri, which possesses higher biological activity than other fractions. These compounds can be further investigated for use in treating various bacterial and fungal opportunistic infections associated with HIV-AIDS and related cancers.展开更多
In the present study,the green synthesis of potassium nanoparticles(K-NPs)was assessed using aqueous extract of Sideroxylon capiri.The potassium nanoparticles were analyzed by UV-visible spectroscopic techniques,X-ray...In the present study,the green synthesis of potassium nanoparticles(K-NPs)was assessed using aqueous extract of Sideroxylon capiri.The potassium nanoparticles were analyzed by UV-visible spectroscopic techniques,X-ray spectrometers of energy dispersive(SEM-EDS)and dynamic light scattering.The results showed high values at 3.5 keV confirming the formation of potassium nanoparticles and the SEM analysis showed an agglomerated particles size between 360 to 200 nm with a spherical morphology.The K-NPs showed an effective antibacterial activity against the test organisms mainly with Bacillus cereus,Enterobacter aerogenes,Fusarium solani and Botrytis cinerea.However further studies about nanotoxicity of K-NPs are needed to confirm their potential in the control of the pathogen microorganisms under field conditions.展开更多
Backgroud: This study aimed to determine the effects of early antibiotic intervention(EAI) on subsequent blood parameters, apparent nutrient digestibility, and fecal fermentation profile in pigs with different diet...Backgroud: This study aimed to determine the effects of early antibiotic intervention(EAI) on subsequent blood parameters, apparent nutrient digestibility, and fecal fermentation profile in pigs with different dietary crude protein(CP) levels. Eighteen litters of piglets(total 212) were randomly allocated to 2 groups and were fed a creep feed diet with or without in-feed antibiotics(olaquindox, oxytetracycline calcium and kitasamycin) from postnatal d 7 to d 42. On d 42, the piglets within the control or antibiotic group were mixed, respectively, and then further randomly assigned to a normal-(20%, 18%, and 14% CP from d 42 to d 77, d 77 to d 120, and d 120 to d 185,respectively) or a low-CP diet(16%, 14%, and 10% CP from d 42 to d 77, d 77 to d 120, and d 120 to d 185,respectively), generating 4 groups. On d 77(short-term) and d 185(long-term), serum and fecal samples were obtained for blood parameters, microbial composition and microbial metabolism analysis.Results: EAI increased(P 〈 0.05) albumin and glucose concentrations in low-CP diet on d 77, and increased(P 〈 0.05) urea concentration in normal-CP diet. On d 185, EAI increased(P 〈 0.05) globulin concentration in normal-CP diets, but decreased glucose concentration. For nutrient digestibility, EAI increased(P 〈 0.05)digestibility of CP on d 77. For fecal microbiota, the EAI as well as low-CP diet decreased(P 〈 0.05) E. coli count on d 77. For fecal metabolites, on d 77, EAI decreased(P 〈 0.05) total amines concentration but increased skatole concentration in low-CP diet. On d 185, the EAI increased(P 〈 0.05) putrescine and total amines concentrations in low-CP diets but reduced(P 〈 0.05) in the normal-CP diets. The low-CP diet decreased the concentrations of these compounds.Conclusions: Collectively, these results indicate that EAI has short-term effects on the blood parameters and fecal microbial fermentation profile. The effects of EAI varied between CP levels, which was characterized by the significant alteration of glucose and putrescine concentration.展开更多
Objective:This study has been done to evaluate the interaction between water extracts of Psidium guajava, Rosmarinus officinalis,Salvia fruticosa,Majorana syriaca,Ocimum basilucum,Syzygium aromaticum,Laurus nobilis,an...Objective:This study has been done to evaluate the interaction between water extracts of Psidium guajava, Rosmarinus officinalis,Salvia fruticosa,Majorana syriaca,Ocimum basilucum,Syzygium aromaticum,Laurus nobilis,and Rosa damascena alone and then synergy testing of these extracts with known antimicrobial agents including oxytetracycline HCl,gentamicin sulfate,penicillin G,cephalexin and enrofloxacin.This study was conducted against five S.aureus isolates;one is Methicillin -resistant Staphylococcus aureus(MRSA) and 4 Methicillin - sensitive Staphylococcus aureus(MSSA).Methods:Evaluation of the interaction between plant extracts and different antimicrobial agents has been done using well - diffusion and microdilution methods. Results:The results of the conducted experiments using well - diffusion method demonstrate that these plants showed in vitro interactions between antimicrobial agents and plant extracts were additive,while using microdilution method showed synergistic effects with significant reduction in the MICs of the test antibiotics against these strains of S.aureus.This change in MIC was noticed in all plant extracts against test antibiotics including these plants showed weak antibacterial activity by well diffusion method.Synergism effect was occurred in both sensitive and resistant strains but the magnitude of minimum fold reduction of inhibitory concentration in resistant strains especially MRSA strain was higher than the sensitive strains.Coclusion:This study probably suggests the possibility of concurrent use of these antimicrobial drugs and plant extracts in combination in treating infections caused by S.aureus strains or at least the concomitant administration may not impair the antimicrobial activity of these antibiotics.展开更多
Background: Laboratory personnel is at risk of biological contamination leading to laboratory-acquired infections (LAIs). The use of disinfection products is essential in the prevention of these infections. This work ...Background: Laboratory personnel is at risk of biological contamination leading to laboratory-acquired infections (LAIs). The use of disinfection products is essential in the prevention of these infections. This work aimed to evaluate the effectiveness of antimicrobial agents used in disinfection in bacteriology laboratories in Togo. Methods: This was a cross-sectional study conducted from June to December 2021 in all bacteriology laboratories in Togo. Swabs taken before and after disinfection of surfaces and staff hands were immediately plated on agar media. Counting and identification of isolated colonies were done after 24 hours of incubation. The ANOVA test was used to compare calculated means, prevalence ratio (PR) and 95% confidence intervals (CI) to compare bacterial frequencies. Results: A total of 393 samples were taken, of which 41.2% were from hands. Before disinfection, surfaces were more contaminated than hands with respectively 40.4% and 29.6% (PR = 1.3;CI 95% = [0.9 - 1.9]). After surface disinfection with 0.5% of chlorine solution, bacterial elimination was total, but partial on hands washed with soap, with residual contamination of 3.7%. A total of 108 strains were isolated before disinfection of which Klebsiella spp. 38.9% and Staphylococcus spp. 25.0%;after disinfection 4 strains were isolated of which: Staphylococcus spp. 75.0% and Klebsiella spp. 25.0%. Conclusion: Surface disinfection was more effective than hand washing with soap and water. We recommend proper hand washing.展开更多
[Objectives] This study was conducted to determine in-vitro antibacterial effect of 58 Chinese herbs on Staphylococcus aureus,and screen single Chinese herbs with better in-vitro antibacterial effect for formulation o...[Objectives] This study was conducted to determine in-vitro antibacterial effect of 58 Chinese herbs on Staphylococcus aureus,and screen single Chinese herbs with better in-vitro antibacterial effect for formulation of prescription. [Methods]Effective components in Chinese herbs were extracted with water,and inhibition zone diameters and minimal inhibitory concentrations of the 58 Chinese herbs against S. aureus were determined by agar plate punching method and micro two-fold method,respectively. [Results] Twenty two kinds of Chinese herbs including Terminalia chebula Retz.,Anemarrhena asphodeloides Bunge.,Prunella vulgaris L,Rheum palmatum L. and Mosla chinensis Maxim. had better antibacterial effect,among which T. chebula Retz.,A. asphodeloides Bunge.,P. vulgaris L,R. palmatum L. and C. sappan Linn showed the best antibacterial effect,with average inhibition zone over 20 mm and MIC lower than 15. 6 mg/ml.[Conclusions]Traditional Chinese herbs have certain antibacterial effect,and this study will provide important theoretical reference for clinical medication and development of prescription.展开更多
基金Supported by Youth Foundation of Yibin University(QJ05-22)Research Fund for the Doctoral Program of Yibin University(2005B02)~~
文摘[ Objective ] The aim was to research the antimicrobial effect of the extracts of Clerodendron bungei roots with different solvents on the common plant microbes. [ Method] The bacteria cake method was used to study the antimicrobial capability of Clerodendron bungei roots. [ Result ] The extracts have anti-bacterial action on Rhixoctonia cerealis V. Hoeven, Fusarium graminearum, Rhizoctonia solani and Setosphaeria turcica, especially the extract from distilled water has the strongest anti-bacterial action on Rhixoctonia cerealis V. Hoeven and Fusarium graminearum, the extract from ether has the strongest anti-bacterial action on Fusarium graminearum, the MIC all were 10 mg/ml. The extracts had different antimicrobial effect when pH value was from 5 to 8[ Conclusion] The extracts of Clerodendron bungei roots could inhibit the 4 pathogenic microorganism, and the antibacterial activity was affected by pH value greatly.
基金Supported by University of Technology.Baghdad.Iraq and Universiti Kebangsaan Malaysia(Grant No.DIP-2012-02)
文摘Objective:To synthesize silver nanopaticles from leaves extract of Eucalyptus chapmaniana(E.chapmaniana)and test the antimicrobial of the nanoparticles against different pathogenic bacteria,yeast and its toxicity against human acute promyelocytic leukemia(HL-60)cell line.Methods:Ten milliliter of leaves extract was mixed with 90 mL of 0.01 mmol/mL or 0.02 mmol/mL aqueous AgNO_3 and exposed to sun light for 1 h.A change from yellowish to reddish brown color was observed.Characterization using UV-vis spectrophotometery and X-ray diffraction analysis were performed.Antimicrobial activity against six microorganisms was tested using well diffusion method and cytoxicity test using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide,a yellow tetrazole was obtained on the human leukemia cell line(HL-60).Results:UV-vis spectral analysis showed silver surface plasmon resonance band at 413 nm.X-ray diffraction showed that the particles were crystalline in nature with face centered cubic structure of the bulk silver with broad beaks at 38.50°and 44.76°.The synthesized silver nanoparticles efficiently inhibited various pathogenic organisms and reduced viability of the HL-60 cells in a dose-dependent manner.Conclusions:It has been demonstrated that the extract of E.chapmaniana leaves are capable of producing silver nanoparticles extracellularly and the Ag nanoparticles are quite stable in solution.Further studies are needed to fully characterize the toxicity and the mechanisms involved with the antimicrobial and anticancer activity of these particles.
文摘The antibiotic therapy has many problems, such as antibiotics resistance, hypersensitivity, direct toxicity, antibiotic-induced immunosuppresion and super-infections. This is highlighting the need for a new strategy for non-antibiotic therapy through the use of novel immunomodulators as naturally released ones (Lactoferrin). The present study investigates the potential of bovine lactoferrin (bLf), isolated from bovine milk whey, to prevent Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), Streptococcus agalactiae (S. agalactiae) and Pseudomonas aeruginosa (P. aerogenosa) growth and then evaluates its immunomodulator effect. First, bLf isolation was attempted from bovine milk whey using a cation exchange chromatography by SP-Sepharose. Second, the antimicrobial activity assays were trailed to study the antimicrobial activity of bLf. Finally, the immune effect of bLf was studied by lymphocyte transformation test. It was found that bLf was separated around molecular weight of 80 kDa and showed significant inhibitory effect against E. coli followed by P. aeruginosa, S. agalactiae and S. aureus. bLf increased lymphocyte transformations mean values in a dose dependant manner. The highest transformations mean value was determined at 50 μg/mL. In conclusion, these results suggest that bLf is a potent natural antimicrobials and immunomodulator agent.
基金the Natural Science Foundation of China NSFC 81500879(N.Z.),81400540(K.Z.)the Beijing Municipal Science and Technology Commission Z151100003915137(N.Z.)+2 种基金the Beijing Municipal Administration of Hospitals’YouthProgram QML20161501(N.Z.),QML20151401(K.Z.)the Beijing Municipal Hospitals’Program ZYLX201703(Y.B.),NIH R01 DE17974(H.X.)a Seed Grant(H.X.)from the University of Maryland School of Dentistry
文摘Biofilms at the tooth-restoration bonded interface can produce acids and cause recurrent caries. Recurrent caries is a primary reason for restoration failures. The objectives of this study were to synthesize a novel bioactive dental bonding agent containing dimethylaminohexadecyl methacrylate(DMAHDM) and 2-methacryloyloxyethyl phosphorylcholine(MPC) to inhibit biofilm formation at the tooth-restoration margin and to investigate the effects of water-aging for 6 months on the dentin bond strength and protein-repellent and antibacterial durability. A protein-repellent agent(MPC) and antibacterial agent(DMAHDM) were added to a Scotchbond multi-purpose(SBMP) primer and adhesive. Specimens were stored in water at 37 °C for 1, 30, 90, or 180 days(d).At the end of each time period, the dentin bond strength and protein-repellent and antibacterial properties were evaluated. Protein attachment onto resin specimens was measured by the micro-bicinchoninic acid approach. A dental plaque microcosm biofilm model was used to test the biofilm response. The SBMP + MPC + DMAHDM group showed no decline in dentin bond strength after water-aging for 6 months, which was significantly higher than that of the control(P < 0.05). The SBMP + MPC + DMAHDM group had protein adhesion that was only 1/20 of that of the SBMP control(P < 0.05). Incorporation of MPC and DMAHDM into SBMP provided a synergistic effect on biofilm reduction. The antibacterial effect and resistance to protein adsorption exhibited no decrease from 1 to 180 d(P > 0.1). In conclusion, a bonding agent with MPC and DMAHDM achieved a durable dentin bond strength and long-term resistance to proteins and oral bacteria. The novel dental bonding agent is promising for applications in preventive and restorative dentistry to reduce biofilm formation at the tooth-restoration margin.
基金Supported by Minsitry of Devetopment of Tuckish Republie for Foundation of Moleculer Biology Research Center(Grant No.1998K121480)
文摘Objective:To investigate the in vitro antimicrobial potential of Thermopsis turcica Kit Tan,Vural&Kckdk against periodoutopathogenie bacteria,its antioxidant activity and cytotoxic effect on various cancer cell lines.Methods:In vitro antimicrobial activities of elhanol.methanol,ethyl acetate(ElAc,n-hexane and water extracts of Thermopsis turcica herb against periodontopathogenic bacteria,Aggregatibacter actinnmycelemconilans ATCC 29523 and Porphyromonas gingivalis ATCC 33277 were tested by agar well diffusion,minimum inhibitory concentration(MIC)and minimal bactericidal concentration(MBC),Antioxidant properties of the extracts were evaluatod by 1,1-diphenyl-2-picryl-hydrazyl radical scavenging activity and p-carotene bleaching methods.Amounts of phenolic contents of the extracts were also analysed by using the Folin-Ciocalteu reagent.Additionally,cytotoxic activity of the extracts on androgcn-insensilivc prostate cancer,androgen—sensitive prostate cancer,chronic myelogenous leukemia and acute promyelocytic leukemia bunian cancer cell lines were determined by 3-4,5-dimelhylthiazol-2-yh-2,5-diphenyltclrazolium bromide assay.Human gingival fibroblast cells were used as a control.Results:Our data showed that ELAc extract had the highest antimicrobial effect on Aggregatibacter actinomycetemitans(MIC:1.562 mg/ml_MHC:3.124 mg/ml.)and Porph yromonas gingiralis(MIC:0.781 mg/mL,MBC:1.562 mg/mL).In antioxidant assays.ElAc extract exhibited also the highest radical scavenging activity[IC_(50)=(30.0±0.3)μg/ml.]and the highest inhibition[(74.35±0.30)%]|against lineloic acide oxidation.The amount of phenolic content of it was also the highest[(l62.5±l.2)μg/mg gallic acid].In cytotoxic assay,only etbanol[IC_(50)=(80.00±1.21)μg/ml.]and EtAc extract[IC_(50)=(70.0±0.9)μg/ml]were toxic on acute promyeloeytic leukemia cells at 20—100μg/mL.P<0.05>.However,no toxic effect was observed on human gingival fibroblast cells.Cunclusions:According to our findings,owing to its antioxidant and cytotoxic potential,EtAc exlrael might include anticancer agents for acute promyelocytic leukemia.
文摘The human and bovine lactoferrin have been studied extensively, but very few reports have been published concerning camel lactoferrin (cLf). The present study aimed to isolate cLf and evaluate its efficiency including antimicrobial activity and immunomodulator effects. cLf isolation was attempted from camel milk whey using a cation exchange chromatography by SP-Sepharose. The antimicrobial activity of the isolated cLf was investigated against Staphylococcus aureus (S. aureus), Streptococcus agalactiae (S. agalactiae), Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aerogenosa) strains. The immune effect of cLf was studied by lymphocyte transformation test. It was found that cLf was separated around molecular weight of 80 kDa and showed significant inhibitory effect against E. coli followed by P. aeruginosa, S. agalactiae and S. aureus. cLf increased lymphocyte transformations mean values in a dose dependant manner. The highest transformations mean value was determined at 50 μg/mL. In conclusion, these results suggest that cLf is a potent natural antimicrobial and novel immunomodulator agent.
文摘<strong>Purpose:</strong> To investigate the effect of silver ionised water on acid production in plaque. <strong>Methods: </strong>After injecting 0.5 mL of silver ionised water (concentration: 5 ppm) produced with the sintering coating method in the sensor part of the pH metre, plaque collected from the oral cavity by one platinum loop was mixed in. Immediately after that, a 5% sucrose solution (1 g/20 mL) was added and the pH was continuously measured for 30 minutes at 1-minute intervals (A). Similarly, silver ionised water was mixed with 5% sucrose solution in the same way as in (A) at 3 (B), 5 (C), 10 (D) and 15 minutes (E) after plaque contamination. The pH was measured at 1-minute intervals. The pH of the purified water containing no silver ionised water mixed with plaque and sugar solution at the same time was measured and used as a control. Each experiment was conducted three times, and the pH measured every minute was compared as a percentage of the pH at the beginning of the measurement (100%). <strong>Results:</strong> Analysis of variance of the repeated measurements to determine the effect of silver ionised water on the decrease in pH revealed a main effect of silver ionised water and an interaction between time and group [F<sub>(1.302,20.826)</sub> = 39.145, p < 0.01]. Multiple comparisons using Dunnett’s method showed a significant decline in the rate of decrease in pH from B to E as compared with that in the control (p < 0.01). <strong>Conclusion: </strong>Silver ionised water was found to inhibit the acid production in plaque.
文摘One of the most important functions of skins is to protect our bodies from microbes or pollutant sources. Skins containing physical substances serve as a physical barrier which protects our bodies from pathogens. A healthy skin contains a variety of antibacterial substances such as defensin, cathelicidin and psoriasin. However deep and wide burns cause the skin to lose its original functions, so our skins are exposed to various danger factors. For the burn patients, human alloskin graft serves as a very important temporary biological wound dressing. It protects the wound before autograft procedure, forms revascularization and granulation tissues and protects the wound from an invasion of microbes. This study was conducted with the aim to analyze the antimicrobial effect of cryopreserved allograft (CPA) and glycerol-preserved allograft (GPA) which was a type of allograft widely used for burn patients, and measure the difference in comparison with the fresh skin before processing it. The most common contaminants found in burn patients such as S. aureus, P. aeruginosa, C. albicans and E. coli, were used for experiment. The antimicrobial effect against S. aureus and E. coli was observed in fresh skin and some CPA. In some clinical cases, infection is frequently observed in the wounds treated with allograft, indicating the allograft completely block every kind of microbes. To prevent the infection, it is required to use antibiotics and manage wounds thoroughly.
文摘Antimicrobial and photocatalytic effect of silicate and silicone paints were tested. Silicate paints are based on water styrene-acrylic dispersion with mineral binder into form of potassium water glass. Silicone paints are based on water acrylic dispersion with silicone resin emulsion. Silicate and silicone paints were formulated with photocatalytic active nanooxides TiO2 and ZnO. Photocatalytic efficiency of coatings was measured as an absorbance change of organic dye Orange II solution at a wavelength of 485 nm. Antimicrobial properties of coatings were tested using agar plate methods. As test microorganisms Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Penicillium chrysogenum and Aspergillus niger suspension (density 10^6 cells/mL) were used. The inhibition effect of tested coatings and inhibitory zones were evaluated after incubation. Coatings containing nanoparticles of titanium dioxide and zinc oxide showed antimicrobial activity against the test microorganisms. Whereas coating with zinc oxide nanoparticles successfully inhibited the growth of both bacteria and fungi, the photocatalytic nanoparticles of titanium dioxide inhibited bacteria but not fungi (weak inhibition was observed).
基金supported by the Special Fund for Agro-scientific Research in the Public Interest(No.201403047)Science Technology Department of Zhejiang Province(2015C02022)
文摘Background: A series of modified montmorillonites(Mt) including zinc-loaded Mt(Zn-Mt), copper-loaded Mt(Cu-Mt), copper/zinc-loaded Mt with different Cu/Zn ratio(Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3) were prepared by an ion-exchange reaction, and characterized using X-ray diffraction(XRD), fourier transformed infrared spectroscopy(FTIR) and transmission electron microscopy(TEM). The specific surface areas, antimicrobial activity and cytotoxicity of the modified Mt were investigated.Results: In the modified Mt, hydrated Cu ions and Zn ions were exchanged in the interlayer space of Mt and the particles were irregular shapes. The results showed that Cu/Zn-Mt enhanced antibacterial and antifungal activity compared with Zn-Mt and Cu-Mt possibly due to the synergistic effect between Cu and Zn. Among the Cu/Zn-Mt with different Cu/Zn raitos, Cu/Zn-Mt with a Cu/Zn ratio of 0.98 or 0.51 showed higher antimicrobial activity against gram-negative bacteria(Escherichia coli), gram-positive bacteria(Staphylococcus aureus), fungi(Candida albicans).Moreover, the antimicrobial activity of Cu/Zn-Mt was correlated with its specific surface area. Cytotoxicity studies on IPEC-J2 cell showed a slight cytotoxicity of Cu/Zn-Mt.Conclusions: The current data provide clear evidence that in terms of its antimicrobial activity and relatively low toxicity, the Cu/Zn-Mt holds great promise for applications in animal husbandry.
文摘The present work is devoted to the study of antiradical and antimicrobial activities of phenolic compounds extracted from different grapevine varieties grown in the Bekaa plane-Lebanon. The amount of phenolic compounds in selected grape extracts was determined by the Folin-Ciocalteau method. Phenolic composition was specified by high performance liquid chromatography. Free radical scavenging activity was examined by using the (2,2’-diphenyl-1-picrylhy-drazyl) DPPH assay. The potential antimicrobial activity was studied using a new quantitative method developed during this work. This activity was tested against several microbial pathogens, including a Gram-positive strain (Listeria monocytogenes), two Gram-negative strains (Escherichia coli and Salmonella arizonae) and a fungal strain (Candida albicans). According to the results of the present screening study, a great variability in the composition of phenolic com-pounds in red grape extracts was detected. All phenolic compounds extracts, demonstrated important scavenging properties and antimicrobial effect against bacterial and fungal strains. Yet, a different response degree was noticed depending on the tested microorganism and the phenolic composition of grape extracts. Antimicrobial activity was more effective against Gram-positive than Gram-negative and yeast strains. Furthermore, our results highlighted a significant role of synergistic effect between various phenolic compounds in the free radical scavenging and antimicrobial activities.
基金Supported by the Federal Ministry of Education and Research of Germany(BMBF,project CEMOSTOBAS),No.13N12105
文摘AIM To investigate osteoconductive and antimicrobial properties of a titanium-copper-nitride(TiC uN) film and an additional BONIT~? coating on titanium substrates.METHODS For micro-structuring, the surface of titanium test samples was modified by titanium plasma spray(TPS). On the TPS-coated samples, the Ti Cu N layer was deposited by physical vapor deposition. The BONIT~? layer was coated electrochemically. The concentration of copper ions released from TiC uN films was measured by atomic absorption spectrometry. MG-63 osteoblasts on Ti Cu N and BONIT~? were analyzed for cell adhesion, viability and spreading. In parallel, Staphylococcus epidermidis(S. epidermidis) were cultivated on the samples and planktonic and biofilm-bound bacteria were quantified bycounting of the colony-forming units. RESULTS Field emission scanning electron microscopy(FESEM) revealed rough surfaces for TPS and TiC uN and a special crystalline surface structure on TiC uN + BONIT~?. TiC uN released high amounts of copper quickly within 24 h. These release dynamics were accompanied by complete growth inhibition of bacteria and after 2 d, no planktonic or adherent S. epidermidis were found on these samples. On the other hand viability of MG-63 cells was impaired during direct cultivation on the samples within 24 h. However, high cell colonization could be found after a 24 h pre-incubation step in cell culture medium simulating the in vivo dynamics closer. On pre-incubated TiC uN, the osteoblasts span the ridges and demonstrate a flattened, well-spread phenotype. The additional BONIT~?-coating reduced the copper release of the TiC uN layer significantly and showed a positive effect on the initial cell adhesion.CONCLUSION The Ti Cu N-coating inhibits the formation of bacterial biofilms on orthopedic implants by influencing the "race for the surface" to the advantage of osteoblasts.
文摘Objective: To evaluate the antimicrobial, antioxidant, cytotoxicity and anticancer activity of fractions from Jatropha zeyheri roots and to explore the phytochemical profile of the most biologically active fraction.Methods: Fractions from Jatropha zeyheri ethyl acetate extract were investigated for antimicrobial activity against a plethora of pathogenic microorganisms of different origins. The cytotoxicity studies of fractions were evaluated in vitro using tetrazolium-based calorimetric assay against human dermal fibroblast, colon adenocarcinoma(Caco-2), breast cancer(MCF-7) and lung cancer(A547) cell lines. The anti-oxidant activity of fractions was determined in vitro against 2,2-diphenyl-1-picrylhydrazyl(DPPH), 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt(ABTS) and chelation of iron(Fe2+). Gas chromatography mass spectrometry analysis was performed to detect phytochemical constituents in fraction with potent biological activity.Results: Fraction 2 of Jatropha zeyheri roots exhibited the lowest minimum inhibitory concentration of 40 μg/mL against Klebsiella pneumoniae and 80 μg/mL against Candida albicans, Staphylococcus aureus and Mycoplasma hominis. The fractions revealed some varying degrees of cytotoxicity against human dermal fibroblasts yielding LC50 values ranging from 28.96 to 166.52 μg/mL. Fraction 3 exhibited the highest selectivity index value of 2.08 against Klebsiella pneumoniae. Moreover, fraction 2 selectively inhibited the growth of Caco-2 with LC50 of 8.83 μg/mL, compared to other cancerous cell lines. Fraction 2 of Jatropha zeyheri further exhibited IC50 of 19.66, 22.63 and 1.82 μg/mL against DPPH, ABTS and Fe2+, respectively. Gas chromatography mass spectrometry analysis revealed the presence of cyclotetracosane(10.08%), 9-hexacosene(9.40%), hexadecanoic acid(3.90%),(Z)-9-octadecenamide(3.63%), octacosane(2.27%), 11-n-decylheneicosane(2.23%), ethyl vallesiachotamate(2.17%), heneicosanoic acid(2.10%), and octadecanoic acid(2.08%) in fraction 2 of Jatropha zeyheri.Conclusions: These identified compounds, particularly cyclotetracosane(hydrocarbon), may well explain the biological activity of fraction 2 of Jatropha zeyheri, which possesses higher biological activity than other fractions. These compounds can be further investigated for use in treating various bacterial and fungal opportunistic infections associated with HIV-AIDS and related cancers.
基金funded by Universidad Autonoma de Baja California and Instituto Tecnologico de Tuxtla Gutierrez,Mexíco.
文摘In the present study,the green synthesis of potassium nanoparticles(K-NPs)was assessed using aqueous extract of Sideroxylon capiri.The potassium nanoparticles were analyzed by UV-visible spectroscopic techniques,X-ray spectrometers of energy dispersive(SEM-EDS)and dynamic light scattering.The results showed high values at 3.5 keV confirming the formation of potassium nanoparticles and the SEM analysis showed an agglomerated particles size between 360 to 200 nm with a spherical morphology.The K-NPs showed an effective antibacterial activity against the test organisms mainly with Bacillus cereus,Enterobacter aerogenes,Fusarium solani and Botrytis cinerea.However further studies about nanotoxicity of K-NPs are needed to confirm their potential in the control of the pathogen microorganisms under field conditions.
基金supported by National Key Basic Research Program of China(2013CB127300)Natural Science Foundation of China(31430082)
文摘Backgroud: This study aimed to determine the effects of early antibiotic intervention(EAI) on subsequent blood parameters, apparent nutrient digestibility, and fecal fermentation profile in pigs with different dietary crude protein(CP) levels. Eighteen litters of piglets(total 212) were randomly allocated to 2 groups and were fed a creep feed diet with or without in-feed antibiotics(olaquindox, oxytetracycline calcium and kitasamycin) from postnatal d 7 to d 42. On d 42, the piglets within the control or antibiotic group were mixed, respectively, and then further randomly assigned to a normal-(20%, 18%, and 14% CP from d 42 to d 77, d 77 to d 120, and d 120 to d 185,respectively) or a low-CP diet(16%, 14%, and 10% CP from d 42 to d 77, d 77 to d 120, and d 120 to d 185,respectively), generating 4 groups. On d 77(short-term) and d 185(long-term), serum and fecal samples were obtained for blood parameters, microbial composition and microbial metabolism analysis.Results: EAI increased(P 〈 0.05) albumin and glucose concentrations in low-CP diet on d 77, and increased(P 〈 0.05) urea concentration in normal-CP diet. On d 185, EAI increased(P 〈 0.05) globulin concentration in normal-CP diets, but decreased glucose concentration. For nutrient digestibility, EAI increased(P 〈 0.05)digestibility of CP on d 77. For fecal microbiota, the EAI as well as low-CP diet decreased(P 〈 0.05) E. coli count on d 77. For fecal metabolites, on d 77, EAI decreased(P 〈 0.05) total amines concentration but increased skatole concentration in low-CP diet. On d 185, the EAI increased(P 〈 0.05) putrescine and total amines concentrations in low-CP diets but reduced(P 〈 0.05) in the normal-CP diets. The low-CP diet decreased the concentrations of these compounds.Conclusions: Collectively, these results indicate that EAI has short-term effects on the blood parameters and fecal microbial fermentation profile. The effects of EAI varied between CP levels, which was characterized by the significant alteration of glucose and putrescine concentration.
文摘Objective:This study has been done to evaluate the interaction between water extracts of Psidium guajava, Rosmarinus officinalis,Salvia fruticosa,Majorana syriaca,Ocimum basilucum,Syzygium aromaticum,Laurus nobilis,and Rosa damascena alone and then synergy testing of these extracts with known antimicrobial agents including oxytetracycline HCl,gentamicin sulfate,penicillin G,cephalexin and enrofloxacin.This study was conducted against five S.aureus isolates;one is Methicillin -resistant Staphylococcus aureus(MRSA) and 4 Methicillin - sensitive Staphylococcus aureus(MSSA).Methods:Evaluation of the interaction between plant extracts and different antimicrobial agents has been done using well - diffusion and microdilution methods. Results:The results of the conducted experiments using well - diffusion method demonstrate that these plants showed in vitro interactions between antimicrobial agents and plant extracts were additive,while using microdilution method showed synergistic effects with significant reduction in the MICs of the test antibiotics against these strains of S.aureus.This change in MIC was noticed in all plant extracts against test antibiotics including these plants showed weak antibacterial activity by well diffusion method.Synergism effect was occurred in both sensitive and resistant strains but the magnitude of minimum fold reduction of inhibitory concentration in resistant strains especially MRSA strain was higher than the sensitive strains.Coclusion:This study probably suggests the possibility of concurrent use of these antimicrobial drugs and plant extracts in combination in treating infections caused by S.aureus strains or at least the concomitant administration may not impair the antimicrobial activity of these antibiotics.
文摘Background: Laboratory personnel is at risk of biological contamination leading to laboratory-acquired infections (LAIs). The use of disinfection products is essential in the prevention of these infections. This work aimed to evaluate the effectiveness of antimicrobial agents used in disinfection in bacteriology laboratories in Togo. Methods: This was a cross-sectional study conducted from June to December 2021 in all bacteriology laboratories in Togo. Swabs taken before and after disinfection of surfaces and staff hands were immediately plated on agar media. Counting and identification of isolated colonies were done after 24 hours of incubation. The ANOVA test was used to compare calculated means, prevalence ratio (PR) and 95% confidence intervals (CI) to compare bacterial frequencies. Results: A total of 393 samples were taken, of which 41.2% were from hands. Before disinfection, surfaces were more contaminated than hands with respectively 40.4% and 29.6% (PR = 1.3;CI 95% = [0.9 - 1.9]). After surface disinfection with 0.5% of chlorine solution, bacterial elimination was total, but partial on hands washed with soap, with residual contamination of 3.7%. A total of 108 strains were isolated before disinfection of which Klebsiella spp. 38.9% and Staphylococcus spp. 25.0%;after disinfection 4 strains were isolated of which: Staphylococcus spp. 75.0% and Klebsiella spp. 25.0%. Conclusion: Surface disinfection was more effective than hand washing with soap and water. We recommend proper hand washing.
基金Supported by Science and Technology Planning Project of Qinhuangdao City(201602A185)
文摘[Objectives] This study was conducted to determine in-vitro antibacterial effect of 58 Chinese herbs on Staphylococcus aureus,and screen single Chinese herbs with better in-vitro antibacterial effect for formulation of prescription. [Methods]Effective components in Chinese herbs were extracted with water,and inhibition zone diameters and minimal inhibitory concentrations of the 58 Chinese herbs against S. aureus were determined by agar plate punching method and micro two-fold method,respectively. [Results] Twenty two kinds of Chinese herbs including Terminalia chebula Retz.,Anemarrhena asphodeloides Bunge.,Prunella vulgaris L,Rheum palmatum L. and Mosla chinensis Maxim. had better antibacterial effect,among which T. chebula Retz.,A. asphodeloides Bunge.,P. vulgaris L,R. palmatum L. and C. sappan Linn showed the best antibacterial effect,with average inhibition zone over 20 mm and MIC lower than 15. 6 mg/ml.[Conclusions]Traditional Chinese herbs have certain antibacterial effect,and this study will provide important theoretical reference for clinical medication and development of prescription.