Antibacterial Effect of Nano-scale TiO_2 on Parasitic Bacterium of Nanfeng Citrus in Storage Period

[Objective] The aim was to observe the antibacterial effect of nano-scale Titanium dioxide on parasitic bacterium of Nanfeng Citrus in storage period.[Method] Nano-scale Titanium dioxide was prepared by dibutyl phthalate through sol-gel method under anhydrous conditions,and orthogonal experiment was used to determine optimum conditions for nano-scale Titanium dioxide preparation,and structure characterization of nano-scale Titanium dioxide was carried out by X-Ray diffractometer.Oxford cup method was used to explore inhibition effect of nano-scale Titanium dioxide suspension on the activity of normal parasitic bacterium of Nanfeng Citrus.Simultaneously,the empirical preservation test was carried out.[Result] The average diameter of nano-scale Titanium dioxide powder attained to 14.6 nm,actual average yield could reach 90.83% with RSD（Relative Standard Deviation）of 0.86%.[Conclusion] Nano-scale Titanium dioxide had good antibacterial effect on the parasitic bacterium of Nanfeng Citrus in storage period.

In vitro corrosion resistance and antibacterial properties of layer-by-layer assembled chitosan/poly-L-glutamic acid coating on AZ31 magnesium alloys

Surface functionalization of magnesium(Mg)alloys is desired to obtain the surfaces with both improved corrosion resistance and antibacterial property.A corrosion-resistant and antimicrobial coating was prepared on Mg alloy surface by layer-by-layer(LbL)assembly of chitosan(CHI)and poly-L-glutamic acid(PGA)by electrostatic attraction.The functionalized surfaces of the Mg alloys were characterized by field-emission scanning electron microscopy(FE-SEM),Fourier transform infrared(FT-IR)spectroscopy and electrochemical tests.The bactericidal activity of the samples against Staphylococcus aureus was assessed by the zone of plate-counting method.The obtained coating on the Mg alloy substrates exhibits good corrosion resistance and antibacterial performance.

Antibacterial Effect of Cinnamon Oil Combined with Thyme or Clove Oil

Antibacterial effect of cinnamon oil combined with thyme or clove oil was studied in this paper. Agar dilution method was used to determine the minimum inhibitory concentrations （MICs） of the essential oils （EOs） of cinnamon, thyme, and clove oil against three Gram-positive bacteria （Bacillus subtilis, Bacillus cereus, and Staphylococcus aureus）, and two Gramnegative bacteria （Escherichia coli and Salmonella typhimurium）. The results showed that cinnamon was a promising antibacterial substance with MIC ranged from 0.1 to 0.4 μL mL^-1 for the five bacterial species. Agar dilution checkerboard method was used to test the combined antibacterial effect of cinnamon oil with thyme or clove oil. Combination of cinnamon and thyme oil showed an additive effect against all selected bacteria, and combination of cinnamon and clove oil displayed an additive effect against B. subtilis, B. cereus, S. aureus, and an indifferent effect against E. coli and S. typhimurium. Furthermore, gas chromatography-mass spectrometry （GC-MS） measurement was used to analyze the components of the EOs, and the main components of cinnamon, thyme, and clove were cinnamaldehyde, thymol, carvacrol and p-cymene, and eugenol, respectively.

Antibacterial Effects of Nanometallic Materials in Genetic Transformation of Anthurium by Agrobacterium-mediated Method

[Objective] This study was conducted to investigate the application of nanometallic materials in inhibiting Agrobacteriurn contamination in genetic transformation of Anthurium. [Method] Different nanometallic materials were added into Agrobacterium medium and Anthurium callus medium, to investigate the effects of their effects on Agrobacterium growth, callus growth and differentiation, and Agrobacterium contamination. [Result] Among the 4 nanometallic materials, NanoAg-2 showed a significant inhibitory effect on the growth of Agrobacterium, with a minimal inhibitory concentration of 25 mg/L. Even for the Anthurium calli or transgenic material contaminated by the Agrobacterium, a good antibacterial effect could be achieved after treating with 25 mg/L NanoAg-2 for 1 d with oscillation, the antibacterial rate reached 100%, and the Anthurium calli could grow and differentiate normally. [Conclusioa] NanoAg-2 could effectively inhibit Agrobacterium contamination, and its an- tibacterial effect is significantly better than cephalosporin and carbenicillin.

Antibacterial Effect of the Conducting Polyaniline

Excellent antibacterial performance of polyaniline （PAni） against Escherichia coli and Gram-positive Staphylococcus aureus microorganisms has been demonstrated under both dark and visible light conditions. The electrostatic adherence between the PAni molecules and the bacteria may play a very important role for the antibacterial reaction of the PAni. As a result of our investigation, conducting PAni and its composites/blends are believed to be useful as a new type of antibacterial agent, self-clean as well as multifunctional material for improving the human health and living environment.

Antibacterial effect and physicochemical properties of essential oil of Zataria multiflora Boiss

ObjectiveTo evaluate the antibacterial effect and physicochemical properties of essential oil of Zataria multiflora Boiss.MethodsAntibacterial activity of essential oil of Zataria multiflora Boiss was assessed by agar disc diffusion and minimal inhibitory concentration(MIC) was tested by E test.ResultsThe essential oil of Zataria multiflora Boiss was effective on pathogenic bacteria particularly Staphylococcus aureus (S. aureus). The MIC values of the target cultures ranged from 0.39 mg/mL to 1.56 mg/mL. The physicochemical properties like effects of pH, temperature, detergents, and enzymes on the activity of essential oil from Zataria multiflora Boiss were also determined. The essential oil was quite stable to temperature as tested against S. aureus and Escherichia coli (E. coli). The essential oil was very stable over a wide range of pH. The antibacterial activity of essential oil was insensitive to various protein-denaturing detergents (Such as Tween 80, Tween 20, Triton 100, etc.) and enzymes (namely proteinase K, trypsin, lipase, and lysosyme).ConclusionsA potential use of the essential oil from Zataria multiflora Boiss is suggested. More studies including further purification, mass spectra, nuclear magnetic resonance (NMR) and evaluation of toxicity are needed for confirmation of this suggestion.

Thermodynamic Study on Antibacterial Effect of Different Extracts from Radix Isatis

Objective： To study and analyze the antibacterial effects of different extracts from Radix Isatis. Methods： Staphylococcus aureus was used as the studied object in the experiment. Antibacterial effects of extracts from Radix Isatis were observed by thermocalrimetry on Staphylococcus aureus, together with common pharmacological experiments. Results： The total extract, ethyl acetate （EtOAc） extract, n-butylalcohol （nBuOH） extract, chloroform （CHCl3） extract and petroleum （P. E.） extract had antiviral effects to some extent while the residue after extracting had no antibacterial activity. The potency of antiviral activity among them was as follows： nBuOH extract 〉 EtOAc extract 〉 CHCl3 extract〉 total extract 〉P. E. extract. Conclusion： The antibacteriall effects of Radix Isatis were not limited to any active portion, showing that Radix Isatis exerts its antibacterial effects by cooperation of different active fractions in varied ways.

Antibacterial and Antioxidant Effects of Three Chlorogenic Acid Extracts

[Objectives] To study the antibacterial and antioxidant effects of chlorogenic acid extracts of Gynura procumbens,Lonicera japonica,and Eucommia ulmoides leaves,and provide a reference for their usage as natural food preservatives and antioxidants. [Methods]The disc diffusion method was applied to study the antibacterial activity of chlorogenic acid extracts of G. procumbens,L. japonica,and E. ulmoides leaves against several common pathogens. In the antioxidant effects,study was carried out on the anti-lipid peroxidation,reducing capacity,and DPPH free radical scavenging capacity of chlorogenic acid extracts of G. procumbens,L. japonica,and E. ulmoides leaves,respectively.[Results]Three chlorogenic acid extracts had strong inhibitory effects on bacteria,especially the inhibition on Staphylococcus aureus. At the concentration of 100 mg/m L,the bacteriostatic ring of chlorogenic acid extracts of G. procumbens,L. japonica,and E. ulmoides leaves reached 21. 4,23. 6 and 24. 7 mm respectively. Besides,these chlorogenic acid extracts had significant inhibitory effect on Escherichia coli and Salmonella,but the inhibitory effect on the yeast was not obvious; the antibacterial intensity of antibacterial compounds was chlorogenic acid extracts of E. ulmoides > chlorogenic acid extracts of L. japonica > chlorogenic acid extracts of G. procumbens. Among these three chlorogenic acid extracts,the chlorogenic acid extracts of E. ulmoides had higher anti-lipid peroxidation,reducing capacity,and DPPH free radical scavenging capacity than other two chlorogenic acid extracts. [Conclusions] This paper reveals that among chlorogenic acid extracts of G. procumbens,L. japonica,and E. ulmoides leaves,the chlorogenic acid extracts of E. ulmoides leaves have a stronger antibacterial activity and antioxidant activity.

Antibacterial Effect of the Essential Oils Extracted From Ruta chalepensis L. and Ruta montana （L.） L.

Ruta genus is a member of the family Rutaceae that has been cultivated widely in many regions of the world because of its medicinal properties. In Tessala Mountain （Sidi Bel Abbes Country, North-Western of Algeria）, the Ruta genus commonly known by ＂fidjel＂ is represented by two species： Ruta Chalepensis L. and Ruta Montana （L.） L. frequently used by local population in a traditional treatment. The water-distilled essential oils from this species yielded 7.23% and 6.104% for Ruta chalepensis L. and Ruta montana （L.） L. respectively. The essential oil of Ruta montana （L.） L. showed a strong antibacterial activity against all bacterial strains tested （Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Mycobacterium kansasii ATCC ! 2478 and Mycobacterium vaccae ATCC 1548314） compared to Ruta chalepensis L. oils which have a moderate effect only on Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853. Therefor, the antibacterial properties of the essential oils of Ruta Chalepensis L. and Ruta Montana （L.） L. are now well established through this study and therefore could justify their future uses in the treatment of nosocomial infections.

The Antibacterial Effect of Silver-carrying B_2O_3-SiO_2-Na_2O Glass Material

The antibacterial effect of carrying silver B_2O_3-SiO_2-Na_2O glass material was studied by means of antibacterial ring, nephelometery,MIC value, thin film attachment and microcalorimetry, respectively. The experimental results of five kinds of antibacterial test methods are almost identical and can verify that carrying silver B_2O_3-SiO_2-Na_2O glass material exerts an excellent antibacterial performance. Antibacterial ring and nephelometery are simple, quick, but the precision is restrictive. MIC value, thin film attachment method and microcalorimetry can quantitatively compare the antibacterial effects of the antibacterial glass material.Compared with the traditional microbe test methods, the microcalorimetry can analyze the inhibiting effect of the cell's growth and metabolism on the antibacterial glass material by monitoring the thermal effect continuously and automatically.

Experimental Study on the Antibacterial Effect of Origanum Volatile Oilon Dysentery Bacilli In Vivo and In Vitro

To observe the germistatic and germicidal effects of origanum volatile oil (OVI) on the dysentery bacteria, the abdominal cavity of mice was infected with Shigella sonne (Sh. sonnei) and Shigella flexneri (Sh. flexneri) F 2a. After OVI was given to the mice via gastric lavage, the effects of OVI on the infected mice were observed. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) for dysentery bacteria were determined in vitro. The results showed that origanum volatile oil showed obvious protective effect on mice infected with Sh. sonnei and Sh. flexneri F 2a. and it had germistatic and germicidal effects on dysentry bacteria. We are led to conclude that origanum volatile oil is an effective medicine against the infection of dysentery bacteria.

Study on Antibacterial Effects of Purple, Yellow and White-skinned Onions

Onion(Allium cepa L.)is a common biennial herb,and contains allicin compounds which can kill harmful microorganism.The antibacterial effects of raw and mature onion juice of purple,yellow and white-skinned onions at different concentrations on Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were studied.There were differences among the antibacterial effects of raw and mature onion juice of purple,yellow and white-skinned onions at different concentrations.What was more,the antibacterial effects of raw onion juice were better than those of the mature one.The antibacterial effects of high concentration onion juice were better than those of the low one.The content of the total flavonoids in raw purple onion was higher than that in mature onion,and reached extremely significant levels in 50%,75%and 100%,respectively.Through comparison,it was found that onion juice of purple-skinned had the best suppression effects on S.aureus(gram-positive bacterium)and E.coli(gram-negative bacterium),and gram-positive bacterium had better suppression effects than gram-negative bacterium.It wound provide the basis about bioactive function and antibacterial drugs.

In Vitro Antibacterial Effect of Effective Microorganisms( EM) on Aeromonas hydrophila

In order to understand in vitro antibacterial effect of antibiotics and EM on Aeromonas hydrophila,14 isolates of A. hydrophila were isolated from diseased fish and aquaculture in the study. PCR amplification results of aerolysin gene( Aero gene) of isolates indicated that 7 out of 14 isolates were pathogenic A.hydrophila. In vitro antibacterial test indicated that 14 isolates were resistance to penicillin G,ampicillin,cephradine,cefazolin,tetracycline,terimethoprim,lincomycin and cephalexin,but showed high sensitivity to cefotaxime and furazolidone. In vitro antibacterial effect of EM on 14 isolates of A. hydrophila was positively correlated with concentration,and EM with the concentration greater than 60% had antibacterial effect on 14 isolates.

In-vitro Antibacterial Effect of Hedyotis hedyotidea Ethanol Extract

[Objectives]This study was conducted to investigate the antibacterial effect of the extract from Hedyotis hedyotidea(DC)Merr.[Methods]Through in-vitro antibacterial tests,the antibacterial effects of H.hedyotidea ethanol extract on Escherichia coli,Staphylococcus aureus and Bacillus subtilis were analyzed.[Results]The extract had a low-susceptibility inhibitory effect to the three kinds of bacteria,and the minimal inhibitory concentrations(MICs)corresponding to S.aureus,E.coli and B.subtilis were 200,175 and 150 mg/ml,respectively.The minimal bactericidal concentrations(MBCs)corresponding to E.coli and S.aureus were both 500 mg/ml.[Conclusions]This study provides theoretical support for the wide application of H.hedyotidea.

Study on Antibacterial Effect of Single Chinese Herbs on Staphylococcus aureus

[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.

Study on Antibacterial Efficacy of Plant-Derived Compound Preservative and Its Product Application

Natural antiseptic formulas are increasingly favored by consumers. This article take preservatives compounded from cinnamon, sophora flavescens and other plant extracts as the main research object, evaluated its antibacterial efficacy and application in cosmetics, expect that it can be used in cosmetics to replace conventional chemical preservatives. Research on its antibacterial efficacy through inhibition zone and MIC experiment, and product application research used anti-corrosion challenge and antibacterial rate experiment. The results showed that the plant-derived antiseptic system had a broad antibacterial spectrum, inhibition of 10 different common pathogenic bacteria, and had a very significant inhibitory effect on Gram-positive bacteria and fungi;Among them, the diameter of the antibacterial circle for Bacillus subtilis and Aspergillus niger can reached 31.89 mm and 28.26 mm, while the MIC value was 0.4 mg/mL and 0.8 mg/mL. The spray product with 1.5% addition amount successfully passed the anti-corrosion challenge test and meets the anti-corrosion standard requirements;The 2% added amount of disposable gel product has an inhibitory rate of 51.05% and 70.74% against Escherichia coli and Staphylococcus aureus within 20 minutes of action. In summary, the plantderived compound preservative has ability to be used in cosmetic preservative systems.

Antimicrobial Activity of Some Commercial Toothpastes and Antibiotics on Two Oral Pathogenic Bacteria—An in-Vitro Study

Oral health problems such as periodontal diseases, dental caries, and endodontic infections have a significant negative impact on oral health and impose a substantial financial burden on the global population. The prevalence of these issues is increasing due to the buildup of bacterial plaque and the growing resistance of bacteria to antimicrobial treatments. The aims of this study to evaluate the anti-bacterial activity of four types of antibiotics (Amoxicillin, Augmentin, Azithromycin and Metronidazole) and four types of toothpastes (Sensodyne, ipana, denta and cariax Gingival Kin) on two oral pathogenic bacteria (Streptococcus mutans and Staphylococcus epidermidis). Bacterial samples of previously isolated Streptococcus mutans and Staphylococcusepidermidis were used as test organisms and the Kirby-Bauer disc diffusion method was employed to assess the antibacterial efficacy of various antibiotics and evaluate the impact of different toothpastes using a filter paper disc agar measurement technique. Each filter disc was saturated with toothpaste solution in a test tube for approximately 30 to 40 seconds, after which they were placed on Mueller-Hinton broth bacterial cultures in petri dishes. These Petri dishes were then incubated at 37°C for 24 hours, and the clear zone’s diameter (inhibition zone in mm) was subsequently measured and the results were recorded. The results demonstrated that Sensodyne toothpaste and Metronidazole antibiotic were ineffective against both types of bacteria, while Augmentin and Amoxicillin were effective by high diameter inhibition zones of growth against S. mutans and Azithromycine against S. epidermidis. Also Ipana, Denta, and Cariax Gingival Kin toothpastes exhibited a moderate effect against the two bacteria. This study suggests that certain antibiotics and toothpastes can effectively inhibit the growth of harmful oral bacteria, but not all of them are effective.

Control Effects of Bacillus subtilis DJ-6 and Pyraclostrobin Alone and in Combination Against Fusarium oxysporum

[Objective] This study was conducted to screen a synergistic biological fungicide complex to control Fusarium wilt, reducing the use of chemical pesticides. [Method] The inhibitory effects of Bacil us subtilis DJ-6 and pyraclostrobin alone or in combination at five ratios against Fusarium oxysporum were detected by mea-suring mycelium growth rate in laboratory tests. The growth promotion and disease control effect of combined or single use of 20% pyraclostrobin and 2 ×1011 cfu/g B. subtilis DJ-6 WP at 1∶1 000, 1∶2 000 and 1∶3 000 dilutions were detected in field trials. [Result] The EC50 values of combined use of B. subtilis DJ-6 and pyra-clostrobin at ratios of 1∶1, 1∶2, 1∶3, 1∶4 and 1∶5 against F. oxysporum were 5.311 5, 4.008 6, 3.570 6, 3.350 9 and 3.218 9 μg/ml, with the synergistic ratios （SR） of 2.28, 1.77, 1.53, 1.64, 1.11, among which the synergetic effect at 1∶1 was the best. The fungicidal activity of pyraclostrobin was greater than that of B. subtilis DJ-6 in laboratory tests. Field trials revealed that al the 1∶1 000, 1∶2 000 and 1∶3 000 dilu-tions of 20% pyraclostrobin·2×1011 cfu/g B. subtilis DJ-6 WP in combination, 1∶1 000 dilution of 1 ×1012 cfu/g B. subtilis DJ-6 WP and 1∶2 000 dilution of 250 g/L pyra-clostrobin EC promoted the growth of strawberry by increasing plant height, leaf petiole, leaf blade area and stem diameter. Among them, the treatments with 1∶1 000 and 1∶2 000 of 20% pyraclostrobin · 2×1011 cfu/g B. subtilis DJ-6 WP in combina-tion had better effects than other treatments. The control effects of al the treat-ments were measured 30 and 80 d after fungicide application. The control effects of 1∶1 000 dilution of 20% pyraclostrobin and 2×1011 cfu/g B. subtilis DJ-6 in combina-tion were up to 100% and 93.11%, which were higher than those in al other treat-ments. The second highest control effects were found in the treatment with 1∶ 2 000 dilution of 20% pyraclostrobin and 2×1011 cfu/g B. subtilis DJ-6 in combination, they were 92.49% and 86.49%, higher than those in other treatments except the 1∶1 000 dilution of 20% pyraclostrobin and 2 ×1011 cfu/g B. subtilis DJ-6 in combination. The control effects of 1∶3 000 dilution of 20% pyraclostrobin and 2×1011 cfu/g B. subtilis DJ-6 in combination were 82.61% and 72.42%, higher than those in treatment with 1∶1 000 dilution of 1×1012 cfu/g B. subtilis DJ-6 WP, but lower than those in treat-ment with 1∶2 000 dilution of 25% pyraclostrobin EC. [Conclusion] Al the results re-vealed that the combination use of 20% pyraclostrobin and 2 ×1011 cfu/g B. subtilis DJ-6 WP at 1∶1 000 to 1∶2 000 dilution had better control effect against strawberry Fusarium wilt.

Antimicrobial effect of alexidine and chlorhexidine against Enterococcus faecalis infection

A previous study demonstrated that alexidine has greater affinity for the major virulence factors of bacteria than chlorhexidine.The aim of this study was to compare the antimicrobial activity of 1%alexidine with that of 2%chlorhexidine using Enterococcus faecalis-infected dentin blocks.Sixty bovine dentin blocks were prepared and randomly divided into six groups of 10 each.E.faecalis was inoculated on 60 dentin blocks using the Luppens apparatus for 24 h and then the dentin blocks were soaked in 2%chlorhexidine or 1%alexidine solutions for 5 and 10 min,respectively.Sterile saline was used as a control.The antimicrobial efficacy was assessed by counting the number of bacteria adhering to the dentin surface and observing the degradation of bacterial shape or membrane rupture under a scanning electron microscope.Significantly fewer bacteria were observed in the 2%chlorhexidine-or 1%alexidine-soaked groups than in the control group(P<0.05).However,there was no significant difference in the number of bacteria adhering to the dentinal surface between the two experimental groups or between the two soaking time groups(P>0.05).Ruptured or antiseptic-attached bacteria were more frequently observed in the 10-min-soaked chlorhexidine and alexidine groups than in the 5-min-soaked chlorhexidine and alexidine groups.In conclusion,10-min soaking with 1%alexidine or 2%chlorhexidine can be effective against E.faecalis infection.

Application of traditional Chinese medicine in treatment of Helicobacter pylori infection

Helicobacter pylori(H.pylori)has a high rate of infection and antibiotic resistance and poses a serious threat to human life.One of the main strategies to overcome drug resistance is to develop new treatment plans.Traditional Chinese medicine(TCM)that is commonly used to treat many diseases in China can reduce drug resistance and increase the eradication rate of H.pylori.In this paper,we review the research progress on TCM in the treatment of H.pylori infection.The mechanism of action of TCM is reviewed and research and applications of TCM in the treatment of H.pylori are demonstrated.Finally,we discuss problems confronting the use of TCM for the treatment of H.pylori infection and propose possible solutions.In addition,the plans of TCM in H.pylori treatment were also screened:Dampness-heat syndrome in the spleen and stomach,deficiency of spleen and stomach,and cold-heat complicated syndrome,and the effective components therein are studied.The antibacterial effect of TCM is relatively slow;for rapid improvement of the treatment effect of refractory H.pylori gastritis,we provide an appropriate treatment regime combining TCM and Western medicine with immune-regulatory and synergistic antibacterial effects.