• KSBB Journal
• /
• v.4 no.2
• /
• pp.94-98
• /
• 1989

In vitro attachment experiments of bacteria to surface of host plant cell were carried out using C14 labeled cells of A. rhizogenes strain A4 and carrot protoplasts isolated from suspension culture of cells. Protoplasts were cocultivated with A. rhizogenes at various times after their isolation. Attachment kinetics showed that adherence of bacteria to protoplasts attained a maximum level within 120mins of co-cultivation. Maximum attachment occured at pH 6.0 and 24-35$^{\circ}C$. Bacterial attachment was observed at botg carrot cells with and without primary cell wall. The inhibition of transformation on the carrot root discs by A. rhizogenes was observed when non-related strain and heat inactivated bacterial strain cells were pretreated.

• Korean Journal of Organic Agriculture
• /
• v.14 no.4
• /
• pp.399-410
• /
• 2006

This study was carried out to identity the effects of antifungal bacteria isolated from the soil grown kiwi fruit plants on the growth inhibition of Botrytis cinerea causing gray mold in kiwi fruit plants in the southern districts of Jeonnam. Two hundred and fifty antagonistic microorganisms were isolated and examined into the antifungal activity against Botrytis cinerea. We screened and isolated four bacterial strains which strongly inhibited Botrytis cinerea from the soil grown kiwi fruit plants. And the best antifungal bacterial strain which called CHO 163 was finally selected. Antagonistic microorganism CHO 163 was identified to be the genus Bacillus sp. based on the morphological and biochemical characterization. Bacillus sp. CHO 163 showed 86.9% of antifungal activity against Botrytis cinerea. By the bacterialization of culture broth and heated filtrates of culture broth, Bacillus sp. CHO 163 showed almost all of antagonistic activity against Botrytis cinerea. And we also confirmed that in vitro the treatment of Bacillus sp. CHO 163 cultured by SD+B+P broth efficiently controled the growth of Botrytis cinerea causing gray mold in kiwi fruit plants.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.29 no.4
• /
• pp.618-624
• /
• 2002

Effect of the roasted barley tea in commercial markets on the adherence to the saliva-coated hydroxyapatite(HA) beads and the cell surface hydrophobicity of Streptococcus mutans and Streptococcus sobrinus as cariogenic microorganism was examined in vitro. Adherence activity and hydrophobicity in bacteria tested in all the barley tea samples decreased and the values were different according to the type of tea and the type of treatment. The inhibition of bacterial adsorption to HA beads suggest that barley tea active molecules as catechins and melanoidins may adsorb to a host surface, preventing the tooth receptor from interacting with any bacterial adhesions. The obtained results showed that the barley tea may inhibit bacterial adherence, the first step of the pathogenesis of dental caries in which these microorganism are involved.

• Food Science of Animal Resources
• /
• v.37 no.4
• /
• pp.502-510
• /
• 2017

This study investigated bacterial growth-inhibitory effect of 69 therapeutic herbal plants extracts on 9 bacterial strains using a disc diffusion assay. Especially, the antimicrobial activity of Psoraleae semen, which showed different activity on pathogenic Gram-positive and Gram-negative bacteria, was evaluated by MIC (minimal inhibition concentration) and biofilm formation assay. The effect of Psoraleae semen extract on bacterial cell membranes was examined by measurement of protein leakage (optical density at 280 nm) and scanning electron microscope (SEM). No clear zone was formed on discs containing Gram-negative bacteria, but Gram-positive bacteria exhibited clear zones. The MICs of Psoraleae semen extract were $8{\mu}g/mL$ for Streptococcus mutans, and $16{\mu}g/mL$ for Enterococci and Staphylococcus aureus. In addition, biofilm formation was inhibited at concentration $8-16{\mu}g/mL$. Protein leakage values and SEM images revealed that cell membranes of Gram-positive bacteria were impaired following exposure to the extract. Further, the extract inhibited the growth of Listeria monocytogenes in sausages. These results indicate that Psoraleae semen extract could be utilized as a natural antimicrobial agent against Gram-positive bacteria.

• The Plant Pathology Journal
• /
• v.32 no.4
• /
• pp.311-320
• /
• 2016

Xanthomonas axonopodis pv. glycines (Xag) is a necrotrophic bacterial pathogen of the soybean that causes bacterial pustules and is a nonhost pathogen of the chili pepper. In the current study, chili pepper fruit wound inoculated in planta with Xag 8ra formed necrotic lesions on the fruit surface and induced several structural and chemical barriers systemically in the fruit tissue. The initial defense response included programmed cell death of necrotizing and necrotized cells, which was characterized by nuclear DNA cleavage, as detected by TUNEL-confocal laser scanning microscopy (CLSM), and phosphatidylserine exposure on cell walls distal to the infection site, as detected by Annexin V FLUOS-CLSM. These two responses may facilitate cell killing and enhance transportation of cell wall materials used for cell wall thickening, respectively. The cells beneath the necrotic tissue were enlarged and divided to form periclinal cell walls, resulting in extensive formation of several parallel boundary layers at the later stages of infection, accompanying the deposition of wall fortification materials for strengthening structural defenses. These results suggest that nonhost resistance of chili pepper fruit against the nonhost necrotrophic pathogen Xag 8ra is activated systematically from the initial infection until termination of the infection cycle, resulting in complete inhibition of bacterial pathogenesis by utilizing organspecific in situ physiological events governed by the expression of genes in the plant fruit organ.

• The Plant Pathology Journal
• /
• v.29 no.1
• /
• pp.42-51
• /
• 2013

One of the most important limiting factors for the production of the grafted cactus in Korea is the qualitative and quantitative yield loss derived from stem rots especially caused by Bipolaris cactivora. This study is aimed to develop microbial control agents useful for the control of the bipolaris stem rot. Two bacteria (GA1-23 and GA4-4) selected out of 943 microbial isolates because of their strong antibiotic activity against B. cactivora were identified as Bacillus subtilis and B. amyloliquefaciens, respectively, by the cultural characteristics, Biolog program and 16S rRNA sequencing analyses. Both bacterial isolates significantly inhibited the conidial germination and mycelial growth of the pathogen with no significant difference between the two, of which the inhibitory efficacies varied depending on the cultural conditions such as temperature, nutritional compositions and concentrations. Light and electron microscopy of the pathogen treated with the bacterial isolates showed the inhibition of spore germination with initial malformation of germ tubes and later formation of circle-like vesicles with no hyphal growth and hyphal disruption sometimes accompanied by hyphal swellings and shrinkages adjacent to the bacteria, suggesting their antibiotic mode of antagonistic activity. Control efficacy of B. subtilis GA1-23 and B. amyloliquefaciens GA4-4 on the cactus stem rot were not as high as but comparable to that of fungicide difenoconazole when they were treated simultaneously at the time of pathogen inoculation. All of these results suggest the two bacterial isolates have a good potential to be developed as biocontrol agents for the bipolaris stem rot of the grafted cactus.

• Restorative Dentistry and Endodontics
• /
• v.22 no.1
• /
• pp.170-180
• /
• 1997

Cariogenicity of the bacteria is attributed to their binding capacity to the teeth. Bacterial attachment to oral surfaces is an essential step for colonization and subsequently infection. Therefore, it is conceivable that caries prevention can be achieved fundamentally by inhibition of bacterial attachment. The rationale for caries prevention through the use of sugar substitutes or limited use of sugar has been revealed. Among many sugar substitutes, xylitol has been shown to exhibit the most profound cariostatic effect, inhibiting glucose metabolism and possibly binding of mutans streptococci. The purpose of this study was to examine the effect of xylitol on binding of different species of oral bacteria. The effect of xylitol on binding of [$^3H$]-labeled oral bacteria to hydroxyapatite coated with human saliva(SHA) as a model for the pellicle-coated tooth surfaces was investigated. The strains of oral bacteria used in this study were A. viscosus T14V, A. viscosus WVU627, P. gingivaiis 2561, P. gingivalis A7Al-28, S. gordonii G9B, S. gordonii Challis, S. sobrinus 6715, S. mutans UA101, S. mutans KPSK -2, S. mutans T8, and S. mutans UA130. The obtained results were as follows: 1. P. gingivalis A7 Al-28, S. mutans UA130, S. mutans T8 grown with xylitol showed greater binding to SHA than the organism grown without xylitol. Among these, S. mutans T8 showed the greatest rate of increase in its binding to SHA ; 8-fold increase in its binding with xylitol. 2. S. mutans KPSK -2 grown with xylitol showed 2 times lesser binding to SHA than the organism grown without xylitol. 3. Binding ability of the remaining strains grown with xylitol to SHA was almost same as that of the organisms grown without xylitol. The overall results suggest that use of xylitol in the oral cavity may affect the complex oral bacterial ecosystem.

• Journal of Pharmacopuncture
• /
• v.14 no.1
• /
• pp.79-86
• /
• 2011

Objective : This study was performed to compare anti-inflammation, anti-oxidation and anti-bacterial effects of Cuscutae Semen(CS) extracted with two kinds of solvents, ethanol and distilled water. Methods : Two kinds of CS extractions were prepared 20, 50, 100 ${\mu}l/mg$. The cytotoxicity was measured by MTT assay in Raw 264.7 cell. The anti-inflammation effect was measured by inhibitory efficacy of NO Production in Raw 264.7 cell. The anti-oxidation effect was measured by DPPH Radical scavenging ability in HaCaT cell. The anti-bacterial effect was measured by inhibition zone diameter on Propionibacterium acnes. Results : 1. Two kinds(100 ${\mu}l/mg$) of CS extraction groups had 50% cytotoxicity in Raw 264.7 cell. 2. All of CS extraction groups were not showed significantly inhibitory effect on NO production. 3. All of CS extracted with ethanol only showed dose-dependently significantly scavenging effect of DPPH radicals. 4. Two kinds of CS extractions did not have a inhibitory effect on Propionibactrium acnes. Conclusion : Two kinds(100 ${\mu}l/mg$) of CS extraction groups have 50% cytotoxicity. Two kinds of CS extractions have not the inhibitory effect on NO production and Propionibactrium acnes. CS groups extracted with ethanol only have a significantly scavenging ability of DPPH radicals. This study suggests that CS extracted with ethanol was effective in anti-oxidation.

• Journal of Pharmacopuncture
• /
• v.14 no.1
• /
• pp.71-78
• /
• 2011

Objective : This study was performed to compare anti-inflammation, anti-oxidation and anti-bacterial effects of Ligustici Rhizoma (LR) extracted with two kinds of solvents, ethanol and distilled water. Methods : It is prepared two kinds of LR extracts 20, 50, 100 ${\mu}l/mg$ by first. MTT assay way to measure cytotoxicity is formed in Raw 264.7 cell. The anti-inflammation effect is measured by ability to inhibit production of NO in Raw 264.7 cell. The anti-oxidation effect was measured by DPPH Radical scavenging ability in HaCaT cell. The anti-bacterial effect was measured by inhibition zone diameter on Propionibacterium acnes. Results : 1. LR (20 ${\mu}l/mg$) extracted with ethanol was showed 80% cytotoxicity, LR (50 ${\mu}l/mg$) extracted with ethanol and LR (20, 50 ${\mu}l/mg$) extracted with water were showed 70% cytotoxicity, LR (100 ${\mu}l/mg$) extracted with ethanol and LR (100 ${\mu}l/mg$) extracted with water were showed 60% cytotoxicity in Raw 264.7 cell. 2. LR (100 ${\mu}l/mg$) extracted with ethanol was showed more significantly inhibitory effect on NO production than the water extraction. 3. Two kinds of LR extraction groups did not show significantly scavenging effect of DPPH radicals. 4. Two kinds of LR extractions did not have a inhibitory effect on Propionibactrium acnes. Conclusion : Two kinds of LR extracts have not cytotoxicity, statistically significant ability to scavenge DPPH radicals and effect to inhibit Propionibactrium acnes. LR extracted with ethanol only have a little effect to inhibit NO production. This study proposes that LR extracted with ethanol is more effective in anti-inflammation.

• Physical Therapy Rehabilitation Science
• /
• v.3 no.1
• /
• pp.20-26
• /
• 2014

Objective: The low level lasers currently in the market vary in wavelength, dosage, and frequency. These devices are used with much different clinical pathology. Most notably, some studies claim that wounds heal faster with low level laser therapy due to the fact that bacteria commonly found in wounds are killed by laser light. Systemic and meta-analysis studies found the difficulty of comparison of numerous research studies because of differences in the intensities and frequencies of low level laser treatment (LLLT). The purpose of this study was to determine the effectiveness of LLLT on controlling bacterial growth. Design: Cross-sectional study. Methods: Variables included LLLT dosage and wavelength on 3 bacteria commonly seen in wounds, strains of Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were used on commercially available 5.0-cm agar plates. Blue, green, and red, ultraviolet (UV) and infrared laser light sources were adjusted to either low or high intensity settings. Five Petri dishes at a time were placed directly beneath laser light sources with the exception of UV which was placed six inches below the suspended light and infrared which was placed directly on top of the Petri dish lid. Each group of five Petri dishes was irradiated for 15 minutes. Results: The results showed no effect of any of 9 different LLLT intensities or colors on bacteria growth compared to sham light. Conclusions: At least for claims of bacterial growth inhibition with LLLT, no support for this claim can be found here.