• Restorative Dentistry and Endodontics
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• v.38 no.1
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• pp.36-42
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• 2013

Objectives: This study evaluated the antibacterial effect and mechanical properties of composite resins ($L_{CR}$, $M_{CR}$, $H_{CR}$) incorporating chitosan with three different molecular weights (L, Low; M, Medium; H, High). Materials and Methods: Streptococcus (S). mutans 100 mL and each chitosan powder were inoculated in sterilized 10 mL Brain-Heart Infusion (BHI) solution, and was centrifuged for 12 hr. Absorbance of the supernatent was measured at $OD_{660}$ to estimate the antibacterial activities of chitosan. After S. mutans was inoculated in the disc shaped chitosan-containing composite resins, the disc was cleansed with BHI and diluted with serial dilution method. S. mutans was spread on Mitis-salivarius bacitracin agar. After then, colony forming unit (CFU) was measured to verify the inhibitory effect on S. mutans biofilm. To ascertain the effect on the mechanical properties of composite resin, 3-point bending and Vickers hardness tests were done after 1 and 3 wk water storage, respectively. Using 2-way analysis of variance (ANOVA) and Scheffe test, statistical analysis was done with 95% significance level. Results: All chitosan powder showed inhibition effect against S. mutans. CFU number in chitosan-containing composite resins was smaller than that of control resin without chitosan. The chitosan containing composite resins did not show any significant difference in flexural strength and Vickers hardness in comparison with the control resin. However, the composite resin, $M_{CR}$ showed a slightly decreased flexural strength and the maximum load than those of control and the other composite resins $H_{CR}$ and $L_{CR}$. Conclusions: $L_{CR}$ and $H_{CR}$ would be recommended as a feasible antibacterial restorative due to its antibacterial nature and mechanical properties.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.3
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• pp.45-51
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• 2013

We developed a new antibacterial material, a non-woven fabric, a sulfur solution, and a new adhesive system to manufacture a new type of functional hybrid corrugated board in previous studies. Based on experimental data, the prototypes of functional hybrid corrugated boards were manufactured and their physical properties and functionalities, including antibacterial property and the freshness maintenance of sweet persimmon, were measured in this study. The functional hybrid corrugated board could be manufactured in the actual process with linerboards, non-woven fabrics, and other materials without any troubles, and was strong enough to be used as a packaging box for agricultural products. The antibacterial property of the hybrid corrugated board showed a value high enough to eliminate bacteria, which could deteriorate the sweet persimmons. Based on appearance observations, weight loss and firmness measurements, the freshness of sweet persimmons in the functional hybrid corrugated board was maintained better than it was in the conventional corrugated board.

• Korean Journal of Medicinal Crop Science
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• v.26 no.2
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• pp.134-140
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• 2018

Background: The extract of Abies holophylla is used as an ingredient in cosmetics. This study assessed the antioxidant and antibacterial activities of the material remaining after the extract is used. Methods and Results: The 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azinobis (3-ethyl benzothiazoline)-6-sulfonic acid (ABTS) radical scavenging abilities were assessed to determined the free radical scavenging activity. The total phenol and flavonoid contents were determined to measure the antioxidant activity. The DPPH and ABTS radical scavenging activities of the resudual extract were higher (95.61 - 99.42% and 74.26 - 77.98% in water extract respectively) than those of the positive control. In 50% EtOH extract, the total phenol content was $389.84mg{\cdot}GAE/m{\ell}$, and the total flavonoid was $0.15mg{\cdot}QE/m{\ell}$. The minimum inhibition concentration degree for antibacterial activity against Staphylococcus aureus was < 8 to < $125{\mu}g/m{\ell}$ compared to that of the positive control in all extracts. The clear zone against S. aureus was found to be $12.2{\pm}3.8mm$. Conclusions: The A. holophylla byproducts were found to have antioxidant and antibacterial activities. Therefore, the materials remaining after the A. holophylla extract is used in cosmetics has potential functional uses.

• The Korea Journal of Herbology
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• v.30 no.5
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• pp.15-21
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• 2015

Objectives : Methicillin-resistantStaphylococcus aureus(MRSA) is a human pathogen. New antibacterial agents are needed to treat MRSA-related infections. This study investigated the antibacterial activity of EtOH 70% extracts ofTonghyeonipal-dan(THD) which prescription is composed of oriental medicine against MRSA.Methods : The antibacterial activity of THD was evaluated against MRSA strains by using the Disc diffusion method, broth microdilution method, Checkerboard dilution test, and Time-kill test; its mechanism of action was investigated by bacteriolysis, detergent or ATPase inhibitors were used.Results : The minimum inhibitory concentration (MIC) of THD is 1,000~2,000 μg/mL against MRSA. In the checkerboard dilution test, fractional inhibitory concentration index (FICI) of THD in combination with antibiotics indicated synergy or partial synergism againstS. aureus. Furthermore, a time-kill assay showed that the growth of the tasted bacteria was considerably inhibited after 24 h of treatment with the combination of THD with selected antibiotics. For measurement of cell membrane permeability, THD 500 μg/mL along with concentration of Triton X-100 (TX) and Tris-(hydroxymethyl) aminomethane (TRIS) were used. In the other hand, N,N-dicyclohexylcarbodimide (DCCD) and Sodium azide (NaN3) were used as an inhibitor of ATPase. TX, TRIS, DCCD and NaN3 cooperation againstS. aureusshowed synergistic action.Conclusions : Accordingly, antimicrobial activity of THD was affected by cell membrane and inhibitor of ATPase were assessed. These results suggest that THD has antibacterial activity, and that THD extract offers great potential as a natural antibiotic against MRSA.

• Korean Journal of Pharmacognosy
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• v.37 no.4 s.147
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• pp.266-271
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• 2006

Sophorae Radix, the dried roots of Sophora flavescens Aiton (Leguminosae), has been used in oriental traditional medicine for treatment of skin and mucosal ulcers, sores, gastrointestinal hemorrhage, diarrhea, inflammation and arrhythmia. Present study was carried out for the gastroprotective effect of trifolirhizin from Sophora flavescens. This reports were evaluated antibacterial activity against Helicobacter pylori and HCl ethanol-induced gastric lesion in rats and showed the significant effectiveness. In pylorus ligated rats, the treatments of trifolirhizin showed decrease in the volume of gastric secretion and acid output. Also we evaluated the antibacterial activity against H. pylori treated with methanol extract and trifolirhizin from Sophora flavescens had a equivalent antibacterial activity with ampicillin against H. pylori at the dose of $100{\mu}g/mL$. It may be regarded that the antigastritic effects and antibacterial activity of trifolirhizin from Sophora flavescens are originated from reduction of total acid output identified by gastric secretion reduce, free radical scavenging effects and the antibacterial activity against H. pylori.

• Microbiology and Biotechnology Letters
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• v.36 no.1
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• pp.82-85
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• 2008

Hyungbangjihwang-Tang (HT), an Oriental herbal formula, has been known to play a role which helps to recover vigor of human in the Orient. In this study, antibacterial substance (HTI) was purified from the ethyl-acetate extracts of HT by using $SiO_2$ column chromatography and HPLC, and the antibacterial effects of HTI were investigated. By using the CLSI broth micro-dilution assay, the activity of HTI was evaluated against human pathogenic Gram-positive and Gram-negative bacterial strains including the clinical isolates of methicillin-resistant Staphylococcus aureus. The results demonstrated that HTI showed broad spectrum antibacterial activities against all bacterial strains tested. In conclusion, HTI is an interesting new molecule for its potential in anti-infective drug discovery and for future studies on activity-structure relationship through analysis of its chemical structure.

• Microbiology and Biotechnology Letters
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• v.31 no.2
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• pp.191-196
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• 2003

This study was carried out to investigate the isolation, identification, and antibacterial activity of lactic acid bacteria related to kimchi fermentation. Diluted kimchi soup was plated on the MRS agar media with CaCO$_3$ and incubated at $25^{\circ}C$ for 2 days. A total of 27 strains of lactic acid bacteria from various indigenous, spontaneously fermented vegetables (kimchi) were isolated. Combined methods of Bergey's manual of systematic bacteriology, BPB media analysis and 16S rDNA sequence analysis were applied for identification, however, their results did not coincide in several cases. Isolated lactic acid bacteria could be classified by the 16S rDNA sequence analysis as Leuconostoc mesenteriodes, Leu. carnosum, Lactobacillus curvatus, Lac. pentosus, Weisselia kimchi, W. cibaria, and Pediococcus pentosaceus. Leu. carnosum has not been reported in kimchi lactic acid bacteria. In addition, antibacterial activities of the isolates were tested with Bacillus subtilis, Escherichia coli, Salmonella enteritidis, S. paratyphica, S. typhi, Staphylococcus aureus, Shigella boydii, and S. sonnei. Some of isolates showed significant antibacterial activities to those pathogens.

• The Korean Journal of Food And Nutrition
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• v.22 no.3
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• pp.367-376
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• 2009

This study aimed to determine the antioxidant and antibacterial effects of solvent extracts from Scutellaria baicalensis. The S. baicalensis was successively extracted with 5 kinds of solvents. The obtained samples were as follows; hexan fraction (IPK-1), chloroform fraction(IPK-2), ethyl acetate fraction(IPK-3), butanol fraction(IPK-4), and water fraction(IPK-5). These extracts were determined to process antibacterial effects using a paper disc method against 18 species of human pathogenic bacteria, antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl(DPPH) method and inhibiting ability of linoleic acid autoxidation. Extracts of S. baicalensis has shown selective antibacterial effects on various strains of bacteria. Ethyl acetate fraction(IPK-3) showed the highest antimicrobial activity against selective bacteria, such as Staphylococcus aureus 285, S. aureus 503. In antioxidant activity test, free radical scavenger activity of IPK-3 fraction was 92% compared with BHA at the same concentration, while lipid peroxidation inhibition was 48%. These results suggest that IPK-3 fraction of S. baicalensis could be suitable in development of antimicrobial and antioxidant agents.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.10
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• pp.583-589
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• 2009

Activated carbon has long been used in purification processes for indoor air quality. However, the bioaerosol removal by activated carbon is not often sufficient to be used in an air control devise. In order to overcome these problems, silver nano-particles have been proposed as an antibacterial agent on the surface of activated carbon. Silver or silver ions have been known for antimicrobial activities. In this study, bioaerosol generated by using an Escherichia coli culture was introduced to a lab-scale column packed with activated carbon (AC) and silver nano-particles attached to activated carbon (Ag-AC). E. coli was almost completely removed in the Ag-AC column, whereas bioaerosol penetrated through the AC column. To determine the antibacterial effect of different filter materials in a full-scale air-handling system, another experiment was conducted using a wind tunnel equipped with a heat exchanger and three filter materials including commercial fabric, AC and Ag-AC. It was found that E. coli proliferated on the surface of the heat exchanger after 5 days, which dramatically increased bioaerosol counts in the effluent air stream. The fabric filter could not control the increased bioaerosol and most of the E. coli penetrated the filter. The bacterial removal efficiency was found to be approximately 45% in the AC filter, while the antibacterial efficiency increased to 70% using the Ag-AC filter. Consequently, the Ag-AC filter can be an effective method to control bioaerosol and improve indoor air quality.

• Journal of Korean society of Dental Hygiene
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• v.12 no.3
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• pp.631-640
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• 2012

Objectives : This study mean to confirm the antibacterial activity of a garlic extract widely culturing in our region and was to determine the effect of dentifrice containing 0.1% extracts of garlic on dental plaque and gingivitis in a double blind and clinical studies in 50 healthy adults aged from 20 to 22 years who provided a consent for their participation. Methods : The antibacterial activity was evaluated using triple distilled water and the Kirby-Bauer disk diffusion method and the minimal inhibitory concentration(MIC) against various pathogens for periodontal disease, such as P. gingivalis 381(ATCC33277), was estimated. The experimental groups classified according to the concentration of garlic extract used: 10,000ppm(A), 5,000ppm(B), 2,500ppm(C), 1,000ppm(D). Oral examination of subjects was performed through clinical periods and on day of baseline, 6, 12, 19, 25 days plaque index and gingival index were scored by Turesky' modified index and Loe & Silness index. After 12, 19, 25 days use of their respective dentifrices, statistically decreases of plaque index, gingival index were shown in both the experimental and the control group, respectively. Results : There was significant antibacterial activity in the "2,500ppm(C)" group against P. gingivalis 381. Experimental group exhibited significantly the lower plaque levels and the higher levels of gingival health by the use of the dentifrices contained extract of garlic from 6 days compare with control group(p<0.05). The degree of decrease was more significant on gingivitis level of the experimental group than the control group(p<0.05). Conclusions : This findings indicated that the oral products containing a garlic extract is effective in preventing and treating periodontal diseases, and has potential value in inhibiting periopathogens.