• Natural Product Sciences
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• v.10 no.6
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• pp.325-329
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• 2004

The composition of essential oil from O. javanica was analyzed by gas chromatography-mass spectrometry. Using the broth dilution method and disk diffusion test, anti-microbial activities of the oil fraction and its main components were evaluated against various antibiotic-susceptible and resistant strains of pathogenic microorganisms. As a result of GC-MS analysis, 57 compounds, including ${\alpha}-terpinolene$ (28.1%), dl-limonene (16.0%), ${\gamma}-terpinene$ (10.3%), ${\beta}-pinene$ (9.7%) and ${\alpha}-pinene$ (6.0%) were identified in the essential oil fraction. The essential oil fraction of O. javanica and its main components exhibited significant inhibitory activities, particularly against Candida albicans (antibiotic-susceptible strains) and Streptococcus pneumoniae (antibiotic- susceptible and resistant strains). The main components of the O. javanica oil fraction displayed different patterns of activity against the three tested Candida species as exemplified by the differential minimum inhibiting concentration (MIC) values. The disk diffusion test showed that the activities were dose dependent.

• Journal of the Institute of Convergence Signal Processing
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• v.8 no.4
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• pp.249-254
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• 2007

This paper describes a technique for detecting the boundary of the optic disk in digital image of the retina using inward and outward curve evolution. Optic disk boundary offers medical information about glaucoma progresses. For accurate boundary detection, image inpainting based on PDE removes blood vessels crossing the optic disk. For removing noises and preserving boundary of optic disk in image inpainting process, the anisotropic diffusion filtering is developed. After pre-processing, the optic disk boundary is determined using inward and outward curve evolution. Experimental results show that blurring effect of original region and optic disk boundary is reduced considerably. By the proposed method, we can detect correct disk boundary compare to conventional method.

• Journal of Periodontal and Implant Science
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• v.26 no.1
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• pp.202-215
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• 1996

The purpose of this study was to an in estigate the antibiotic susceptibiliity of Actinoobacillus actinomycetemcomitans isolated from the subgingival plaque to adult periodontitis. Seven bacterial strains were tested for their susceptibility to 10 antimicrobial agents under disk diffusion method and broth dilution methold, Seven patients with deep pocket(6mm) were selected for this study. They had not taken antibiotics for 6 months and no history of dental treatment for 6 months and no history of dental treatment for 6 months before this study. The results were as follows : 1. For the antibiotic disk diffusion method, seven A. actinimycetemcomitans were tested with 10 antimicrobial agents which comprised penicillin, gentamycin, clindamycin, lincomycin, ampicillin, erythromycin, tetracycline, amikacin, chloramphenicol, and vancomycin. The sensitive antibiotics were tetracycline, vancomycin, and chloramphenicol and the resistant antibiotics were clindamycin, and lincomycin. The other antimicrobial agents were less active. 2. From the study of determination on the minimal inhibitory concentration(MIC) by broth dilution method, the MIC of tetracycline to seven strains of the A. actinomycetemcomitans was $0.5-1.0{\mu}g/ml$, that of clindamycin was $32{\mu}g/ml$. These data suggest that tetracycline may be valuable drugs in the elimination of A. actinimycetemcomitans from the patients with adult periodontitis

• Journal of the Society of Cosmetic Scientists of Korea
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• v.25 no.3
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• pp.87-99
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• 1999

Manuka oil named New Zealand’s tea tree oil is oil-soluble and comes firom nature. Manuka oil and its extract $\alpha$-pinene, Oxy’less clear, R-limonene which is one of the component of Citron extracted from Grapefruit seed and Citrex were used to estimate the antimicrobial activity and to improve the capability of antiseptic. Disk diffusion method was used to measure the antimicrobial activity. Escherichia coli which is gram-negative bacteria and Staphylococcus aureus which is gram-positive bacteria were used as strain. The antimicrobial activity of Manuka oil and $\alpha$-pinene for Escherichia coli, Staphylococcus aureus was similar when the concentration of Manuka oil and $\alpha$-pinene are 10u/paper disk. However, antimi-crobial activity of Manuka oil fDr Escherichia coli, Staphylococcus aurem was better than that of $\alpha$-pinene when the concentration of Manuka oil and $\alpha$-pinene was low. Antimicrobial activity of Oxy’less clear is better than that of propyl para hydroxybenzoate(PPHB), R-limonene at all the concentration and is similar to that of $\alpha$-pinene. Antimicrobial activity.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.817-819
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• 2006

8-Quinolinol and other quinolinol derivatives were evaluated with regard to their growth-inhibitory effects against intestinal bacteria, using the paper disk-agar diffusion method. The observed growth responses varied according to the chemicals and dosages used, as well as the bacterial species tested. 8-Quinolinol showed a significant inhibitory effect against Clostridium difficile, C. perfringens, and Escherichia coli, at 5, 2, 1, and 0.5 mg/disk, and also exhibited a very strong inhibitory effect at 0.25 mg/disk. At low concentrations, 8-quinolinol had strong inhibitory effects against C. perfringens at 0.1 and 0.05 mg/disk; 8-quinolinol also manifested a moderate inhibitory effect against C. perfringens at 0.025 mg/disk. Furthermore, 8-quinolinol revealed moderate and weak growth inhibition against C. difficile and E. coli at concentrations of 0.1 and 0.05 mg/disk, respectively, but 2-quinolinol, 4-quinolinol, and 6-quinolinol evidenced no growth inhibition against B. bifidum, B. longum, C. difficile, C. perfringens, E. coli, or L. casei. The inhibitory effects of 8-quinolinol against C. difficile, C. perfringens, and E. coli lead to its consideration as a possible therapeutic modality for the treatment of diseases associated with harmful intestinal bacteria.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.5
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• pp.1490-1493
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• 2004

We investigated antifungal and antioxidant activity of Equsetum arvense L. The sterile stems of Equsetum arvense L. were extracted with methanol and then fractionated with n-hexane, ethyl acetate, butanol, and water. And their antifungal activities were determined by using paper disk diffusion method and (1. 3)β-glucan synthase inhibitory activity assay, and antioxidant activities were determined by using DPPH method. The ethyl acetate fraction showed antifungal activity on Candidas albacans in both disk diffusion and enzyme assays. This also showed antioxidant activity in DPPH assay. Further fractionation with ethyl acetate fraction was performed to obtain effective fractions. 4, 5, 6 and 7 fractions showed the significant antifungal antivities, and, 4 and 5 fractions showed the strongest antioxidative activity.

• Journal of the Korean Wood Science and Technology
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• v.22 no.2
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• pp.61-70
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• 1994

This study was executed to find the applicability of press drying of tree disk by investigating the shrinkage and drying defect and to form appropriate model by comparing the actual moisture content(MC) and internal temperature in respect of drying time with calculated values based computer simulation to which was applied finite difference method. In press drying disk, heating period, constant drying rate period maintained plateau temperature at 100$^{\circ}C$ and falling drying rate period were significantly distinguished. Actual MC and internal temperature were analogous to those calculated at comparing points. Heat transfer model formed by Fourier's law using specific heat of moist wood and conduction coefficient considering fractional volume of each element of wood cell wall, bound water, free water and air showed applicability as basic data to developing heat expansion, shrinkage and drying stress during press drying. Also mass transfer model formed by Fick's diffusion law using water vapor diffusion coefficient showed applicability. Longitudinal shrinkage was developed by pressure of hot press and tangential shrinkage was restrained by hygrothermal recovery. The heart check, surface check and ring failure were occurred differently in species, but V-shaped crack didn't develop.

• YAKHAK HOEJI
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• v.34 no.3
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• pp.161-165
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• 1990

An automated, simple, and reliable method was developed for determining in vitro drug release rate from transdermal delivery dosage forms. The patch is held in position in the heating block by sandwiching it between the middle plate and the bottom plate of diffusion cell. The dissolution profile of the commercially available transdermal scopolamine patch was determined over a 72-h period, and the results were compared with those obtained with other methods; paddle-over-disk method, reciprocating method, and diffusion cell method. It was demonstrated that the flow-through method is equivalent in terms of release rate profile and accumulated released drug amount over the lifetime of the dosage form tested. Also this method is simple, reliable and reproducible. Therefore, this technique can be used in a quality control for assuring product uniformity.

• Journal of dental hygiene science
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• v.18 no.3
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• pp.147-154
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• 2018

This study aimed to evaluate the antimicrobial effects of Acanthopanax sessiliflorum fruit (ASF; Ogaza) extracts on Streptococcus mutans and Streptococcus sobrinus, which are agents that cause dental caries, and on Streptococcus mitis and Streptococcus salivarius, the microbial flora of the oral cavity. The ASF extracts obtained using 70% ethanol were fractionated in the order of ethyl acetate and n-Butanol, concentrated under reduced pressure, and lyophilized to give powdery solvent extracts. The antimicrobial activity of ASF extracts from each solvent was examined using the disk diffusion method. As a result, only those extracts obtained using an ethyl acetate solvent showed antimicrobial activity. These extracts were selected, and the minimum inhibitory concentration was measured by disk diffusion method at various extract concentrations. Results showed a minimum inhibitory concentration of 32 mg/ml. The viable cell count was measured to confirm the minimum bactericidal concentration. Results showed a minimum bactericidal concentration of 64 mg/ml. In the cytotoxicity test using normal human dermal fibroblast cells, the absorbance value of the test group was similar to that of the control group at 0.64, 1.28, and 6.4 mg/ml. The bacteria and their colonies were examined using a scanning electron microscope. Boundaries between the antimicrobial activity region and non-antimicrobial activity region were observed around the paper disk, which was immersed in the extract with 32 mg/ml concentration. Bacterial colonization was not observed in the area with antimicrobial activity. This finding suggests that ASF extracts can inhibit the growth of some microorganisms in the oral cavity, in addition to the effects of these extracts known to date. In particular, ASF extracts may be used as a preparation for preventing dental caries by adding the extract to the toothpaste or oral mouthwash.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.32 no.3 s.58
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• pp.201-208
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• 2006

Propionibacterium acnes have been recognized as pus-forming bacteria triggering an inflammation in acne. The present study was conducted to evaluate antimicrobial activities of Dryopteris crassirhizoma Nakai against these etiologic agents of acne vulgaris and application possibility as a cosmetic resource. D. crassirhizoma crude extract and hexane fraction was prepared and its anti-acne effect against Propionibacterium acnes was investigated with minimum inhibitory concentration (MIC) and paper disk diffusion method. The MIC of D. crassirhizoma crude extract and hexane fraction was 0.008 mg/mL and 0.001 mg/mL, respectively. This implies that D. crassirhizoma extract may be an efficient anti-acne ingredient for cosmetics, as a crude extract. The paper disk diffusion assay showed that its anti-acne effect was similar to that of triclosan. The cytotoxic effect of D. crassirhizoma extract was determined by a colorimetric MTT assay using HaCaT cell line and D. crassirhizoma extract exhibited lower cytotoxic effects. Finally, we examine the stability of D. crassirhizoma extract to temperature and pH. The D. crassirhizoma extract was very stable to high temperatures ($25{\sim}121^{\circ}C$) and to wide pH range ($pH\; 2{\sim}11$), suggesting its utilization for cosmetics.