• Natural Product Sciences
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• 제23권1호
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• pp.5-8
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• 2017

An antimicrobial compound has been isolated from the leaves of Glochidion superbum. The compound was determined as methyl 3, 4, 5-trihydroxybenzoate (methyl gallate), based on ultraviolet (UV), infrared (IR), nuclear magnetic resonance (NMR) and mass spectroscopy (MS) analysis. The isolated compound exhibited potent antimicrobial activity against three clinical isolates of methicillin resistant Staphylococcus aureus (MRSA) by qualitative agar disc diffusion method and quantitative broth dilution method. Agar disc diffusion was done in a dose-dependent manner for each bacterial isolate at disc potencies of 25, 50, 100, and $150{\mu}g/disc$. The zones of inhibition were on average equal to 12.27, 14.20, 15.43, and 24.17 mm respectively. The inhibition zones were compared with that of vancomycin disc at $30{\mu}g$ as a reference standard. The MIC and MBC values were $50{\mu}g/ml$ and $100{\mu}g/ml$ respectively. The results of anti MRSA activity were analyzed using one-way ANOVA with Turkey's HSD and Duncan test. In conclusion, methyl gallate which was isolated from G. superbum showed the inhibition activity against methicillin resistant S. aureus.

• 한국수산과학회지
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• 제49권6호
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• pp.838-844
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• 2016

In this study, epidemiological cut-off values were estimated for 44 Photobacterium damselae isolates, since clinical breakpoints have not been established for this pathogenic bacterium. The susceptibility of the isolates to 10 antibiotics was evaluated using internationally standardized disc diffusion protocols. Normalized resistance interpretation was used to generate statistically valid epidemiological cut-off values for the susceptibility data. There were not enough strains exhibiting full sensitivity to ampicillin and amoxicillin to allow analysis of these antibiotics. Because there were only a marginally sufficient number of strains exhibiting full sensitivity to oxytetracycline, the cut-off value generated provided only a provisional estimate. The valid wild-type cut-off values were <13, 13, 9, 22, 25, 27, and 28 mm for gentamicin, cephalexin, erythromycin, oxolinic acid, flumequine, florfenicol, and sulfamethoxazole/trimethoprim, respectively. The application of these cut-off values should greatly facilitate the rational selection of antibiotics for use in commercial fish farms.

• Animal cells and systems
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• 제8권2호
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• pp.111-115
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• 2004

The epidermis of the mudskipper, Periophthalmus modestus, consists of three layers- the outermost layer, middle layer and stratum germinativum. Extensive fine blood capillaries are present near the superficial layer of epidermis and outermost layer in five fins and a sucking disc. The diffusion distance between the vascular capillaries and the surface of epidermis ranged from 3.6 to 10.9${\mu}$m: 3.6 ${\mu}$m in the sucking disc, 10.9 ${\mu}$m in the anal fin and 4.6 to 5.0 ${\mu}$m in the two dorsal fins. Rate of the surface area of respiratory epithelium, the surface area of the fine blood capillaries occupied per surface area of epidermis in 0.1mm, is 3.7 to 4.4% in two dorsal fins and 1.1% in the anal fin. The middle layer is simpler in structure consisting of small or voluminous cells swollen by epidermal cells, and this layer appeared web-like. Well-developed lymphatic spaces containing lymphocytes existed in the stratum germinativum. The five fins and sucking disc had no epidermal glands.

• 한국식품과학회지
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• 제11권2호
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• pp.118-121
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• 1979

Under the experimental conditions of varying the thickness(2L cm) of ginseng disc and the bulk, concentration $(C_b.{\;}%)$, the experimental results were well coincided with those of the model which was set up by using the inter disc diffusion with constant diffusivity. It was therefore convinced that the extraction rate is controlled by the diffusion rate of ginseng components through the disc. The relationship between the diffusivity$(D{\;}cm^2/min)$ and the mean concentration (C %) of soluble ginseng components in the disc is as follows, $ln{\frac{C-C_{b0}}{C_i-C_{b0}}}=ln{\frac{8}{{\pi}^2}-{\frac{{\pi}^2D}{4L^2}{\theta}$ where $C_i(%)$ is the initial concentration of soluble ginseng components and $\theta$ (min.) is the extraction time.

• 한국치위생학회지
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• 제18권1호
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• pp.9-18
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• 2018

Objectives: Pleurotus eryngii is used both for edible and medicinal purposes, and has a physiological activity. The purpose of this study is to investigate the antibacterial effect of Pleurotus eryngii against six oral pathogens (Staphylococcus aureus, Streptococcus criceti, Streptococcus mutans, Streptococcus ratti, Streptococcus sobrinus, and Actinomyces viscosus). Methods: The antibacterial activities of various extracts of Pleurotus eryngii were examined by disc diffusion assay and minimum inhibitory concentration (MIC). The disc diffusion assay was performed by putting a paper disc soaked in extracts on plates inoculated bacterial cultures. The MIC of these extracts was determined by using a broth microdilution assay at a concentration ranging between 0.03 mg/ml to 15.00 mg/ml. The growth inhibition effect of extracts was measured at 600 nm for 24 hrs. Results: The antibacterial activity was confirmed against all six tested bacteria at Pleurotus eryngii ethyl acetate extract by the disc diffusion method. Acetone extract showed the antibacterial activity only against 4 strains containing Streptococcus criceti, Streptococcus mutans, Streptococcus ratti, and Actinomyces viscosus. In ethanol extract, no activity was observed against other strains except Staphylococcus aureus. MIC values of ethyl acetate extract were the same, 7.50 mg/ml in all tested bacteria. Conclusions: Pleurotus eryngii exhibited the antibacterial activity against oral pathogens (Staphylococcus aureus, Streptococcus criceti, Streptococcus mutans, Streptococcus ratti, Streptococcus sobrinus, and Actinomyces viscosus). Thus, Pleurotus eryngii may be considered as a natural antibacterial agent for treatment of dental diseases.

• 한국광학회:학술대회논문집
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• 한국광학회 2001년도 하계학술발표회
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• pp.72-73
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• 2001

• 한국식품조리과학회지
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• 제27권4호
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• pp.17-26
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• 2011

본 연구는 지유 에탄올 추출물의 항균 및 항돌연변이 활성을 측정하여 새로운 기능성 소재로서의 기초자료를 얻고자 실시하였다. E. coli, E. coli O157:H7, P. aeruginosa, S. Typhimurium, L. monocytogenes, B. cereus, S. aureus의 7가지 주요 식품위해성 세균에 대한 항균활성을 검증하기 위해 paper disc diffusion assay 및 최소저해농도를 측정하였으며 24시간 동안 균의 생육억제도를 측정하였다. Paper disc assay 결과 E. coli와 E. coli O157:H7을 제외한 5가지 균에 대한 지유 에탄올 추출물의 뚜렷한 clear zone이 확인되었다. Micro-well dilution법으로 확인한 최소저해농도의 범위는 E. coli와 E. coli O157:H7을 제외한 5가지 균에 대해서 0.625~2.5 mg/mL로 나타났으며 생육억제도 실험결과도 최소 저해농도 결과와 일치하였다. Salmonella Typhimurium TA100을 이용한 Ames test 결과, 5 mg/plate의 농도에서 직접 돌연변이원인 sodium azide와 4-NQO에 대한 지유 에탄올 추출물의 항돌연변이 활성이 각각 72.42와 89.85%로 나타나 지유 에탄올 추출물의 우수한 항돌연변이 활성을 확인하였다. 본 연구를 통해 지유 에탄올 추출물이 주요 식품위해성 세균들에 대한 우수한 항균성과 직접돌연변이원에 대한 높은 항돌연변이 활성을 나타내어 천연물 유래 생리활성 소재로 이용될 수 있는 가능성을 보여주었다.

• Advances in Traditional Medicine
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• 제8권1호
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• pp.53-58
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• 2008

The plant Quisqualis indica (Compositae) has ehnopharmcological reputation of being used as a healing agent in Bangladesh. In this study, preliminary screenings were conducted to look at the antimicrobial susceptibility and cytotoxicity of the plant extract. The extractives of the plant were subjected to screening for inhibition of microbial growth by the disc diffusion method. The zones of inhibition demonstrated by the n-hexane, carbon tetrachloride, chloroform and aqueous soluble partitionates of the methanolic extract ranged from 8 - 15 mm, 8 - 18 mm, 12 - 20 mm and 10 - 16 mm, respectively at a concentration of 400 ${\mu}g$/disc. All the extractives were also subjected to brine shrimp lethality bioassay for primary cytotoxicity evaluation. Here, the carbon tetrachloride soluble materials demonstrated the highest cytotoxicity with $LC_{50}$ of 0.826 ${\mu}g$/ml, while n-hexane, chloroform and aqueous soluble partitionates of the methanolic extract revealed the $LC_{50}$ of 1.254, 3.866 and 5.366 ${\mu}g$/ml, respectively. This is the first report of the antimicrobial activity and cytotoxicity Q. indica.

• Korean Journal of Radiology
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• 제23권2호
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• pp.218-225
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• 2022

Objective: This study aimed to explore the feasibility of functional evaluation of the lateral pterygoid muscle (LPM) using diffusion tensor imaging (DTI) in patients with temporomandibular joint disorders (TMDs). Materials and Methods: A total of 119 patients with TMD (23 male and 96 female; mean age ± standard deviation, 41 ± 15 years; 58 bilateral and 61 unilateral involvements for a total of 177 joints) and 20 healthy volunteers (9 male and 11 female; 40 ± 13 years; 40 joints) were included in this prospective study. Based on DTI of the jaw in the resting state, the diffusion parameters, apparent diffusion coefficient (ADC), fractional anisotropy (FA), λ1, λ2, and λ3 of the superior and inferior heads of the LPM (SHLPM and IHLPM) were measured. Patients with TMD with normal disc position (ND), anterior disc displacement with reduction (ADWR), and anterior disc displacement without reduction (ADWOR) were compared. Results: Patients with TMD overall, and ADWR and ADWOR subgroups had significantly higher ADC, λ1, λ2, and λ3 in both the SHLPM and IHLPM than those in volunteers (p < 0.05 for all), whereas the ND subgroup only had significantly higher ADC and λ1 (p < 0.001). Meanwhile, significant differences in FA in the SHLPM and IHLPM were found between volunteers and ADWOR (p = 0.014 and p = 0.037, respectively). Among the three TMD subgroups, except for λ3 and FA in the ADWR subgroup, ADWR and ADWOR subgroups had significantly higher ADC, λ1, λ2, and λ3 and lower FA than those in the ND group (p < 0.050). There was no significant difference in diffusion variables between ADWR and ADWOR. In ADWOR, the osteoarthritis group had significantly higher λ3 and lower FA values in the IHLPM than those in the non-osteoarthritis group. Conclusion: DTI successfully detected functional changes in the LPM in patients with TMD. The unsynchronized diffusivity changes in the LPM in different subgroups of TMD signified the possibility of using diffusion parameters as indicators to identify the severity of LPM hyperfunction at various stages of TMD.

• Advances in Traditional Medicine
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• 제8권3호
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• pp.316-321
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• 2008

A total of 33 extracts representing 26 plant species belonging to 24 families were collected from different regions of Bangladesh, and screened for their in vitro antibacterial activity against several pathogenic Gram-positive and Gram-negative bacterial strains using the conventional disc diffusion method. The most potent activity was exhibited by the extracts of Aegiceras corniculatum, Alocasia fornicata, Ceriops decandra, Cuscuta reflexa, Lasia spinosa, Lantana camara, Pandanus foetidus and Xylocarpus granatum. The extracts of Abtilon indicum, Derris trifoliata, Dendrophthoe falcat, Ruellia tuberosa and X. moluccensis did not show any antibacterial properties at test concentrations.