• Natural Product Sciences
• /
• v.11 no.2
• /
• pp.92-96
• /
• 2005

The antifungal activities of essential oils from the leaves of Glehnia littoralis, which is cultivated in Korea, were evaluated against pathogenic Trichophyton species by the broth dilution method and the disk diffusion test. Additionally, the effects of the oils together with ketoconazole were tested by the checkerboard titer test. The essential oil fraction and its main components showed significant inhibition of the tested Trichophyton fungi, with minimal inhibitor concentrations (MICs) in the range of 16-32 mg/ml. The results suggest that activities of this oil are based mainly on the contents of ${\alpha}-pinene$ (22.17%), the next prominent component of the oil fraction, while the first main components ${\beta}-pinene$ (57.83%) have relatively mild activity. The MICs of ${\alpha}-pinene$ and ${\beta}-pinene$ were 1-4 mg/ml and 4-32 mg/ml, respectively. Additionally the Glehnia oil fraction and its main components as well, exhibited significant synergism with ketoconazole against Trichophyton rubrum.

• Natural Product Sciences
• /
• v.16 no.3
• /
• pp.175-179
• /
• 2010

The present study aimed to assess the antifungal properties of the essential oil fraction from Ligusticum chuanxiong (Umbelliferae) and its components against five clinically important Aspergillus species. The essential oil fraction was extracted from the underground parts of the plant by steam distillation, and its main components, namely, Z-ligustilide, butylidene phthalide, and p-cresol were isolated by column chromatography. The antifungal activities of the essential oils were evaluated by the broth dilution method. Both the total essential oil fraction of L. chuanxiong and its components showed significant anti-Aspergillus activity against all five tested strains with MICs between 62.5 and 250 ${\mu}g$/ml, respectively. In a checkerboard microtiter assay, the combination of antibiotics, itraconazole with the essential oil fraction of L. chuanxiong or its main components exhibited synergistic or additive, and in some cases indifferent, effects against the tested Aspergillus species, resulting in FICIs (fractional inhibiting concentration indices) ranging from 0.12 to 2, while the combination of antibiotics, amphothericin B with L. chuanxiong essential oils mostly showed antagonistic effects.

• YAKHAK HOEJI
• /
• v.46 no.3
• /
• pp.203-207
• /
• 2002

The antifungal activities of the essential oils from Anthemis nobilis, Ciderus atlantica, Juniperus communis, Lavandula angustifolia, Pelargonium graveolens, Pogestemon patchouli, Rosmarinus officinalis, and Styrax tonkinensis which are recommended for the treatment of microbial infections in aromatherapy and complementary medicines were tested against Candida spp. The activities were measured by broth dilution method and disk diffusion assay. Most of the test oils inhibited growth of Candida albicans, C. utilis and C. tropicalis. Especially, the essential oil from Pelargonium graveolens and its main component, citronellol showed the strongest activity among the herbs except benzoic acid from Styrax tonkinensis which is well-known antimicrobial compound. As a result of checkerboard microtiter test. synergistic effect of citronellol, was shown when the component was combinated with ketoconazole, displaying a fractional inhibiting concentration (FIC) index of 0.37 against C. albicans.

• Archives of Pharmacal Research
• /
• v.17 no.6
• /
• pp.438-442
• /
• 1994

Antimicrobial activity of GL (the aqueous extract from the carpophores of Ganoderma lucidum ($F_RK_{KARST}$) was tested in vitro aginst Gram positive and Gram negative bacteria by serial broth dilution method, and the antimicrobial activity was expressed by minimal inhibitory concentration (MIC). Among fifteeen species of bacteria tested, the natimicrobial activity of GL was of antimicrobial combinations of GL with four kinds of antibiotics (ampicilin, cefazolin, oxytet-racycline and chloramphenicol), the fractional inhibitory concentraction index (FICI) was determined by checkerboard assy for each stain. The antimicrobial combinations of GL with four antibiotics resulted in additive effect in most instances, synergism in two instances, and antagonism in two instances. Synergism was obversed when GL was combined with cefazolin against Bacillus subtilis and Klebsiella oxytoca.

• Archives of Pharmacal Research
• /
• v.26 no.5
• /
• pp.389-393
• /
• 2003

The essential oils from Cedrus atlantica, Styrax tonkinensis, Juniperus communis, Lavandula angustifolia, Melaleuca alternifolia, Pelargonium graveolens, Pogestemon patchouli and Rosmarinus officinalis were analyzed by GC-MS. Antifungal activities of the oils were investigated by disk diffusion assay and the broth dilution method against Aspergillus niger and A. flavus. The effects of geraniol and the essential oil fraction from P. graveolens on the antifungal activity of amphotericin Band ketoconazole were examined using a checkerboard microtiter assay against both Aspergillus fungi. Most of the tested essential oils, with the exception of C. atlantica, J. communis, and P. patchouli, significantly inhibited growth of A. niger and to a lesser extent that of A. fIavus, with MICs (minimal inhibitory concentrations) in the range 0.78-12.5 mg/mL. The essential oil fraction of P. graveolens and its main components, geraniol and citronellol, exhibited additive effects with amphotericin B and with ketoconazole against both Aspergillus species, resulting in fractional inhibitory concentration (FIC) indices ranging from 0.52 to 1.00.

• Korean Journal of Pharmacognosy
• /
• v.31 no.4
• /
• pp.407-411
• /
• 2000

Antibacterial activities of magnolol (MGL) and honokiol (HKL) in combination with four representative antibiotics-amoxicillin (AMPC), oxytetracyclin (OTC), gentamicin (GM) and chloramphenicol (CAP)-were evaluated against four bacterial strains. When tested by disk-plate method, five out of eight combinations such as HKL-AMPC, HKL-CAP, MGL- AMPC, MGL-OTC, and MGL-CAP showed additive to synergistic interaction against gram- negative bacterium Salmonella typhimureum. Of these, MGL-AMPC combination turned out to be antagonistic against Sarcina lutea and Bacillus thurungiensis. Against these two grain-positive bacteria, only HKL-GM combination showed additivity to synergism. All the other combinations showed no interactions. Despite these results, however, no synergism was observed in checkerboard titration assay.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2019.06a
• /
• pp.236-237
• /
• 2019

본 논문에서는 가상의 체스보드판을 이용한 카메라 캘리브레이션 방법을 제안한다. 제안된 방법에서는 카메라 포즈나 체스보드판의 움직임을 모사하기 위해 가상 카메라로 획득한 여러 포즈의 체스보드 이미지를 디스플레이에 표시하고 디스플레이를 캘리브레이션 대상이 되는 카메라로 촬영한다. 가상 체스보드 격자점좌표와 촬영된 이미지의 체스보드 격자점좌표 사이의 homography 행렬로부터 카메라 파라미터에 대한 제한조건을 추출할 수 있음을 보였고, 렌즈 왜곡을 고려한 전체 카메라 캘리브레이션 방법 또한 제안하였다.

• Korean Journal of Plant Resources
• /
• v.29 no.6
• /
• pp.699-703
• /
• 2016

Methicillin-resistant Staphylococcus aureus (MRSA) is a serious clinical and an urgent problem worldwide. Few new drugs are available against MRSA, because MRSA has the ability to acquire resistance to most antibiotics, which consequently increases the cost of medication. In the present study, the antibacterial activity of Hydnocarpi Semen was investigated. The most effective method is to develop antibiotics from the natural products without having any toxic or side effects. Therefore, there is a need to develop alternative antibacterial drugs for the treatment of infectious diseases. Five Clinical isolates (MRSA) were obtained from five different patients at Wonkwang University Hospital (Iksan, South Korea). The Other 2 strains were ATCC 33591 (Methicillin-resistant strain) and ATCC 25923 (Methicillin-susceptible strain). Antibacterial activity (Minimal Inhibitory Concentrations, MICs) was determined by broth dilution method, disk diffusion method, MTT test, and checkerboard dilution test. Antibacterial activity of n-hexane fraction was remarkable, and had a MICs ranging from $31.25-125{\mu}g/m{\ell}$. FICI values for HFH+AM and HFH+OX were 0.13-0.19 and 0.04-0.29, showing the increase of synergistic effect. When combined together, these antibacterial effects were dramatically increased.

• Structural Engineering and Mechanics
• /
• v.45 no.6
• /
• pp.759-777
• /
• 2013

In this paper, a topology optimization method based on the element independent nodal density (EIND) is developed for continuum solids with multiple load cases and multiple constraints. The optimization problem is formulated ad minimizing the volume subject to displacement constraints. Nodal densities of the finite element mesh are used a the design variable. The nodal densities are interpolated into any point in the design domain by the Shepard interpolation scheme and the Heaviside function. Without using additional constraints (such ad the filtering technique), mesh-independent, checkerboard-free, distinct optimal topology can be obtained. Adopting the rational approximation for material properties (RAMP), the topology optimization procedure is implemented using a solid isotropic material with penalization (SIMP) method and a dual programming optimization algorithm. The computational efficiency is greatly improved by multithread parallel computing with OpenMP to run parallel programs for the shared-memory model of parallel computation. Finally, several examples are presented to demonstrate the effectiveness of the developed techniques.

• The Korea Journal of Herbology
• /
• v.31 no.5
• /
• pp.93-98
• /
• 2016

Objectives : Hwangheuk-san is a complex prescription composed of oriental traditional medicine and has been reported for antioxidant, antimicrobial and anticancer effects in the recent study. Methicillin-resistant Staphylococcus aureus (MRSA) is one of important causes of fatal infectious diseases such as septicemia, endocarditis, toxic shock syndrome, pneumonia, skin and soft tissue infections (SSTIs). S. aureus is reported as being for a variety of human diseases and its epidemiological relevance is mainly due to their ability of becoming highly resistant to common antimicrobials such as tetracycline, penicillin, cphalosporin and aminoglycoside. The objective of this study is to determine the antimicrobial effect of Hwangheuk-san ethanol extracts (HHS) and synergistic effects with antibiotics oxacillin against MRSA.Methods : The antimicrobial activity of HHS was measured by the disc diffusion method, broth microdilution method and the checkerboard dilution test, time-kill curve assay was performed to investigate synergistic effects with antibiotics oxacillin against MRSA.Results : HHS showed antimicrobial activity against MRSA with a MIC value of 125 ㎍/㎖. In the checkerboard test, the interaction of HHS with antibiotics oxacillin produced almost synergy or partial synergy against MRSA. This study showed that HHS reduced the MICs of oxacillin tested, and a remarkable antibacterial effect of HHS, with membrane permeability enhancers.Conclusions : These results suggest that HHS has the antimicrobial effect and synergistic effects with antibiotics oxacillin against MRSA. This study thus can be a valuable source for the development of a new drug with low MRSA resistance.