• The Plant Pathology Journal
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• v.15 no.1
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• pp.14-20
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• 1999

Twenty isolates of Helminthosporium species were obtained from various grass plants and tested for controlling efficacy on the development of plant diseases. An isolate of Helminthosporium sp. TP-4 was chosen and six antibiotic substances were purified from cultures of the fungus by repeated silica gel column chromatography and preparative thin-layer chromatography. They were identified as ophiobolin a, 6-epiophiobolin A, 3-anhydroophiobolin A, 3-anhydro-6-epiophiobolin A, iphiobolin B, and iphiobolin I mainly by mass spectrometry and nuclear magnetic resonance spectrometry. Ophiobolins inhibited the growth of a grampositive bacterium Streptomyces griseus, but were not active against gram-negative bacteria. They also showed an antifungal activity. In in vivo tests, iphiobolin B exhibited potent controlling activities against rice blast, tomato late blight, and wheat leaf rust with control values more than 90% and 70% at concentration of $500\mu\textrm{m}$/ml and 100 ${\mu}{\textrm}{m}$/ml. Ophiobolin A and 6-epiophiobolin A controlled the development of wheat leaf rust more than 80% at concentrations of 100 /ml and $500\mu\textrm{m}$/ml respectively. 3-Anhydro-6-epiophiobolin A was not active against any plant disease. On the other hand, the A-series ophiobolins other than 3-anhydroophiobolin A showed stronger phytotoxic activity in a leaf-wounding assay using 8 plant species than those of 3-anhydroophiobolin A, ophiobolin B, and ophiobolin I. The results indicate that there is little correlation between antifungal activity and phytotoxicity of ophiobolins.

• YAKHAK HOEJI
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• v.30 no.5
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• pp.232-237
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• 1986

A series of modified poly(acrylic acid)'s containing different levels of 6-aminopenicillanic acid (6-APA), 7-aminocephalosporanic acid (7-ACA) and 6-[D-(-)-$\alpha$-aminophenyl acetamido] penicillanic acid (ampicillin) as pendant groups were prepared. Antibiotic activities of the newly prepared drugs were examined against the various gram-positive and gram-negative bacteria. It was found that ampicillin modified composition posses antibiotic activities against the gram-negative as well as the gram-positive bacteria.

• 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.

• YAKHAK HOEJI
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• v.56 no.5
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• pp.320-325
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• 2012

To develop a new effective and safe natural antibiotics and antioxidant the essential oil was extracted from the roots of Anthriscus sylvestris by steam distillation. Its composition was analyzed by GC-MS. The activities of the essential oil fraction and its main components were evaluated against antibiotic-susceptible and -resistant strains of some food-born bacteria. In addition the synergism was examined with this oil combined with antibiotic by checkerboard titer test. The antioxidant activities were determined by in 1,1-diphenyl-2-picryl-hydrazil (DPPH) free radical scavenging activity test and reducing power assay. The essential oil fraction of A. sylvestris revealed significant inhibiting activities against antibiotic-susceptible and -resistant species of Vibrio and Shigella with MICs ranged from 1.00~4.00 mg/ml. It showed synergistic or additive effects when it was combined with amphicillin or trimethoprim/sulfamethoxazole (1 : 9). Additionally, the essential oil fraction of A. sylvestris exhibited significant DPPH free radical scavenging activity and the reducing power.

• YAKHAK HOEJI
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• v.49 no.4
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• pp.312-316
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• 2005

To develop a new natural antibiotics from Koran plant resources for dealing with the current situation regarding the rapid increase in antibiotic-resistant pathogen, the in vitro inhibitory activities of essential oils from the young leaves of Glehnia littoralis (Umbelliferae) as well as its main constituents were evaluated against susceptible and resistant species of Streptococcus pneumoniae. The essential oil fraction of G. littoralis and its main components, $\alpha-and\;\beta-pinene$, exhibited significant inhibitory activities against the antibiotic-susceptible and resistant strains of S. pneumoniae, with MICs (minimum inhibiting concentrations) ranging from 4.0mg/ml to 16mg/ml. No remarkable differences were shown between the susceptible and resistant strains. Moreover, the disk diffusion test disclosed that these inhibitory activities were dose­dependent. Furthermore, data from the checkerboard titer test with FICIs (fractional inhibiting concentration indices) from 0.15 to 0.28 indicated synergisms between norfloxacin and $\alpha-or\;{\beta}-pinene$ in activity against S. pneumoniae KCCM49629 and S. pneumoniae CCARM4059.

• The Korean Journal of Mycology
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• v.23 no.1 s.72
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• pp.37-45
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• 1995

In order to study antibiotic activities of basidomycetes (mushroom), 68 species of mushroom were extracted with petroleum ether, 80% ethanol, and distilled water in that order. A total of 204 extracts were obtained. Antibiotic activities against Microsporum gypseum were observed from the petroleum ether extracts of Abortiporus DGU-L6 mushroom, and the water extracts of Clitogbe DGU-7 mushroom. Antibiotic activity against Aspergillus niger were observed from the 80% ethanol extracts of Cortinarius DGU-51 and Marasmminus DGU-L67 mushroom. The petroleum ether extracts of Hetero DGU-L25 mushroom showed various antibiotic activities, particularly strong activities against M. canis. and the minimum inhibitory concentration (MIC) was $40\;{\mu}g/ml$. The extracts also showed antibiotic activities against A. niger (KCTC 2025), A. niger (KCTC 2118), A. versicolor (KCTC 2120), A. flavus (KCTC 2117), M. gypsem, Pyricularia oryzae, and Trichopyto mentagrophytes, and MIC for each fungus was $600\;{\mu}g/ml,\;500\;{\mu}g/ml,\;800\;{\mu}g/ml,\;100\;{\mu}g/ml,\;600\;{\mu}g/ml,\;200\;{\mu}g/ml,\;and\;600\;{\mu}g/ml$, respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.541-544
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• 2004

The purpose of this study is to examine the antibiotic and physical properties of antibiotic concrete added inorganic liquor-type antibiotic agent(as named for Antibio-C) as the basic data for the development of antibiotic concrete. The main experimental variables were the types of antibiotic agents and it is tested for the properties of antibiotic, flow, compressive strength, crack-resistance and durability of concrete. As results, concrete containing antibiotic agent presented the strong antibiotic activities compared with non-added concrete. Also antibiotic concrete showed the higher or equality properties than non-added concrete with respect to compressive strength, crack resistance and durability such as neutralization depth.

• Natural Product Sciences
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• v.17 no.4
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• pp.296-302
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• 2011

We determined the inhibitory activity of the essential oil fraction obtained by steam distillation from the fresh and dried leaves of Perilla frutescens var. acuta against some pathogenic Salmonella and Vibrio spp. The activities of compounds isolated from the essential oils, apiol and myristicin, were also tested and the results were compared with those of the essential oil fraction. The Perilla essential oil fraction and its main components showed significant inhibition against antibiotic-susceptive and antibiotic-resistant strains of the tested Salmonella and Vibrio strains. Synergistic or additive effects were identified by combing the oils with ampicillin by checkerboard-titer tests. We conclude that essential oils from P. frutescens can be useful in the treatment of Salmonella and Vibrio infections and as safe additives to food materials for the prevention of contamination of food by these bacteria. This is especially important because of the rapid increase in antibiotic-resistant strains, which could cause severe symptoms in humans.

• Korean Journal of Pharmacognosy
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• v.22 no.1
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• pp.45-50
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• 1991

The combined effect of berberine isolated from the bark of Phellodendron amurense and some antibiotics was evaluated in order to measure the antibiotic activities. In this study, in the presence of streptomycin, tetracycline, cephradine as antibiotics, Staphylococcus aureus, Escherichia coli, Shigella sonnei as microorganisms were grown in an Automated Microbiology System. In case of Staphylococus aureus, combination with berberine and cephardine resulted in the strongest synergistic activity and in case of Escherichia coli and Shigella sonnei, combination with berberine and streptomycin resulted in the strongest synergistic activity. The combination with berberine and antibiotics increased the antibiotic activities, thereby showing a synergistic action.

• Korean Journal of Microbiology
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• v.15 no.4
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• pp.154-158
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• 1977

Fifteen kinds of antibiotics both in liquid or dry stantes wre investigated for the purpose of radiation effect on the antibiotic activities after irradiation. In liquid states, the antibiotics such as amoxyllin, ampicillin, capharolidin and hetacillin were inctivated 90% of their antibiotic activities at radiation doses of 50Krad, and penicillin, dicloxacillin, caphalothin, cloxacillin, erythromycin and caphalexin and kanamycin were decomposed at radiation doses of 1.5Mrad, respectively. In dry states, all antibiotics were stable at radiation doses of 5Mrad. On the other hand, the neomycin in liquid state was rather increased the antiboctic activity about 1.2 and 8 times when the E. coli ATCC 113-3 and B. subtitilis ATCC 6633 were used aas a standard microorganisms, whereas, the decrensed antibiotic activities were observed in S. typhi Ty-2(36.2%), St.faecium(10.79%), B.sphaericus CIA(9.066%) and St.aureus ATCC 6538p(70%).