• Food Science and Preservation
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• v.12 no.4
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• pp.323-328
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• 2005

This study were investigated to analyzed an optimum preparation condition of coating film and its antimicrobial activity on pathogenic and deteriorative bacteria to obtain fundamental data for development of active packaging film using antimicrobial peptide, polysine. In the preparation conditions of coating film, antimicrobial activity was depending on the concentration of polylysine and polyamide respectively, and relatively high activity was obtained in the film prepared with more than $1.0\%$ (w/v) of polylysine, $40\%$ (w/v) polyamide, and more than $50\;{\mu}m$ of film thickness. Concentration of polylysine migrated from coated film to distilled water was reached at the maximum concentration, about 20 ppm after 3 days and in equilibrium after 7 days of soaking in sterilized water. An antimicrobial activity of coated film showed bactericidal effect of about $10^5\;CFU/mL$ comparing with the control against Bacillus cereus having $4.8{\times}10^5\;CFU/mL$ of initial viable cell numbers, and of about $10^2\;CFU/mL$ comparing with the control against Klebsiella pneumoniae having $6.8{\times}10^5\;CFU/mL$ of initial viable cell numbers. Consequently, it was revealed that polylysine coating film has a potential of applicable possibility as antimicrobial packaging film.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.261-264
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• 2001

Cytotoxicity and antibacterial activity of preservatives were examined. Fibroblast cell L929 was used for cytotoxicity experiment and Pseudomonas aeruginosa A TCC27853, Staphylococcus aureus ATCC25923. Trichoderma reesei ATCC6967 were used for antibacteria and antifungi. Benzalkoniumchloride(BAK) as synthetic preservative and chitosan as natural preservative were used. Minimum inhibitary concentration (MIC) of BAK was 0.1 % for P. aeruginsa and 0.001% for S. aureus and 0.1 % for T reesei MIC of chitosan was 2% for P. aeruginosa and 1 % for S. aureus.

• Journal of Life Science
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• v.14 no.3
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• pp.411-416
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• 2004

In this study, we investigated the biological activity of antioxidant and antimicrobiological effect of Chondria crassicaulis (CC), which, using methanol, dichlolometane and ethanol, were extracted and fractionated into four different types: hexane(CCMH), methanol (CCMM), butanol (CCMB), and aqueous (CCMA) partition layers. The reducing activity on the 1,I-diphenyl-2-picrylhydrazyl (DPPH) radical and $O^{2-}$ and $O_{2}$$O_{2}$radical scavenging potential, in search for antioxidation effects of CC partition layer, were sequentially screened. Among the four fractions, CCMM had the highest antioxidative activity. The antimicrobial activity was increased in proportion to its concentration by the paper disc method. Among the various solvent layers, the CCMB, CCMH and CCMM showed relatively strong antimicrobial activities in the order.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.928-935
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• 2000

This study was carried out to examine the antioxidative, antimicrobial and nitrite scavenging effects of various solvent extracts and different solvent fractions from Schizandra chinensis RUPRECHT(Omija) seed. The results were as follows; The antioxidative activities using lard, soybean oil and linoleic acid were the highest in methanol, ethanol and methanol extract from omija seed, respectively. The free radical scavenging activity using DPPH method was the strongest in acetate fraction of methanol extract from seed. The methanol extract from omija seed had the strongest antimicrobial activities to L. plantarum, B. subtilis, E. coli and P. citrinum, while ethyl acetate extract had the strongest against S. aureus and S. typhimurium. The buthanol fraction from methanol extract had the highest antimicrobial activities, followed by B. subtilis, L. plantarum, E. coli, S. aureus and S. typhimurium. The nitrite scavenging ability was pH dependent, highest at pH 1.2 and lowest at pH 6.0. The buthanol fraction of methanol extract from omija seed had more effective nitrite scavenging ability than other fractions of extracts.

• Applied Biological Chemistry
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• v.35 no.1
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• pp.14-22
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• 1992

A series of new N-[1-(benzotriazol-1-yl)aryl]arylamine derivatives were synthesized and their antifungal activities $(pI_{50})$ in vitro against Pyricularia oryzae, Fusarium oxysporum f. sp. sesami, Valsa ceratosperma and Botrytis cinerea were dertermined by the agar medium dilution method. From the results of the quantitative structure-activity relationships $(QSAR_S)$ analysis, $hydrophobicity({\pi})$, $electronic({\Sigma\sigma})$ and molar $refractivity({\Sigma}M_R)$ parameter of X & Y-substituents on the phenyl group were also shown to be important factor in determining the variation in the antifungal activity. 4-Bromo group substituents (1d & 2b) were the most effective compounds and the $half-life(T_{1/2})$ on the hydrolysis of X(1) at netural pH was about 1.5 day. Molecular orbital(MO) functions of substrate compound, linear free energy relationships$(LFER_S)$ on the antifungal reactivity arid the results of molecular design were also discussed.

• Korean Journal Plant Pathology
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• v.11 no.2
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• pp.165-172
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• 1995

벼 잎집무늬마름병균(Rhizoctonia solani)의 균핵에서 분리한 길항세균 SJ-2를 대치 배양 방법에 의해 벼도열병균(Pyricularia oryzae)외 6종의 식물 병원균에 대한 억제 효과를 조사하였다. 형태 및 생리적 특성을 조사한 결과, 이 균은 Bacillus subtilis로 동정되었다. 이 균은 AM 1(antibiotic medium 1)액체 배지에서 항균 물질을 분비하였으며, 배양 2일째 가장 항균 활성이 높았다. Butyl alcohol로 배양액에서 항균 물질을 조추출하여 100$\mu\textrm{g}$/ml의 농도로 조제한 감자 한천 배지에서 P. oryzae의 15개균에 대한 생육을 조사한 결과 P. oryzae, R. solani, Cochliobolus sativus에 대해서는 100% 생장을 억제하였으며, C. miyabeanus, Alternaria alternata, Botrytis cinerea, Cladosporium fulvum, Colletotrichum gloeosporioides, Fusarium moniliforme, F. oxysporum에는 80% 이상의 억제 효과를 보인 반면 난균강에 속하는 병원균에 대한 효과는 낮게 나타났다. 활성물질을 분리 정제하여 동정한 결과 B. subtilis가 분비하는 항균 물질로 알려진 polypeptides계의 iturins로 밝혀졌다. 이러한 항균 물질은 벼 도열병균(P. oryzae)의 포자 발아 및 발아관의 팽대(swelling)를 야기했으며, 벼 잎집무늬마름병균(R. solani)에는 균사의 용균(lysis)현상을 일으켰다.

• Journal of the Korean Chemical Society
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• v.44 no.1
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• pp.37-44
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• 2000

In order to develope bioactive substances, dried fmit body of Daedalea dickinsii collected from Taeback mountain was extracted with ethanol, The compounds 1 and 2 were purified by solvent extraction, silica gel column chromatography and recrystallization from the ethanol extracts. Melting point, molecular weight and molar extinction coefficient of the compound 1 were estimated to be $167{\sim}168^{\circ}C$, 572 and 5,040 at 208 nm. The structure of this compound 1 has been elucidated to be 24S, 25S, $3{\alpha}-carboxyacetylquercinic$ acid using spectroscopic properties. This compound showed antibiotic activities against fungi, yeasts and bacteria and it also showed anticancer activity $IC_{50}=64.5\;{\mu}M$) against Korean stomach cancer cell. Melting point, molecular weight and molar extinction coefficient of the compound 2 were estimated to be $233{\sim}235^<\circ}$, 572 and 5,080 at 208 nm. The structure of this compound was elucidated to be 24S, 25R, $3{\alpha}-carboxyacetylquercinic$ acid. The compound 2 showed different antibiotic activities with the compound 1.

• Journal of fish pathology
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• v.14 no.1
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• pp.3-10
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• 2001

The present study was to obtain a basic research data about medicinal herbs by screening in vitro antimicrobial activity and the production of superoxide anion($O_2^-$) from the head kidney phagocytes of olive flounder, Paralichthys olivaceus. The following fourteen kinds of medicinal herbs extracted by boiling water were used : Gosam, Gwijeonu, Gujeolcho, Bagha, Bangpung, Yeongyo, Yagssug, Jiyu, Sambaegcho, Samjiguyeobcho, Sangbaegpi, Sohwehyang, Pyeonchug, Palgag. Antimicrobial activity against fish pathogenic bacteria, Listonella anguillarum, Vibrio sp., Vibrio alginolyticus, Edwardsiella tarda, Streptococcus sp. and Lactococcus garvieae, and the production of superoxide in kidney macrophage of olive flounder were examined by disk method and nitroblue tetrazolium(NBT) reaction, respectively. Among the tested herbs, Yagssug showed the highest antimicrobial activity against those fish pathogenic bacteria and stimulation of $O_2^-$ production.

• Korean Journal of Organic Agriculture
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• v.25 no.4
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• pp.821-830
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• 2017

In this study, the DPPH free radical scavenging activity, antimicrobial effects, growth inhibition and cytotoxicity of herb extracts were determined to screen alternative antibiotics. Hot water extracts of 10 species herbs (Origanum vulgare, Monarda didyma, Echinacea purpurea, Ocimum basilicum, Mentha piperita, Melissa officinalis, Thymus vulgaris, Stevia rebaudiana, Rosmarinus officinalis, Matricaria recutica) were used. DPPH free radical scavenging activity of all herb extracts was ranged from 31.4-49.9%, and significantly great activties were found at Rosmarinus officinalis, Origanum vulgare and Matricaria recutica (P<0.05). Hot water extracts of monarda didyma, origanum vulgare, thymus vulgaris and rosmarinus officinalis showed greater antimicrobial activities compared to others. Additionally, those four extracts represented relatively low cytotoxicity compared to others. As a result, it was found that Origanum vulgare and Rosmarinus officinalis which possessed great antioxidant and antimicrobial activity with less cytotoxicity. So these two herb extracts can be used as an alternative of antibiotics for organic farming.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.299-305
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• 2010

The purpose of this study was to investigate antimicrobial, antioxidant, DPPH radical scavenging and SOD-like activity effect of Jubak(AFC) extract using hot water and ethanol solvent. All extracts from Jubak(AFC) had antimicrobial activities in the Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. Antioxidant activities of the Jubak(AFC) using soybean oil emulsion was confirmed to be higher in the extract using ethanol and hot water than control and the antioxidant was practically effective when concentration of the Jubak was 200 ppm. Scavenging effect of DPPH radical of Jubak extracts showed inhibition effect was above 80%. SOD-like activity were higher in hot water extracts than in ethanol extracts. If keeping up Jubak's study, it could have potential as a cosmetic raw material. Additionally, Jubak could be expected as functional material in food by different extract method.