• Journal of Food Hygiene and Safety
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• v.28 no.3
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• pp.241-246
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• 2013

The objective of this study was to evaluate microbial growth patterns on Korean foods containing collagen. Samgyetang, Ugultang, Odolbyeboguem, Jeonyak, and Jokbal were inoculated with Staphylococcus aureus and Salmonella spp., and incubated at $4^{\circ}C$ (6 days), $10^{\circ}C$ (6 days), $20^{\circ}C$ (3 days), and $30^{\circ}C$ (36 h). Cell counts of S. aureus and Salmonella spp. were enumerated on mannitol salt agar and xylose lysine deoxycholate agar, respectively. Of the 5 foods, S. aureus and Salmonella cell counts decreased (P < 0.05) only in Jeonyak. To understand this reduction in cell growth on Jeonyak, extracts of ingredients such as clove, cinnamon, pepper, ginger, and jujube were examined to determine minimal bactericidal concentrations (MBC; AU/mL). Clove (3.13 AU/mL), cinnamon (50 AU/mL), pepper (25 AU/mL), and ginger (50 AU/mL) extracts displayed antimicrobial activity against S. aureus, and clove and cinnamon extracts displayed antimicrobial activity against Salmonella. The results indicate that Jeonyak has antimicrobial activity against S. aureus and Salmonella, and clove and cinnamon are the primary antimicrobial agents in this food.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.289-292
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• 1995

Fig leaves were extracted with methanol and then fractionated with ethyl acetate and various buffers to get active fractions, and their antimicrobial activities in each fraction were determined. Acidic fraction and phenolic fraction of fig leaves showed strong antimicrobial activities, but the basic fraction and neutral fraction did not show any activities. The degree of antimicrobial activities in phenolic fraction against tested bacteria were higher than those in acidic fraction, but these against yeasts and mold were almost equivalent to those in acidic fraction. Especially, phenolic fraction showed the strongest activities against Staphylococcuns aureus and Pseudomonas aeruginosa. Although there were some differences among microorganisms, minimum inhibition concentrations(MIC) in acidic and phenolic fractions against tested microorganisms were 0.05 to 0.1 g eq./ml and 0.01 to 0.25 g eq./ml, on the basis of fresh sample weight, respectively. Minimum lethal concentrations(MLC) in acidic and phenolic fractions were 0.25 to 2.00 g eq./ml and 0.05 to 1.50 g eq./ml, respectively. These supposed the antimicrobial activities in phenolic fraction were generally higher than those in acidic fraction and also phenolic fraction had lower MIC and MLC values than acidic fraction.

• Korean Journal of Microbiology
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• v.37 no.4
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• pp.305-311
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• 2001

Antifungal bacterium, Bacillus subtilis YS1 was isolated from Yusong hot spring showed broad antifungal spectrum against 12 kinds of plant pathogenic fungi and Candida albicans, animal pathogen. From the gamma($Co^{60}$) radiation sensitivity test, $D_10$ value was 2.08 kGy and it survived above 20 kGy of radiation dose. Several mutants were induced by gamma radiation. Among them, YS1-1009 mutant showed resistance against tebuconazole of herbicide, increased activity against Botryoshaeria dothidea and ligninase activity. YS67 mutant was antifungal deficient auxotrophic mutants(trp-pro-or arg-ura-). From this results, it suggested that gamma irradiation could be useful method for mutant induction.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.345-345
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• 2011

최근 대기압 플라즈마 젯을 이용한 바이오/메디컬의 활발한 응용연구가 진행 중이다. 박테리아 및 세균의 살균은 물론 암세포 세포예정사에 핵심적인 역할을 하는 활성산소종(Reactive Oxygen Species, ROS) 또는 다양한 라디칼들은 대기압 플라즈마의 다양한 변수를 이용하여 조절할 수 있다고 알려져 있다. 수십 kHz의 고전압에서 발생된 마이크로 헬륨 플라즈마 젯에서 질소종의 제어를 통해 같은 부피의 플라즈마 젯에서의 방출광을 살펴보았다. 또한 광섬유센서를 이용하여 플라즈마의 기체온도를 측정하고 Boltzmann plot method를 통해 전자의 여기온도 변화를 관찰하였다. 실험의 결과, 같은 부피의 플라즈마에서 질소종이 증가할 때 기체온도는 큰 변함이 없지만 여기온도가 증가하는 것을 관찰하였다. 시간분해 이미지 촬영으로 질소종의 양에 따른 플라즈마 불릿의 속도 변화를 분석을 하였고, 최종적으로 대기압 플라즈마 젯의 질소종 변화에 따른 대장균의 비활성화 정도를 관찰하였다.

• Journal of the Korean Wood Science and Technology
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• v.28 no.3
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• pp.70-77
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• 2000

Among four compounds such as oxyresveratrol, resveratrol, morin and afzelechin isolated from the heartwood of Morns bombycis, oxyresveratrol and resveratrol which belong to stilbenoid indicated high antioxidative and antimicrobial activity, respectively. Based on this result, this experiment was carried out to elucidate the relationship between biological activities of stilbenoids and their chemical structures using two isolated and six synthesized ones prepared by Wittig reaction. Antimicrobial activity of 3,5-dihydroxystilbene(pinosylvin) devoid of hydroxyl group of B-ring was the best among the tested stilbenoids. Antimicrobial activities of the stilbenoids showed negative dependency on the number of hydroxyl groups of B-ring, that is, the fewer number of hydroxyl groups of B-ring, the higher antimicrobial activity. On the other hand, antioxidative activities of the stilbenoids indicated a positive relationship with the number of hydroxyl groups of B-ring. In tetrahydroxystilbenoids, antioxidative activities of the compounds possessing ortho-diphenol structure, 2',3,3',5- and 3,3',4',5-tetrahydroxystilbene, were superior to the others. As a result, it was concluded that resveratrol and oxyresveratrol isolated from the heartwood of M. bombycis had antimicrobial and high antioxidative activities, and these activities of stilbenoids were also dependent on the number and position of hydroxyl groups of B-ring.

• Korean Journal of Poultry Science
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• v.18 no.3
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• pp.167-181
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• 1991

In order to study the effects of dietary yeast (Saccharomyces cerevisiae) products on the performance of broiler chickens, tow feeding trial using Arbor Acres strain were conducted. In experiment 1, 200 hatched male broiler chickens were divided into groups of 10 birds each and four groups were given each of the five dietary treatments : control, 0.25% yeast culture supplemented (YC-0.25%), 2.5% yeast culture supplemented(YC-2.5%), 0.05% live yeast supplemented(LY-0.05%) and 0.1% live yeast supplemented(LY-0.1%) . In experiment 2, 240 hatched broiler chickens(120 birds in each sex) were assigned to 2$\times$3(sex$\times$feed) factorial design Dietary treatments were control, 0.1% live yeast supplementation in finisher diet(LY-Finisher) , and 0.1% live yeast supplementation in whole period (LY-Whole). Results of experiment 1 showed that weight gain, feed intake and mortality were not significantly different among treatments. However, weight .gain of YC-0.25% and LY-0.1% tended to be greater than other treatments after 3wks of age Feed efficiency of LY-0.05% was poorer than those of control, YC-0.25% and LY-0.1% . Although nutrients availabilities were not significantly different among treatments, availiabilities of Ca and P were greater in yeast products supplemented groups than in control group. The number of Lactobacillus spp., Streptococcus spp . and yeast in small intestine tended to be greater in supplemented groups while that of Coliforms bacteria tended to be greafter in control group. In experiment 2, there were significant effects of factors (feed and sex) and interaction on growth rate. LY-Whole groups showed best weight gain in male while LY-Finisher groups did best in female broiler chickens. Feed intake and mortality were significantly higher in male broiler chickens. Feed$\times$sex interaction had a significant effect on feed efficiency. LY-Whole groups showed best feed efficiency in male while LY-Finisher did best in female broiler chickens. Availabilities of dry matter, Ca and P were higher in male than in female broiler chickens. Availabilities of Ca and P were higher in live yeast supplemented groups than in control groups. Live yeast supplemented groups tended to have greater number of Lactobacillus spp . and yeast in the small intestine and Stre))tococcu spp. in the small intestine and cecum, and lesser number of Coliforms bacteria in the small intestine The pH of small intestinal contents tended to be higher in live yeast supplemented groups.

• Journal of Applied Biological Chemistry
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• v.60 no.2
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• pp.149-153
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• 2017

Contamination and growth of Trichoderma, a green mold, on the oak log and wooden chip or sawdust media can severely inhibit the growth of oak mushroom. Chemicals including pesticides and antibiotics are generally not allowed for the control of green mold disease during mushroom cultivation. In this study, bacterial pathogens causing blotch disease on the oyster mushrooms were isolated and their peptide toxins were purified for the control of green mold disease. Strains of Pseudomonas tolaasii secret various peptide toxins, tolaasin and its structural analogues, having antifungal activities. These peptides have shown no effects on the growth of oak mushrooms. When the peptide toxins were applied to the green mold, Trichoderma harzianum H1, they inhibited the growth of green molds. Among the 20 strains of peptide-forming P. tolaasii, strong, moderate, and weak antifungal activities were measured from 8, 5, and 7 strains, respectively. During oak mushroom cultivation, bacterial culture supernatants containing the peptide toxins were sprayed on the aerial mycelia of green molds grown on the surface of sawdust media. The culture supernatants were able to suppress the fungal growth of green molds while no effect was observed on the mushroom growth and production. They changed the color of molds from white aerial mycelium into yellowish dried scab, representing the powerful anti-fungal and sterilization activities of peptide toxins.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.4 s.48
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• pp.503-507
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• 2004

The essential oil from Chamaecyparis obtusa was investigated for biological activities in anti-oxidative, anti-inflammation and antibacterial method, respectively. The Growth inhibitory effect of C. obtusa oil on the bacteria was evaluated with MIC (minimum inhibitory concentration), $IC_{50}\;(50\%$ inhibitory concentration), and paper disc method. Two kinds of gram positive strains and two kinds of gram negative strains were used in this study. Gram positive strains were B. subtilis and S. aureus. and Gram negative strains were E. coli and P. aeruginosa. Gram positive strains showed much more intensive effect than gram negative strains. Anti-oxidative effect was investigated with DPPH (1,1-diphenyl-2-picrylhidrazyl) in methanol based and $IC_{50}\;was\;0.78\%.$ Our results suggest that the essential oil from Chamaecyparis obtusa has effects on anti-bacterial, anti- oxidative and anti-inflammation in in vitro and in uiuo. Then this material could be expect synergic effect with other candidated extracts and oils.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.445-453
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• 2016

Eighty-four strains of lactic acid bacteria were isolated from Korean fermented foods for the production of fermented apple juice. Among these strains, the JBE245 strain that showed rapid growth and food functionality was selected and identified as Lactobacillus plantarum. This strain reached the stationary phase after 24 h fermentation at $30^{\circ}C$ with $1.5{\times}10^8$ colony forming unit (CFU)/mL of viable cells, and maintained its viability levels even after 14 days of storage. During fermentation, the ${\alpha}-glucosidase$ inhibitory activity (40.4%), total polyphenol content (583.6 mg gallic acid equivalent (GAE)/mL), and 2,2-diphenyl-l-picryl-hydrazyl hydrate (DPPH) radical scavenging activity (52%) were increased. As judged by a sensory test, the overall preference for the fermented juice (4.22) was comparable to that for the unfermented juice (4.72), indicating that fermentation does not significantly affect the sensory characteristics of apple juice. Consequently, the fermented beverage containing L. plantarum JBE245 and apple juice is a promising functional health food.

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.265-272
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• 2017

Some bacteria with different mechanisms for hydrocarbon degradation were isolated from oil-contaminated soils in Korea. Isolate Acinetobacter calcoaceticus SL1 showed biosurfactant- producing activity in oil-spreading test, and it exhibited a good emulsifying activity of 43.6 and 54.5% for diesel oil and n-hexane, respectively. It also has high cell surface hydrophobicity which can make it easily attaches to hydrocarbons and degrade them. It degraded 100% of 1,000 mg/L of n-octadecane and naphthalene, respectively in 3 days, 72.3% of 1,000 mg/L diesel oil in 7 days and 78.0% of 10,000 mg/L diesel oil in oil-contaminated soil during 28 days. Isolated strains Bacillus amyloliquefaciens S10 and B. subtilis GO9 can produce biosurfactant and formed 6.34 and 2.5 cm diameter of clear zones, respectively in oil-spreading test. Surface tension of their culture supernatant reduced from 74.6 to 34.4 and 33.3 mN/m, respectively during incubation, and critical micelle concentrations of culture supernatants were 2.0 and 5.9%, respectively. Consortium of A. calcoaceticus SL1 and B. amyloliquefaciens S10 degraded 77.8% of 10,000 mg/L diesel oil in 3 days, which indicated more efficient oil degradation than that by A. calcoaceticus SL1 alone. If these bacteria were applied together as a consortium to oil-contaminated sites, they may show a high removal rate of petroleum hydrocarbons.