• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.495-501
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• 2011

Bacterial strains were isolated from forest soils of Halla mountain, Jeju island in Korea. The soil samples were collected at each altitude of 100m from 1,000 m above sea level. Total 398 strains were isolated and tested for their physiological characteristics of antagonistic and proteolytic activities, and auxin production. Among the isolates, 172 strains were selected as antifungal strains showing antagonistic activity against at least one of 8 plant fungal pathogens (Alternaria alternata, Botrytis cinerea, Collectotrichum acutatum, Fusarium oxysporum, Phytophthora capsici, Pythium ultimum and Sclerotinia sclerotiorum). In addition 203 strains for proteolytic activity and 26 strains for auxin production were characterized for further study. Je28-4 (Rhodococcus sp.) were showed 80% of control value against tomato gray mold in vivo. Thus, it is suggested that soil bacteria isolated from forest soils of Halla mountain can be important sources of bioactive compounds for improving plant growth or promising biocontrol agents.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.7
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• pp.752-756
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• 2006

The independent anoxic reactor was introduced in biological aerated filters as the regulation of water quality requirement, especially total nitrogen, had been strengthened. The process studied in this work was upflow $Biobead^{(R)}$ process which was used commercial invented for removal of organic materials and nitrification. For the purpose of evaluating the independent anoxic reactor, PCR-DGGE, of the molecular biological methods, was performed. Two types of nitrite reductase genes were selected. One is nirS represented cytocrome $cd_1$ nitrite reductase gene and the other is nirK represented Cu-containing nitrite reductase gene. Denitrifier community in the independent anoxic reactor was analyzed with PCR-DGGE using these two denitrifying functional genes. As the result of the PCR, only nirS gene was detected between nirS and nirK. With the result of the DGGE, specific bands became strong, as the operating days were longer, nitrate loading rate was increased. otherwise those of the initial activated sludge showed various bands. In the consequence of the sequence of DGGE bands, various denitrifiers were sequenced in the initial activated sludge, while specific denitrifiers like alcaligenes faecalis were predominant in the anoxic reactor. Consequently, introduction of the independent anoxic reactor made it possible to achieve 96% denitrification efficiency, and was proper for the modification of BAF process.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.792-798
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• 2002

Investigations on the microbiological, physicochemical, and sensory characteristics of seasoned Galbi using various packaging methods during storage at $-1^{\circ}C$ revealed no significant differences in pH values and acidities of seasoned Galbi depending on packaging methods and storage periods. Increments of thiobarbituric acid values of seasoned Galbi with non-evacuated packaging and modified atmosphere packaging were superior to those of vacuum packaging and double-film vacuum packaging during storage. Seasoned Galbi with non-evacuated packaging showed the highest volatile basic nitrogen value, and total plate count significantly increased compared to other packaging methods after 15 days storage. Coliform bacteria showed an average count of 2.35 log CFU/g at the beginning of storage, which increased slightly from 7 to 15 days, and was maintained under 4.0 log CFU/g after 15 days storage. The sensory evaluation revealed that non-evacuated packaging scored relatively lower than other methods in color, flavor, off-odor, and overall acceptability after storage.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.11-14
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• 2005

White radish was minimally processed, packed with air, $CO_{2}$ (100%), and $CO_{2}/N_{2}$ (25/75%), and irradiated at 0, 1, and 2 kGy, and its microbiological quality and pH were investigated during storage for 2 weeks at $4^{\circ}C$. Irradiation significantly reduced total aerobic, coli-form, and lactic acid bacteria counts. Modified atmosphere packaging (MAP) enhanced microorganism control during storage. Acidity decreased by MAP but was restored during storage, Irradiation did not affect sample pH. Results show irradiation at 2 kGy combined with MAP can enhance microbiological safety and quality of minimally processed radish.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.196-203
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• 2002

Effect of different levels (0 ,0.05, 0.15, 0.25%) of xanthan gum on kakdugi fermentation was investigated by analyzing physicochemical and sensory characteristics during fermentation at 2$0^{\circ}C$. During fermentation, pH was maintained higher, and total acidity and number of lactic acid bacteria, maintained lower in xanthan gum groups, especially in 0.05% addition group than control. Free sugar amount were higher in xanthan gun groups than control, and glucose and fructose which were the major free sugars, decreased rapidly during fermentation, whereas mannitol increased in all samples, especially in xanthan gum groups. Liquid content of kakdugi was smaller in 0.05% xanthan gum group than control. Viscosity of kakdugi liquid decreased rapidly whereas initial viscosity was maintained in xanthan gum groups. Hardness decreased during fermentation, but at the 7th day of fermentation was higher in 0.05% xanthan gum group than control. The result of sensory evaluation shows that there were no significant difference in sour odor, moldy, sour taste and savory taste among samples. Starch taste was higher in 0.15% or 0.25% xanthan gum, but there is no difference in 0.05% group, compared to control. Overall preference until the 5th day of fermentation, xanthan gum group was not significantly different from that of control but at the 7th day of fermentation, 0.05% addition group was significantly higher than control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.2
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• pp.161-166
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• 2003

This study attempted to fortify Kimchi with water extracts of shells of shellfishes (corb shell, short neck clam, taste clam, ark shell, top shell, oyster) as natural resource of calcium. Kimchi added with the shell extracts in 5% were fermented at 1$0^{\circ}C$ with measurements in chemical, microbiological and sensory qualities. Calcium content of shellfish shells before water extraction was in the range of 25.57~38.78%. Kimchi added with the extracts showed higher pH, lower acidity, lower total aerobic bacterial count and higher lactic acid bacteria count compared to control Kimchi without any addition. After 7 day fermentation the Kimchi added with the extracts also showed higher ash and calcium contents compared to control products (3.3~5.0 vs. 2.8~3.0% and 300~376 vs. 70~95 mg%). Kimchi with oyster shell extract gave the most pronounced effect in ash and calcium contents. The addition of extract made Kimchi crisper and less sourer oganoleptically. In the overall acceptability, the Kimchi fortified with the shell extracts were better than control after 14 day fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1245-1252
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• 2003

A starter formulation was developed to substitute a baker's yeast with natural starter when manufacturing bread products. To develop an active starlet, starter was formulated varying with types of wheat flours, level of water contents and various nutrients. Activities of starter were investigated in terms of viable counts of microbes and change of pH and total titratible acidity Domestic wheat flours contain 100 times more number of lactic acid bacteria than yeast regardless of types of wheat flours. The more protein contents in wheat flours, the more stable microbes in starter. This was considered to be the result of buffering effect of wheat proteins. The optimum level of protein content to ensure the activity of starter was more than 12.0%. Optimum level of water content in active starter was 110% based on strong flour. The more water or the less water had the tendency of decreasing viable counts of microbes. Addition of salt and sucrose had increased the activity of starters. However oligosaccharides did not affect the activity of starter. The optimum concentrations of salt and sucrose were 1.0% and 5.0% respectively. Bread with the starter was higher scored than breads with yeast in terms of all the quality and sensory characteristics except their volumes. In conclusion, a starter formulated with strong flour 100%, water 110%, salt 1% and sucrose 5% was considered to have high potential as a substitute of yeast in making natural bread.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.915-920
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• 2007

Rice flour milled from spray-washed rice was stored at $5^{\circ}C$, $20^{\circ}C$, and $35^{\circ}C$ for 4 months and changes in flour properties during the storage were investigated. Moisture content of rice flour tended to decrease during the storage, and the reduction in the moisture content was higher at higher storage temperature. Compared to dry-milled rice flour, lightness of the rice flour milled from spray-washed rice was slightly higher and tended to increase slightly during the storage. Rapid Visco-Aanlyzer (RVA) peak viscosity of rice flour milled from spray-washed rice was higher throughout the storage period, compared to dry-milled rice flour. The RVA peak viscosity was lower in the order of rice flour stored at $5^{\circ}C$, $20^{\circ}C$, and $35^{\circ}C$. Little changes in setback viscosity were observed in rice flour stored at $5^{\circ}C$ and $20^{\circ}C$, while an increase in the setback viscosity was found in rice flour stored at $35^{\circ}C$. Total bacteria count was consistently lower in the rice flour milled from spray-washed rice, suggesting that spray-washing prior to milling could lower microbial growth of rice flour during storage.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.69-69
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• 2018

아로니아(Aronia czarna)는 anthocyanin, polyphenol, flavonoid, cathechine, chlorogenic acid와 같은 생리활성물질이 풍부하게 존재하며 항산화, 항암, 항균, 피부건강개선, 노화방지 등 다양한 생리활성에 대한 효능이 있는 것으로 알려져 있어 건강 및 기능성식품, 화장품 등의 원료 소재로 각광받고 있다. 생물전환(Bioconversion)은 미생물 또는 효소의 생물학적 촉매 반응을 활용하여 기존 소재의 성분을 변환시키는 기술이다, 최근 생물전환을 활용한 천연소재의 생리활성 물질 기능성, 생체이용률, 안전성을 증대시키기 위한 방안으로 많은 연구가 진행되고 있으며 식품, 의약품, 화장품 등 다양한 분야에서 활성화 되고 있다. 본 연구는 젓갈로부터 분리한 균주를 유전학적 특성을 확인하기 위하여 16S rDNA 염기서열을 분석한 뒤 그중 유산균을 발효공정에 활용하였다. 전북 순창에서 수확된 아로니아 분말과 발효공정을 수행하였으며 아로니아 최적 추출조건 선정, 발효공정 전 후 추출물의 기능성 평가를 진행하기 위하여 DPPH radical scavenging activity, Total polyphenol 함량을 확인하여 항산화 효능 및 유효성분 함량을 평가하였다. 또한 대식세포인 Raw 264.7을 사용하여 MTT assay, Nitric oxide (NO) 생성 억제 효능을 확인하여 세포독성 및 항염증 활성을 평가하였다. 실험결과, 젓갈류 발효물로부터 16종의 다양한 균주를 확보하였으며, 그중 L. rhamnosus, L. plantarum, P. pentosaceus 균을 발효 공정에 활용하여 유용 균주를 선정 결과 P. pentosaceus 종 유산균 처리군에서 무처리군 대비 DPPH radical 소거능 및 polyphenol 함량이 증가됨을 확인하였다. 발효공정 후 항산화 활성은 무처리군 대비 약 119%, polyphenol의 함량은 무처리군 대비 약 119%로 증가됨을 확인되었다. 또한 Raw 264.7 세포실험 결과 발효공정 후 독성활성이 감소되는 경향을 확인되었으며, 항염증 활성이 월등히 증가됨을 확인하였다.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.64-64
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• 2018

생물전환(Bioconversion)은 천연소재의 기능성을 증대시키기 위한 방안으로 많은 연구가 진행되고 있으며 다양한 산업에서도 활용되고 있어 유용미생물을 기반 차세대 기술로 각광받고 있다. 이러한 기술의 도입은 식품은 물론 의약품 및 화장품 산업에서도 활발히 사용되고 있으며, 특히 최근 기능성 제품에 대한 소비가 급증함에 따라 그 중요성이 높아지고 있다. 산초(Zanthoxylum schinfolium)는 limonene, citronellal, phellandrene 등의 다양한 유효물질을 함유하고 있으며 유효성분들로부터 유래되는 항산화 활성과 항암활성, 항균활성 등의 효능을 지니는 것으로 보고된바 있다. 본 연구의 생물전환 공정에 사용된 유산균들은 전통 발효식품으로 알려진 다양한 젓갈류로부터 분리하였으며, 16S rDNA 염기서열 분석을 통해 유전학적 특성을 확인하였다. 또한 확보된 유산균들을 사용하여 산초(전북 진안군) 분말의 발효공정을 수행하였으며, 산초의 최적 추출조건을 선정하고 추출물을 제조하여 생물전환 공정 전 후 활성의 변화추이를 관찰하였다. 추출물의 활성평가는 항산화 효능 및 유효성분 함량을 평가하기 위하여 DPPH radical scavenging activity와 total polyphenol 함량을 평가하고 세포주를 활용해 MTT assay, Nitric oxide(NO) 생성억제 효능을 확인하여 세포독성 및 항염증 활성을 확인하였다. 실험결과, 생물전환 공정에 사용할 유용 미생물을 확보하기 위한 실험을 통해 다양한 젓갈류에서 다양한 미생물을 확보할 수 있었으며 약 16종의 유산균을 분리하였다. 분리된 미생물을 사용하여 산초 분말의 생물전환 공정을 실시한 결과, 5종의 유용미생물 처리에서 무처리 대비 DPPH radical 소거능 및 polyphenol 함량이 유의적으로 증가됨을 확인할 수 있었다. 그 중 가장 높은 활성을 나타내는 균주를 16S rDNA 염기서열 분석을 통해 확인한 결과 Weissella confusa D1로 확인되었다. 선별 균주를 활용한 생물전환 공정 후 항산화 활성은 대조군 대비 약 120%의 활성을 나타냈으며, polyphenol의 함량은 약 126%로 증가하는 것을 확인할 수 있었다. 더 나아가 생물전환 공정 후 산초추출물의 세포독성은 처리전과 비교하여 월등히 감소하는 경향을 확인할 수 있었으며, 항염효능 또한 증가하는 경향을 나타내는 것이 확인되었다.