• 한국식생활문화학회지
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• 제34권2호
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• pp.142-158
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• 2019

Kimchi is a traditional Korean fermented vegetable probiotic food. The use of high quality ingredients and predominant LAB (lactic acid bacteria)-whether it be ambient bacteria or adding starters, low temperature and facultative anaerobic condition for the fermentation are important factors for preparing kimchi with better taste and functionality. The predominated LAB genera are Leuconostoc, Lactobacillus, and Weissella in kimchi fermentation. The representative species are Leu. mesenteroides, Leu. citrium, Lab. plantarum, Lab. sakei, and Wei. koreensis. Kimchi, especially the optimally fermented kimchi, has various health benefits, including control of colon health, antioxidation, antiaging effects, cancer preventive effect, antiobesity, control of dyslipidemic and metabolic syndrome, etc.; due to the presence of LAB, various nutraceuticals, and metabolites from the ingredients and LAB. The kimchi LAB are good probiotics, exhibiting antimicrobial activity, antioxidant, antimutagenic and anticancer effects, as well as immunomodualatory effect, antiobesity, and cholesterol and lipid lowering effects. Thus, kimchi ingredients, LAB, fermentation methods, and metabolites are important factors that modulate various functionalities. In this review, we introduced recent information showing kimchi and its health benefits in Korean Functional Foods (Park & Ju 2018).

• 한국미생물·생명공학회지
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• 제17권1호
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• pp.24-28
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• 1989

미생물에 의해 hydrocortisone을 $\Delta$'-dehydrogenation하여 prednisolone 생산을 위한 공정에 있어 여러 발효변수들의 영향이 조사되었다. 미생물 전환공정은 pseudo-crystallo-fermentation 방법을 이용하였으며, 생물 전환을 위한 최적 온도는 35$^{\circ}C$였다. 발효배지의 초기 pH 6.5-7.8 범위에서는 prednisolone 생산에 pH의 영향이 거의 없었으며, 또한 계면활성제 Tween 80의 영향도 거의 없는 것으로 나타났다. Prednisolone의 생산속도는 소포제 neolin 을 첨가함으로써 현저하게 감소하였다. 발효조 조업시에는 높은 공기주입 속도로 인해 발생되는 기포를 제거하기 위해 많은 양의 소포제가 사용되었으며, 따라서 shake flask 조업시보다 prednisolone 생산속도가 낮은 것으로 나타났다.

• Journal of Biosystems Engineering
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• 제41권2호
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• pp.85-92
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• 2016

Background: The same plant, Camellia sinensis, is used to produce all types of tea, and the differences among the various types arise from the different processing steps that are used. Based on the degree of fermentation, tea can be classified as black, green, white, or oolong tea. Of these, black tea is the most or fully fermented tea. The oxidized polyphenolic compounds such as theaflavins (TF) and thearubigins (TR) formed during fermentation are responsible for the color, taste, flavor, and aroma of black tea. Results: Research indicates that an optimum ratio of TF and TR (1:10) is required to ensure a quality cup of tea. The concentrations of TF and TR as well as desirable quality characteristics increase as fermentation time increases, reaching optimum levels and then degrading if the fermentation time is prolonged. It is also necessary to control the environment for oxidation. There are no established environment conditions that must be maintained during the fermentation of the ruptured tea leaves. However, in most cases, the process is performed at a temperature of $24-29^{\circ}C$ for 2-4 h or 55-110 min for orthodox tea or crush, tear, and curl (CTC) black tea, respectively, under a high relative humidity of 95-98% with an adequate amount of oxygen. Conclusion: The polyphenolic compounds in black tea such as TF and TR as well as un-oxidized catechins are responsible for the health benefits of tea consumption. Tea is rich in natural antioxidant activities and is reported to have great potential for the management of various types of cancers, oral health problems, heart disease and stroke, and diabetes and to have other health benefits such as the ability to detoxify, improve urine and blood flow, stimulate, and improve the immune system.

• 산업식품공학
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• 제21권4호
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• pp.403-408
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• 2017

양파를 이용하여 식초를 제조하기 위하여 막걸리로부터 분리된 내산성과 내알코올성이 우수하고 산생성능이 높은 Aectoacter orientalis MAK88를 사용하였다. 양파 추출액에 A. orientalis MAK88의 종배양액을 접종하여 초산 발효를 실시하였을 경우, 발효 최적 조건을 조사하였다. 앙파 추출액 중의 초기 에탄올 농도는 5% (v/v)가 최적이었으며, 발효 144시간에서의 산도는 4.31%이었다. 초기 초산 농도는 1% (v/v)가 최적으로 발효 144시간에서의 최종 산도는 5.32%였다. 최적 발효온도는 $28^{\circ}C$로 확인되었다. 양파 착즙액은 통 양파를 $121^{\circ}C$에서 15분간 가열한 뒤 가압 착즙 후 여과한 다음 $121^{\circ}C$에서 15분간 살균하여 제조한 것이 발효에 가장 적합하였으며, 희석하지 않은 착즙 원액을 사용하는 것이 가장 좋았다.

• Applied Biological Chemistry
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• 제27권4호
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• pp.217-224
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• 1984

생전분질원료(生澱粉質原料)를 사용(使用)하는 ethanol발효(醱酵)에 있어서 고온성효모(高溫性酵母)의 사용효과(使用效果)를 시험(試驗)하기 위하여 분리(分離), 보존중(保存中)인 고온성효모(高溫性酵母)(T-71균주(菌株))의 생육온도(生育溫度), ethanol 내성(耐性)등의 특성(特性)을 조사(調査)하고, 몇가지 생전분질원료(生澱粉質原料)를 사용(使用)한 발효시험(醱酵試驗)을 실시(實施)하였다. 고온성효모(高溫性酵母) T-71의 생육(生育) 및 발효최고온도(醱酵最高溫度)는 $42^{\circ}C$이며, 대조균주(對照菌株)보다 $2^{\circ}C$ 이상 높았으며 ethanol함유배지(含有培地)에 효모균체(酵母菌體)를 접종(接種)하여 발효능(醱酵能)을 검토(檢討)한 바 T-71균주(菌株)는 대조균주(對照菌株)보다 ethanol 내성(耐性)이 컸다. T-71균주(菌株)의 발효최적온도(醱酵最適溫度)는 술덧의 종류(種類)와 담금 농도(濃度)에 따라 달라지나 어느 경우나 대조균주(對照菌株)에 비(比)하여 최적발효온도(最適醱酵溫度)가 높았다. 시험균주(試驗菌株)를 각각(各各)의 최적온도(最適溫度)에서 발효(醱酵)시킬 때 고온성효모(高溫性酵母) T-17을 사용(使用)한 경우는 대조균주(對照菌株)의 경우에 비하여 발효기간(醱酵期間)을 $1{\sim}2$일간(日間) 단축(短縮)시킬 수 있었다. 절간생(切干生)고구마술덧에서 T-71균주(菌株)의 최적발효온도(最適醱酵溫度)는 $35{\sim}37^{\circ}C$(생성(生成) ethanol농도(濃度) 9.6% 조건(條件))이며 $40^{\circ}C$에서도 별차이가 없었으나, 보리가루술덧과 절간고구마가루술덧에서 T-71균주(菌株)의 최적발효온도(最適醱酵溫度)는 각각(各各) $35^{\circ}C$(각(各) 생성(生成) ethanol 농도(濃度) 14.0% 및 12.8%조건(條件))이었다.

• Journal of Microbiology and Biotechnology
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• 제23권12호
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• pp.1654-1663
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• 2013

Rice straw is closely associated with meju fermentation and it is generally known that the rice straw provides meju with many kinds of microorganisms. In order to elucidate the origin of meju fungi, the fungal diversity of rice straw was examined. Rice straw was collected from 12 Jang factories where meju are produced, and were incubated under nine different conditions by altering the media (MEA, DRBC, and DG18), and temperature ($15^{\circ}C$, $25^{\circ}C$, and $35^{\circ}C$). In total, 937 strains were isolated and identified as belonging to 39 genera and 103 species. Among these, Aspergillus, Cladosporium, Eurotium, Fusarium, and Penicillium were the dominant genera. Fusarium asiaticum (56.3%), Cladosporium cladosporioides (48.6%), Aspergillus tubingensis (37.5%), A. oryzae (31.9%), Eurotium repens (27.1%), and E. chevalieri (25.0%) were frequently isolated from the rice straw obtained from many factories. Twelve genera and 40 species of fungi that were isolated in the rice straw in this study were also isolated from meju. Specifically, A. oryzae, C. cladosporioides, E. chevalieri, E. repens, F. asiaticum, and Penicillium polonicum (11.8%), which are abundant species in meju, were also isolated frequently from rice straw. C. cladosporioides, F. asiaticum, and P. polonicum, which are abundant in the low temperature fermentation process of meju fermentation, were frequently isolated from rice straw incubated at $15^{\circ}C$ and $25^{\circ}C$, whereas A. oryzae, E. repens, and E. chevalieri, which are abundant in the high temperature fermentation process of meju fermentation, were frequently isolated from rice straw incubated at $25^{\circ}C$ and $35^{\circ}C$. This suggests that the mycobiota of rice straw has a large influence in the mycobiota of meju. The influence of fungi on the rice straw as feed and silage for livestock, and as plant pathogens for rice, are discussed as well.

• 산업기술연구
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• 제3권
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• pp.87-94
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• 1983

Heating characteristics of red pepper paste packed in report pouches of various thicknesses and their storage stability were investigated to determine the adequate processing conditions that good bacteriological safty and minimal quality changes could be obtained, when sterilized by using a steam-air system retort. A heat penetration into pouch-packed red pepper paste was carried out through by a conductive heat transfer, indicating a simple logarithmic heating curve, and the smaller thickness revealed the higher heat penetration rate, suggesting the possibility of high temperature-short time sterilization of red pepper paste. The processing conditions with Fo-value of 4.5 or higher were sufficient for keeping up bacterial safty, but based on C-value, better quality retention was obtained at pouch thickness of 15mm under the processing temperature of $120^{\circ}C$. Subsequent storage study revealed that the red pepper paste packed in 15mm and processed at $120^{\circ}C$ with Fo=4.5 could be held without any spoilage and overall acceptance change, when stored for 6 months at room temperature under the relative humidity of 70%. After 3 months storage in $38^{\circ}C$ under saturation humidity, overall acceptance of red pepper paste were judged not to be maintainable on the acceptable level, but it may be suggested that above the results could be kept up a desirable quality without any remarkable deterioration.

• Journal of Animal Science and Technology
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• 제47권2호
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• pp.253-260
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• 2005

This study was conducted to utilize the wastes produced from thinning the forest as a roughage source for ruminants. Four ruminally cannulated Korean steers were used to investigate the ruminal fermentation characteristics and blood concentrations of stress-related hormones. Treatments were composed of the rice straw only (Control) and the 30% pine silage plus 70% rice straw(Pine silage) as roughages. The experiment was conducted with four replicates by a double tum over design. For sampling of blood under high temperature steers were accommodated in respiratory chamber. Concentrations of ruminal pH, volatile fatty acids and ammonia were not affected by substitution of pine silage. Mean concentration of blood thyroxine was significantly(P < 0.01) lower in the pine silage than the control. However, blood cortisol concentration was not affected by substitution of pine silage, even though it was significantly(P < 0.05) decreased after exposure for 6 hrs in high temperature. It was concluded that the pine silage using the wastes produced from thinning the forest could be use as a substitute roughage for reduction of heat stress in ruminant.

• Journal of Microbiology and Biotechnology
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• 제21권9호
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• pp.960-967
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• 2011

Tannin acyl hydrolase, also known as tannase, is an enzyme with important applications in the food, feed, pharmaceutical, and chemical industries. However, despite a growing interest in the catalytic properties of tannase, its practical use is very limited owing to high production costs. Several studies have already demonstrated the advantages of solid-state fermentation (SSF) for the production of fungal tannase, yet the optimal conditions for enzyme production strongly depend on the microbial strain utilized. Therefore, the aim of this study was to improve the tannase production by a locally isolated A. niger strain in an SSF system. The SSF was carried out in packed-bed bioreactors using polyurethane foam as an inert support impregnated with defined culture media. The process parameters influencing the enzyme production were identified using a Plackett-Burman design, where the substrate concentration, initial pH, and incubation temperature were determined as the most significant. These parameters were then further optimized using a Box-Behnken design. The maximum tannase production was obtained with a high tannic acid concentration (50 g/l), relatively low incubation temperature ($30^{\circ}C$), and unique low initial pH (4.0). The statistical strategy aided in increasing the enzyme activity nearly 1.97-fold, from 4,030 to 7,955 U/l. Consequently, these findings can lead to the development of a fermentation system that is able to produce large amounts of tannase in economical, compact, and scalable reactors.

• Journal of Microbiology and Biotechnology
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• 제22권7호
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• pp.930-938
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• 2012

High levels of xylanase activity (143.98 IU/ml) produced by the newly isolated Paenibacillus campinasensis G1-1 were detected when it was cultivated in a synthetic medium. A thermostable xylanase, designated XynG1-1, from P. campinasensis G1-1 was purified to homogeneity by Octyl-Sepharose hydrophobic-interaction chromatography, Sephadex G75 gel-filter chromatography, and Q-Sepharose ion-exchange chromatography, consecutively. By multistep purification, the specific activity of XynG1-1 was up to 1,865.5 IU/mg with a 9.1-fold purification. The molecular mass of purified XynG1-1 was about 41.3 kDa as estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Sequence analysis revealed that XynG1-1 containing 377 amino acids encoded by 1,134 bp genomic sequences of P. campinasensis G1-1 shared 96% homology with XylX from Paenibacillus campinasensis BL11 and 77%~78% homology with xylanases from Bacillus sp. YA-335 and Bacillus sp. 41M-1, respectively. The activity of XynG1-1 was stimulated by $Ca^{2+}$, $Ba^{2+}$, DTT, and ${\beta}$-mercaptoethanol, but was inhibited by $Ni^{2+}$, $Fe^{2+}$, $Fe^{3+}$, $Zn^{2+}$, SDS, and EDTA. The purified XynG1-1 displayed a greater affinity for birchwood xylan, with an optimal temperature of $60^{\circ}C$ and an optimal pH of 7.5. The fact that XynG1-1 is cellulose-free, thermostable (stability at high temperature of $70^{\circ}C{\sim}80^{\circ}C$), and active over a wide pH range (pH 5.0~9.0) suggests that the enzyme is potentially valuable for various industrial applications, especially for pulp bleaching pretreatment.