• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1479-1484
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• 2008

This study was conducted to investigate the quality characteristics of fermented-defatted soybean grits (DSG). Fermented-DSG was prepared by inoculating Bacillus subtilis NUCI into steamed DSG at 2% (v/w) concentration and fermenting at $40^{\circ}C$ for 24 hr. The protein contents of DSG and fermented-DSG were higher by $57.2{\sim}61.0%$ than those of Chungkukjang, but lipid contents of these samples were not detected. The protease and $\alpha$-amylase activities, and solid contents in DSG were not shown. However, the activities of protease and $\alpha$-amylase, tyrosine contents, fluid consistency, and viscous substance contents of fermented-DSG were higher than those of Chungkukjang. The levels of free amino acids and isoflavone of fermented-DSG tended to increase more than those of DSG. The sensory score of fermented-DSG were higher in odor and taste than those of Chungkukjang groups, while lower in color and overall acceptability.

• KSBB Journal
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• v.11 no.1
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• pp.8-14
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• 1996

Bacillus subtillis strains with transition state regulator mutations and a spore mutation were developed for the overexpression of apsE and for the enhancement of expression level. Among the many regulator genes, degU and hpr were chosen as a representative positive and negative regulator for the aprE, respectively. Spo II G was used for the construction of asporogeneous strains. All the mutants were constructed from two protease-deleted strain DB104 and the apsE gene was transformed with an integration vector pMK101. DB104(deg$U^h$(32) $his^+$)::pMK101(Cm) and DB104($\Delta$her(Em))::pMKl01(Cm) show 7-fold and about 2-fold increase in aprE expression level, respectively. But the effect of transition state regulator mutation on the aprE expression was diminished when the integrated aprE gene was amplified by the high concentration of chloramphenicol, i. e. 30 $\mu\textrm{g}$/ml. DB104($\Delta$spoIIG(Pm) degUh(32) his+)::pMK101(Cm) and DB104($\Delta$spoIIG(Pm) $\Delta$hpr(Em))::pMK101 double mutant show 10-fold and 3-fold increase in aprE expression level, respectively. The results suggest that sporulation mutation and transition state regulator mutation have independent and additive effect on the aprE expression, and the same gene dosage effect on the transition state regulator mutation was also identified.

• Journal of Life Science
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• v.26 no.12
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• pp.1409-1414
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• 2016

In the larvae of the black soldier fly, Hermetia illucens, innate immunity mechanisms are activated in response to various pathogens and stimulants, resulting in the expression of antimicrobial peptides (AMPs). To induce the mass production of AMPs, H. illucens fifth instar larvae were immunized with five different kinds of bacteria. We isolated from the hemolymph of the H. illucens larvae after bacterial challenge, and their antimicrobial activities against Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli) were measured using the inhibition zone assay. Among these five different kinds of bacteria, the hemolymph of Bacillus subtilis-challenged H. illucens larvae showed the strongest antimicrobial activity against both Gram-positive bacteria and Gram-negative bacteria. The antimicrobial activity of the hemolymph of $1{\times}10^9cfu/ml$ B. subtilis-challenged H. illucens peaks at 24 hr at 48 hr post-infection and gradually declines with time. Moreover, the immunized hemolymph also showed strong antimicrobial activity against various poultry pathogens such as S. enteritidis, S. typhimurium, and S. pullorum. These results suggest that the expression of AMP genes in B. subtilis-challenged H. illucens is up-regulated by innate immune responses, and that B. subtilis-challenged H. illucens overexpressing AMPs may be useful as a feed additive in livestock diets to reduce the need for antibiotics.

• Journal of Life Science
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• v.20 no.6
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• pp.934-939
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• 2010

We have previously reported recombinant productions of bacteriocins using yeast expression plasmid pAUR123, which contains the alcohol dehydrogenase (ADH) promoter, in Saccharomyces cerevisiae cells and their antibacterial activities. In order to improve the antibacterial activities of bacteriocidal yeast cells, a strong glyceraldehyde phosphate dehydrogenase (GPD) promoter gene of S. cerevisiae was amplified and inserted upstream into bacteriocin genes such as the OR-7, Subpeptin JM4-A or JM4-B gene in the corresponding recombinant yeast plasmid. Yeast cells transformed by the recombinant plasmid containing the GPD promoter represented higher antibacterial activities against both Gram positive B. subtilis and Gram negative E. coli cells compared to those transformed by the corresponding recombinant plasmid containing the ADH promoter. Thus, yeast cells harboring the recombinant plasmid containing the GPD promoter constructed in this study could be applied in the food preservative or animal feed industries.

• The Journal of Korean Medicine
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• v.19 no.1
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• pp.89-99
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• 1998

약효(藥效) 및 안정성(安定性)이 입증(立證)된 한약(韓藥)으로부터 새로운 항균제(抗菌劑)를 도출(導出)하고자, 임상(臨床)에서 청열작용(淸熱作用)이 있거나 염증성(炎症性) 질환(疾患)과 박테리아의 감염(感染)으로 비롯된 질환(疾患)에 자주 쓰이는 22개(個)의 처방(處方)에 대(對)해 paper disk 법(法)을 사용(使用)하여 항균(抗菌) 효능(效能)을 검색(檢索)하였다. 시료(試料)는 한약(韓藥)의 고용(股用) 방법(方法)을 고려(考慮)하여 물로 추출(抽出)하였으며, 사용(使用) 균주(菌柱)로는 그람 양성균(陽性菌)인 포도상구균(葡萄狀球菌)과 고초균(枯草菌) 그리고 그람 음성균(陰性菌)인 대장균(大腸菌)과 녹농균(綠膿菌)을 사용(使用)하였고, 대조물질(對照物質)로는 tetracycline을 사용(使用)하여 상법(常法)에 의(依)해 실험(實驗)하였다. 22개(個)의 처방(處方) 가운데 백두옹탕(白頭翁湯), 황연해독탕(黃連解毒湯), 증황연황연해독탕(增黃連黃連解毒湯), 사심탕(瀉心湯), 용담사간탕(龍膽瀉肝湯), 선방활명음(仙方活命飮) 등(等)의 처방(處方)이 탁월(卓越)한 항균(抗菌) 활성(活性)을 보였다. 이 가운데 본(本) 연구(硏究)에서는 탕제(湯劑)의 구성(構成) 약재(藥材)가 다른 처방(處方)들에 비(比)해 비교적(比較的) 다양(多樣)한 선방활명음(仙方活命飮)에 대(對)해 활성(活性) 성분(成分)의 규명(糾明) 및 구성(構成) 약재간(藥材間)의 상화작용(相互作用)을 밝히고자 하였다. 선방활명음(仙方活命飮) 5 kg을 메탄올 (MeOH)로 추출(抽出)한 뒤 우수(優秀)한 항균(抗菌) 활성(活性)을 보인 에칠아세테이트 (EtOAc) 분획(分劃)에 대(對)하여 silica gel 및 Sephadex LH-20 column chromatography를 반복(反復)하여 stilbene 계열(系列)의 화합물(化合物)인 Rhapontigenin (Compound 1)과 Rhaponticin (Compound 2)을 얻었다. S. aureus SG 511에 대(對)해 Rhapontigenin은 50 mg/ml 이상(以上) 농도(濃度)에서 항균(抗菌) 효과(效果)를 나타내었고, Rhaponticin은 $200\;mg/m{\ell}$ 농도(濃度)에서 미약(微弱)하게 유효(有效)한 항균(抗菌) 효과(效果)를 나타내었으며, B. subtilis ATCC 6633에 대(對)해 Rhapontigenin은 50 mg/ml 이상(以上) 농도(濃度)에서 항균(抗菌) 효과(效果)를 나타내었고, Rhaponticin은 200 mg/ml 농도(濃度)에서 우수(優秀)한 항균(抗菌) 효과(效果)를 나타내었으며, 100 mg/ml 농도(濃度)에서 미약(微弱)하게 유효(有效)한 항균(抗菌) 효과(效果)를 나타내었다. 또한 E. coli 055에 대(對)해서는 Rhapontigenin과 Rhaponticin 모두 200 mg/ml 농도(濃度)에서 미약(微弱)하게 유효(有效)한 항균(抗菌) 효과(效果)를 나타내었다. 이상(以上)의 결과(結果)로 보아 선방활명음(仙方活命飮)의 항균(抗菌) 효능(效能)은 군약(君藥)인 대황(大黃)의 성분(成分) 중(中)의 하나인 stilbene 계열(系列)의 화합물(化合物)인 Rhapontigenin과 Rhaponticin의 작용(作用)에 의(依)한 것이며, 이는 한의학(韓醫學) 방제(方劑) 원리(原理)인 군신좌사(君臣佐使) 이론(理論)에서 군약(君藥)이 주증(主症)에 주(主)로 작용(作用)하는 약물(藥物)이라는 것을 밝혀주는 것이라고 사료(思料)된다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.8
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• pp.1070-1076
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• 2007

Soymilk cake (SMC) fortified with defatted soy flour was fermented by a novel Bacillus subtilis GT-D in the solid-state fermentation with chlorella, mulberry leaves or green tea as food ingredient. The fermentation of SMC resulted in higher content of tyrosine and higher activities of protease, amylase and fibrinolytic enzymes. Fermented SMC including mucilage indicated six-fold higher content of dietary fiber compared to that of non-fermented SMC. The SMC fermented without additional ingredient allowed the highest spread ratio and width of cookies. Cookies prepared without SMC showed the lowest value of spread ratio and width compared to those of fermented SMC. In addition, these cookies showed the highest hardness value of 8,975 g, and thickness value of 5.97 and slightly higher bright color. Cookies fortified with SMC fermented with chlorella or mulberry leaves showed higher sensory evaluation value. Fortification of SMC fermented without additional ingredient resulted in the highest preference in the sensory evaluation of cookies.

• KSBB Journal
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• v.25 no.6
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• pp.520-526
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• 2010

In this work we have investigated the production of catalase from Bacillus sp. strains, which were screened and identified from soil. These strains were cultivated in shaking flasks with tryptic soy broth (TSB) at $30^{\circ}C$ and 200 rpm. Effects of the temperature and pH on the stability of the native catalase and whole cell viability were studied in the temperature range of $25-60^{\circ}C$ and the pH range of 7-13. Korean natural zeolite was added to culture medium and mixed with microorganisms for 24 hours. The native catalase maintained its activity over $50^{\circ}C$. The enzyme acitiviy of the catalase from Bacillus flexus BKBChE-3 was highest among the Bacillus sp. strains studied. Bacillus flexus BKBChE-3 and immobilized Bacillus cells have survived under extreme conditions of over $50^{\circ}C$ and pH 12. 60 mL of 10.5 mM $H_2O_2$ solution were entirely removed within 1 hour with catalase produced from Bacillus sp. on the flask. When Bacillus cells were immobilized on Korean natural zeolite, colony forming unit of Bacillus flexus BKBChE-3 was increased and high efficiency of hydrogen peroxide removal was observed.

• Food Science and Preservation
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• v.24 no.1
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• pp.134-144
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• 2017

This study evaluated the changes of physiochemical properties, phytochemical compounds (isoflavones and phenolic acids), and biological activity during the fermentation of Doenjang without and with bitter melon powder (BMP). The pH decreased from 6.41-5.83 to 5.81-5.24, during the fermentation of Doenjang, while the acidity increased from 0.42-0.65% to 1.28-1.48%. The viable cell numbers of Bacillus and Yeast, salinity, and total amino acid contents increased at the end fermentation (60 day). Also, the fermented Doenjang (FD) with 10% BMP showed the highest ${\gamma}$-aminobutyric acid (GABA, 129.87 mg/100 g) contents, among all the Doenjang samples. The FD exhibited significantly higher inhibitory activities than unfermented Doenjang (UFD) on radicals and ${\alpha}$-glucosidase. The phytochemical compounds including isoflavone-aglycones and phenolic acids increased, whereas isoflavoneglycosides decreased in the BM following fermentative processing. Moreover, the total phenolic, isoflavone-aglycone, and phenolic acid contents were markedly increased, leading to a general increase in antioxidant and ${\alpha}$-glucosidase inhibition activities after fermentation. These results suggest that BMP may be used to prepare a new type of fermented Doenjang with improved antioxidant and antidiabetic activities.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.6
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• pp.657-662
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• 2009

Antioxidant and anticancer activities of water and ethanol extracts of defatted soybean grits (DSG) fermented Bacillus subtilis NUC1 were determined and compared with those of the raw DSG. The fermented defatted soybean grits (FDSG) exhibited higher total polyphenols and flavonoids contents than DSG. The ethanol extracts of FDSG (FD-E) showed the highest polyphenol and flavonoid contents with 23.35 mg/g and 3.48 mg/g, respectively. Particularly, FD-E showed higher DPPH radical scavenging activities with $RC_{50}$ of 0.32 mg/mL than other samples with $RC_{50}$ of 1.10${\sim}$3.89 mg/mL. The water and ethanol extracts of FDSG and DSG showed growth inhibitory effects against AGS, A549 and Hela cancer cells in a dose-dependent manner, and especially FD-E showed the highest growth inhibition effects. FD-E induced apoptosis in Hela cells through an increased activation of caspase-3 and caspase-3 target protein, PARP, but rarely affected caspase-7.

• Food Engineering Progress
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• v.15 no.1
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• pp.22-27
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• 2011

Changes in total nitrogen (T.N.) and total phosphate (T.P.) content in environmental waste water upon the reaction of biological purifying reagents were measured and the reaction rate was evaluated. The purification capacity of two biological purifying reagents composed of vegetable Lactobacillus fermentum (V.L.F.), Saccharomyces cerevisiae(S.C), and Bacillus subtilis(B.S.) were evaluated and compared with that of commercial water purification system operating by local government. After 18days of reaction, the mixture of V.L.F. and S.C. showed dramatic decrease of T.N.(36.21% of the initial value). The mixture of V.L.F., S.C., and B.S. showed faster reaction rate to decrease T.P. compared with that of the mixture of V.L.F. and S.C. The reaction constant of mixture of V.L.F. and S.C. was estimated to be 0.178 $day^{-1}$ by the curve fitting of the data of changes in T.N. during the reaction.