• Asian-Australasian Journal of Animal Sciences
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• 제30권11호
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• pp.1612-1619
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• 2017

Objective: The objective of this study was to optimize ultrasonic-assisted enzymatic hydrolysis conditions, including enzyme-to-substrate (E/S) ratio, pH, and temperature, for producing porcine liver hydrolysates (PLHs) with the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity by using response surface methodology (RSM). Methods: The study used RSM to determine the combination of hydrolysis parameters that maximized the antioxidant activity of our PLHs. Temperature ($40^{\circ}C$, $54^{\circ}C$, and $68^{\circ}C$), pH (8.5, 9.5, and 10.5), and E/S ratio (0.1%, 2.1%, and 4.1%) were selected as the independent variables and analyzed according to the preliminary experiment results, whereas DPPH free radical scavenging activity was selected as the dependent variable. Results: Analysis of variance showed that E/S ratio, pH, and temperature significantly affected the hydrolysis process (p<0.01). The optimal conditions for producing PLHs with the highest scavenging activity were as follows: E/S ratio, 1.4% (v/w); temperature, $55.5^{\circ}C$; and initial pH, 10.15. Under these conditions, the degree of hydrolysis, DPPH free radical scavenging activity, ferrous ion chelating ability, and reducing power of PLHs were 24.12%, 79%, 98.18%, and 0.601 absorbance unit, respectively. The molecular weight of most PLHs produced under these optimal conditions was less than 5,400 Da and contained 45.7% hydrophobic amino acids. Conclusion: Ultrasonic-assisted enzymatic hydrolysis can be applied to obtain favorable antioxidant hydrolysates from porcine liver with potential applications in food products for preventing lipid oxidation.

• 한국축산식품학회지
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• 제26권1호
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• pp.15-19
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• 2006

The aim of this study was to determine the best processing conditions for producing of dried lean pork as a ready-to-serve product without using large-scale machines. Lean pork sausage was produced using 1.27% sodium chloride, 0.075% sodium polyphosphate, 0.06% sodium ascorbate, 0.075% sodium pyrophosphate, 0.009% sodium nitrite, 0.009% dextrin, 0.11% sodium glutamate and 1.4% spice mixture. The most appropriate slice thickness for drying was examined by slicing the sausage at a 0.5, 1 and 2 cm thickness. The drying temperatures were determined by drying the sausage slices at 35, 48 and $68^{\circ}$. The total drying period was for 12 hr, In order to examine the ability of this process to sterilize the pork, the raw meat materials were inoculated with Escherichia coli (E. coli). The optimal conditions for producing lean pork sausages were a 2 cm slice thickness and drying temperature of $68^{\circ}C$ for 12 hr, The moisture content water activity, color, hardness and pH were measured in the dried product. The product had a moisture content of 47.5% and a water activity of 0.93. There was a 47.7% percentage reduction in moisture. The dried product tested negative for E. coli even though the raw meat materials been inoculated with E. coli.

• The Plant Pathology Journal
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• 제29권2호
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• pp.125-135
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• 2013

In agro-ecosystems worldwide, some of the most important and devastating diseases are caused by soil-borne necrotrophic fungal pathogens, against which crop plants generally lack genetic resistance. However, plants have evolved approaches to protect themselves against pathogens by stimulating and supporting specific groups of beneficial microorganisms that have the ability to protect either by direct inhibition of the pathogen or by inducing resistance mechanisms in the plant. One of the best examples of protection of plant roots by antagonistic microbes occurs in soils that are suppressive to take-all disease of wheat. Take-all, caused by Gaeumannomyces graminis var. tritici, is the most economically important root disease of wheat worldwide. Take-all decline (TAD) is the spontaneous decline in incidence and severity of disease after a severe outbreak of take-all during continuous wheat or barley monoculture. TAD occurs worldwide, and in the United States and The Netherlands it results from a build-up of populations of 2,4-diacetylphloroglucinol (2,4-DAPG)-producing fluorescent Pseudomonas spp. during wheat monoculture. The antibiotic 2,4-DAPG has a broad spectrum of activity and is especially active against the take-all pathogen. Based on genotype analysis by repetitive sequence-based-PCR analysis and restriction fragment length polymorphism of phlD, a key 2,4-DAPG biosynthesis gene, at least 22 genotypes of 2,4-DAPG producing fluorescent Pseudomonas spp. have been described worldwide. In this review, we provide an overview of G. graminis var. tritici, the take-all disease, Pseudomonas biocontrol agents, and mechanism of disease suppression.

• 한국식품과학회지
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• 제35권1호
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• pp.111-114
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• 2003

공역리놀레산(CLA)은 항암, 항산화작용, 콜레스테롤저하 등의 효과를 지닌 물질로 알려져 있으며, 일본과 미국에서는 건장보조식품으로 널리 이용되고 있다. 본 연구에서는 CLA 생산능력이 있는 미생물을 김치제조 시에 스타터로 첨가하여 김치의 맛에는 변화를 가져오지 않으면서 CLA를 생산하는 최적조건을 밝히기 위해 혐기성 스타터 비피도박테리아를 배양액상태, 냉동건조된 상태, 캡슐화된 상태 등의 세가지 형태로 접종하였다. 이들 세가지 접종 방법 중 캡슐화된 상태로 스타터를 접종 시에 김치발효 중의 박테리아의 CLA 생산능력이 최적상태로 유지되었다. 김치 제조시에 부재료로 첨가되는 고추에는 상당량의 리놀레산(LA)이 함유되어 있음이 확인되어 추가로 LA를 첨가하지 않았다. 캡슐화된 비피도박테리아 스타터를 접종한 후 김치의 맛과 CLA생산 추이를 살펴본 결과 김치 맛에 영향을 끼치지 않고 CLA를 생산할 수 있는 최적의 접종량은 0.1%(w/w)임이 밝혀졌다.

• Archives of Pharmacal Research
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• 제26권12호
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• pp.1087-1095
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• 2003

Betulinic acid (BA), a pentacyclic triterpene isolated from Lycopus lucidus, has been reported to be a selective inducer of apoptosis in various human cancer and shown anti-inflammatory and immunomodulatory properties. We postulated that BA modulates the immunomodulatory properties at least two groups of protein mediators of inflammation, interlukin-1$\beta$ (IL-1$\beta$) and the tumor necrosis factor- $\alpha$ (TNF-$\alpha$) on the basis of the critical role of the monocytes and tissue macrophages in inflammatory and immune responses. TNF-$\alpha$ and IL-1$\beta$ were produced by BA in a dose dependent manner at concentration of 0.625 and 10 $\mu$g/mL. The production of NO associated with iNOS was inhibited when treated with LPS at the concentration of 2.5 to 20 $\mu$g/mL of BA whereas COX-2 expression was decreased at 2.5 to 20 $\mu$g/mL. These modulations of inflammatory mediators were examined in LPS-stimulated RAW 264.7 cells and peritoneal macrophages. The morphology of macrophage was also examined and enhanced surface CD 40 molecule was expressed when treated BA at 0.625∼5 $\mu$g/mL with or without LPS. Furthermore, BA (20 $\mu$g/mL) enhanced apoptosis by producing DNA ladder in the RAW 264.7 cells. Our results indicated that BA induced activation of macrophage and pro-inflammatory cytokines. This may provide a molecular basis for the ability of BA to mediate macrophage, suppress inflammation, and modulate the immune response.

• Journal of Microbiology and Biotechnology
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• 제28권8호
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• pp.1360-1366
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• 2018

The fungi associated with termites secrete enzymes such as laccase (multi-copper oxidase) that can degrade extracellular wood matrix. Laccase uses molecular oxygen as an electron acceptor to catalyze the degradation of organic compounds. Owing to its ability to transfer electrons from the cathodic electrode to molecular oxygen, laccase has the potential to be a biocatalyst on the surface of the cathodic electrode of a microbial fuel cell (MFC). In this study, a two-chamber MFC using the laccase-producing fungus Galactomyces reessii was investigated. The fungus cultured on coconut coir was placed in the cathode chamber, while an anaerobic microbial community was maintained in the anode chamber fed by industrial rubber wastewater and supplemented by sulfate and a pH buffer. The laccase-based biocathode MFC (lbMFC) produced the maximum open circuit voltage of 250 mV, output voltage of 145 mV (with a $1,000{\Omega}$ resistor), power density of $59mW/m^2$, and current density of $278mA/m^2$, and a 70% increase in half-cell potential. This study demonstrated the capability of laccase-producing yeast Galactomyces reessii as a biocatalyst on the cathode of the two-chamber lbMFC.

• KSBB Journal
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• 제22권2호
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• pp.114-118
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• 2007

제주도 토양 샘플에서 분리한 amylase 생산균 15번 균주는 100 mL flask level와 10 L 생물반응기에서 T. inhamatum KSJ1의 FPpase, amylase 효소활성과 거의 비슷하였으며, flask level에서 두 균주의 xylanase, avicelase, CMCase, Gluco-amylase, $\beta$-amylase의 효소활성 및 음식물쓰레기의 당화능력도 모두 거의 비슷하였다. 두 균주를 YMEA 고체배지와 광학현미경으로 그 형태학적 특징을 관찰한 결과 T. inhamatum KSJ1이 녹색빛을 띠는 것과는 달리 amylase 생산균 15번 균주는 황색빛을 띠는 사상균으로 확인되었으며, 두 균주는 동일한 균은 아니지만 동일한 속으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제22권2호
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• pp.256-263
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• 2012

A strain of bacterium producing antifungal antibiotic was isolated and identification of the strain was attempted. We could identify the bacterium as being a Bacillus sp., based on morphological observation, physiological characteristics, and 16S rDNA sequence analysis, thus leading us to designate the strain as Bacillus sp. AH-E-1. The strain showed potent antibiotic activity against phytopathogenic and human pathogenic fungi by inducing mycelial distortion and swelling and inhibiting spore germination. The antibiotic metabolite produced by the strain demonstrated excellent thermal and pH (2-11) stability, but was labile to autoclaving. From these results, we could find a broader antifungal activity of Bacillus genus. Isolation and characterization of the active agent produced by the strain are under progress.

• Applied Biological Chemistry
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• 제41권7호
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• pp.496-499
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• 1998

Caffeine으로부터 theobromine을 생산하기 위하여 토양으로부터 theobromine 생산능력이 있는 5종의 균주를 선별하였다. 그들 중 CT-017 균주가 theobromine 생산능력이 가장 우수하였으며 Pseudomonas sp.로 부분동정되었다. Theobromine 생산에 있어서, 탄소원과 질소원으로는 5 g/l fructose와 5 g/l beef extracts가 가장 우수하였으며, 0.02 g/l $Fe^{2+}$, threonine 1.0 g/l을 사용하였을 때 가장 효과적이었다. 최적배양온도 및 초기 pH는 각각 $28^{\circ}C$ 및 6.5이었다. 상기의 최적조건하에서, 23시간 배양하였을 때, 15 g/l caffeine으로부터 7.98 g/l의 theobromine이 생산되었으며 이때의 전환율은 53.2% 이었다.

• 한국식품위생안전성학회지
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• 제36권5호
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• pp.440-446
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• 2021

GABA는 식물, 동물 및 미생물 등 자연계에 다양하게 존재하고 있으며, 항고혈압, 이뇨, 진정, 수면유도 및 항스트레스 등 다양한 효과가 있는 것으로 알려져 있어서 식품, 의약품 소재로 활용되고 있다. 본 연구에서는 김치로 부터 분리한 GABA 형성 유산균을 옥수수 수염 추출물에 적용하여 발효 특성과 발효물의 항산화 효과에 대해 분석하였다. 신규 L. plantarum LAB459의 분리와 동정은 생화학적 특성, 당자화성 및 16s rRNA 염기 서열 분석을 통해 확인되었다. 그리고 TLC와 HPLC 분석을 통해 분리된 L. plantarum LAB459가 GABA 생성능이 있는 것으로 나타났다. 그리고 탈지유가 포함된 옥수수 수염 열수 추출물에 대해 발효를 수행한 결과, 동결 건조된 발효물에 약 1 ㎍/mg 수준의 GABA가 형성된 것을 확인하였다. 또한 발효물에 대한 플라보노이드와 항산화 분석은 옥수수 수염 열수 추출물에 비해 더 높은 것으로 나타났다. 따라서 본 연구에서 분리된 L. plantarum LAB459는 다양한 식품 발효의 스타터 또는 식품 소재와 의약품 소재로 적용이 가능할 것으로 판단된다.