• 한국식품영양과학회지
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• 제45권8호
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• pp.1214-1220
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• 2016

남부 평야지에서 생산된 유색미의 품종별 항산화 성분으로 총폴리페놀, 총플라보노이드 및 안토시아닌을 분석하고 항산화 활성을 측정한 결과를 비교하였다. 총폴리페놀 함량은 흑미> 적미> 녹미 순이었고, 흑미 중에서도 흑진주, 조은흑미, 신토흑미 등이 높았다. 총플라보노이드 함량은 유색미 종류에 따른 차이보다는 품종별로 차이가 있었다. 흑진주와 홍진주, 건강홍미 등이 높은 결과를 나타내었다. 안토시아닌 함량은 적미와 녹미에서는 나타나지 않았고, 흑미에서는 신토흑미, 흑진주, 청풍흑찰 순으로 높은 결과를 보였다. ABTS 라디칼 소거능은 흑진주의 $IC_{50}$ 값이 낮아 항산화 활성이 높았고, 신토흑미, 신농흑찰, 홍진주, 적진주, 조생흑찰 등이 높았다. DPPH 라디칼 소거능에서는 흑진주의 $IC_{50}$ 값이 가장 낮았고, 건강홍미, 신토흑미가 다음으로 낮은 $IC_{50}$ 값을 보여 항산화 활성이 높았다. 총폴리페놀, 총플라보노이드, 안토시아닌 함량이 높은 흑미인 흑진주는 가장 높은 항산화 활성을 나타내었다. 총폴리페놀과 총플라보노이드 함량이 낮은 녹미는 흑미와 적미에 비해 유의하게 항산화 활성이 낮게 나타났다. 본 연구에서 분석한 총폴리페놀, 총플라보노이드, 안토시아닌과 ABTS DPPH 라디칼 소거능에서 측정한 $IC_{50}$ 값과는 높은 부의 상관관계를 보이므로 항산화 성분과 항산화 활성은 상관관계가 높았다.

• Journal of Microbiology and Biotechnology
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• 제20권5호
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• pp.893-903
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• 2010

A cellulolytic and xylanolytic enzyme complex-producing alkalothermoanaerobacterium strain, Tepidimicrobium xylanilyticum BT14, is described. The cell was Grampositive, rod-shaped, and endospore-forming. Based on 16S rRNA gene analysis and various lines of biochemical and physiological properties, the strain BT14 is a new member of the genus Tepidimicrobium. The strain BT14 cells had the ability to bind to Avicel, xylan, and corn hull. The pH and temperature optima for growth were 9.0 and $60^{\circ}C$, respectively. The strain BT14 was able to use a variety of carbon sources. When the bacterium was grown on corn hulls under an anaerobic condition, a cellulolytic and xylanolytic enzyme complex was produced. Crude enzyme containing cellulase and xylanase of the strain BT14 was active in broad ranges of pH and temperature. The optimum conditions for cellulase and xylanase activities were pH 8.0 and 9.0 at $60^{\circ}C$, respectively. The crude enzyme had the ability to bind to Avicel and xylan. The analysis of native-PAGE and native-zymograms indicated the cellulosebinding protein showing both cellulase and xylanase activities, whereas SDS-PAGE zymograms showed 4 bands of cellulases and 5 bands of xylanases. Evidence of a cohesinlike amino acid sequence seemed to indicate that the protein complex shared a direct relationship with the cellulosome of Clostridium thermocellum. The crude enzyme from the strain BT14 showed effective degradation of plant biomass. When grown on corn hulls at pH 9.0 and $60^{\circ}C$ under anaerobic conditions, the strain BT14 produced ethanol and acetate as the main fermentation products.

• Journal of Microbiology and Biotechnology
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• 제21권3호
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• pp.284-292
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• 2011

An endocellulase-free multienzyme complex was produced by a thermophilic anaerobic bacterium, Thermoanaerobacterium thermosaccharolyticum strain NOI-1, when grown on xylan. The temperature and pH optima for growth were $60^{\circ}C$ and 6.0, respectively. The bacterial cells were found to adhere to insoluble xylan and Avicel. A scanning electron microscopy analysis showed the adhesion of xylan to the cells. An endocellulase-free multienzyme complex was isolated from the crude enzyme of strain NOI-1 by affinity purification on cellulose and Sephacryl S-300 gel filtration. The molecular mass of the multienzyme complex was estimated to be about 1,200 kDa. The multienzyme complex showed one protein on native PAGE, one xylanase on a native zymogram, 21 proteins on SDS-PAGE, and 5 xylanases on a SDS zymogram. The multienzyme complex consisted of xylanase, ${\beta}$-xylosidase, ${\alpha}$-L-arabinofuranosidase, ${\beta}$-glucosidase, and cellobiohydrolase. The multienzyme complex was effective in hydrolyzing xylan and corn hulls. This is the first report of an endocellulase-free multienzyme complex produced by a thermophilic anaerobic bacterium, T. thermosaccharolyticum strain NOI-1.

• Journal of Microbiology and Biotechnology
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• 제17권9호
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• pp.1568-1572
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• 2007

To develop a natural fungicide against Botrytis cinerea and Colletotrichum gloeosporioides, a total of 25 essential oils were tested for their fumigant activity against post-harvest pathogens. The vaporous phases of oils were treated to each fungus on potato dextrose agar medium in half-plate separated Petri plates at $10\;{\mu}g$ per plate. The essential oil of Illicium verum strongly inhibited the mycelial growth of both B. cinerea and C. gloeosporioides by over 90%. On the other hand, the essential oil of Schizonepeta tenuifolia showed inhibitory activity against mycelial growth of only B. cinerea by over 90%. Gas chromatography-mass spectrometry and bioassay indicated trans-anethole in I. verum and menthone in S. tenuifolia as a major antifungal constituent. The essential oils of I. verum and S. tenuifolia and their major constituents could be used to manage post-harvest diseases caused by B. cinerea and C. gloeosporioides.

• Fisheries and Aquatic Sciences
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• 제26권2호
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• pp.105-116
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• 2023

Improved fish post-harvest technologies (IFPT) have been promoted as more efficient methods of fish processing, preservation, and value addition than the traditional methods prevalent in developing countries. The adoption rates, however, do not appear to be convincing. The purpose of this study was to determine the socio-demographic and psychological factors that influence intention of Kenyan farmed fish traders to use IFPT. The technology acceptance model (TAM) was used to properly explain the impact of TAM constructs such as perceived usefulness (PU), perceived ease of use (PEOU), and attitude (ATT), as well as socio-demographic factors such as gender, age, education level and fish trading experience on traders' intention to use the technologies. A cross-sectional survey was conducted to collect data using a semi-structured questionnaire from 146 traders in Busia, Siaya and Kakamega counties. At a significance level of p = 0.05, a linear regression model was used to examine the socio-demographic and psychological determinants of the traders' behavioral intention to use the improved technologies. The regression analysis revealed that PU (β = 0.443; p = 0.000), PEOU (β = 0.364; p = 0.000) and ATT (β = 0.615; p = 0.000) influence traders' intention to use IFPT, with ATT having the highest influence on intention. However, the traders' socio-demographic characteristics have no effect on their intention to use the technologies, as the coefficients for gender (β = 0.148; p = 0.096), age (β = 0.016; p = 0.882), level of education (β = -0.135; p = 0.141) and fish trading experience (β = 0.017; p = 0.869) are all insignificant. These findings show that the traders intend to use IFPT and will use them when it is in their best economic interests.

• 한국식품위생안전성학회지
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• 제30권3호
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• pp.249-257
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• 2015

위생적인 수확후처리를 통하여 안전한 농산물 생산을 유도하기 위하여 영양부추를 대상으로 수확후 처리시설 모델을 개발하였으며 개발된 수확후 처리시설 설치와 위생교육이 미생물 안전에 미치는 효과를 검증하고자 본 연구를 수행하였다. 이를 위하여 양주지역 영양부추 생산 농가의 수확 후 처리시설 환경과 영양부추에서 위생지표세균(일반세균수, 대장균군, E. coli)과 병원성미생물(Escherichia coli O157:H7, Salmonella spp., Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus)을 조사하였다. 그 결과, 빗, 칼, 도마 등 수확후 처리시설에서 사용하는 작업도구의 일반세균수 오염수준은 수확후 처리시설 설치농가(A, B)에서 수확후 처리시설 비설치농가(C) 보다 1.44~2.33 log CFU / 100$100cm^2$ 정도 낮았다. 특히 도마의 경우 A농가에서 1.00 log CFU / 100$100cm^2$이하, B 농가에서 2.23 log CFU / $100cm^2$인데 반해 C 농가에서는 6.03 log CFU / $100cm^2$로 농가간의 위생 상태에 따라 B. cereus의 오염수준이 차이가 크게 나타났다. 또한 지하수에 침지 한 영양부추에서 침지 전 보다 대장균군이 0.57~1.89 log CFU/g이 증가하였다. E. coli는 영양부추, 침지한 후 지하수, 토양에서 검출되었으며, E. coli O157:H7, Salmonella spp., L. monocytogenes는 검출되지 않았다. 따라서 본 연구의 결과를 통하여 소규모 수확 후 처리시설 설치와 위생교육을 통하여 농가 내 수확후처리 환경의 위생을 개선하는데 효과적이라 판단된다. 이와 더불어 유해미생물에 의한 식중독사고를 사전에 예방하기 위해서는 수확 후에 오염된 유해미생물을 저감화 할 수 있는 세척, 소독 기술의 개발과 도입이 필요할 것으로 사료된다.

• 한국산림과학회지
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• 제102권1호
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• pp.82-89
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• 2013

벌채 수확은 토양 내 탄소 동태를 변화시킬 수 있는 중요한 교란 중 하나이다. 그러나 수확에 따른 토양탄소 변화를 현지에서 장기간 연구하는 데에는 여러 가지 제한 요건이 있기 때문에 수학적 모델을 이용하여 장기적인 토양탄소 변화 경향을 효율적으로 추정할 수 있다. 본 연구에서는 최근 개발된 한국형 산림토양탄소 모델(KFSC 모델)을 이용하여 국내 중부지방 소나무(Pinus densiflora S. et Z.) 임분을 대상으로 수확의 주기, 강도, 수확 후 잔재물 처리방법에 따른 산림토양탄소 동태의 장기 변화를 모의하였다. 모의 시나리오는 3개의 수확 주기(50년, 80년, 100년), 2개의 수확 강도(재적 대비 30%의 부분수확 및 100%의 개벌수확), 2개의 수확 후 잔재물 처리방법(지상부 잔재물의 전량 수거 및 전량 방치) 등을 조합하여 총 12개로 이루어졌으며, 연간 토양탄소 저장량의 변화를 400년 간 모의하였다. 모의 결과, 400년 후 30 cm 깊이까지의 토양탄소 저장량은 시나리오별로 50.3-55.8 Mg C $ha^{-1}$(현재 토양탄소 저장량 대비: 98.1-108.9%)의 범위를 나타냈다. 수확 후 잔재물을 전량 방치할 경우 잔재물을 전량 수거할 때보다 토양탄소 저장량이 2.5-11.0% 증가하는 것으로 모의되었으나, 수확 주기 및 강도에 따른 토양탄소 저장량 변화에서는 일정한 경향이 나타나지 않았다. 토양탄소 저장량의 변화 경향은 고사유기물의 변화 경향과 일치하였으며, 고사유기물의 변화 경향은 수확 시 발생하는 고사유기물의 양과 수확 후 임분 생장 형태에 의해 달라지는 것으로 나타났다.

• Agricultural and Biosystems Engineering
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• 제3권1호
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• pp.10-17
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• 2002

Quality attributes of apple are greatly affected by the cooling rate and environmental conditions during storage. Studies were conducted to evaluate the effect of cooling rate on different quality attributes of apple. The effect of $O_2$ pulldown rate of the CA chamber on the quality of apple was also determined. Two methods were used viz. conventional CA procedure and rapid CA procedure. Apples stored by medium and slow cooling methods lost its flesh firmness significantly from an initial level of 4.55 kg to 2.83 kg and 2.27 kg, respectively on 35 days after storage whereas, in rapid cooling, the firmness level changed from 4.55 kg to 3.20 kg on 35 days after storage. At the end of 35 days of storage, titratable acidity decreased insignificantly from an initial value of 0.24l% to 0.239% in the case of rapid CA whereas in the case of conventional CA it dropped significantly to 0.215% from its initial level. The initial flesh firmness of 4.55 kg also changed significantly to 4.05 kg on 35 days after storage in conventional CA whereas in rapid CA it changed to 4.36 kg, which was found to be non-significant at 5% level of significance. Total soluble solids increased from an initial level of $12.43^{\circ}$Bx to $12.60^{\circ}C.$ Bx on 35 days after storage in rapid CA whereas it increased to $13.07^{\circ}$ Bx in conventional CA. Ascorbic acid content of apple juice decreased insignificantly from 6.67 mg/100 mL to 5.87 mg/100 mL on 35 days after storage in rapid CA whereas in conventional CA, it decreased significantly to 5.27 mg/100 mL from its initial level.

• 한국식품저장유통학회지
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• 제30권2호
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• pp.205-223
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• 2023

Fresh mushrooms are vulnerable to browning and tissue changes after harvest. This study monitored the external appearance, physicochemical quality indicators, and nutritional and functional components of a white beech mushroom (Hypsizygus marmoreus) variety (EG2020) newly developed in Korea during cold storage for up to 42 days. Two existing varieties of white H. marmoreus, namely H6 from Korea and HKT from Japan, were used for comparison. The mechanical texture of EG2020 was superior to H6 and HKT due to the increasing hardness of the pileus with time. Browning, in terms of the total color difference during storage, was found to be the most severe in HKT. In terms of composition, EG2020 had the highest total free sugar content, a large amount of organic acids, and higher sugar content than H6 and HKT. EG2020 also contained the largest amount of 𝛽-glucan, and its amount increased during storage. In sensory evaluation, EG2020 received higher scores than HKT in flavor, taste, appearance, and texture. Therefore, the EG2020 variety is more stable than HKT during storage and distribution.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2007년도 춘계학술발표회
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• pp.76.1-76.1
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• 2007