• Food Science and Biotechnology
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• 제16권1호
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• pp.99-103
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• 2007

The purpose of this study was to develop a simple detection method, possibly at the species-level, that allows for large-scale screening of bifidobacteria. Human fecal samples were plated on MRS-raffinose agar containing cysteine and neomycin sulfate, serving as selective pressure for bifidobacteria, and 0.003%(w/v) bromocresol green. All of the test strains grew well on this medium at $37{\pm}1^{\circ}C$, forming white colonies surrounded by yellow halos, which presented a sharp contrast against the green background. In this disc assay, the required incubation time to develop a yellowish zone varied with the species of Bifidobacterium that was tested, allowing for differential counts and easy identification at the species-level: 10-14 hr for B. bifidum, 20-22 hr for B. catenulatum and B. infantis. and 24-25 hr for B. longum and B. breve. No apparent color was observed for B. angulatum and B. adolescentis 28 hr after inoculation. To evaluate the results of pH indicator-based identification, individual isolates were subjected to a colony-PCR experiment with genus-specific primers. The amplified products from the isolates were in good accordance with those from the reference strains at a level of 95% agreement. These results suggest that the present method could be conveniently applied to cell counts, as well as to the preliminary identification of bifidobacteria from a variety of sample types including human feces, dairy products, and commercial probiotic supplements.

• Molecules and Cells
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• 제39권6호
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• pp.477-483
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• 2016

Heat shock factors (Hsfs) are central regulators of abiotic stress responses, especially heat stress responses, in plants. In the current study, we characterized the activity of the Hsf gene HsfA3 in Arabidopsis under oxidative stress conditions. HsfA3 transcription in seedlings was induced by reactive oxygen species (ROS), exogenous hydrogen peroxide ($H_2O_2$), and an endogenous $H_2O_2$ propagator, 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB). HsfA3-overexpressing transgenic plants exhibited increased oxidative stress tolerance compared to untransformed wild-type plants (WT), as revealed by changes in fresh weight, chlorophyll fluorescence, and ion leakage under light conditions. The expression of several genes encoding galactinol synthase (GolS), a key enzyme in the biosynthesis of raffinose family oligosaccharides (RFOs), which function as antioxidants in plant cells, was induced in HsfA3 overexpressors. In addition, galactinol levels were higher in HsfA3 overexpressors than in WT under unstressed conditions. In transient transactivation assays using Arabidopsis leaf protoplasts, HsfA3 activated the transcription of a reporter gene driven by the GolS1 or GolS2 promoter. Electrophoretic mobility shift assays showed that GolS1 and GolS2 are directly regulated by HsfA3. Taken together, these findings provide evidence that GolS1 and GolS2 are directly regulated by HsfA3 and that GolS enzymes play an important role in improving oxidative stress tolerance by increasing galactinol biosynthesis in Arabidopsis.

• Applied Biological Chemistry
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• 제49권3호
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• pp.180-185
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• 2006

본 연구는 Debaryomyces sp.가 생산하는 ${\alpha}-galactosidase$의 mannobiose-sepharose 담체합성법에 의한 affinity column chromatography를 수행하여 효소정제, 효소 화학적 성질 및 galactosyl mannooligosacchrides에 대한 기질특이성 규명을 주요 목적으로 하였다. 배양시간별 활성과 pH의 변화에서 배양시간 40시간부터 활성이 증가하고 있으며, 70시간에서 25.8unit/ml의 최대활성을 나타내고 있으며, 배양초기 pH 6.0에서 시작되어 배양말기에는 pH 8을 나타내는 pH의 변화를 보였다. 최적 pH는 4.0, 최적온도는 $60^{\circ}C$이며 $pH\;3{\sim}4.5$에서 100%의 잔존활성을 나타낸 반면 pH 8.0에서는 20%로 급격히 감소하였고. 온도안정성에서 $30{\sim}50^{\circ}C$에서는 100%의 잔존활성을 나타내었으나 $70^{\circ}C$ 이상에서는 20% 이하의 잔존활성을 나타내었다. $Hg^{2+}$에 의해서 54%, $Ag^{2+}$에 의해서는 85%로 저해되었으며, 그 이외의 이온에 대해서는 큰 영향을 받지 않았다. Debaryomyces sp.유래 ${\alpha}-galactosidase$는 24시간 반응 후 melibiose, $Gal^3Man_3$를 완전 가수분해 하여 각각 galactose와 glucose, galactose와 mannotriose로 분해되었으나 $Gal^3Man_4$에 대해서는 12시간 반응시켜도 기질로부터 galactose 유리가 불가능함이 확인되었다.

• 한국약용작물학회지
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• 제26권6호
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• pp.482-489
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• 2018

Background: This study was carried out to determine the physicochemical components of Rehmannia glutinosa (RG) fermented with Rhizopus delemar. Methods and Results: Physicochemical components such as changes in moisture content, pH value, total acidity, amount of reducing sugars as well as quantity of free sugars, free amino acids, and catalpol were investigated. Result showed that, the moisture content ranged from 64.26 to 65.51%. The pH and total acidity of the fermented RG decreased significantly during fermentation. The reducing sugar content ranged from 0.10 to 1.34%. The most abundant main free sugars were identified as raffinose, xylose, glucose, fructose, and sucrose. The sucrose content in 80% ethanol and in water extracts increased during RG fermentation. In total, 26 free amino acids were detected, including seven essential amino acids. In addition, the quantity of free amino acids decreased significantly during fermentation. Finally, the catalpol content of the fermented RG was highest on the $2^{nd}$ day of fermentation at 2,028.67 mg/ 100 g. Conclusions: These results indicated that fermentation of Rhizopus delemar could be used to enhance biological activity, and that fermented RG could be used as a functional material and as an edible resource in food and functional materials industries.

• Journal of Applied Biological Chemistry
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• 제64권2호
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• pp.141-151
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• 2021

Insects affect crop harvest yield and quality, making plant response mechanisms to insect herbivores a heavily studied topic. However, analysis of plant responses to honeybees is rare. In this study, comprehensive metabolic profiling of Arabidopsis thaliana exposed to honeybees was performed to investigate which metabolites were changed by the insect. A total of 85 metabolites-including chlorophylls, carotenoids, glucosinolates, policosanols, tocopherols, phytosterols, β-amyrin, amino acids, organic acids, sugars, and starch-were identified using high performance liquid chromatography, gas chromatography-mass spectrometry, and gas chromatography-time-of-flight mass spectrometry. The metabolite profiling analysis of Arabidopsis exposed to honeybees showed higher levels of stress-related metabolites. The levels of glucosinolates (glucoraphanin, 4-methoxyglucobrassicin), policosanols (eicosanol, docosanol, tricosanol, tetracosanol), tocopherols (β-tocopherol, γ-tocopherol), putrescine, lysine, and sugars (arabinose, fructose, glucose, mannitol, mannose, raffinose) in Arabidopsis exposed to honeybees were higher than those in unexposed Arabidopsis. Glucosinolates act as defensive compounds against herbivores; policosanols are components of plant waxes; tocopherols act as an antioxidant; and putrescine, lysine, and sugars contribute to stress regulation. Our results suggest that Arabidopsis perceives honeybees as a stress and changes its metabolites to overcome the stress. This is the first step to determining how Arabidopsis reacts to exposure to honeybees.

• Journal of Microbiology and Biotechnology
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• 제32권6호
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• pp.749-760
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• 2022

α-Galactosidase is a debranching enzyme widely used in the food, feed, paper, and pharmaceuticals industries and plays an important role in hemicellulose degradation. Here, T26, an aerobic bacterial strain with thermostable α-galactosidase activity, was isolated from laboratory-preserved lignocellulolytic microbial consortium TMC7, and identified as Parageobacillus thermoglucosidasius. The α-galactosidase, called T26GAL and derived from the T26 culture supernatant, exhibited a maximum enzyme activity of 0.4976 IU/ml when cultured at 60℃ and 180 rpm for 2 days. Bioinformatics analysis revealed that the α-galactosidase T26GAL belongs to the GH36 family. Subsequently, the pET-26 vector was used for the heterologous expression of the T26 α-galactosidase gene in Escherichia coli BL21 (DE3). The optimum pH for α-galactosidase T26GAL was determined to be 8.0, while the optimum temperature was 60℃. In addition, T26GAL demonstrated a remarkable thermostability with more than 93% enzyme activity, even at a high temperature of 90℃. Furthermore, Ca²⁺ and Mg²⁺ promoted the activity of T26GAL while Zn²⁺ and Cu²⁺ inhibited it. The substrate specificity studies revealed that T26GAL efficiently degraded raffinose, stachyose, and guar gum, but not locust bean gum. This study thus facilitated the discovery of an effective heat-resistant α-galactosidase with potent industrial application. Meanwhile, as part of our research on lignocellulose degradation by a microbial consortium, the present work provides an important basis for encouraging further investigation into this enzyme complex.

• 대한본초학회지
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• 제36권6호
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• pp.47-61
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• 2021

Objectives : 'Steaming and drying' is a traditional processing method that has been used to produce Suk-ji-hwang (熟地黃; Rehmanniae Radix Preparata) from Ji-hwang (地黃, the fresh root of Rehmannia glutinosa Liboschitz ex Steudel; Rehmanniae Radix). The steaming and drying process, which is proceeded in heating and moisturizing conditions, plays a crucial role in the change of therapeutic effect of Ji-hwang, presumably due to the modification of its chemical constituents. In this article, the chemical influence of the 'Steaming and drying' process was investigated for understanding the underlying mechanism of chemical modification of Ji-hwang. Methods : The articles regarding the modifications of chemical constituents of Ji-hwang during the 'Steaming and drying' process were collected and analyzed to investigate the influence of the processing to Ji-hwang. Results : The results indicated that iridoid glycosides were degraded to their aglycones and sugars, and such degradations occurred faster at a high pressure than at an atmospheric pressure during the process. The contents of catalpol, ajugol, and acteoside were decreased, while those of rehmannioside A and D were slightly increased during the repeated processing. The contents of oligosaccharides, namely sucrose, maltose, raffinose, and stachyose (except for manninotriose), were decreased, while those of monosaccharides, glucose and fructose, were increased by the repeated processing. Conclusions : These results demonstrate that the 'Steaming and drying' process influenced the chemical constituents of Ji-hwang and provide probable basis for the therapeutic modification of Suk-ji-hwang after the processing of Ji-hwang.

• Animal Bioscience
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• 제36권10호
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• pp.1568-1577
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• 2023

Objective: A study was conducted to determine the chemical composition of banana meal and rice bran from Australia or South-East Asia and test the hypothesis that there are no differences in rice bran produced in different countries, but there are differences between full-fat and defatted rice bran. Methods: Two sources of banana meal and 22 sources of rice bran (full-fat or defatted) from Australia or South-East Asia were used. All samples were analyzed for dry matter, gross energy, nitrogen, amino acids (AA), acid hydrolyzed ether extract (AEE), ash, minerals, total starch, insoluble dietary fiber, and soluble dietary fiber. Banana meal was also analyzed for sugars including glucose, fructose, maltose, sucrose, stachyose, and raffinose. Results: Chemical analysis demonstrated that banana meal from the Philippines is primarily composed of starch. Full-fat rice bran from Australia had greater (p<0.05) concentrations of AEE, lysine, and glycine than samples from the Philippines and Vietnam. Full-fat rice bran from Australia and Thailand had greater (p<0.05) concentrations of gross energy and most AA than rice bran from Vietnam. Full-fat rice bran from Australia had greater (p<0.05) concentrations of tryptophan and manganese than all other sources, but full-fat rice bran from the Philippines contained less (p<0.05) zinc than all other sources of rice bran. Gross energy, AEE, and copper were greater (p<0.05) in full-fat rice bran compared with defatted rice bran, but defatted rice bran contained more (p<0.05) crude protein, ash, insoluble dietary fiber, total dietary fiber, AA, and some minerals than full-fat rice bran. Conclusion: Banana meal is a high-energy source that can be used as an alternative ingredient in livestock diets. Full-fat rice bran from Australia and Thailand contained more concentrations of AEE and AA than samples from the Philippines or Vietnam. Full-fat rice bran had more gross energy and AEE than defatted rice bran, whereas defatted rice bran contained more crude protein, ash, and total dietary fiber.

• 한국환경농학회지
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• 제29권2호
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• pp.120-128
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• 2010

국내 육성 검정콩 품종을 대상으로 기존 단순 재배지역 차이의 관점이 아니라, 작물의 생육환경에 영향을 줄 수 있는 위도 차이의 관점에서, 검정콩 종실 함유 조단백질, 조지방, 지방산 및 유리당의 함량변이를 검토한 결과, 검정콩 품종별 조단백질 함량은 검정콩 3호가 43.9%, 조지방 함량은 검정콩 4호가 21.8%로 품종 내에서 가장 높은 양상을 나타내었다. 그러나 공시된 검정콩 품종 중 검정콩 4호를 제외한 대부분의 품종에서는 재배지의 위도차에 따른 조단백질 및 조지방의 함량 차이는 없었다. 재배지의 위도 차이에 따른 지방산 조성의 변이는 고위도인 수원지역에서 재배한 검정콩 품종 대부분이 저위도인 밀양에서 재배한 품종보다 oleic acid 함량은 높았고, linoleic acid 및 linolenic acid 함량은 낮았다. 한편, 유리당 중에서 sucrose 함량은 검정콩 3호가, raffinose 함량은 검정콩 3호, 검정콩 4호, 일품검정콩 및 청자콩이, stachyose 함량은 검정콩 1호가 저위도에서 고위도 보다 높은 양상을 나타내었다. 따라서 위도에 따른 재배지역과 품종 간 조단백질, 조지방 및 지방산 함량 사이에는 상호작용이 없는 것으로 나타나, 이들 성분의 함량은 환경적 요인보다는 유전적 요인에 의한 것으로 판단된다. 그러나 당 함량에서는 glucose, sucrose, stachyose는 서로 상호작용이 있어 품종에 따라 위도별 재배환경이 유전적 요인보다도 크게 작용하는 것으로 판단된다.

• 한국식품영양과학회지
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• 제42권8호
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• pp.1255-1262
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• 2013

본 연구는 검정콩 2호, 대원콩, 선흑콩, 소명콩, 신팔달콩 2호, 진품콩 2호, 태광콩, 푸른콩에 대해 이화학적 특성과 기능성 성분에 대한 기초 자료를 얻기 위하여 실시하였다. 일반성분 분석 결과, 수분함량은 5.50~6.16% 범위였고, 조단백 함량은 40% 내외로 시료 간 큰 차이는 없었다. 조지방 함량은 푸른콩, 대원콩, 소명콩 및 검정콩 2호가 20% 내외로 비교적 높은 편이었고, 진품, 선흑, 신팔달콩 2호, 태광콩는 15% 내외로 비교적 낮은 편이었다. 회분 함량은 4.89~5.86%로 나타내어 품종 간의 큰 차이를 보이지 않고, 탄수화물 함량은 26.20~35.45%로 분포하였다. 무기질의 함량에서 콩나물용 칼슘 함량은 소명콩이 406.36 mg/100 g으로 가장 높았고, 마그네슘 함량은 신팔달 2호가 247.79 mg/100 g으로 가장 높았다. 이에 반해 진품콩은 칼슘이 199.51 mg/100 g으로 가장 낮았고, 선흑콩은 가장 낮은 마그네슘 함량(90.03 mg/100 g)을 나타냈다. 총 이소플라본 함량은 97.54~402.00 mg/100 g으로 품종 간 차이를 보였다. 시료 중 가장 높은 함량을 나타낸 것은 콩나물용 소명콩이었고, 가장 낮은 함량을 나타낸 것은 밥밑용 선흑콩이었다. 총 올리고당 함량은 5.84~9.35 mg/100 g이었다. 총 올리고당 중 sucrose의 함량이 약 50% 정도로 나타났다. Raffinose는 0.52~0.81 mg/100 g으로 함량이 나타났고, stachyose의 함량은 2.05~3.45 mg/100 g으로 나타났다. Bracassisterol, campesterol, stigmasterol, ${\beta}$-sitosterol을 분석한 것으로 ${\beta}$-sitosterol이 평균적으로 식물성 sterol의 50%를 차지하였고, 그 다음으로 campesterol, stigmasterol 순서였으며 bracassisterol은 소량이 분석되었다. Phytic acid 함량은 신팔달콩 2호와 진품콩 2호가 0.86%, 1.65%로 이를 제외한 시료들은 약 2% 정도를 함유한 것으로 분석되었다. 식이섬유소 함량은 24.20~29.20% 범위로 나타났다.