• Journal of Microbiology and Biotechnology
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• 제17권9호
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• pp.1430-1436
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• 2007

[ ${\alpha}$ ]-Galactosidase was immobilized in a mixture of k-carrageenan and locust bean gum. The properties of the free and immobilized enzyme were then determined. The optimum pH for both the soluble and immobilized enzyme was 4.8. The optimum temperature for the soluble enzymes was $50^{\circ}C$, whereas that for the immobilized enzyme was $55^{\circ}C$. The immobilized enzyme was used in batch, repeated batch, and continuous modes to degrade the raffinose-family sugars present in soymilk. Two hours of incubation with the free and immobilized ${\alpha}$-galactosidases resulted in an 80% and 68% reduction in the raffinose oligo saccharides in the soymilk, respectively. In the repeated batch, a 73% reduction was obtained in the fourth cycle. A fluidized bed reactor was also designed to treat soymilk continuously and the performance of the immobilized ${\alpha}$-galactosidase tested at different flow rates, resulting in a 90% reduction of raffinose-family oligosaccharides in the soymilk at a flow rate 40 ml/h. Therefore, the present study demonstrated that immobilized ${\alpha}$-galactosidase in a continuous mode is efficient for reducing the oligosaccharides present in soymilk, which may be of considerable interest for industrial application.

• 원예과학기술지
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• 제35권2호
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• pp.243-251
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• 2017

Plants have evolved to adapt to abiotic stresses, such as salt, cold, and drought stress. In this study, we conducted an in-depth analysis of drought resistance mechanisms by constructing a gene co-expression network in Chinese cabbage (Brassica rapa ssp. pekinensis L.). This drought stress co-expression network has 1,560 nodes, 4,731 edges, and 79 connected components. Based on genes that showed significant co-expression in the network, drought tolerance was associated with the induction of reactive oxygen species removal by raffinose family oligosaccharides and inositol metabolism. This network could be a useful tool for predicting the functions of genes involved in drought stress resistance in Chinese cabbage.

• 한국작물학회지
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• 제59권3호
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• pp.319-324
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• 2014

콩 성숙 종자에 존재하는 raffinose 및 stachyose의 함량이 적은 콩 품종 육성을 위하여 요구되는 기본정보를 얻기 위하여 장려품종, 육성계통, 유전자원등 22개의 유전자원과 2년간 함량변이를 관찰한 결과는 아래와 같았다. 1. Raffinose의 함량(g/kg)은 1년차의 경우 $2.68{\pm}0.21-5.87{\pm}2.43$의 범위를 보였고 2년차에서는 $3.24{\pm}0.37-9.05{\pm}0.16$의 범위를 보였다. 2. Stachyose의 함량(g/kg)은 1년차에서 $4.23{\pm}0.98-27.68{\pm}9.90$, 2년차에서는 $5.11{\pm}1.09-25.32{\pm}0.35$의 범위를 보였다. 3. 분산분석 결과 유전자형과 년차간 stachyose 및 raffinose의 함량은 고도의 유의성을 보였고 상호작용은 인정되지 않았다. 4. Stachyose 함량에서는 2년차 평가 모두에서 Da-7, 116-13, RS-78 유전자형이 유의하게 낮은 함량을 보였다. 5. Raffinose 함량은 1년차 평가에서 Hwangkumkong 및 P34-162 유전자형이 낮은 값을 보였고, 2년차에서는 116-13과 Da-7 유전자형이 낮은 값을 보였다. 6. Raffinose와 stachyose의 함량간에는 2년차 평가에서 유의한 정의 상관관계($R^2=0.1985^*$)을 보였다.

• 한국작물학회지
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• 제62권2호
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• pp.143-148
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• 2017

콩의 성숙 종실에 들어 있는 stachyose 및 raffinose 성분은 난소화성당으로 콩이나 콩 제품의 품질, 영양가치 및 가공적성을 저하시키는 것으로 알려져 있다. Stachyose 및 raffinose의 함량이 낮은 육종계통들의 농업적 형질을 평가하여 용도별 난소화성당의 함량이 낮은 콩 품종 육성을 위한 자료를 얻기 위하여 본 실험이 진행되었으며 얻어진 결과를 요약하면 다음과 같다. 1. 전체 7개의 모본을 이용하여 난소화성당의 함량이 낮은 10개의 $F_6$ 선발 계통은 포장 평가에서 초장, 종피색, 백립중, 성숙기, 수량, 도복등 농업형질에서 다양한 차이를 보였다. 2. 883-1 선발 계통은 백립중이 14.3 g으로 수확기가 9월 21일로 조숙이며 도복이 강하여 난소화성당 저함량 조생 소립품종 육성을 위한 중간모본으로 적당하였다. 3. 백립중이 20-26 g 범위의 중립인 5개의 계통(15A1, 15D1, RS-5, RS-64, RS-70)중에서 RS-5 계통은 백립중이 20.1 g 정도이며 종자상태가 매우 우수하고 도복에 강하여 난소화성당의 함량이 낮은 중립콩 품종 육성을 위한 중간모본으로 이용성이 높았다. 4. 난소화성당의 함량이 낮아 품질 및 기능성이 우수한 장류용콩 품종 육성을 위한 중간 모본으로 14G20 선발계통은 도복이 강하며 수량성이 매우 높고 백립중이 29.7 g 정도의 대립이었다. 5. 검정종피와 녹색자엽을 가진 RS-21 계통은 도복이 강하며, 수량성이 매우 높고 백립중이 28.7 g 정도의 대립으로, 난소화성당의 함량이 낮은 특수용콩 품종 육성을 위한 중간모본으로 이용성이 높았다.

• Journal of Applied Biological Chemistry
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• 제54권4호
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• pp.244-251
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• 2011

Galactinol and rafinose accumulation in plants is associated with stressful environmental conditions such as cold, heat, or dehydration by the action of galactinols synthase (GolS) in the raffinose family of oligosaccharides biosynthetic pathway from UDP-galactose. Moreover, several reports mentioned that GolS transcription is up regulated by various environmental stresses like cold, heat, dehydration. Therefore, to determine whether MoGolS1 was induced with the abiotic stress we analyzed the expression pattern of the gene under various abiotic stresses like heat, cold, abscisic acid, sucrose and salt concentration in the lemon balm plants grown in standard MS medium. The MoGolS1 gene was 981-bp in length encoding 326 amino acids in its sequence and shared 77 and 76% sequence similarity with Arabidopsis thaliana galactinol synthase4 (AtGolS4) and AtGolS1 genes respectively. The MoGolS1 gene was strongly expressed by the abiotic stress induced by sucrose, ABA or heat shock. It was also expressed in responses to cold, Identification and Functional Characterization of the GALACTINOL SYNTHASgene induction with various stresses may be possible for itscrucial function in abiotic stress tolerance in plants, providing a good engineering target for genetic engineering.

• Journal of Microbiology and Biotechnology
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• 제20권11호
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• pp.1546-1554
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• 2010

A bacterial strain capable of producing extracellular ${\alpha}$-galactosidase was isolated from a sample of sugarcane industrial waste. Microbiological, physiological, and biochemical studies revealed that the isolate belonged to Bacillus sp. Furthermore, based on a 16S rDNA sequence analysis, the new isolate was identified as Bacillus megaterium VHM1. The production of ${\alpha}$-galactosidase was optimized based on various physical culture conditions. Guar gum and yeast extract acted as the best carbon and nitrogen sources, respectively. The optimum pH was 7.5 and the enzyme remained stable over a pH range of 5-9. The enzyme was optimally active at $55^{\circ}C$ and thermostable with a half-life of 120 min, yet lost 90% of its residual activity within 120 min at $60^{\circ}C$. One mM concentrations of $Ag^2$, $Cu^2$, and $Hg^{2+}$ strongly inhibited the ${\alpha}$-galactosidase, whereas the metal ions $Fe^2$, $Mn^{2+}$, and $Mg^{2+}$ had no effect on the ${\alpha}$-galactosidase activity, and $Zn^{2+}$, $Ni^{2+}$, and $Ca^{2+}$ reduced the enzyme activity slightly. When treated with the B. megaterium VHM1 enzyme, the flatulence-causing sugars in soymilk were completely hydrolyzed within 1.5 h.

• 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.