• 식물조직배양학회지
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• 제27권5호
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• pp.387-393
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• 2000

The process by which Agrobacterium tumefaciens genetically transforms plants involves a complex series of reactions communicated between the pathogen and the plants. To identify plant factors involved in agrobacterium-mediated plant transformation, a large number of T-DNA inserted Arabidopsis thaliana mutant lines were investigated for susceptibility to Agrobacterium infection by using an in vitro root inoculation assay. Based on the phenotype of tumorigenesis, twelve T-DNA inserted Arabidopsis mutants(rat) that were resistant to Agrobacterium transformation were found. Three mutants, rat1, rat3, and rat4 were characterized in detail. They showed low transient GUS activity and very low stable transformation efficiency compared to the wild-type plant. The resistance phenotype of rat1 and rats resulted from decreased attachment of Agrobacterium tumefaciens to inoculated root explants. They may be deficient in plant actors that are necessary for bacterial attachment to plant cells. The disrupted genes in rat1, rat3, and rat4 mutants were coding a arabinogalactan protein, a likely cell wall protein and a cellulose synthase-like protein, respectively.

• Preventive Nutrition and Food Science
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• 제22권2호
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• pp.100-106
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• 2017

To elucidate new biological ingredients in cold-brew coffee extracted with cold water, crude polysaccharide (CCP-0) was isolated by ethanol precipitation, and its immune-stimulating activities were assayed. CCP-0 mainly comprised galactose (53.6%), mannose (15.7%), arabinose (11.9%), and uronic acid (12.4%), suggesting that it might exist as a mixture of galactomannan and arabinogalactan. CCP-0 significantly increased cell proliferation on both murine peritoneal macrophages and splenocytes in a dose dependent manner. CCP-0 also significantly augmented nitric oxide and reactive oxygen species production by murine peritoneal macrophages. In addition, macrophages stimulated by CCP-0 enhanced production of various cytokines such as tumor necrosis factor-${\alpha}$, interleukin (IL)-6, and IL-12. In an in vitro assay for intestinal immune-modulating activity, CCP-0 showed higher bone-marrow cell-proliferation activity through Peyer's patch cells at $100{\mu}g/mL$ than the negative control. These results suggest that CCP-0 may potentially enhance macrophage functions and the intestinal immune system.

• Journal of the Korean Wood Science and Technology
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• 제26권3호
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• pp.26-32
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• 1998

The chemical composition of differentiating xylem of Populus deltoides M. were investigated and compared with those from sapwood. The cell wall polysaccharides were extracted sequentially from a differentiating xylem and sugar composition was analyzed with G.L.C, H.P.L.C and gel chromatograpy. The pectin substance and hemicellulose are rich in the cell wall of differentiating xylem. The $H_2O$ extract polysaccharides from differentiating xylem were composed with xylose-glucose residues which seem to be xyloglucan and a pectin. The arabinogalactan and the mannan were extracted with $Na_2CO_3$ solution and also the xylan was extracted with KOH solution. Sugar composition of each fractions in gel filteration of purified $H_2O$ polysaccharide suggests that the xyloglucan can be extracted with $H_2O$ from differentiating xylem.

• 한국식품저장유통학회지
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• 제30권5호
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• pp.785-796
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• 2023

The aim of this study was to elucidate chemical structures and rheological properties of arabinogalactans (AGs) isolated from three legumes including black gram (BG), great northern bean (GNB), and California small white bean (CSWB). The ratio of galactose to arabinose (G/A) in three legumes increased in the order of BG > GNB > CSWB. The rheological measurements of 1-5% (w/v) AG solutions revealed Newtonian and non-Newtonian flow behaviors. BG exhibited yield stress, indicating plastic behavior. Small-amplitude oscillatory tests indicated viscoelastic properties of BG, GNB, and CSWB ranging from solid-like, paste-like, and liquid-like behaviors, respectively. Small-strain oscillatory tests were conducted to assess the structure recovery of the AGs after pre-shearing. G" values of BG and GNB increased, but those of CSWB remained constant after shearing. These results suggest that the chemical structures of the AGs, particularly their G/A ratios, influence their rheological properties.

• Preventive Nutrition and Food Science
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• 제6권3호
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• pp.180-186
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• 2001

Bone marrow cell proliferating arabinogalactan-like polysaccharide (ALR-3IIa-1-1) has been purified from rhizomes of Atractylodes lancea DC. In order to characterize the essential structure of ALR-3IIa-1-1 for expression of the activity, sequential enzymatic digestion using ego-$\alpha$-L-arabinofurasidase (AFase) and ego-$\beta$-D-(1longrightarrow3)-galactanase (GNase) was employed. After ALR-3IIa-1-1 was digested with the AFase, the GNase digestion cleaved only 10% and 23% of 3-linked and 3,6-branched galactose, respectively, from arabinose-trimmed ALR-3IIa-1-1 (AT-ALR-3IIa-1-1), and gave small amounts of intermediate size (AT-G-2) and shorter oligosaccharides (AT-G-3) fractions in addition to a large amount of the GNase resistant fraction (AT-G-1). When AT-G-1 was redigested gradually with the AFase and GNase, it released trace amounts of oligosaccharides in addition to a large amount of the resistant fraction. When the final enzyme-resistant fraction from AT-G-1 was digested simultaneously with both AFase and GNase, the resistant fraction was significantly degraded into two long fragments (3AT-3G-1 and 2). The mixture of digestion products from the first GNase digestion of AT-ALR-3IIa-1-1 showed a significantly decreased bone marrow cell proliferation activity to about 30% of the activity of ALR-3IIa-1-1, but the GNase resistant fraction (AT-7-1) still had significant activity. Although the second gradual enzymatic digestion of AT-G-1 showed a marginal decrease in activity, the resulting fragments (3AT-3G-1 and 2) by the final simultaneous enzymatic digestion lost most of the activity. Component sugar, methylation and FAB-MS analyses indicated that the digestion products (AT-G-21 AT-G-31 2AT-2G-2 and 2AT-2G-3) released from AT-ALR-3IIa-1-1 by the sequential enzymatic digestion contained galactose-containing oligosaccharides mainly comprising 6-linked galactose, that some of which were partially arabinosylated, and these oligosaccharides were attached to $\beta$-D-(1longrightarrow3)-galactan backbone in its non-reducing terminal side as side chains.

• 식물조직배양학회지
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• 제25권6호
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• pp.477-485
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• 1998

감자 plastid 형질전찬을 위한 새로운 DNA 절편을 확보하고자, 감자의 trnK-matK 유전자를 PCR 방법으로 클로닝하고 특성을 조사하였다. 염기서열 분석을 통하여 trnK-matK 유전자에는 두 종류의 polymerase 인지부위[Prokaryotic site(plastid encoded polymerase)와 eukaryotic site (nuclear-encoded polymerase)]가 족재함을 알 수 있었다. 이 사실은 trnK-matK 유전자의 발현이 광합성조직과 비광합성조직에서 서로 다른 polymerase에 의하여 조절됨을 시사하였다. 한편 MatK의 아미노산서열을 분석한 결과 식물에 따라 아미노산 identity가 39-75%로 다양하였으나, 감자와 담배는 98%의 아주 높은 identity를 보였다. Northern분석을 통하여 포장과 기내에서 생육된 감자 식물체 모두에서, trnK-matK 의 전사 수준이 잎에서 높고 괴경에서는 낮음을 알 수 있었다. 한편 잎에서의 16s rDNA의 전사수준은 괴경에 비해 약 50배 높았다. 이것으로 미루어보아 괴경에서 수준이 낮을 것은, 괴경에서는 plastid genome copy 수가 적거나 plastid 수가 적기 때문으로 추정된다. 이상의 결과로서 엽록체와 amyloplst 모두에서 trunK-matK 유전자가 활발하게 발현되고 있음을 알 수 있었다. Plastid genomic DNA의 Southern 분석을 통하여 trnK는 1 copy로 존재하고, matK는 trnK intron을 포함하고 있음을 확인하였다. 따라서 감자 plastid형질전환의 새로운homologous recombination 부위로 trnK-matK유전자를 이용할 수 있을 것이다.

• Journal of the Korean Wood Science and Technology
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• 제30권4호
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• pp.8-16
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• 2002

본 연구는 자기가수분해전처리를 통하여 반응성이 높은 고순도 셀룰로오스기질을 제조하기 위하여 수행되었다. 공시재의 일반 화학조성은 일본잎갈나무와 신갈나무간에 큰 차이가 있음을 알 수 있었다. 추출물함량은 일본잎갈나무가 신갈나무보다 상당량 많았다. 특히 냉·온수 추출물함량은 2.5~3.5배 많았다. 이러한 추출물함량의 큰 차이는 일본잎갈나무에는 arabinogalactan이 많이 함유되어 있기 때문인 것으로 사료된다. 리그닌함량은 신갈나무가 잎갈나무바다 5% 정도 낮았으며, 그 대신 홀로셀룰로오스 및 펜토산함량이 각각3% 정도 높은 값으로 나타났다. 22 kg/cm² 수증기압력에서 5~60분간의 자기가수분해 전처리과정에서 glucose 함량에는 변화가 없었으나, hemicellulose 및 lignin 함량은 급력한 변화를 보였다. 전처리과정에서 가수분해물의 pH는 3까지 저하되었으며, 이러한 경향은 신갈나무 및 일본잎갈나무에서 동일하게 나타났다. Sodium chlorite 및 sulfite 혹은 bisulfite 전처리 후 자기가수분해가 리그닌함량이 낮은 고순도셀룰로오스기질의 제조에 효과적이었다. 특히 자기가수분해처리재를 알칼리 및 산소-알칼리 2단처리함으로서 0~0.2%의 리그닌함량을 가지는 고순도기질을 제조할 수 있었다.

• 생약학회지
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• 제27권3호
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• pp.254-261
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• 1996

A potent immuno-stimulating activity was detected from the watersoluble and ethanol-precipitated crude extract (AG-1) of the root of Angelica gigas Nakai. The crude extract was fractionated into two fractions, an acidic AG-2 and a neutral AG-3 fraction by DEAE-cellulose adsorption. The two fractions contained polysaccharides of which M.W. were 10 Kdal and >2,000 Kdal respectively, proteins, and various inorganic components. The immunostimulating activities of two fractions were not reduced by proteinase K, acid or alkali treatment. The polysaccharides obtained from the root of A. gigas were mainly composed of arabinose, galactose, and galacturonic acid. These results indicated that immuno- stimulating components of the root of A. gigas was a kind of pectic polysaccharides or arabinogalactans.

• 한국식품저장유통학회지
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• 제3권1호
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• pp.93-104
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• 1996

The cell wall components of fruit include cellulose. hemicellulose, pectin, glycoprotein etc., and the cell wall composition differs according to the kind of fruit. Fruit softening occurs as a result of a change in the cell wall polysaccharides : the middle lamella which links primary cell walls is composed of pectin. and primary cell walls are decomposed by a solution of middle lamella caused due to a result of pectin degradation by pectin degrading enzymes during ripening and softening, During fruit ripening and softening, contents of arabinose and galactose among non-cellulosic neutral sugars are notably decreased, and this occurs as a result of the degradation of pectin during fruit repening and softening since they are side-chained with pectin in the form of arabinogalactan and galactan Enzymes involved in the degradation of the cell wall include polygalacturonase, cellulose, pectinmethylesterase, glycosidase, etc., and various studies have been done on the change in enzyme activities during the ripening and softning of fruit. Among cell wall-degrading enzymes, polygalacturonase has the greatest effect on fruit softening, and its activity Increases during the maturating and softening of fruit. This softening leads to the textural change of fruit as a result of the degradation of cell wall polysaccharides by a cell wall degrading enzyme which exists in fruit.

• 한국식품과학회지
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• 제51권3호
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• pp.278-285
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• 2019

Tomato (Lycopersicon esculentum) is widely known for its beneficial effects on human health. To investigate the beneficial effects of polysaccharides from cherry tomato, cherry tomato polysaccharides (CTP) were prepared, the component sugars were analyzed, and the immunomodulatory activities in RAW 264.7 macrophages were assessed. CTP mainly contained arabinose (Ara) and galactose (Gal), suggesting that CTP might be enriched with an arabinogalactan (AG) moiety. The Ara and Gal present in CTP are likely components of AG-II (35.4%), namely $arabino-{\beta}-(3,6)-galactan$. To investigate the immunomodulatory activity of CTP, cytokine levels and iNOS2, COX-2, and $NF-{\kappa}B$ protein levels were analyzed, and $NF-{\kappa}B$ nuclear translocation and phagocytosis were observed by immunofluorescence. CTP significantly increased the levels of $TNF-{\alpha}$, MCP-1, and IL-6. CTP also increased iNOS2 and COX-2 expression as well as $NF-{\kappa}B$ nuclear translocation in RAW 264.7 cells. CTP significantly stimulated phagocytosis activity. These results showed that CTP stimulates macrophage activity, which can boost the innate immune response. CTP with high AG-II content could be used as a prebiotic to strengthen immunity.