• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 1999년도 Pre-symposium of the 10th ISWPC Recent Advances in Paper Science and Technology
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• pp.375-380
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• 1999

In order to improve the optical properties of high yield pulp, bleached chemi-thermo-mechanical pulp (BCTMP) was produced from CTMP of Betula maximowicziana Regel by two staged ozone-hydrogen peroxide bleaching. This pulp was used for the evaluation of the improvement of optical properties, chemical characteristics of lignin in fiber, and the relationship between lignin and optical properties in fiber cell wall. By hydrogen peroxide treatment, the brightness was improved, but the post color number (PC No.) was not. There was little improvement on optical properties by ozone treatment, but his could be solved by using two staged ozone-hydrogen peroxide bleaching. The hydrogen peroxide treatment did not make nay change on chemical characteristics of lignin in cell wall, but by ozone treatment, it was found that the non-aromatic conjugated structure was existed in the surface of cell wall, but this could be removed by hydrogen peroxide treatment in two staged ozone-hydrogen peroxide treatment. Therefore, the optical properties was significantly improved due to the removal of non-aromatic conjugated structure.

• 한국균학회지
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• 제40권4호
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• pp.299-302
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• 2012

효모추출물 4 mg/mL를 고추유묘에 경엽 및 뿌리 관주처리 24시간 후에 salicylic acid(SA)함량을 ultra high performance liquid chromatography(UHPLC)분석방법으로 측정한 결과 yeast cell wall extract(YCWE)처리구에서 대조구의 SA처리구와 동일한 peak가 검출되어 SA가 생성 유도 되는 것으로 확인 되었다. SA는 YCWE를 경엽처리 48시간 후 20.29 ${\mu}g/g$으로 가장 높게 나타났으며 관주처리보다 약 3.7배의 높은 SA검출함량을 보였으나 처리 후 72시간부터는 점차적으로 SA함량이 감소하는 양상을 보였다.

• 한국식품과학회지
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• 제22권7호
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• pp.738-742
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• 1990

감과실의 성숙과 추숙중 세포벽의 함량은 감소하는 경향이었고, 성숙중에는 pectin질과 알칼리 가용성 hemicellulose의 함량은 증가하는 반면 산 가용성 hemicellulose와 lignin은 감소하였다. 그러나 연시에서는 pectin질과 알칼리 가용성 hemicelloluse의 감소와 산가용성 hemicellulose의 증가가 뚜렷하였다. 그리고 성숙과 추숙중에 cellulose의 함량은 증가하였으며, 생체당 세포벽 다당류의 함량은 감소하였다. 총 pectin질과 불용성 pectin질의 함량은 성숙중에는 증가하였으나 연시에서는 현저히 감소하였으며, 반면에 수용성 pectin질의 함량은 성숙과 추숙중에 증가하였다.

• The Plant Pathology Journal
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• 제27권1호
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• pp.8-13
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• 2011

The induced resistance of cucumber leaves treated with oligochitosan to the infection of the cucumber powdery mildew, Sphaerotheca fuliginea, was investigated using transmission electron microscopy. The results showed that when the plants were treated with oligochitosan and challenged with inoculum, a significant decrease of the disease occurred. The mycelial development in the treated leaves was markedly inhibited. The cytoplasm of the powdery mildew mycelium was aggregated, with its organelles disintegrated and the cytoplasm collapsed. The protoplasm in haustoria became electron-dense. Haustoria became malformed, their organelles disintegrated, the hausterial wall thickened and eventually the whole complex necrotized. The host cells produced defence structures and materials associated with infection and a hypersensitive response. The host cell wall was thickened and deeply stained; several layers of papilla structure were produced under the cell wall; dark materials were deposited between the cell wall and plasmalemma; extrahaustorial plasmalemma was deeply stained and extrahaustorial matrix appositions had large deposits of electron-dense material; the cytoplasm was disordered, host organelles disintegrated and eventually the whole host cell disintegrated and necrotized.

• Journal of Microbiology
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• 제33권3호
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• pp.228-233
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• 1995

As S. epidermidis cell was fractionated into cell wall, cell membrane, and cytoplasm, the cell membrane proved to be the most efficient absorbent for lead ion. Utrasonication was effective, when the cells were treated during their exponential growth. The amount of the lead ion adsorbed in cell membrane decreased as hydrogen ion concentration of solution increased. Protein purified from the cell membrane showed higher adsorption capacity for the lead ion than peptidoglycan, teichoic acid from cell wall, or cell membrane lipid. Modification of carboxyl groups in the membrane protein with ethylenediamine and 1-ethyl-3-carbodiimide hydrochloride resulted in a considerable decrease of lead ion adsorption capability, suggesting that the main binding site for lead ion was the carboxyl groups of protein in cell membrane.

• Journal of Plant Biology
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• 제38권1호
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• pp.25-32
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• 1995

The distribution of RNA in the anther wall of Brassica napus during male gametogenesis was followed by 3H-uridine autoradiography. Silver grain(SG) density was not above background in the anther wall just after microspore was released from tetrad callose wall. Significant accumulation of SGs occurred in tapetum, endothecium, and epidermis before microspore vacuolation. Accumulation of RNA in the tapetal cells was peak before the vaculation occurred in the microspore. With the onset of tapetal senescence at the partially vacuolated microspore stage, SGs decreased and they completely disappeared in the tapetum at the bicelled pollen stage. Accumulation of RNA in the endothecial cells was peak after the microspore mitosis and continued just after the generative cell mitosis. Appreciable SGs also occurred in cells of epidermis from nonvacuolate microspore stage to bicelled pollen stage. During this period, SG density was almost same and was not high as compared with tapetum or endothecium. At tricelled mature pollen stage, no incorporation occurred in anther wall. SGs were found mostly over the nucleouls and chromation of the cell nuclei.

• Journal of Microbiology and Biotechnology
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• 제8권5호
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• pp.501-508
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• 1998

An alkalophilic mi.croorganism (strain YB380), which produces yeast cell wall hydrolase extracellulary, was isolated from Korean soil. The rod-shaped cells were 0.3~0.4 by 2~4${\mu}{\textrm}{m}$ long, motile, aerobic, gram-positive, and spore-forming. The color of the colony was light yellow. The temperature range for growth at pH 9.0 was 25 to $45{\circ}C, with optimum growth at $35{\circ}C. The pH range for growth at $35{\circ}C was 8 to 11 with an optimum pH of 9.0. Therefore, the strain YB380 is an obligate alkalophile. The 16S rRNA of strain YB380 has a 99% sequence similarity with that of Bacillus alcalophilus. On the basis of physiological properties, cell wall fatty acid composition, and phylogenetic analysis, we propose that the isolated strain is Bacillus alcalophilus. The yeast cell wall hydrolase from Bacillus alcalophilus subsp. YB380 has been purified and partially characterized. The molecular weight was estimated to be 27,000 daltons with an optimum temperature and pH of $60{\circ}C and 9.0, respectively. The N-terminal amino acid sequence of the enzyme was analyzed as Gln- Thr- Val- Pro- Trp- Gly- Ile- Asn- Arg- Val.

• Asian-Australasian Journal of Animal Sciences
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• 제21권6호
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• pp.824-830
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• 2008

Sodium hydroxide (SH) or ammonium bicarbonate (AB) were applied to rice straw to investigate the effects on histological change of stem tissue or cell wall before and after in sacco degradation using a scanning electron microscope (SEM) and a transmission electron microscope (TEM). The SEM revealed that, the parenchyma and vascular bundles were distorted by treatment with SH at 30 or 45 g/kg straw dry matter. Faultage between phloem of large vascular bundles and parenchyma occurred with further increasing SH to 60 or 75 g/kg. The cell wall in these stem tissues was crimped when observed by TEM. However, only parenchyma and large vascular tissues were slightly distorted in AB-treated stem. For untreated and AB-treated stems, the initiation of observable ruminal degradation of cell wall was prolonged from 12 h for inner parenchyma to 24 h for sclerenchyma and to 48 h for phloem of small vascular bundles, while the outer epidermis was intact even at 72 h. For SH-treated stem, however, the cell wall from all of the investigated tissues, epidermis, small vascular bundles, sclerenchyma, and parenchyma started to be degraded at 12 h incubation. These results indicate that SH treatment contracts rice straw stem leading to an improvement in rumen degradation, and that the degradation of SH-treated stem is bilateral from inner and outer surface simultaneously.

• Journal of Microbiology and Biotechnology
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• 제28권10호
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• pp.1760-1768
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• 2018

The type strain Bacillus subtilis subsp. subtilis KCTC $3135^T$ was deeply sequenced and annotated, replacing a previous draft genome in this study. The tar and tag genes were involved in synthesizing wall teichoic acids (WTAs), and these genes and their products were previously regarded as the distinguishing difference between B. s. subtilis and B. s. spizizenii. However, a comparative genomic analysis of B. subtilis spp. revealed that both B. s. subtilis and B. s. spizizenii had various types of cell walls. These tar and tag operons were mutually exclusive and the tar genes from B. s. spizizenii were very similar to the genes from non-Bacillus bacteria, unlike the tag genes from B. s. subtilis. The results and previous studies suggest that the tar genes and the tag genes are not inherited after subspecies speciation. The phylogenetic tree based on whole genome sequences showed that each subspecies clearly formed a monophyletic group, while the tree based on tar genes showed that monophyletic groups were formed according to the cell wall type rather than the subspecies. These findings indicate that the tar genes and the presence of ribitol as a cell-wall constituent were not the distinguishing difference between the subspecies of B. subtilis and that the description of subspecies B. s. spizizenii should be updated.

• 한국식품과학회지
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• 제27권6호
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• pp.934-938
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• 1995

Autoclaving, microwaving, 압출성형 등의 열 및 기계적 에너지에 대한 밀기울 세포벽의 반응성을 구명하기 위하여 수용성 분획의 특정을 연구하였다. 수용성 분획의 화학적 분석과 겔여과 크로마토그래피 결과에 의하면 밀기울에 포함되어 있는 전분의 호화가 가장 중요한 수용화 기작으로 작용하며, 이 과정에서 비전분성 세포벽 구성물질의 수용화도 일어냐는 것으로 밝혀졌다. 수용성의 비전분 다당류의 GC 분석결과 적용된 열처리 과정에서 세포벽의 arabinoxylan 부위가 많이 수용화되는 현상을 보였다. 특히, 고온파 고전단력을 동시에 제공하는 압출성형은 밀기울의 수용화에 가장 효율적이었으며, 또한 상대적으로 고분자량의 비전분성 구성성분을 수용 화시켰다.