• Applied Chemistry for Engineering
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• v.23 no.6
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• pp.515-520
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• 2012

In this review, the fabrication of silicon based memory capacitor and organic memory thin film transistors (TFTs) was discussed for their potential identification tag applications and biosensor applications. Metal or non-metal nanoparticles (NPs) could be capped with chemicals or biomolecules such as protein and oligo-DNA, and also be self-assembly monolayered on corresponding target biomolecules conjugated dielectric layers. The monolayered NPs were formed to be charging elements of a nano floating gate layer as forming organic memody deivces. In particular, the strong and selective binding events of the NPs through biomolecular interactions exhibited effective electrostatic phenomena in memory capacitors and TFTs formats. In addition, memory devices fabricated as organic thin film transistors (OTFTs) have been intensively introduced to facilitate organic electronics era on flexible substrates. The memory OTFTs could be applicable eventually to the development of new conceptual devices.

• Journal of the Korea Fashion and Costume Design Association
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• v.9 no.2
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• pp.85-92
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• 2007

This study focused on bean-juice treatment method which have dyeing property to indigo, yellow soil, sappan wood, cochineal and also on the possibility of applying to mordanting. This is different from the active mordanting using chemicals. Natural mordants with development of dyeing are not harmful, also are the medicines for disease. Limestone and ash neutralize the acidic soil. bean-juice protein adhere to cellulose surface and change the physical properties of protein so that coloring of dye is better than before and film non-soluble in water is made. Therefore the color made from bean-juice process lasts after washing. This study try to show one of the ways to improve the current method using the heavy metal which can have bad effects for environment and human being. Bean-juice(raw bean, heated bean) treatment method can be the way to fix the natural dyeing problem of bad dyeing. Bean-juice had been treated under various condition with pre-treatment, post-treatment and raw bean, heated bean. Following results are obtained in this study. In the case of Indigo dyeing, pre-treatment of heated bean shows the biggest difference of color. In the case of yellow soil dyeing, pre-treatment of raw bean-juice shows the biggest gap of color. Pre-treatment of heated bean in sappan wood dyeing case and post-treatment of raw bean show bigger color difference than pre-treatment of raw bean. In cochineal dyeing, raw bean pre-treatment shows the biggest color difference.

• Molecules and Cells
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• v.43 no.3
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• pp.298-303
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• 2020

Cryo-electron microscopy (cryo-EM) is now the first choice to determine the high-resolution structures of huge protein complexes. Grids with two-dimensional arrays of holes covered with a carbon film are typically used in cryo-EM. Although semi-automatic plungers are available, notable trial-and-error is still required to obtain a suitable grid specimen. Herein, we introduce a new method to obtain thin ice specimens using real-time measurement of the liquid amounts in cryo-EM grids. The grids for cryo-EM strongly diffracted laser light, and the diffraction intensity of each spot was measurable in real-time. The measured diffraction patterns represented the states of the liquid in the holes due to the curvature of the liquid around them. Using the diffraction patterns, the optimal time point for freezing the grids for cryo-EM was obtained in real-time. This development will help researchers rapidly determine high-resolution protein structures using the limited resource of cryo-EM instrument access.

• Membrane Journal
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• v.31 no.5
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• pp.293-303
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• 2021

Separation membranes used in water filtration, protein purification or biomedical filtration device frequently undergo membrane fouling for several reasons. The formation of biofilm on the membrane surface by bacteria causes a severe problem for durability of the membrane. For the protein separation, the membrane pores get blocked due to surface hydrophobicity of the membrane. There are several approaches controlling the membrane fouling and one of them is the incorporation of silver nanoparticles. Antibacterial properties of silver nanoparticles are well known and thus widely used in several applications. In this review, we have focused on the membranes where silver nanoparticles or its derivatives are either incorporated in the active layer of thin film composite membranes or uniformly distributed throughout the whole membranes.

• Journal of Sericultural and Entomological Science
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• v.2
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• pp.1-31
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• 1962

The purpose of this treatise is to prove the presence of cystine in silk fiber through wide sampling throughout all the sericultural processes of Bombyx mori.; also to show that disulfide cross linkages exist in the silk fiber. The conclusions reached were as follows: 1. Crystalline cystine was obtained from silk fibroin using Folin's Method. 2. Analytical data showing the cystine content of silk fiber and its related materials were obtained using Sullvan's Method as follows: Material Percent Cystine A. Mulberry leaf protein 0.175 B. Silkworm egg 0.33 C. Silkworm Body, matured, fat extracted, without silk gland 0.41 D. Silk gland, matured 1.23 E. Silkworm feces none F. Silkworm pupa, fat extracted 0.30 G. Silkworm moth, fat extracted 0.60 H. Raw Silk 0.22 I. Fibroin 0.175 J. Sericin 0.30 3. The presence of cystine in the silkworm was substantiated the existence of 0.175 % methionine in mulberry leaves and 0.12% methionine in the silk gland. 4. Part of the sulfhydryl compounds in the silk gland is believed to transfer to serine and methionine, with the former being secreted into the liquid silk finally as silk fiber and the latter used for nutritive purposes in the growing of silk gland tissue. 5. The cystine content is variable by mulberry species, silkworm species, sex, breeding process, and other culturing environments. 6. Hybrid silkworms require more nutritive amino acids for effective growth than the original parents, and secrete less of them as silk fiber. 7. From such an observation, the amino acid composition of silk fiber is believed to be fairly flexible. Cystine if included in the amorphous part of the fiber, especially in sericin. 8. The result from enriching the silkworm diet with pure cystine or wool cystine did not result in any advantage, therefore it is believed that the natural cystine and methionine contents in the mulberry leafaregoodenoughforsilkwormnutrition. 9. The disulfide cross linkage in silk fiber was verified by using the Harris Method. Contraction took place following the treatment of the fiber with various salts and acids. Comparisons were made with wool fiber. 10. During these experiments, the fibrious structure of silk fiber and the net-globular liquid form were photographed microscopically. It is believed that the globules of liquid silk are net-formed by the inter attraction of the OH ion of the globular peptide and the H ion of water as shown by the hair cracking behavior of the film. The net-globular protein precipitation from the mulberry protein solution showed that mulberry is a proper diet for the formation of fibrous protein in the silk fiber. 11. The significance of the presence of cystine in silk fiber as emphasized in this paper should result in modification of the general conception that cystine is absent from this fiber. NOTICE: A part of this treatise was presented at the annual Korea Sericultural Society meeting held in 1961.

• Journal of Applied Biological Chemistry
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• v.54 no.3
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• pp.166-170
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• 2011

Silk fibroin, a natural protein produced by silkworm, is a good biomaterial which has biodegradability and biocompatibility. To ascertain the effects of silk fibroin on cell growth, silk fibroin films were prepared using silk fibroin aqueous solutions of various concentrations. We investigated the attachment, proliferation, morphology of the cells and the expression levels of genes related to cell attachment and growth on the silk fibroin films. When the cells were cultured on the 0.1 and 1% silk fibroin film, the cell adhesion ability was very excellent. Particularly, overall cell growth on the 1% silk fibroin film was definitely superior to the others. Also, expression levels of genes related cell growth were increased on the 0.1 and 1% silk fibroin film. These results suggest silk as a material for medical applications.

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.128-138
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• 1985

This study was conducted to elucidate the shelf-life and quality changes in relation to biochemical components in leaf lettuce (Lactuca sativa L.). The shelf-life of leaf lettuce at room temperature was 2 to 3 days. But it was extended to 3 weeks by packaging in a 0.01 mm thick polyethylene film sack when stored at $3^{\circ}C$. The ascorbic acid contents of fresh leaf lettuce was 25 mg per 100 gram fresh weight. The acid at room temperature was almost destroyed after 4 days storage. But the contents of ascorbic acid at $3^{\circ}C$ maintained about 50 to 60% of the initial level in packaging of polyethylene film sack after 8 days storage. The content of chlorophyll was greatly decreased at room temperature but no significant changes were found at $3^{\circ}C$. The changes of total sugar and reducing sugar contents during storage were not very different between treatments. The contents of alkali soluble protein and free amino acid gradually increased in the treatments of polyethylene film sack packaging during storage in general, but the contents decreased after the increase in control treatment. Nucleic acid content, peroxidase and polyphenoloxidase activities were measured and discussed in relation to the leaf senescence.

• Korean Journal of Agricultural Science
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• v.13 no.1
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• pp.123-129
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• 1986

These studies were conducted to elucidate the effect of storage conditions on the changes of chemical components in fruit bodies of oyster mushroom(Pleurotus ostreatus), and the results obtained were as follows. 1. The fruit bodies of oyster mushroom sealed with polyethlene film 0.03 mm thickness maintained their freshness for 15 days at $1^{\circ}C$, 10 days at $5^{\circ}C$ and 3 days at $20^{\circ}C$. 2. The respiration rates of the fruit bodies grown in the rice-straw substrate was 29.7mg $CO_2/kg$ F.W/hr. at $1^{\circ}C$, 32.7mg at $5^{\circ}C$, and 46.3mg at $20^{\circ}C$ during the storage, respectively. The respiration rate showed the highest level at the second day during the storage. 3. The contents of total and reducing sugar during the storage of oyster mushroom rapidly increased at $5^{\circ}C$ until the fifth day following slowly decreased. 4. The content of protein in the oyster mushroom was reduced during the storage, while the free amino acid slightly increased. 5. The change of RNA and DNA contents during the storage of oyster mushroom showed inconsistency on the temperature and the storage period.

• Journal of Ginseng Research
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• v.26 no.3
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• pp.145-150
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• 2002

The changes in sensory characteristics, physical and chemical properties of raw ginseng (4-year-root, 50 g/root) were investigated when they were packaged individually in a soft film bag (ONY/LDPE/L-LDPE ; 200$\times$300 ㎜, 90 ㎛) and stored at 25$\^{C}$ for twenty days. Seventy-five percentages of sixty raw ginseng samples were adulterated and the most phenomenon of adulterating the raw ginseng was softening. Softened ginsengs were softer and stickier and they had stronger pungent and sour odors, stronger sour and sweet tastes than normal ginseng but had weaker ginseng and fresh odors. In addition, softened ginsengs exhibited lower hardness and pH, lower contents of diol-type ginsenosides, lower ratios of unsaturated fatty acids to saturated fatty acids and higher contents of water-soluble pectins than normal ginseng while contents of moisture, crude protein, ether-soluble materials and crude ash of the softened ginsengs were similar to those of normal ginseng.

• Korean Journal of Food Science and Technology
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• v.6 no.2
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• pp.109-115
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• 1974

Milssal is a polished, partially gelatinized pressed wheat grain and it is being consumed in Korea. This study was conducted to establish 2 practical means of providing needed lysine to the Korean population through fortification of Milssal. The results are summarized as follow: Lysine infusion of Milssal was significantly higher than polished wheat grain and affected by such factors as time and concentration of infusion solution. Cooking characteristics including water-uptake ratio and expanded volume were apparently better than polished wheat. After conducting the series of fortification experiments under actual manufacturing conditions. a reasonable process was chosen. In the developed process. lysine HCl solution was sprayed instead of water to the cleaned and debranned wheat grains during the regular wetting process. There was no differences in appearance and taste of Milssal before and after fortification. Fortification of the protein of Milssal with lysine has been found to bring a significant improvement in the growth rate of rats and the protein efficiency ratio. Stability remained relatively high throughout the storage period(90 days at $10{\sim}20^{\circ}C$ or 30 days at $37^{\circ}C$).