• Journal of Sericultural and Entomological Science
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• v.43 no.2
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• pp.116-124
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• 2001

To improve the functional properties as a food, silk fibroin was phosphorylated with STMP In the phosphorylation reaction of silk fibroin, the degree of phosphorylation was increased with high alkali index and treatment temperature. Depending on treatment time and concentration of STMP it was rapidly increased up to 1hr. and 50%, but slowly above that time and 100%. It was indicated in the results of FT-IR analysis and $\^$31/p NMR spectroscopy of phosphorylated fibroin that it had a close ∝-helix and poly-phosphate structure. The more phosphorylation of fibroin made more turbidity, foam expansion and foam stability, but less solubility. Emulsifying activity was increased up to P100, but slightly decreased above Pl00 and emulsifying stability was constantly increased on the progressing of phosphorylation.

• Journal of Microbiology and Biotechnology
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• v.31 no.4
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• pp.592-600
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• 2021

Probiotics can be processed into a powder, tablet, or capsule form for easy intake. They are exposed to frequent stresses not only during complex processing steps, but also in the human body after intake. For this reason, various coating agents that promote probiotic bacterial stability in the intestinal environment have been developed. Silk fibroin (SF) is a material used in a variety of fields from drug delivery systems to enzyme immobilization and has potential as a coating agent for probiotics. In this study, we investigated this potential by coating probiotic strains with 0.1% or 1% water-soluble calcium (WSC), 1% SF, and 10% trehalose. Under simulated gastrointestinal conditions, cell viability, cell surface hydrophobicity, and cell adhesion to intestinal epithelial cells were then measured. The survival ratio after freeze-drying was highest upon addition of 0.1% WSC. The probiotic bacteria coated with SF showed improved survival by more than 10.0% under simulated gastric conditions and 4.8% under simulated intestinal conditions. Moreover, the cell adhesion to intestinal epithelial cells was elevated by 1.0-36.0%. Our results indicate that SF has positive effects on enhancing the survival and adhesion capacity of bacterial strains under environmental stresses, thus demonstrating its potential as a suitable coating agent to stabilize probiotics throughout processing, packaging, storage and consumption.

• Food Science and Industry
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• v.55 no.2
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• pp.154-165
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• 2022

Humans have been breeding the mulberry silkworm for the long period of time to obtain silk fabric and nutrient-rich pupae. Currently, silkworm larvae, pupae, and silk-Fibroin hydrolysates are registered as food raw materials, while silkworm feces and Bombyx batryticatus are registered as Korean traditional medicines. Among sericulture products, individually recognized health functional food ingredients include silk-protein acid-hydrolysates for immunity enhancement, Fibroin-hydrolysates for memory improvement, and freeze-dried 5^th instar and 3^rd-day-silkworm powder for lowering-blood sugar. Recently, HongJam produced by steaming and freeze-drying mature silkworms were reported to have various health-promoting effects such as preventing the onset of Alzheimer's disease and Parkinson's disease, enhancing gastro-intestinal functions, improving skin-whitening and hair growth, and extending healthspan. By consuming silkworm products with various health-promoting effects, it is possible to increase the healthspan of human beings, thereby reducing personal and national medical expenses, resulting in increasing the individual's happiness.

• Journal of the Korean Home Economics Association
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• v.38 no.9
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• pp.119-130
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• 2000

The purpose of this study was to confirm the possibility of screen printing with Natural dyes. The coloring matter such as sappan wood was used in order to obtain the colorant powder through the processes of extraction, low pressure concentration and the spray dry. After the screen printing on silk and cotton fabrics with colorant, K/S value changes of color and color fastness were measured. The main resets were as follows : 1. The viscosity of printing thickeners of sappan wood powder was about 15,200 cps, and the highest K/S value of the fabrics printed with sappan wood was obtained at 90$\pm$2$\^{C}$ of steaming temperature and 80 minutes of steaming time. 2. For the fabrics printed with sampan wood, adding of urea was not effective, since the more the concentration of urea increased, the more K/S values decreased. 3. For the natural dyes printing, the more the concentration of colorants increased, the more K/S values increased. In general, the K/S values of the printed fabrics were higher when treated with mordants rather than without mordants. Specifically, the λmax sappan wood was 520∼570 nm, and the K/S value was highest when treated with Cu mordant and lowest when treated with Sn. 4. Generally, the color fastness was relatively fair.

• Journal of the Korean Ceramic Society
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• v.48 no.1
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• pp.106-109
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• 2011

In order to fabricate 8YSZ thick film by silk screen printing, YSZ(yttria-stabilized zirconia) commercial powder was used as starting materials. Paste for screen printing was made by mixing 8YSZ powder and organic vehicles. 8YSZ thick film was formed on $Al_2O_3$ substrate. The crystal structure, and microstructure were investigated. Grain size of 8YSZ was increased with increasing calcination temperature and rapid grain growth was shown after calcination at $1300^{\circ}C$. Microstructure showed the mixture of large and small grain size after $1400^{\circ}C$ sintering. Shrinkage rate of 8YSZ thick film sintered at $1400^{\circ}C$ was more than 40%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.1
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• pp.41-50
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• 2012

The study was carried out to analyze the relationship between analysis of antioxidant activity and the level of functional components according to particle size of corn silk. Particle size was classified into 5 groups. By particle size distribution and color difference, the total phenol content and DPPH radical scavenging activity were observed. The particle sizes of corn silk were $199.17{\mu}m$, $178.27{\mu}m$, $85.48{\mu}m$, $27.4{\mu}m$ and $20.97{\mu}m$, respectively. The lightness of colored pigments was increased when the particle size was decreased. The contents of free sugar (fructose, glucose, galactose, sucrose, and maltose) of corn silk were analyzed using a HPLC. The total phenol contents by the particle sizes of corn silk were 2.01 mg/g, 2.02 mg/g, 2.06 mg/g, 2.26 mg/g and 2.26 mg/g, respectively. DPPH radical scavenging activities of samples were 21.00%, 21.75%, 22.90%, 24.35% and 23.67%, respectively. Antioxidative activities of Trolox and Fe(II) in corn silk were measured by ferric reducing antioxidant power (FRAP) assay and Trolox equivalent antioxidant capacity (TEAC) assay. TEAC values of samples were $2.36{\mu}mol$ TE / g dw, $2.81{\mu}mol$ TE / g dw, $3.20{\mu}mol$ TE / g dw, $3.36{\mu}mol$ TE / g dw, and $3.44{\mu}mol$ TE / g dw, respectively. FRAP values of samples were $11.67{\mu}mol$ Fe(II) / g dw, $12.80{\mu}mol$ Fe(II) / g dw, $13.43{\mu}mol$ Fe(II) / g dw, $13.85{\mu}mol$ Fe(II) / g dw and $15.95{\mu}mol$ Fe(II) / g dw, respectively. Total phenolic content and antioxidantive activities based on FRAP assay and TEAC assay were increased with decreasing particle size. In addition, DPPH radical scavenging activity was also increased. A significant correlation was also noted between DPPH radical scavenging activities and the content of phenolic compounds.

• International Journal of Industrial Entomology and Biomaterials
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• v.18 no.2
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• pp.63-67
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• 2009

To increase utilities as functional materials, 173 strains of silkworm genetic resources in the form of silkworm powder were evaluated for antioxidative capacity, with minilum L-100 device and ARAW-KIT (anti-radical ability of water soluble substance). Silkworm powder was prepared with freezing method from silkworms at 5th instar 3rd day larvae. All strains of silkworm powder were prepared with 80% methanol extraction. The data of pupation rate, longevity of silkmoth with origin and voltinism were used for data base of silkworm genetic resources. The weight of a silkworm larva with freezing method at 5th instar 3rd day was measured. The average of antioxidative capacity of 173 silkworm strains was 429.68 nmol. The analysis of correlation among variables was significant, showing negative correlation of the antioxidative capacity with longevity of silk moth and weight of 5th instar silkworm larva. The strains from the tropic, Europe and some other origins were comparatively high. In conclusion, short longevity and low weight of 5th instar silkworm larvae showed comparatively effective antioxidative capacity.

• Journal of Sericultural and Entomological Science
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• v.17 no.2
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• pp.155-160
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• 1975

The study was carried out to investigate the effects of various compositions of artificial diet for silkworms on the cocoon shell fibroin-hydrolyzing with the proteolytic enzyme. The obtained results are summarized as follows： 1. It was found that the fibroin-hydrolyzing ratio of the cocoon shell made by silkworms fed with artificial diets was lower than that of the cocoon shell made by silkworms fed with natural diet (mulberry leaf) 2. The amount of soybean meal in the artificial diet was negatively related to the sericin content of cocoon shell but it scarcely affected on the fibroin-hydrolyzing ratio. 3. The increase of sucrose in the artificial diet reduced the sericin content of cocoon shell but it didn't influence on the fibroin-hydrolyzing ratio. 4. A significant difference between male and female silkworms fed with artificial diets was found in the sericin content of cocoon shell but it was not approved in tile fibroin-hydrolyzing ratio. 5. The artificial diet containing 8 per cent of mulberry leaf powder increased the fbroin-hydrolyzing ratio more than that containing 10 per cent of mulberry leaf powder or that containing 8 per cent of mulberry leaf powder and a little of methionine did. 6. The artificial diet for all instars of silkworms increased the fibroin-hydrolyzing ratio more than the artificial diet for 1st to 3rd instars and natural diet (mulberry leaf) for the rest instars did.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.1
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• pp.14-21
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• 2017

Gastric ulcer is a clinical symptom characterized by inflammation of the gastric mucosa. Stress and alcohol consumption have been identified as the major cause of gastric ulcer. However, the effects of silkworms on ethanol-induced gastric ulcer have not been studied yet. The mature silkworms that are difficult to eat have become easier to ingest due to recent technological development to make steaming and freeze-drying mature silkworm larval powder (SMSP). In this study, we investigated whether three silkworm varieties, Baekokjam, Golden-silk and Yeonnokjam could alleviate ethanol-induced gastric mucosal damage in vivo. Sprague-Dawley rats pretreated with 3 SMSPs (0.1 or 1 g/kg BW) or normal diet (AIN-76A) were exposed to absolute ethanol (3 g/kg BW, 3 h) by oral gavage. Morphological examination included ulcer index as a measurement of hemorrhages and hematoxylin and eosin staining was performed to analyze the severity of gastric ulcer. Results of macroscopic examination suggested that all 3 SMSPs pretreatment significantly protected gastric mucosa against ethanol-induced damage. Microscopic observations demonstrated significant mucosal erosion and inflammation in ethanol-treated rats, which was abrogated in rats pretreated with 3 SMSPs. In addition, pretreatment with all 3 SMSPs showed significant decreases the expression of pro-inflammatory mediators, IL-6 and cyclooxygenase-2. Among SMSP from 3 varieties of silkworm, preadministration of 1 g/kg Baekokjam SMSP showed the most effective protective effect against ethanol-induced gastric ulcer. These results suggest that Baekokjam SMSP can be a potential gastroprotective agent against ethanol-induced gastric ulcer.

• Textile Coloration and Finishing
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• v.13 no.4
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• pp.241-248
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• 2001

Natural indigo dyeing has been used mainly on cellulosic fibers and silk during the course of history in Korea. In order to extend the usage of this one of the most important natural dyes, its dyeability on wool fabrics has been studied to find out the optimum dyeing condition for wool fiber which is susceptible to alkaline medium. The dyeing method used was hydrosulphite vat of extracted dye. K/S values of dyed fabrics were investigated to analyze the dyeability of natural indigo on wool fibers and colors were measured through $L^*,\;a^*,\;b^*$ and Munsell Values. Highest K/S values were obtained at the temperature of 60(C and pH 7 to 8. The Munsell Values for hue of wool fabrics dyed with extracted indigo powder using hydrosulphite vat fell mostly in PB range. As the dyebath pH increased, blueness increased. Different dyeing conditions resulted in change of colors of dyed fabrics due to the difference in amounts of indigotin and indirubin contents within the dyed fiber as shown by HPLC.