• Journal of Sericultural and Entomological Science
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• v.45 no.1
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• pp.58-65
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• 2003

This study was carried out to investigate the characteristics of the soluble sericins after degumming and after hydrolysis of insoluble sericin with various enzymes. Physical and chemical characteristics of the soluble sericins were also studied and pack test was conducted. Electro donating ability of the various sericins became higher as high＞low＞KP＞PP＞PA. In FT-IR analysis, the band of insoluble sericin at 3,285cm$\^$-1/ was shifted to the lower wavelengths in soluble sericins. The intensity of the amide II band was reduced and shifted to lower wavelengths as a result of hydrolysis. In DSC analysis, all sericins showed endothermic peaks around 200$^{\circ}C$ and insoluble sericin showed another peak at 250$^{\circ}C$. The endothermic peak of the insoluble sericin was found at higher temperature compared with those of the soluble sericins which showed at 300$^{\circ}C$. Whiteness of the various sericins became higher as low＞high＞PP＞PA＞PK＞IN and yellowness were PK＞PA＞PP＞low＞high. In pack test, the skin packed with the non-woven fabric treated with the various sericins was more smooth and less oily.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.57-57
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• 2003

세리신은 실크의 25%를 차지하는 단백질이다. 대부분 정련과정을 통하여 제거되지만 이를 재활용하려는 시도는 꾸준히 진행되고 있다. 특히 천연보습인자 (NMF)인 세린을 많이 함유하고 있어 화장품 분야로의 응용이 기대되며, 최근에는 세리신을 합성섬유에 코팅하는 skin care 가공도 개발되었다. 그러나 세리신은 젤화가 일어나고 동결건조 후에는 용해도가 감소하는 경향이 있다. (중략)

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.93-98
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• 2017

The fixing behaviors of raw silk yarns treated with melamine and formaldehyde at a molar ratio of 1:3 for trimethylolmelamine were investigated. Sericin was fixed during the fixing process, but a part of sericin I was removed simultaneously by hot water. The weight losses by fixing and the degumming losses by degumming greatly decreased with increasing concentrations of melamine and formaldehyde. The silk yarns fixed with 0.011 M melamine and 0.033M formaldehyde were significantly degummed due to the insufficient fixation of sericin and the alkaline hydrolysis of sericin by sodium carbonate during the degumming process. On the other hand, the silk yarns fixed with 0.055M melamine and 0.165M formaldehyde were degummed slightly (the degumming losses of 3-8%) due to the strong fixation of sericin, which might result from the many cross-linkages between the sericin I molecules, which were formed by trimethylolmelamine. Those fixed with the fixing solution containing 15% owf softener showed the lowest weight and degumming losses because under the condition of 15% owf softener, the cation of the softener can effectively form ionic bonds with the negatively charged side chain of aspartic acid in sericin. In addition, van der Waals' forces may be also formed between the hydrophobic tail of the softener and the hydrophobic region of sericin, which may help inhibit the removal of sericin I.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.2
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• pp.135-141
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• 2009

In this study, we hydrolyzed hot-water extracted sericin with single or two enzymes and investigated anti-oxidative effect on DPPH free radical and inhibitory effect on tyrosinase activity of the sericin hydrolysates. Alcalase, flavourzyme, and protamex were effective in hydrolyzing sericin. Sericin was degraded into the range of 20 ${\sim}$ 30 kDa. The sericin hydrolysate was shown to have stronger antioxidant properties than the original sericin. In the case of flavourzyme and protamex combination, the scavenging effect of sericin hydrolysate on DPPH radical was increased up to about 85 %. However, the inhibitory effect on tyrosinase activity of enzymatic hydrolysates was lower than that of the original sericin. After fractionation of sericin hydrolysates, we found that F2 and P3 fraction has higher inhibitory effect on tyrosinase activity compared to other fractions.

• Journal of the Korean Applied Science and Technology
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• v.40 no.1
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• pp.88-94
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• 2023

Sericin is a protein extracted from the cocoon and has many health benefits. This study was conducted to evaluate the anti-wrinkle and anti-inflammatory activity of sericin derived from cocoon as a cosmetic material. The antioxidant activity of sericin was measured by DPPH and ABTS assays. In addition, cell viability was confirmed in Raw 264.7 cells, which are macrophages, and the anti-inflammatory effect of sericin was investigated using the inflammatory response induced using lipopolysaccharide (LPS). It shows that sericin has antioxidant activity and can be an excellent material for anti-aging and anti-inflammatory cosmetics.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.392-398
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• 2010

The objective of this study was to assess improvements caused by silk sericin extract in blood glucose and lipid concentrations in the sera of streptozotocin(STZ, 55 mg/kg B.W., I.P. injection)-induced diabetic rats fed on experimental diets for 5 weeks. Serum concentrations of blood glucose, total cholesterol, atherosclerotic index, LDL, LDL-cholesterol, free cholesterol, cholesteryl ester ratio, triglyceride(TG) and phospholipids(PL) were remarkably higher in the diabetic group(group BSW) and STZ(I.P.)-plus-silk sericin extract group(group ESS) than in the control group(group CG, basal diet-plus-water). However, the serum concentrations of blood glucose, total cholesterol, atherosclerotic index, LDL, LDL-cholesterol, free cholesterol, cholesteryl ester ratio, TG and PL were lower in the ESS group than in the BSW group, whereas the ratio of HDL-cholesterol concentration to total cholesterol and HDL-cholesterol concentration in the ESS group were higher than in the BSW group. The activities of alkaline phosphatase(ALP) and aminotransferase(AST, ALT) in serum were lower in the ESS group than in the diabetic BSW group. The results shown above suggested that silk sericin extract effectively improves blood glucose and lipid concentrations in the sera of STZ-induced diabetic rats.

• Journal of the Korean Chemical Society
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• v.20 no.4
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• pp.309-315
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• 1976

An efficient separation method and the utilization of sericin are searched. Sericin was extracted with hot water from cocoons under atmospheric pressure. The separated sericin was gel-filtrated with Sephadex G-75 and G-150 at room temperature and at $70^{\circ}C$. The results indicated that sericin is consisted of only one fraction in elution diagram. In the graft copolymerization of acrylonitrile to sericin ceric ammonium nitrate was chosen as an initiatior. A maximum yield was obtained at certain concentration of the initiator confirming our previous experiments. Viscosity measurement of alkali-hydrolyzed graft copolymers indicated that the polyacrylonitrile graft had the molecular weight in the range of 7,000.

• Journal of Sericultural and Entomological Science
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• v.53 no.2
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• pp.92-96
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• 2015

It is known that silk protein supports effectively proliferation of cell such as insect cell and hybridoma cell. Although there are many varieties of Bombyx mori silkworm, the effect of silkworm varieties on cell proliferation has not been considered in detail. We studied that characteristics of silk cocoon obtained from Baegokjam, Kumokjam, Daeseongjam silkworm varieties and whether silk protein affected cell proliferation or not. Silk sericin was prepared under high temperature and high pressure condition. Silk fibroin was prepared using $CaCl_2:H_2O:EtOH$ with different dissolution time. As a result, there are differences in silk cocoon from different silkworm varieties about cell proliferation. The proliferation was accelerated in the presence of Baegokjam silk sericin and Kumokjam silk fibroin with 5hr dissolution time. We expect that silk proteins could be a preferable culture medium supplement for stimulating the proliferation of cell. Then, this results suggest silk as a new material for medium supplement replacing with fetal bovine serum.

• Journal of Life Science
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• v.20 no.10
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• pp.1525-1531
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• 2010

The principal objective of this study was to investigate the effects of silkworm sericin extract supplementation on the improvement of lipid compositions, blood glucose levels and enzyme activities in the serum of dyslipidemic rats. The rats were fed the experimental diet for 5 weeks. Concentrations of total cholesterol, atherosclerotic index, LDL-cholesterol, triglyceride (TG), phospholipid (PL), free cholesterol, cholesteryl ester ratio and blood glucose in serum were higher in the dyslipidemic group (group HCW) and cholesterol-plus-silkworm sericin extract intake group (group HCS) than those in the control group (group BW, basal diet-plus-water). However, the concentrations of total cholesterol, atherosclerotic index, LDL-cholesterol, TG, PL, free cholesterol, cholesteryl ester ratio and blood glucose level in serum were lower in group HCS than those in group HCW. On the other hand, the HDL-cholesterol level and the ratio of HDL-cholesterol to total cholesterol in group HCS were higher than in group HCW. The activities of alkaline phosphatase (ALP) and aminotransferase (AST & ALT) in serum were lower in group HCS than in the dyslipidemic group HCW. From the above results, it was suggested that silkworm sericin extract intake was effective in the prevention and improvement of lipid components, blood glucose level and enzyme activities in the sera of dyslipidemic rats.

• Journal of Sericultural and Entomological Science
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• v.36 no.2
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• pp.152-156
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• 1994

The sericin fixation of raw silk by formalin and glutaraldehyde mixed solutions was done and the effect of sericin fixtion by various conditions on degumming ratio, whiteness and physical properties was investigated and discusse. The obtained results were summarized as follows ; The sericin fixation by 1% formalin solution and upward, regardlles the concentration of glutaraldehyde solution, improved the whitenes of raw silk to 96% level of non fixed raw silk. The decrease of whiteness by degumming was prevented effectively by treatment of formalin and glutaraldehyde mixed solutions. The complete sericin fixation was obtained by the treatment of mixed solution including above 0.5% formalin solution. The proper treatment of sericin fixation can make increase the values of tenacity and elongation of silk.