• International Journal of Industrial Entomology and Biomaterials
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• v.31 no.2
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• pp.127-131
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• 2015

Oak silkworm, Antheraea yamamai (A. yamamai), has been used for clothing and surgical suture and considered as biomaterial due to RGD tripeptide. This paper reported the degumming conditions of A. yamamai using sodium oleate, high pressure and temperature, and sodium carbonate. Degumming ratio of A. yamamai cocoon using sodium oleate was less than 10%. High pressure and temperature treatment induced 30% weight loss of A. yamamai cocoon. The concentration, treatment temperature and time using sodium carbonate was examined and revealed the following conditions for degumming; 5% owf, 60 min at 100℃. The degummed solution was confirmed using UV and FT-IR spectrometer. Our results can be used to handle A. yamamai silkworm cocoon for further application including material processing.

• Journal of Sericultural and Entomological Science
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• v.42 no.2
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• pp.109-113
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• 2000

The preparation of skin care gauze could be make to mixing separated cellulose from waste milk pack and degummed silk fibroin fiber. Also, its wound covering and anti-bacterial activity were investigated in order to find out the enhancement of their functionality. By the 30% silk fibroin fiber including skin care gauze, the anti-bacterial activity values of Staphylococcus strain are much 4 times higher than of 0∼10% silk fibroin fiber including skin care gauze. The average yield of cellulose from waste milk pack was obtained 50-60%, and their morphologies, physical properties, modulus and biodegradation ratios are studies, respectively.

• Journal of the Korean Society of Clothing and Textiles
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• v.12 no.2 s.27
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• pp.133-144
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• 1988

Silk fabrics were degummed and dyed in one bath under the condition of high temperature and high pressure and the results obtained were summerized as follows. 1. The degumming ratio is nearly the same as that of two bath method under the normal condition and the optimal condition is for 30 minutes at $120^{\circ}C$. 2. The dyeing absorption ratio is a little lower than that of two bath method. 3. The tensile strength and elongation are hardly shown the difference between two methods. 4. The fastness of the dyed fabric of one bath method is a little better than that of two bath method. (light, washing, rubbing) 5. The stiffness of the silk fabric treated by one bath method is a little harshier compare to that of two bath method.

• Textile Coloration and Finishing
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• v.21 no.1
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• pp.67-72
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• 2009

To investigate the strong and effective sericin fixing agents and conditions, raw silk fibers were treated with the mixtures of urea-formalin, thiourea-formalin and melamine-formalin as sericin fixing agents, respectively. And the treated raw silk fibers were degummed by the degumming liquors of alkaline detergent and sodium carbonate to confirm the hardness of sericin fixation. The weight of raw silk fibers was decreased in the process of sericin fixation treating at 80$^{\circ}C$ for 60min. The effective sericin fixation was obtained by treating at $60{\sim}80^{\circ}C$ for 15min with the mixture of melamine and formalin. The mixture of melamine and formalin showed an outstanding ability of sericin fixation because the three amino groups of melamine were able to cross-link the hydroxy amino acids of sericin such as serine with the assistance of formalin.

• Textile Coloration and Finishing
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• v.18 no.6 s.91
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• pp.25-30
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• 2006

Degumming is an essential process to improve the luster and smoothness of the silk filament. Silk varieties were degummed using different methods. A number of methods, from pad-steam to specific alkaline are being used for this propose. In this paper an attempt to compare the efficiencies of different degumming processes has been made. from the results, it may be observed that when silk fabrics were pad-steam, the degree of degumming, as assessed by weight loss. When the pad-steam degumming was carried out at different pHs, adjusted using alkalies, it was observed that at higher pH the weight loss is high. Pad-steam degumming as well as star degumming was found to be superior with minimum damage to the substrate. Among the alkalis used, the sodium carbonate gives the best results, since the weight loss is almost maximum with lower strength loss by over degumming. It is also efficient from the point of view of conservation of heat energy and time as against the comparable star degumming.

• International Journal of Industrial Entomology and Biomaterials
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• v.44 no.1
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• pp.4-11
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• 2022

In this study, cocoons from different silkworm strains and rearing seasons were collected and immersed in water at elevated temperatures to investigate the effect of a wet treatment on their morphology and crystallinity. Untreated cocoons exhibited different crystallinities depending on the silkworm strain and rearing season; however, no distinct changes in their morphological structure were observed. Furthermore, after wet treatment, the differences in the crystallinities of cocoons disappeared. In addition, wet treatment of degummed silk (i.e., fibroin) did not change its crystallinity. These results indicate that different crystallinities of the untreated cocoons collected from various silkworm strains and rearing seasons are due to the different characteristics of sericin in the cocoons.

• Journal of Sericultural and Entomological Science
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• v.45 no.1
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• pp.34-45
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• 2003

Silk was treated with calcium hydroxide for degumming at different treatment times, temperatures and Ca(OH)$_2$ concentration to optimize degumming conditions in this thesis. After degumming, soluble and insoluble sericin were seperated and then the soluble sericin was characterized by measuring the average degree of polymerization (D.P.), lysinoalanine (LAL) content, DSC, and by amino acid analysis. And degummed silk fibroin was characterized by measuring tenacity and SEM. Degumming loss was increased by increasing the treatment time and temperature until about 30 minutes. After then, a slight difference was found along with treatment times at the Ca(OH)$_2$ concentrations of 0.07% and 0.1% solutions. After degumming, insoluble sericin ratio on degumming solution was increased by increasing treatment temperature at Ca(OH)$_2$ 0.04% solution. At the concentration Ca(OH)$_2$ of 0.07%, a soluble ratio was almost 100% regardless of treatment time and temperature. At the beginning of treatment, insoluble ratio was high at Ca(OH)$_2$ 0.1% solution but it was decreased by increasing treatment time. At the Ca(OH)$_2$ concentration of 0.04%, D.P. of soluble sericin was maintained as a constant value of 10 at 100$^{\circ}C$ although treatment time was increased. However, at 80$^{\circ}C$ and 90$^{\circ}C$, it was hard to prepare a soluble sericin having a constant D.P. by increasing treatment time. At the Ca(OH)$_2$ concentration of 0.07%, D.P. was almost 10 irrespective of treatment temperature and time. Soluble sericins with high D.P. of 20∼30 were obtained at 0.1% and 100$^{\circ}C$. LAL was not detected in soluble sericin. As the results of amino acid analysis, it showed that Ca(OH)$_2$ degumming reduced the contents of hydroxy amino acids like Ser., Thr. and Tyr. In DSC analysis of soluble sericin, endothermic peak by thermal deformation and pyrolysis showed at 189$^{\circ}C$ and at 299$^{\circ}C$, respectively. The tenacities of degummed silk were 15∼30% lower than that of raw silk. And it was decreased with increasing treatment time. From the morphological study, the thickness of degummed silk fibroin became thinner by increasing degumming loss. The roughness of a silk fibroin surface was appeared as treatment concentration was increased.

• 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 East Asian Society of Dietary Life
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• v.20 no.3
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• pp.396-401
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• 2010

The purpose of this study was the development of adsorbents for the refining of edible oil using agricultural byproducts such as rice hull, barley hull, and soybean hull as well as evaluation of their adsorptive effects against free fatty acids and lutein, the major impurities of soybean oil. Ash-type and carbon-type adsorbents were produced from the hulls. Ash-type adsorbents such as rice hull ash (RHA), barley hull ash (BHA) and soybean hull ash (SHA) were effective for the removal of free fatty acids; the acid value of degummed soybean oil was decreased by 86% upon treatment with 5% SHA. However, carbon-type adsorbents such as rice hull carbon (RHC), barley hull carbon (BHC), and soybean hull carbon (SHC) were effective for removing lutein, resulting in a 52% decrease in the lutein content of degummed soybean oil upon treatment with 5% SHC. Whereas ash-type adsorbents were composed of mesopores or macropores with small surface areas and total pore volume, carbon-type adsorbents were mainly composed of micropores with large surface areas and total pore volume.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.425-430
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• 1995

The effects of oxidation stability and flavor acceptability of soybean oil by roasting and refining treatment were investigated in this study. The peroxide values of crude oil from unroasted soybean(COUS) were more increased than those of crude oil from unroasted soybean(CORS) during storage under fluorescence light at $45^{\circ}C$. Induction time by the Rancimat Method was 44.9 and above 88.7 hours on COUS and CORS respectively. The order of oxidation stability of oil was crude>degummed>alkali-refining>deodorized>bleached oil in terms of peroxide value, while that of oxidation stability of oil was crude>degummed>deodorized>alkali-refining>bleached oil in regard to induction time by the Rancimat Method. The correlation coefficients between induction time and two charateristics(absorbance of browning reaction products and phosphorous contents) were highly significant, while that between induction time and tocopherol contents was not high during refining stages. The scores for the sensory evaluation of flavor on sesame oil and CORS was 9.269 and 8.269 respectively, but it was not significant between two oils.