• International Journal of Industrial Entomology and Biomaterials
• /
• v.45 no.2
• /
• pp.78-83
• /
• 2022

There are several subspecies of Bombyx mori, whose silk sericin variants differ. Silk sericin can induce bone morphogenic protein-2 (BMP-2) in macrophages, and silk sericin from different species may have different levels of BMP-2 induction ability. In this study, silk sericin from three B. mori subspecies (Baegokjam, Yeonnokjam, and Goldensilk) was prepared. They were administered to RAW264.7 cells and BMP-2 expression level was studied. Bone regeneration was evaluated using a rat calvarial defect model. BMP-2 expression level was the highest in the Baegokjam group. The bone volume in the Baegokjam group was significantly higher than that in the Yeonnokjam group (P = 0.003). In conclusion, sericin from Baegokjam showed higher levels of BMP-2 expression and bone regeneration than those from Yeonnokjam and Goldensilk.

• Journal of Sericultural and Entomological Science
• /
• v.43 no.1
• /
• pp.41-48
• /
• 2001

The purification, dissolution and powdering of stained waste silk obtained from weaving and dyeing process were studied for the surface modification of textile fabric and plastic materials. The whiteness of stained waste silk could be improved through degumming and bleaching with sodium hydrosulfite. The water-soluble fibroin solution can be obtained by dissoving the degummed waste silk in a boiling solution of 50% calcium chloride for 60 minutes. The salts and heavy metals contained in fibroin solution were removed by electric dialysis, wool fiber filtration and gel filtration chromatography. The fibroin powder was prepared by using a fine grinder after the alkali treatment for weakening the silk fiber. The fine fibroin powder of particle size around 30 ㎛ was obtained with a ultra fine-mill, while it was finer below 10 ㎛ with a ball-mill. The dissolved or powdered silk was applied to the surface of fabric with addition of the binder (a urethane resin). The moisture content of polyester and nylon fabrics treated with the silk solution was improved due to hygroscopic property of silk. The fine fibroin powder mixed with the binder ws coated on the surface of synthetic film by use of the air pressed sprayer. It was revealed that the hygroscopicity as well as the softness of fibroin powder coated film was much improved. Therefore, it is thought that the fine silk fibroin powder is applicable as an coating agent for the surface modification of plastic and synthetic leather.

• Applied Biological Chemistry
• /
• v.12
• /
• pp.75-81
• /
• 1969

In order to obtain a method of scouring of raw silk and degumming of cocoon by the appling of bacterial enzyme of sericinase, a strain of proper bacteria was isolated and some properties of the enzyme produced by the isolated bacteria were studied and the following results were obtained. 1) Optimum pH and temperature were indicating 7.5 and $50^{\circ}C$. and on these conditions, the silk fibroin will get no modification at all. 2) Sericinase activity was inhibited by calcium ion in the free incubation but same ions reacted as an activator in the reaction with substrate. So, degumming of Tussah cocoon which contains calcium oxalate in the cocoon layer will be possible by the treatment of this enzyme. 3) This bacterial sericinase never gives any affection to the fibroin layer of the silk. 4) The factors of smooth-surface condition, damage of fibroin layer, touching, luster and degumming effect of the silk resulting by the enzyme treatment were more appropriate than the results of other scouring methods, saponin, alkali and saponin-alkali using methods. We expect to get the same scouring result that compared with the papain or pancreatin were applied.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.19 no.2
• /
• pp.265-268
• /
• 2009

Wild silkmoths can be utilised sustainably in the production of silk as an income for resource-poor rural communities. However, attack by parasitoids and predators affect the quality of cocoons and quantity of raw silk produced. A laboratory experiment was undertaken to quantify the effect of parasitoids' (dipteran and hymenopteran) and predators' (ants) exit and ingress holes, respectively, on silk production. The mean number of shells required to produce fifty grams of raw silk was highest with cocoons parasitised by a dipteran and lowest with unattacked cocoons (but with moths already emerged). Degumming loss was highest in parasitised and lowest in unttacked cocoons, but both were not different from cocoons predated by ants. Shell weight was highest in unattacked cocoons, followed by hymenopteran-parasitised and predated cocoons, with the dipteran parasitized ones being the least. Single cocoon weight was greater in hymenopteran-parasitised and predated cocoons than the dipteran-parasitised and unattacked cocoons. Shell ratio or raw silk, floss and yarn weights were higher in unattacked than parasitised and predated cocoons. The total loss in raw silk attributable to attack by parasitoids and predators ranged between 17.4~31.2%. The results offer baseline information for assessment of economic losses in wild silk farming due to parasitoids and predators in the field.

• Proceedings of the Korean Society of Dyers and Finishers Conference
• /
• 2007.11a
• /
• pp.45-46
• /
• 2007

• International Journal of Industrial Entomology and Biomaterials
• /
• v.27 no.1
• /
• pp.203-208
• /
• 2013

Sericin is usually abandoned after the degumming process. However, it could be a valuable bioresource if an economically efficient recovery process could be set up. In this study, sericin was recovered directly from the degummed waste solution by adding calcium chloride, which induced the precipitation of the surfactant, sodium oleate, by charge interaction. The recovery yield was maximum when 10% of calcium chloride was added. Further increase in the calcium chloride concentration induced the precipitation of sericin. The recovered sericin had a molecular weight distribution similar to that of the hot-water-extracted sericin; but some highmolecular- weight sericin could not be recovered. The secondary structure and amino acid composition of the recovered sericin were similar to those of conventional hot-water-extracted sericin. We expect that sericin recovered from the degummed waste solution could be an alternative to the hot-water-extracted sericin, which is widely used in various applications.

• Journal of Sericultural and Entomological Science
• /
• v.40 no.2
• /
• pp.150-157
• /
• 1998

This study was carried out to define the effects of anti-juvenile hormone analogue(AJH) treatment at different silkworm larval stages on some silk filament properties. It was revealed that the treatments at the 1st and 2nd days of the 3rd instar as well as the 1st day of the 4th instar resulted to trimolters induction without lethal effect. The trimolters induced by treatment at the 1st day of the 4th instar showed the shortest larval duration and the lowest single cocoon weight, cocoon shell ratio, cocoon size, single filament length and denier of filament compared with those of the control, while the trimolters induced by the 3rd-instar treatment showed intermediate values. All treatments showed no significant differences from the aspect fo degumming ratio, elongation rate and crystallinity index of fibroin. However the silk filament obtained from the treatment at the 1st day of the 4th instar showed the highest tenacity which was revealed to be related to the better uniformity of filament by the means of microscopic photographing. FT-IR spectroscopy of the silk fibroin showed a sharp and strong peak at the position of 794.72 cm-1 in all AJH-treated samples regardless of trimolters induction, which was absent in control.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.34 no.5
• /
• pp.754-764
• /
• 2010

Most silk fabrics are produced only after the degumming process to make the best use of the properties and have restricted silk processing that do not hinder their performance. However, considering the highly increased preference for natural fibers and the shortage of raw silk, high-quality upgraded silk product functions are required by the development of a processing technology and a good design. This study analyzes the changes with the samples by the functional finish such as softening finishing, wash and wear, tannin weighting by measuring the objective hand of scoured silk and three finished ones using KES-FB. As a result, the change of objective hand of finished silk fabrics that improves functionality was analyzed and compared. The increase of KOSHI after the finish became stiffer show that the silk fabric samples are appropriate for summertime clothes with the retention of a certain clothing climate for the body. The stiffness of finished fabrics for the normal had a closer relationship with the density of fabrics than the type of finishing. The samples (after the softening finishes) maintain better elasticity according to the properties of the softener and the finishing agent. Although the specimens of this study were thin fabrics, their elasticity against compression increased after the softening finishes and became softer than degummed silk. The surface properties of georgette were changed by all types of finishing.

• Journal of Sericultural and Entomological Science
• /
• v.29 no.2
• /
• pp.67-72
• /
• 1987

This study was carried out for the optimum predegumming in the protease degumming process of silk fabrics by ocmparing the physical properties of silk fabrics degummed with different weight losses of predegumming. 1. In twill habutai, the stiffness of fabric was reduced and the smoothness was improved with increasing weight loss of predegmming, however, the soft feeling value which means the total handle value of medium fabric for lady, was maximum at 20% of predegumming weight loss. 2. In the case of crepe de chine representing thin fabric for lady, the anti-drape stiffness was relatively increased with 22% weight loss of predegumming. However, the other physical properties, such as the flexibility with soft feeling were less related to the degrees of predegumming.

• Proceedings of the Korean Fiber Society Conference
• /
• 2003.04a
• /
• pp.275-278
• /
• 2003

실크 세리신은 누에(Bombyx mori)로부터 얻어지는 천연 거대분자 단백질로서, 누에고치실의 20~30%를 차지하고 있다. 세리신은 외부로의 자극으로부터 피브로인을 보호하는 역할을 하지만, 견사나 견직물을 얻기 위해서는 정련 공정에서 반드시 제거하게 된다. 현재 생산 현장에서는 비누/알칼리 정련법으로 세리신을 제거하고 있는데, 정련 폐액중에 포함되어 있는 세리신 단백질에서 분해된 각종 아미노산과 비누 및 강알칼리 약제로 인해 환경오염의 주된 원인이 되고 있다. (중략)