• International Journal of Industrial Entomology and Biomaterials
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• v.41 no.1
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• pp.1-5
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• 2020

Tumor necrosis factor-α (TNFα) is a representative marker for inflammation. Silk sericin is known as mild TNFα inducer. The purpose of this study was to compare the level of TNFα among different fractions of silk sericin. Silk sericin was extracted from cocoon and separated it by molecular weight. Each fraction was applied to RAW264.7 cells. The level of TNFα was evaluated by western blot and ELISA assay. In results, the level of TNFα was increased as time-dependent manner. Higher molecular weight fraction of sericin induced higher amount of TNFα than lower molecular weight fraction. In conclusion, different molecular weight fraction of sericin induced TNFα differently.

• Journal of Sericultural and Entomological Science
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• v.7
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• pp.75-79
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• 1967

The aim of this treatise was to investigate the effects of ultra-red ray on the ree1ability of the undried and dried cocoons as well as the characteristics of raw silk. The results obtained are as follows: 1. The percentage of raw silk of undried cocoons was higher than that of dried cocoon and control. 2. On irradiation with ultra-red ray, it was found that the strength of raw silk increased to 4.5 g/d, while the elongation of it remarkably decreased. 3. The raw silk irradiated with ultra-red ray appeared to be brown in color.

• Journal of Sericultural and Entomological Science
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• v.39 no.1
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• pp.56-61
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• 1997

The silk fibroin solution was prepared and applied to the surface of fabrics for the purpose of weighting as well as a surface modification. The water-soluble fibroin solution can be obtained by dissolving the cocoon fibroin in a boiling solution of 50% calcium chloride for 60 minutes. For the fixation of a water soluble fibroin onto the fabric surface, the various methods were investigated. The fixation can be achieved on a silk fabric by the after treatment with ethanol, stannous choride and methacrylamide. On the other hand, the epichlorhydrin compound is the most promising fixation agent for a cotton fabric. As a result of the examination of property changes, the softness and crease recovery were lessened for a silk crepe fabric by treating with 1-2% fibroin solution, while those properties were improved for a silk knit fabric.

• International Journal of Industrial Entomology and Biomaterials
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• v.22 no.1
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• pp.1-4
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• 2011

This study was conducted to test the use of colored cocoon silkworm, Golden Silk, as a host for the fruiting body production of Cordyceps mushroom. Golden Silk variety had a shorter larval period than Yangwonjam at $25.3^{\circ}C$ and 78.5% RH: The average larval period of the Golden Silk was 24 days and 7 hr, and that of the Yangwonjam was 24 days and 15 hr. In the infection test of I. tenuipes on silkworm, the larval period of normal silkworms was longer than the silkworms inoculated with I. tenuipes in both Golden Silk and Yangwonjam. The pupae survival percentage of Golden Silk was 94.4%, whereas it was 91.9% in Yangwonjam. Golden Silk had a higher pupation rate than Yangwonjam. The pupation rate of normal silkworms was about 5% higher than that of silkworms inoculated with I. tenuipes. Infection rate of I. tenuipes into larvae of 5th instar newly exuviated silkworm was 93.8% in Golden Silk, and 96.9% in Yangwonjam. Synnemata production of I. tenuipes was better in Yangwonjam with an incidence rate of 99.8% than Golden Silk with 98.6%. The average synnemata weight of Golden Silk was 1.12 g and that of Yangwonjam 1.29 g. Golden Silk had a lower synnemata weight than Yangwonjam. But no significant difference was observed in synnemata weight varieties. The synnemata of I. tenuipes produced on pupae were white or milky-white in color, and similar in shape and color to wild synnemata collected in Korea.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.171-178
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• 2003

Four thermo-tolerant lines of silkworm, Bombyx mori, (L.) viz., A HT, B HT (Chinese type) and F HT, G HT (Japanese type) were evolved by utilizing the breeding resource material (identified from initial screening at a temperature of 31 ${\pm} 1^{\circ}C$ and relative humidity 85 ${\pm}$ 5%) through conventional breeding. These tolerant lines were crossed with productive breeds and forty four hybrids were evaluated on eight economic traits by the Multiple Trait Evaluation Index Method. Ten hybrids were short-listed based on the average evaluation index value larger than 50 for eight economic traits studied. The identified ten hybrids recorded higher index values (＞ 50) for most of the traits studied. Single hybrid G ${\times}$ CSR12 indicated average index value larger than 50 for six traits viz., pupation number (58), cocoon weight (67), shell weight (65), average filament length (74), raw silk % (69), reelability % (51) except for shell ratio % (41). The standard deviation of the cocoons in the above hybrid was 8.41 in the hybrid cocoon length and width measurement. However, two selected hybrids viz., A ${\times}$ CSR5 and G ${\times}$ CSR13 recorded average index value larger than 50 for all the traits viz., pupation number (57, 60), cocoon weight (50, 54), shell weight (56, 57), shell ratio percentage (59, 53), average filament length (55, 60), raw silk percentage (63, 67) and reelability percentage (53, 53). The standard deviation of the cocoons in the two selected hybrids viz., A ${\times}$ CSR5 and G ${\times}$ CSR13 was 8.41 and 8.06 respectively in the cocoon length and width measurement.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.1
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• pp.79-83
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• 2002

The wild silkmoth, Actias gnoma was firstly collected at Suwon located in the middle part of Korea. The developmental and morphological characteristics of A. gnoma reared under the laboratory conditions were analysed. The egg shape was shorter elliptic. The major and minor diameter of the eggs were 2.04 mm and 1.83 mm, respectively. White mucous material was remained inside the eggs after hatching. Also, the body color of the larvae was completely changed from dark brown to light yellowish-green at the 3rd instar, but it did not occur until pupation. In the feeding test on several plants, the oak tree, Quercus acutissima, was newly identified as a host plant. The final larval instar was mostly 6th, but in some larvae it was 7th. A few of larvae ate their own casts just after ecdysis. The whole larval duration ranged from 45 to 59 days. The single cocoon weight, cocoon shell weight and cocoon shell percentage were 1.65 g,31.3 cg and 18.9%, respectively, The cocoon shape and color were spindle and light brown, respectively. The morphology of the silk gland was greatly different from those of Bombyx mori, Antheraea yamamai and Antheraea peryi: the thickness of the middle and posterior silk glands was almost identical.

• Journal of Sericultural and Entomological Science
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• v.36 no.1
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• pp.8-25
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• 1994

The study was conducted to obtain the genetic information on heterosis and combining ability of the quantitative characters for F1 hybrid breeding in silkworms. Six parental varieties and each set of 30 diallel crosses in F1's were used as materials, and bred on the randomized complete block design with three replications. Fourteen characters were observed with the twenty samples in each tray. The data were analyzed for (1) heterosis and combining ability in F1 hybrid. The heterosis in the weight and the length of cocoon showed positively high at 24.51%, and 23.4%, respectively and the weight of the whole cocoon as well as the weight of the whole cocoon layer showed a siginificant heterosis ranging from 15.56% to 15.71% and from 17.14% to 19.01%, but the fifth and the total instar period showed negative heterosis. It was found that the combination between, C70XRomogua and N9 X Romogua showed highly a negative heterosis on the fifth instar period and for the cocoon weight. The female of N9+Sansuian and the male of Romogua X Sansurian have a high heterosis effect, on the cocoon shell weight, and Sansurian X Romogua(reciprocal) on the length and the weight of cocoon filament with no regard to sexuality. The significant maternal and cytoplasmic effect on heterosis of the cocoon weight and the cocoon shell weight were observed with the combinations, N9 X C5, N63 X C70 and on the length of the cocoon filament with the combinations, Sansurian X N63, Sansurian X C5, Sansurian X C70 and N9 X C70, N63 X C70 on the weight of cocoon filament. As mean squared of GCA, SCA and RCA were significant with these combining ability for all characters resulted from additive and non-additive altogether and there is a significant difference between reciprocals. Sansurian showed a negative GCA effect on the fifth and total larval duration, but the higher positive GCA effects took places with varieties N9 and C5 on the length, width, weight of cocoon, cocoon shell weight, percentage of cocoon shell weight, length and weight of cocoon filament, percentage of raw-silk with no regard to both generations and silkworm sexuality. The values of SCA between the cross combinations varied generation-wise and sex-wise. It was shown that SCA value for the fifth instar period was highly negative for Sansurian X C70, Romogua X C70, Sansurian X C5, Romogua X C5, but it was positive effect on the cocoon weight, cocoon shell weight with N9 X C5, and C70 X Sansurian, on the length of cocoon filament with N9 X C5, Romogua X Sansurian on the weight of cocoon filament between Romogua and N63 and on the percentage of raw-silk between the combination of Sansurian X Romoga.

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

• Current Research on Agriculture and Life Sciences
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• v.1
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• pp.55-65
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• 1983

The purpose of this study is to find out influences of several chemicals on the solubility of cocoon sericin in water, and there are several results of use to control the solubility of cocoon sericin in water. The results obtained are summarized as follows : The chemical which shows the strongest accelerating power of the solubility of cocoon sericin in water is Sodium Hydroxide (NaOH), the second is Potassium Hydroxide (KOH), the third is Sodium Silicate ($Na_2SiO_3$), and the weakest is Sodium Bicarbonate ($NaHCO_3$) in order among noticed silk-reeling accelerators. The chemical which shows the strongest inhibiting power of the solubility of cocoon sericin in water is Form Aldehyde (HCHO), the second is Ammonium Alum ($Al_2(SO_4)_2{\cdot}(NH_4)_2SO_4{\cdot}24H_2O$), the third is Acetic Acid ($CH_3COOH$), the weakest is Hydrochloric Acid(HCl) in order among noticed silk-reeling inhibitors. Particulary Hydrochloric Acid (HCl), which is expected to show strong inhibiting power of the solubility of cocoon sericin in water, shows accelerating power of the solubility of cocoon sericin at high temperature over 80 degrees of Celsius thermometer in water.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.70-78
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• 1985

The purpose of this study was to find out effects of several chemicals treatment for cocoon sericin. and there was several results of use to control the solubility of cocoon sericin in water. The results obtained was summarized as follows ; The chemicals which showed the strongest accelerating power on the solubility of cocoon sericin in water was sodium peroxide ($Na_2O_2$), the second was sodium carbonate ($Na_2CO_3$), the third was sodium sulfite ($Na_2SO_3$), the weakest was ammonia water ($NH_4OH$) in order among noticed silk-reeling accelerators. The chemicals which showed the inhibiting power on the solubility of cocoon sericin in water was tannic acid ($C_{14}H_{10}O_9$), the second was stannic acid ($Sn(OH)_4$), the third was formic acid (HCOOH) and the weakest was methyl alcohol ($CH_3OH$) in order among noticed silk-reeling inhibitors. Particulary stannic acid and formic acid showed accelerating power on the solubility of cocoon sericin at high temperature over 100 degrees of celsius thermometer in water Methyl alcohol did not show the inhibiting power on the solubility of cocoon sericin in low concentration. (at 1,500-2,000 times)