• International Journal of Industrial Entomology and Biomaterials
• /
• v.3 no.2
• /
• pp.169-175
• /
• 2001

A synthetic juvenoid, R394 (Ethyl 9-cyclohexyl-3, 7-dimethyl-2, 4-nonadienoate) which is known to be a strong pest control agent was administered to silkworm, Bombyx mori L. in minute quantity for improving the silk yield. Based on the result of an earlier preliminary screening, three concentrations of the compound, viz., 0.1563, 0.3125, 31.25 nl/ml were prepared in the form of an emulsion and administered topically as a single dose, to separate batches of $5^{th}$ instar silkworm at 24, 48, 72 and 96 hrs to determine the required concentration and critical time of application for an economically favourable response. Two popular commercial silkworm hybrids, PM ${\times}$ NB4D2 (multivoltine${\times}$bivoltine) and KA${\times}$NB4D2 (bivoltine$\times$bivoltine) were subjected to the experiment. The medium and absolute control were maintained in parallel to compare the results. The results showed that 0.3125 nl/ml was the best concentration of the compound and 72 hrs of $5^{th}$instar was the most favourable age for its administration to get the maximum improvement in the commercial traits. The possible role of exogenous juvenoids in eliciting favourable response in silkworm which ultimately leads to improvement in the commercial traits is discussed.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.14 no.2
• /
• pp.81-85
• /
• 2007

White Muscardine is the most common fungal disease of silkworm, Bombyx mori L. caused by the pathogenic fungus, Beauveria bassiana (Balsamo) Vuillemin. In the present investigation, an attempt has been made to screen locally available medicinal/ weed plants against Beauveria bassiana. Among the plant extracts (PE) tested, 5% aqueous crude extract of the bulb of Allium sativum (Garlic) has been found to be most effective against Beauveria bassiana. The radial growth of Beauveria bassiana in vitro was inhibited to the tune of 54.9% in aqueous extract and 54.4% in ethanolic extract of Allium sativum and correspondingly mycelial dry weight gave rise to 110.7 mg and 108.7 mg against 201.7 mg in control 15 days post treatment. Similarly, silkworm larvae topically inoculated with the Beauveria bassiana conidia ($1.8{\times}10^6/ml$) registered survival up to 53.0% against 0.0% in control after treatment with aqueous extract of Allium sativum. Simultaneously, as a preventive measure, silkworm larvae were put to rear in conidia contaminated seat paper instantly treated with aqueous extract of Allium sativum that also increased survival up to 61.0% against 4.6% in control. It is also observed that the plant extract is absolutely innocuous to silkworm.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.45 no.1
• /
• pp.1-11
• /
• 2022

Silkworm pupae, a by-product of the silk industry are known to be valuable resource of nutrients for humans as well as animals besides encompassing diverse bioactive constituents. However, there is a paucity of knowledge on their role in amelioration of oxidative stress and anti-skin aging properties. In the present study, we evaluated the inhibitory effect of aqueous as well as ethanolic (30% and 70%) extracts from distinct stages of male and female silkworm pupae belonging to two silkworm varieties on skin aging-related enzymes. The activities of collagenase, elastase and tyrosinase were effectively inhibited by 70% ethanolic silkworm pupal extracts (SPE), followed by 30% with aqueous extracts exhibiting meager inhibitory potential. SPE were also investigated for their antioxidant activity in oxidative-stressed murine fibroblasts (L929). The intracellular ROS and lipid peroxidation induced by tert-butyl hydroperoxide (t-BHP) in fibroblasts was better attenuated by pre treatment with ethanolic (30%) and aqueous extracts, respectively. The safety of the extracts was determined by studying their effect on fibroblast cell viability and it was found that none of the extracts were cytotoxic. Our findings indicate the potential utility of SPE as anti-aging components in cosmeceuticals.

• Journal of Sericultural and Entomological Science
• /
• v.51 no.1
• /
• pp.73-77
• /
• 2013

Silkworm transgenesis scientists have done some genetic modification work on multivoltine silkworms, but that type of silkworms is less commercial feasible. They are easy to manipulate, because they breed all year round. But the commercial silkworm variety must undergo hydrochloric acid treatment at a high temperature to be artificially hatched. Hydrochloric acid penetrates through the holes in the silkworm eggs, fatally damaging their reproduction. So it had been thought that altering the properties of the commercial silkworm variety would be very difficult. So we have tried to make from diapause to non-diapause eggs using diapauses varieties, 'Backokjam' and 'Jam 124'. At present, our group has establishing the conditions for non-diapause eggs. Oviposited eggs after 40 ~ 60 hours were incubated for 24 hours at $15{\sim}20^{\circ}C$ with dark condition. Non-diapause eggs were completely induced. The hatching rate, molting rate and pupation rate of non-diapause 'Jam 124' and 'Backokjam' eggs showed no differences compared to diapause eggs. When transgenic silkworm using the non-diapause eggs, the hatching rate showed that non-diapause eggs induced from diapause were 40 ~ 70%, diapause eggs treated with artificial incubation were 10 ~ 30%, and polyvoltine strains, HM eggs were 30 ~ 50%. Therefore, we suggest that modification techniques of the commercial silkworm eggs adequate for silkworm transgenesis can be used to develop transgenic silkworms more easily.

• Food Science of Animal Resources
• /
• v.28 no.5
• /
• pp.521-528
• /
• 2008

This study was performed to evaluate the quality change of pork patties containing silkworm powder and vegetable worm (Paecilomycis japonica) stored for 9 days at $5^{\circ}C$. pH values were higher in treatment groups than that in controls by storage day 6. L (lightness) and a (redness) value were decreased with increasing addition of silkworm powder and vegetable worm powder in pork patties (p<0.05). However, b value (yellowness) was increased with increasing addition amounts of the silkworm powder and the vegetable worm powder (p<0.05). Water holding capacity (WHC) of pork patties was not affected by the silkworm powder and the vegetable worm powder, while pork patties containing 0.4% silkworm powder (T2) showed low cooking loss (p<0.05). Pork patties containing either silkworm powder and vegetable worm alone or a combination of them showed lower lipid oxidation value than that of control (p<0.05). Sensory preference of pork patties was decreased with increased of storage days. The overall acceptance was higher in treatment groups than at control groups at the initial day (p<0.05), yet no significant difference was found during storage. From these results, 0.4% silkworm powder decreased not only cooking loss but also lipid oxidation of pork patties. Also, no adverse effect was found in water holding capacity (WHC) and sensory preference of pork patties. Therefore, the silkworm powder and the vegetable worm powder could be useful to pork meat product industry as additives.

• The Korea Journal of Herbology
• /
• v.32 no.4
• /
• pp.1-8
• /
• 2017

Objectives : Silkworm is known as immunomodulatory substances and contain various bioactive compounds such as serine, tyrosine and alanine. The aim of this study was to investigated the immunopotentiating activity of combine extract that silkworm and food materials (Eucommia ulmoides, Angelica gigas, Acanthopanax, Allium hookeri, Cinnamomum cassia, Liriope platyphylla, Curcuma longa, Achyranthes japonica, Alpinia oxyphylla, Adenophora triphylla). Methods : Among 10 kinds of food materials, to select food materials with the effect of enhancing the immune function mouse splenocyte proliferation ability was measured by 3-[4,5-dimethylthiazol-2-y]-2,5-diphenyl terazolium bromide (MTT) assay. Then, combine extract of silkworm and food materials were evaluated that mouse splenocyte proliferation ability by EZ-cytox cell viability assay. Morever, cytokines production such as IL-2, IL-4, IL10, IL12, $IFN-{\gamma}$ on mouse T lymphocyte stimulated with concanavalin A (ConA) was measured. Results : Eucommia ulmoides, Acanthopanax, Allium hookeri, Cinnamomum cassia, Liriope platyphylla has high proliferation ability of mouse splenocyte compared with Curcuma longa, Achyranthes japonica, Alpinia oxyphylla, Adenophora triphylla. The silkworm and food material combined extract has a relatively high proliferation ability of mouse splenocyte proliferation when the silkworm and food materials are used as a single material. In particularly, combined extract of silkworm and Cinnamomum cassia was stimulate cytokine production on T lymphocyte such as IL12, $IFN-{\gamma}$. Combined extract of silkworm and Liriope platyphylla was stimulate cytokine production on T lymphocyte such as IL2, IL4, IL10. Conclusion : In conclusion, the combined extract of the silkworm and Cinnamomum cassia or Liriope platyphylla may enhance immune function by regulating mouse splenocyte proliferation and stimulating cytokine production.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.5 no.2
• /
• pp.195-199
• /
• 2002

In order to find potential anticancer agents, we extracted pheophytin in the silkworm feces from various larval stages by water, chloroform and methanol extraction. The cytotoxicity of the pheophytin extracts of various silkworm feces was measured in the CT-26 cells originated from murine metastatic colon cancer, by dye uptake assay. The cytotoxicity of those pheophytins in 2nd, 3rd and 4th instars was better than remaining larval stages. The in vitro anticoagulant and fibyinolytic activities of ethanol extract from varietal mulberry leaves, mulberry branches and silkworm feces and pheophytin extracts from silkworm feces obtained at various larval stages were evaluated in order to find effective therapeutic drugs for the treatment of myocardial and cerebral thrombosis. The fibrinolytic activity was tested using the activated partial thromboplastin time (APTT) and thrombin time (TT) was measured for blood clotting activity. With regards to the fibrinolytic system, ethanol extracts of silkworm feces were better than varietal mulberry leaves and mulberry branches. The pheophytin extracts from 7th days of 5th instar contained the highest percentage of pheophytin and good fibrinolytic activity.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.14 no.1
• /
• pp.15-21
• /
• 2007

Three newly authorized bivoltine silkworm hybrids namely, $CSR2{\times}CSR4$ (productive single hybrid), $(CSR6{\times}CSR26){\times}(CSR2{\times}CSR27)$ (productive double hybrid) and $CSR18{\times}CSR19$ (robust single hybrid) were chosen for the present study. These hybrids were subjected to different temperature and humidity treatments i.e., $25{\pm}$1^{\circ}C and RH $65{\pm}5%$ (control), $30{\pm}1^{\circ}C$, with combinations of low relative humidity (RH $65{\pm}5%$) and high RH ($85{\pm}5%$) at different stages during rearing and spinning of silkworm larvae. The larvae of after 3rd moult were subjected to different thermal and humidity stress till the assessment of cocoon traits. The comparative rearing and reeling performance clearly indicated that the deleterious effect of high temperature and high RH was more pronounced for the majority of traits such as cocoon uniformity, cocoon weight, shell weight, shell percentage, reelability, filament length, raw silk percentage raw silk recovery denier and waste percentage on silk weight than other temperature and RH treatments and this effect was almost similar for all three silkworm hybrids studied. The present investigation clearly indicate that the deleterious effect of high temperature and high RH was more pronounced on rearing and spinning of silkworm larvae than other temperature and RH treatments and similar effect was noticed for all the three silkworm hybrids studied. The cocoon characters can be improved by providing ideal environmental conditions even during spinning stage of larvae affected with high temperature and RH. The study also suggest that high temperature and low humidity has greater effect during rearing stage than spinning stage.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.24 no.2
• /
• pp.69-74
• /
• 2012

Tropical tasar silkworm Antheraea mylitta Drury experiences extreme temperature stress conditions during its life cycle particularly during diapauses and first crop. The present study witnessed the impact of high temperature on some biochemical profiles and egg production (fecundity) of semi-domesticated Daba and Shorea robusta (Sal) based wild ecorace Laria during seed cocoon (pupa) preservation. Cocoons of Daba and Laria were treated with high temperature at $40^{\circ}C$ for 10 days in a BOD incubator. The protein profile and carbohydrate content in the hemolymph and fat body and total haemocyte count (THC) in the hemolymph of pupa were investigated. Further, the fecundity and fertility of egg was assessed. Significant increase in the protein concentration was observed in the hemolymph with reduction in the fat body (p<0.05). The difference in protein concentration was highly significant between the semidomesticated Daba and wild ecorace Laria (p<0.05). High pupal mortality (20%) and reduced fecundity (10-15%) in Daba was noticed compared to wild Laria. Also an increased THC (>28000) was recorded in Laria. The study infers the potentials of wild ecoraces in sustaining the extreme temperature conditions and need of adopting suitable package of practices for the preservation of diapause seed cocoons during extreme summer conditions. There is possibility to introgression thermal stress resistant traits in the semi-domesticated races of tasar silkworm by resorting to conventional breeding plans with wild races and keeping the thermal stress induced response as markers.

• Journal of Sericultural and Entomological Science
• /
• v.18 no.2
• /
• pp.101-105
• /
• 1976

The study was carried out to investigate the variations in the fibroin hydrolysis of leading silkworm varieties in Korea, and the relationship between the fibroin hydrolysis of the silkworm varieties with some characteristics and silk morphological property. The results obtained are summarized as follows: 1) The fibroin hydrolyzing ratio of both parent silkworm cocoons was reduced in the F$_1$hybrids. 2) A positive corelation (r=＋0.86) was approved between the mid-parent value and the F$_1$hybrid in the fibroin hydrolysis. 3) It was disclosed that the fibroin hydrolyzing ratio of Jam 103${\times}$Jam 104 was the lowest among the leading silkworm F$_1$hybrids. 4) The fibroin hydrolysis was affected by the silk morphological property, showing a positive corelation between the size of cocoon filament and the fibroin hydrolyzing ratio. 5) It was thought that the determination of the fibroin hydrolyzing ratio was useful as a marker for the selection of its related economical characters in silkworm breeding, because the fibroin hydrolysis of parents silkworm cocoons was heritable in their F$_1$hybrids.