• Journal of Sericultural and Entomological Science
• /
• v.17 no.2
• /
• pp.133-139
• /
• 1975

For developing the therapeutic agents to be administered orally for treating certain silkworm diseases and applying them to clinical conditions, vehicles suitable for the agents are needed. The author presumed that Lactose, Casein, and Urea, respectively, have an effectiveness as the vehicle. A series of experiments were carried out on these substances for conforming the applicability of the vehicles at the silkworm rearing house of the College of Agriculture, at Seoul National University during the spring silkworm rearing season of 1974 and the spring and autumn seasons of 1975. The author recognized, Lactose, Casein, and Urea, when put on the mulberry leaves in a powdered form, are eaten along with the leaves by silkworm. Thus, the systemic administration of them to silkworms are possible. The author administered these individual substances orally to silkworm larvae in doses of l0mg., 30mg., 50mg., and 100mg. per gram of the body weight of the silkworm larvae at intervals of once a day, once every two days, and once every three days for 15 days. This was carried out from the first day of the fourth instar to just before mounting. The influences of these substances on the growth of silkworm larvae and the cocoons made by the larvae were observed. The author found out after completing the experiment that Lactose had no effect on growth and cocoon formation. This was observed in all cases. Casein inhibited the growth of silkworms except in the case of administered doses of once every third day in whick the growth and the cocoons were normal but the administration of the agent brought considerably large numbers of abnormal cocoons in every case. Urea inhibited both the growth and the formation of tile cocoons in most cases. For the confirmation of the clinical effectiveness as the vehicles for some therapeutic agents, the three substances, Lactose, Casein, and Urea, will be investigated more closely for the mixing amounts needed and other pertinent data.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.8 no.1
• /
• pp.81-87
• /
• 2004

In order to investigate the effects of supplementary nutrients on silkworms, Bombyx mori, an experiment was conducted with ascorbic acid treatments. Dietary supplements of ascorbic acid 1, 2 and 3% were fed to silkworm larvae through 1st to 5th instar, The larvae were fed by mulberry loaves of Kokoso variety and the supplementary loaves were used once a day. These treatments resulted in a significant increase of biological parameters such as larval weight, the rate of food consumption and the approximate digestibility of the food. But the economical parameters such as cocoon weight and cocoon shell weight didnt show considerable difference compared to control. Dietary supplement of 2% ascorbic acid increased the larval weight by 7.8% and reached to 1.065g, which had the highest weight increase in the fourth day of 4th instar larvae. The percentage of daily weight increase in this group of larvae (79.01%) had significant difference compared with other treatments. The nutritional efficiency index in this group of larvae was better than others. Also the abundance of biochemical macromolecules such as glucose, cholesterol, triacylglycerol and urea in haemolymph of larvae fed by 2% ascorbic acid increased to become 29.75 (mg/㎗), 24 (mg/㎗), 75.4(mg/㎗) and 32.1(mg/㎗) respectively. But protein contents of haemolymph of larvae in each treatment were not significantly different. Since all the results achieved were not considerable either statistically or economically, this method could not be recommended to improve the sericultural parameters.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.7 no.1
• /
• pp.1-4
• /
• 2003

Sericulture is a traditional agro-industry, which involves mulberry cultivation and silkworm rearing, has made great contributes to the human civilization. With the development of national economy and modem technology, mulberry and silkworm are being used to develop products with functionality besides the traditional cocoon production in China. In this paper, we brief the current developing situation of sericultural byproducts with functionality in the following aspects. (1) Functional products from silkworm larvae: silkworm powder, white muscardine silkworm, isolation and purification of anti-bacterial proteins from the larvae and production of medically valuable substances by Bombyx mori nuclear polyhedrosis virus (BmNPV) vector. (2) Utilization of silkworm feces: for pillow and for isolation of chlorophyll etc. (3) Production of valuable Chinese traditional medicine like Cordyceps sinensis with pupae, functional utilization of pupa protein and chitin. (4) Silk as additives to cosmetics, silk food and medical materials. (5) Functional utilization of mulberry: cultivation of edible fungus on mulberry shoots as medium, mulberry fruit drinks, mulberry tea, etc. The prospect of sericultural byproduct industry in China is also 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.15 no.1
• /
• pp.9-16
• /
• 2007

The present study was aimed to screen different antibiotics in vivo for their effects against the bacterium Bacillus coagulans in silkworm Bombyx mori in three experimental conditions viz., a) healthy larvae treated with the antibiotics b) larvae which were first inoculated with Bacillus coagulans immediately after the $2^{nd}$ moult and treated with the antibiotics from 24 hour after inoculation up to the end of the $5^{th}$ instar(pre-inoculated larvae) and c) larvae which were treated with the antibiotics right from hatching up to the end of the $5^{th}$ instar and inoculated with Bacillus coagulans immediately after the $2^{nd}$ moult(post-inoculated larvae). All the antibiotics used in this study stimulated better performance in improving the rearing performance and economic characters of the cocoons in healthy, pre-inoculated and post-inoculated larvae, besides reducing the mortality of infected larvae. Cephelexin and Tetracycline were more effective than the others in their overall performance under all the three experimental conditions. Chloramphenical caused greater increase in the length of the reelable silk filament, but was not as good in elevating the other parameters compared to the remaining antibiotics. Of the four concentrations of antibiotics tested, 2.0% performed better under all the three experimental conditions.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.15 no.1
• /
• pp.35-38
• /
• 2007

In this study, ORF 46 of Bombyx mod nucleopolyhedrovirus(Bm46) fused with EGFP was expressed in Bombyx mod cell lines, larvae and pupae by BmNPV Bacmid system. Bm46 and EGFP were cloned into donor plasmid pFastBacHTb, which was transformed to competent DH10B cells containing helper and BmNPV bacmid by site-specific transposition. Recombinant bacmid was used to transfected BmN-4 cells to produce the recombinant baculovirus vBm-Bm46-EGFP. Recombination virus was injected into silkworm larvae and pupae. The expression of the fusion protein was monitored by examining green fluorescence using a fluorescent microscope. Intense fluorescence in cells and silkworm was observed at 4 days post-infection, indicating the Bm46-EGFP fusion gene was expressed successfully.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.18 no.2
• /
• pp.63-67
• /
• 2009

To increase utilities as functional materials, 173 strains of silkworm genetic resources in the form of silkworm powder were evaluated for antioxidative capacity, with minilum L-100 device and ARAW-KIT (anti-radical ability of water soluble substance). Silkworm powder was prepared with freezing method from silkworms at 5th instar 3rd day larvae. All strains of silkworm powder were prepared with 80% methanol extraction. The data of pupation rate, longevity of silkmoth with origin and voltinism were used for data base of silkworm genetic resources. The weight of a silkworm larva with freezing method at 5th instar 3rd day was measured. The average of antioxidative capacity of 173 silkworm strains was 429.68 nmol. The analysis of correlation among variables was significant, showing negative correlation of the antioxidative capacity with longevity of silk moth and weight of 5th instar silkworm larva. The strains from the tropic, Europe and some other origins were comparatively high. In conclusion, short longevity and low weight of 5th instar silkworm larvae showed comparatively effective antioxidative capacity.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.20 no.1
• /
• pp.13-17
• /
• 2010

Ten numbers of plants, based on their medicinal value, were used to test their efficacy against virosis (caused by cytoplassmic polyhedrosis virus) in tasar silkworm, Antheraea mylitta Drury. in indoor rearing conditions. The aqueous extracts of leaf of Azadirichita indica (neem), Acharanthus aspera, Psoralea corylifolia, Asparagus racemosus, Adhatoda zelanica (Basak), Andrographis paniculata (Kalmegh), Moringa oilephera (sahjan), whole plant of Phyllanthus urinaria (Bhuiamla), Centella asiatica (Veng sag) and Curcuma longa (Haldi powder) in different concentrations were used for containment of virosis in silkworm larvae. The tasar silkworm larvae were orally inoculated with PIBs ($1\times10^6$) of AmCPV in $2^{nd}$ instar and treated with plant extracts in each instar ($2^{rd}$ instar onwards). The mortality due to virosis was recorded during larval period. The plant extracts, irrespective of their concentrations, were found effective in suppressing the virosis where P. urinaria reduced the virosis to 56.90% followed by A. paniculata (53.82%) and least in C. asiatica (5.15%). The lowest pooled larva mortality 36.99% was recorded in the treatment of P. urinaria. Comparatively higher larva mortality 39.91% was observed with the treatment of A. paniculata. The highest larva mortality in treatment was with C. asiatica (81.99%). In treated control larva mortality was 86.50%.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.19 no.2
• /
• pp.221-228
• /
• 2009

Nosema sp. infection in the Indian tasar silkworm, Antheraea mylitta exerts a complex of influences on its host. The instar duration was extended significantly (P<0.001) except in $1^{st}$ instar. The infected larvae took about 48 days to reach the spinning stage against 40 days in the uninfected ones. The final weight attained by the larva at the end of each instar of development declined significantly following infection, as did weight gain and relative growth rate (RGR). The growth recorded/ day declined in infected larvae compared to uninfected ones from 8.2% during $1^{st}$ instar to 43.3% during $5^{th}$ instar. Food ingestion and digestion increased with advancement of the instar significantly irrespective of the status of the larvae but the relative consumption rate (RCR) declined. These parameters significantly declined in infected larvae (except food digested during $2^{nd}$ instar). The decline was more during $3^{rd}$ instar. In contrast, the approximate digestibility (AD %) was significantly higher in infected larvae than uninfected ones leaving the $1^{st}$ instar larvae unaffected. The efficiency of conversion of ingested food (ECI) and efficiency of conversion of digested food (ECD) did not change in a patterned way following the microsporidia (Nosema sp.) infection. The values of ECI significantly changed during $2^{nd}$, $3^{rd}$ and $5^{th}$ instars; while the change in ECD during $2^{nd}$, $4^{th}$ and $5^{th}$ were significant. During the entire larval life all the parameters tends to decline significantly following microsporidia infection but AD registered a significant increase. Nosema sp. spore concentration has increased 270.7 times during larval development in the course of experimentation.

• Journal of Microbiology and Biotechnology
• /
• v.14 no.3
• /
• pp.509-514
• /
• 2004

Six new serovarieties of B. thuringiensis carrying specific H-antigen have minor differences in biochemical characteristics and morphological characteristics of crystals, which are commonly resistant against four antibiotics. The B. thuringiensis serovar. coreanensis is nontoxic to silkworm larvae, but it is moderately toxic against the Culex pipiens larvae. The B. thuringiensis serovar. konkukian and leesis are nontoxic against mosquitos larvae, but are toxic against silkworm larvae. The B. thuringiensis serovar. seoulensis, sooncheon, and yosoo are highly toxic to B. mori larvae and moderately toxic to C. pipiens larvae. The six serovarieties harbor different plasmid DNA patterns. A 102-kDa protein is a major crystal protein in the four serovarieties and a 86-kDa protein is in one serovariety.