• International Journal of Industrial Entomology and Biomaterials
• /
• v.9 no.1
• /
• pp.107-109
• /
• 2004

The present investigation reports a phenomenon hitherto unknown in tropical sericulture, wherein dia-pause nature of bivoltine eggs is overcome through a cross with a non-diapausing race of silkworm, Bombyx mori, L. Eggs of bivoltine silkworm Bombyx mori, L. generally do not hatch under tropical conditions. To prevent diapause, they are subjected to acid treatment or low temperature hibernation scheduled. A race developed at KSSRDI is found to prevent the diapause nature of bivoltine eggs when crossed as male parent, without any acid treatment or hibernation schedule. This phenomenon is reported for the first time, being unique, opens up interesting area of research in silkworm genetics of commercial implications in the industry.

• Journal of Life Science
• /
• v.9 no.4
• /
• pp.341-347
• /
• 1999

Insects use chitinolytic enzyme to digest chitin in the exoskelton during the molting process. We have isolated and sequenced a chitinase-encoding cDNA from the silkworm, Bombyx mandarina, compared its sequenced with genes encoding chitinolytic enzymes from other sources. The insert DNA in the clone is 2,675 nucleotides long with an open reading frame of 1,695 uncletides that encodes a protein of 565 amino acids with a molecuar weight of 63.4 kDa. The 3' -untranslated region of 889 nucleotides is AT-rich and contains two putative polyadenylation signals. The N-terminal sequence of the encoded protein contains numerous hydrophobic residues characteristic of a leader peptide. The amino acid alignment revealed that the endo-$\beta$-N-acetylglucosaminidase had 83% and 97% homology with M. sexta and B. mori, respectively. The deduced amino acid had two highly conserved region at the amino acid residues 97-111 and 139-148 that were related to the existing chitinase.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.17 no.2
• /
• pp.189-195
• /
• 2008

The sequence of hydroxypyruvate isomerase gene was obtained in NCBI. In this study, the hydroxypyruvate isomerase gene of Bombyx.mori was identified and annotated with bioinformatics tools. The result was confirmed by RT-PCR, prokaryotic expression, mass spectrographic analysis and sub-cellular localization. The hydroxypyruvate isomerase cDNA comtains a 783bp ORF, and has 4 exons. The deduced protein has 260 amino acid residues with the predicted molecular weight of 29169.30 Da, isoelectric point of 6.10, and contains conserved PRK09997 and Hfi domains. The hydroxypyruvate isomerases of Nasonia vitripennis and Bombyx mori have a high homology. Through RTPCR analysis, we found that this transcript was present in testis, ovary, blood-lymph, fat body, midgut, silk gland and tuba Malpighii. This protein was located in cytoplasm through immunohistochemistry. We submitted the cloned gene under the accession number EU344910. The enzyme has been classified under accession number EC 5.3.1.22.

• Korean journal of applied entomology
• /
• v.31 no.1
• /
• pp.33-36
• /
• 1992

To establish the succeeding generations of wild silkworms, Bombyx mandarina Moore, massrearing was made in the laboratory. The rearing result was good under high humidity and moderately warm condition. Larval periods were 15 to 25 days and the most of larval period was around 17 days. The pupation rate and the pupal period of most of males and females were 40% and 13 to 25 days, respectively. There were two emergence peaks of males and females, and males emergence peak occurred two or three days faster than females.

• Korean Journal of Pharmacognosy
• /
• v.42 no.1
• /
• pp.68-75
• /
• 2011

A new lectin was purified from Bombyx mori (BML) by physiological saline extraction, ammonium sulfate precipitants, anion exchange column chromatography on DEAE Sephadex A-50 and gel filtration column chromatography on Sephadex G-200. BML agglutinated trypsinized and glutaraldehyde-fixed erythrocytes, and was observed the most high activity with rabbit, chicken erythrocytes and rat splenic lymphocytes. Agglutinability was markedly affected at highly acidic pH, but was relatively stable with high temperature. The effect of metal ions was observed and BML was affected by bivalaent cations, especially depending on $Ca^{2+}$, $Fe^{2+}$, $Mn^{2+}$, whereas, inhibited by $Mg^{2+}$. Agglutination was strongly inhibited by heparin and glucuronic acid. BML was proved to be a glycoprotein which contains 17.16% of sugars. By mass spectrometry analysis, we found 2 bands that were considered as lectin subunits.

• Journal of Sericultural and Entomological Science
• /
• v.42 no.2
• /
• pp.99-103
• /
• 2000

This study was carried out to investigate incubating characteristics, LTSEM observation, nature of a disease of infected silkworms(bombyx mori), LD$\_$50/, optimum infective condition for mass production and infection percentage(%) on conservation periods. On the V8 media, the colony was 0.5∼2.0cm/8 days in diameter and white or slighty colored with a white fluffy to powdery appearance. The conidia was subglobos in shape, zig-zag appearance, 1-celled, hyaline and 3.2$\times$2.4 ㎛ in size on the average. The conidiophore was irregular grouped, hyaline, rounded or flask-shaped. The LD$\_$50/ values of the 2nd and 4th silkworms were each other 6.6142(Log) in natural temperature and humidity (25$\^{C}$, 65%). On optimum infective condition for mass production, all of preservation time(hr.) postinoculation in 1.0$\times$10$\^$8/ conidia/㎖ was over 97% and only 20 hr in 1.0$\times$10$\^$7/ condia/㎖ was over 90%.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.1 no.1
• /
• pp.35-40
• /
• 2000

• Journal of Life Science
• /
• v.9 no.2
• /
• pp.176-181
• /
• 1999

In order to understand molecular phylogenetics of silkworm (Bombyx mori), we analyzed the sequences of BmoMAR isolated from Bomhyx mori that is partial coding gene of transposase of mariner-like element(MLE). By pairwise comparing nucleotide sequences of BmoMAR with ten previously reported insect MLEs accessed in GeneBank, the average genetic distance was estimated to be 0.4840. The phylogenetics tree constructed from nine insect species except for human MLE(Hsmarl) by UPGMA method indicated that MLEs are divided into three clusters, and Drosophila mariutiana was independently subgrouped. Bombyx mori(BmoMAR) was subgrouped with microcaddishfly (Orthotrichia cristata), webworm(Atteva punctella), almond moth(Ephestia cautella), Hyalopora cecropia which we lepidoptera. Phylogenetics tree according to UPGMA principle, on the basis of informative nucleotide sequences of nine insect MLEs, indicated that Bombyx mori was more closely related to microcaddishfly(Orthotrichia cristata) and webworm (Atteva punctella) of lepidoptera. We suggest that insect MLEs are a useful key for studying molecular phylogenetics among intra species of insects.

• Journal of Sericultural and Entomological Science
• /
• v.30 no.2
• /
• pp.96-104
• /
• 1988

Vitellin, the major yolk protein of the silkworm, Bombyx mori was pruified, and its immunological properties and the quantitative changes during embryogenesis were studied. The ovary transplantation into male hosts was also carried out to find its effect on the yolk protein synthesis. The pupal vitellogenin and the egg vitellin of Bombyx mori were purified by DEAE-cellulose column chromatography. These two female specific proteins showed the same mobility in the polyacrylamide gel electrophoresis and the same reaction in the double immunodiffusion test. The immunological identity was also observed between the vitellins of Bombyx mori and Bombyx mandarina. The rudimentary ovaries transplanted into the male hosts of silkworms produced eggs without vitellin, indicating that the yolk precursors synthesized in other female organ beyond the ovary were necessary to produce vitellins. The major yolk protein, vitellin was disintegrated and utilized mostly during late stage of embryogenesis. It was different characteristics from the egg specific protein, which was utilized continuously from the early embryonic stage.

• Preventive Nutrition and Food Science
• /
• v.21 no.3
• /
• pp.165-170
• /
• 2016

Recent trial results suggest that the consumption of a low glycemic index (GI) diet is beneficial in the prevention of high blood glucose levels. Identifying active hypoglycemic substances in ordinary foods could be a significant benefit to the management of blood glucose. It has been hypothesized that noodles with Bombyx mori powder are a low GI food. We evaluated GI and changes in postprandial glucose levels following consumption of those noodles and compared them with those following consumption of plain wheat flour noodles (control) and glucose (reference) in healthy subjects. Thirteen males (age: $34.2{\pm}4.5years$, body mass index: $23.2{\pm}1.1kg/m^2$) consumed 75 g carbohydrate portions of glucose and the 2 kinds of noodle after an overnight fast. Capillary blood was measured at time 0 (fasting), 15, 30, 45, 60, 90, 120, and 180 min from the start of each food intake. The GI values were calculated by taking the ratio of the incremental area under the blood glucose response curve (IAUC) for the noodles and glucose. There was a significant difference in postprandial glucose concentrations at 30 and 45 min between the control noodles and the noodles with Bombyx mori powder: the IAUC and GI for the noodles with Bombyx mori powder were significantly lower than those for glucose and plain wheat flour noodles. The wheat flour noodles with Bombyx mori powder could help prevent an increase in postprandial glucose response and possibly provide an alternative to other carbohydrate staple foods for glycemic management.