• International Journal of Industrial Entomology and Biomaterials
• /
• 제17권1호
• /
• pp.157-163
• /
• 2008

Infection of pathogenic microsporidia, Nosema bombycis and Nosema mylitta (Chakrabarti and Manna, 2006) decreased egg production, fecundity, hatching % and increased sterile eggs in heavily infected mulberry silkmoth, Bombyx mori L. On an average a disease free moth laid upto 442.67 eggs with high hatching % (99.53) and less sterile eggs ($0.47{\sim}2.00%$). While an infected moth laid less number of eggs ($7.00{\sim}412.00$) with low hatching % ($32.437{\sim}98.643$) and high sterile eggs ($2.143{\sim}129.571$). Fecundity of disease free laying was highest (468.714) during season-1 then gradually decreased during season- 2 (414.000) to season- 3 (404.285). But fecundity of an infected laying was highest during season-2 and hatched eggs were lowest during season-2. Higher inoculums concentration of N. mylitta infected to 5th stage larva of mulberry silkworm drastically decreased the fecundity in season - 3 and lower inoculums concentration of N. bombycis decreased the fecundity in season-1 and 3. Season-3 was most effective season to decrease the fecundity and increase sterile eggs when both temperature and humidity were fluctuated from the optimum level.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제21권2호
• /
• pp.163-167
• /
• 2010

[ $\alpha$ ]Glucosidase (EC 3.2.1.20) is a glycosidase that hydrolyzes disaccharides, oligosaccharides, and polysaccharides resulting in the release of α-D-glucose. In this study, $\alpha$-glucosidase activity in the hemolymph and midgut of the mulberry silkworm Bombyx mori and Japanese oak silkmoth Antheraea yamamai was measured using maltose, sucrose, trehalose, and p-nitrophenyl $\alpha$-D-glucopyranoside as substrates. In general, hemolymph $\alpha$-glucosidase activity was higher in B. mori than in A. yamamai. In contrast, midgut $\alpha$-glucosidase activity was higher in A. yamamai than in B. mori for all of the substrates tested. $\alpha$-Glucosidase activity in the midgut of both B. mori and A. yamamai showed similar responses to changes in pH and temperature for all of the substrates tested. Native (7.5%) PAGE of hemolymph and midgut proteins from B. mori and A. yamamai followed by staining with 4-methylumbelliferyl $\alpha$-D-glucoside (MUG) indicated that the $\alpha$-glucosidases of these related lepidopterans are functionally similar but structurally different. In comparison to $\alpha$-glucosidase activity from A. yamamai, $\alpha$-glucosidase activity from B. mori was generally less sensitive to the $\alpha$-glucosidase inhibitors, 1-deoxynojirimycin (DNJ), acarbose, and voglibose when the activity was determined using maltose, sucrose, and trehalose.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제18권2호
• /
• 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
• /
• 제24권2호
• /
• pp.63-68
• /
• 2012

Osteoporosis is characterized by the reduced density of mineralized bone matrix. The loss of bone has been attributed to an imbalance between bone formation and bone resorption. The silkmoth is one of the famous traditional tonic medicines. Silkworm pupa was evaluated for its antiosteoporotic activity in an ovariectomized rat model of osteoporosis. The rats were ovariectomized at 6weeks of age and divided into 7 groups. All the groups were fed without calcium diet. The OVX rats were treated with water and silkworm powder for 6 weeks. In OVX rats, the body weight, feeding and water intake quantity did not show a significant change, but the silkworm pupa powder immediately before the eclosion of Yeonrokjam was significantly increased the bone mineral density in the femoral bone. The silkworm pupa powder increased the bone with increasing calcium in serum. These results also showed its protective action through promotion of bone formation. The silkworm pupa powder has a definite antiosteoporotic effect; similar to estrogen, it is especially effective for the prevention of bone fracture induced by estrogen deficiency. The silkworm pupa powder is a promising anti-osteoporotic agent that can prevent bone fractures in osteoporotic patients. The silkworm pupa powder does not show serious side effects because natural herbal medicine origin.

• BMB Reports
• /
• 제46권7호
• /
• pp.358-363
• /
• 2013

In this paper, we firstly reported a C-type lectin cDNA clone of 1029 bps from the larvae of A. Pernyi (Ap-CTL) using PCR and RACE techniques. The full-length cDNA contains an open reading frame encoding 308 amino acid residues which has two different carbohydrate-recognition domains (CRDs) arranged in tandem. To investigate the biological activities in the innate immunity, recombinant Ap-CTL was expressed in E. coli with a 6-histidine at the amino-terminus (Ap-rCTL). Besides acted as a broad-spectrum recognition protein binding to a wide range of PAMPs and microorganisms, Ap-rCTL also had the ability to recognize and trigger the agglutination of bacteria and fungi. In the proPO activation assay, Ap-rCTL specifically restored the PO activity of hemolymph blocked by anti-Ap-rCTL antibody in the presence of different PAMPs or microorganisms. In summary, Ap-rCTL plays an important role in insect innate immunity as an pattern recognition protein.

• Journal of Microbiology and Biotechnology
• /
• 제30권9호
• /
• pp.1367-1378
• /
• 2020

The polyphagous eri silk moth, Samia ricini, is associated with various symbiotic gut bacteria believed to provide several benefits to the host. The larvae of S. ricini were subjected to isolation of gut bacteria using culture-dependent 16S rRNA generic characterization, metagenomics analysis and qualitative enzymatic assays. Sixty culturable aerobic gut bacterial isolates comprising Firmicutes (54%) and Proteobacteria (46%); and twelve culturable facultative anaerobic bacteria comprising Proteobacteria (92%) and Firmicutes (8%) were identified inhabiting the gut of S. ricini. The results of metagenomics analysis revealed the presence of a diverse community of both culturable and un-culturable gut bacteria belonging to Proteobacteria (60%) and Firmicutes (20%) associated with seven orders. An analysis of the results of culturable isolation indicates that these bacterial isolates inhabited all the three compartments of the gut. Investigation on persistence of bacteria coupled with metagenomics analysis of the fifth instar suggested that bacteria persist in the gut across the different instar stages. In addition, enzymatic assays indicated that 48 and 75% of culturable aerobic, and 75% of anaerobic gut bacterial isolates had cellulolytic, lipolytic and nitrate reductase activities, thus suggesting that they may be involved in food digestion and nutritional provision to the host. These bacterial isolates may be good sources for profiling novel genes and biomolecules for biotechnological application.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제14권2호
• /
• pp.113-119
• /
• 2007

Tropical tasar silkmoth Antheraea mylilta D. is an economically important insect. The wild nature and above all unsynchronized emergence of moths lead to impairment in reproductive activity. The mating in moths is low (64%-70%), leaving about 30-36% of potential females unused for seed (= egg) production. Delay in mating adversely affects the reproductive performance such as mating behaviour, fecundity and fertility. Females are more severely affected by mating delay than males. Therefore, a study was under taken to develop a method to overcome the problem so that the production of layings can be increased to meet the ever increasing demand. It was revealed from the study that out of 16 possible age combinations (from the age groups of day 0 to day 3), female and male of day 0 (4-8 hours old) excel in their reproductive performance than others (with 94.4% mating success, 284 fecundity and 91.5% hatching). Reproductive performance declined significantly even if one of the parents was older. When either of the mating pair was 1 day old, the mating declined by 28%; fecundity by 32.8%; and hatching by 40.8%. The insemination of eupyrene sperm was declined by 35.2% when both the parents are 1 day old. Mating duration of 8 hours resulted in insemination of $8.3{\times}10^5$ eupyrene sperms, which was declined by 31.6%, 48% and 55% upon lowering of mating duration to 6 hr, 4 hr and 2 hr were maintained respectively.

• 한국잠사곤충학회지
• /
• 제51권2호
• /
• pp.211-217
• /
• 2013

일반적으로 누에나방의 평균 생존시수는 암컷과 수컷이 각각 8일과 5일로 알려져 있다. 그러나 J037 품종의 성충 수명은 상당히 길며, 반대로 Daizo(sdi) 품종은 상당히 짧은 성충 수명 특성을 갖고 있다. 이러한 누에 품종 간 성충 수명의 차이는 유전적 차이에 따른 현상으로 추정되어 왔다. 본 연구에서는 장단명누에 품종의 발현유전자를 분석함으로써 누에 수명 관련 유전자를 탐색하여 그 특성을 분석하고자 하였다. 우선, 장명 수나방 mRNA를 사용하여 cDNA 유전자은행을 제작하고, 제작된 유전자은행으로부터 2,688개 클론을 무작위 선발한 후 장단명 수나방 cDNA를 각각의 탐침으로 차별화선별을 수행하였다. 본 연구에서 차별화 발현하는 193개의 클론을 선발하여 EST 상동성 분석을 통해 최종적으로 154개의 J037 수나방 수명 관련 독립유전자를 선발할 수 있었는데, 장명 탐침에서 과발현하는 124개와 단명 탐침에서 과발현하는 30개로 구성된다. 154개 독립유전자 중 가장 많은 발현빈도수를 보인 유전자는 cytochrome oxidase subunit-1으로서 모두 9회로 확인되었고, 현재까지 기능에 관해 알려진 바 없는 1-50번 독립유전자가 5회로 두 번째로 높은 발현빈도를 보였다. 154개 선발 독립유전자를 기능별로 분류한 결과, unclassified protein군에 가장 많은 24%의 독립유전자가 포함되어 있었다. 본 연구에서 두 번째로 발현빈도가 높은 클론(ID;1-50)의 염기서열 및 아미노산 서열을 분석하였는데, 1-50번 유전자는 전체 1,523 bp 염기로 구성되어 있으며, 723개 염기쌍이 240개의 아미노산을 coding 하고 있었다. 본 연구에서 선발된 주요 수명 관련 유전자는 국제유전자은행 EST database에 등록하였다.

• 생명과학회지
• /
• 제18권3호
• /
• pp.409-413
• /
• 2008

작잠 arylphorin 항 혈청을 사용하여 천잠, 가중나무 산누에 나방 및 옥색긴꼬리 산누에나방의 5령 유충의 혈림프, 피부, 지방체, 중장 및 실샘에 대한 종(species) 공통항원의 존재 여부를 비교${\cdot}$검토하였다. 4개종은 혈림프, 피부, 지방체, 중장 실샘 등 종별 조직에 따라 다소간 검출유무의 차이는 있으나 작잠 arylphorin 항 혈청에 대한 공통항원의 존재는 4종의 야생곤충 모두에서 확인되었으며, 특히 혈림프에서 가장 강력한 항원-항체 반응이 관찰되었다. 이상의 결과에서 A. pernyi arylphorin은 천잠 등 4개의 공시곤충들의 공통 조상유전자로부터 유래한 단백질일 가능성이 높은 것으로 사료된다.