The anti-inflammatory properties of silkworm pupa peptide(SPP)have been recognized for their potential benefits in colitis treatment.However,the underlying mechanism of SPP in colitis animal models remains unclear.The...The anti-inflammatory properties of silkworm pupa peptide(SPP)have been recognized for their potential benefits in colitis treatment.However,the underlying mechanism of SPP in colitis animal models remains unclear.The objective of our work was to investigate the improving effect and the mechanism of action of SPP on a mouse model of dextran sulfate sodium(DSS)-induced colitis.The findings suggested that SPP effectively eased ulcerative colitis(UC)symptoms in mice by decreasing disease activity index,ameliorating histopathological injury,and decreasing serum and colonic markers of inflammation.In addition,our research findings demonstrated that SPP restored intestinal barrier function by increasing the production of tight junction proteins such as zonula occludens-1(ZO-1),claudin-1,claudin-3,occludin,and adherens junction protein E-cadherin1.Further,SPP supplementation enhanced the concentration of short-chain fatty acids and positively altered the makeup of the gut bacteria in the mice's gut.These findings underscore SPP's ability to slow the progression of colitis and point to its possible use as a functional component in dietary supplements for the prevention of early-stage colitis.展开更多
The CRISPR-Cas13 system,an RNA-guided editing tool,has emerged as a highly efficient and stable RNA editing technique.Although the CRISPR-Cas13 system has been developed in several insect species,its application in le...The CRISPR-Cas13 system,an RNA-guided editing tool,has emerged as a highly efficient and stable RNA editing technique.Although the CRISPR-Cas13 system has been developed in several insect species,its application in lepidopterans has not yet been reported.In the present study,we evaluated the RNA cleavage activity of the CRISPR-Cas13 system in the silkworm(Bombyx mori),a model lepidopteran insect,both ex vivo and in vivo.We established two stable silkworm BmE cell lines expressing PspCas13b and CasRx,respectively.Further analysis demonstrated that both PspCas13b and CasRx effectively down-regulated the transcription of exogenouslyintroduced target and endogenous genes in these cell lines.In addition,we generated two transgenic silkworm strains,one expressing CasRx and the other expressing RNA-guided CRISPR RNA targeting Sex combs reduced(Scr).Further crossing experiments showed that CasRx induced a down-regulation of Scr transcription in silkworms,which impaired systemic growth of larvae.Overall,this study demonstrated that the CRISPR-Cas13RNA editing system works efficiently in the silkworm,providing a potential alternative approach for RNA manipulation in lepidopteran insects.展开更多
[Objective] To study the cocoon traits of wild silkworm descendants. [Method] In the selective breeding of domesticated raising wild silkworm and wild silkworm descendants, investigation on the traits of the built coc...[Objective] To study the cocoon traits of wild silkworm descendants. [Method] In the selective breeding of domesticated raising wild silkworm and wild silkworm descendants, investigation on the traits of the built cocoons was carried out. [Result] The pointed traits of cocoons displayed obviously in the wild silkworm descendants, its pointed parts were consistent with the rear part of silkworm chrysalis, and the female silkworm has slight difference, indicating the silkworm co- coon pointed trait was hereditary. [Conclusion] This study provided references for the study of silkworm cocoon traits of wild silkworm descendant and guides the selective breeding of silkworm variety.展开更多
[ Objective] The aim of this study was to investigate effects of various inducers on the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm. [ Method] Referring to the mRNA ...[ Objective] The aim of this study was to investigate effects of various inducers on the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm. [ Method] Referring to the mRNA sequence of CYP305 B1 V1 Gene published in GenBank for wild mulberry silkworm, one pair of primers was designed, and the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm treated by NaF, rutin, cypermethrin and ecdysone was also analyzed by the semi - quantitative RT - PCR. Furthermore, homology comparison and phylogenetic analysis for amino acid sequences of this gene were studied. [ Result] Rutin, cypermethrin and NaF had effects on the expression of P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm, while ecdysone had no significant effect. Homology comparison for amino acids indicated that the amino acid sequence of this gene was the most similar to that of CYP305 B1 gene in Bombyx mori with 100% amino acid identity, and highly similar to those of Tribolium casmneum CYP305A1, Apis mellifera CYP305A1, Drosophi- la melanogaster CYP305A1, Anopheles gambiae CYP305A2and Culex pipiens quinquefasciatus CYP2LI. [ Conclusion] CYP305 B1 V1 Gene of wild mulberry silkworm is likely to mainly take part in the metabolism of exogenous compounds, which is of great significance for revealing the function of cytochrome P450 and the metabolic mechanism of different drugs.展开更多
[Objective] The aim of this research was to study the expression of silkworm attacin gene induced by some different microorganisms.[Method] Three kinds of microorganism,BmNPV,JM109 and Agrobacterium LBA4404,were inges...[Objective] The aim of this research was to study the expression of silkworm attacin gene induced by some different microorganisms.[Method] Three kinds of microorganism,BmNPV,JM109 and Agrobacterium LBA4404,were ingested to silkworm and the expression profile of attacin gene in hemocyte and fat body was detected by semi-quantitative PCR.And subsequently,the PCR products were cloned and sequenced for further analysis.[Result] A specific band,about 800 bp,appeared in fat body of all induced silkworms.As indicated by the results of cloning and sequencing(GenBank accession number:FJ373019),the band was produced because the 2 introns existing in normal expression form were not spliced.Furthermore,when the extended expression sequence was translated into amino acids,the translation stopped earlier by the stop codon TGA at the 5' end of the first intron of the original sequence,leading the loss of attacin C terminus.[Conclusion] There were two splicesomes of attacin gene,which had reference value to study the role of the attacin gene in silkworm immunity.展开更多
[Objective] The research aimed to obtain an effectively-decomposing strain of silkworm chrysalis protein and discuss its enzymatic properties.[Method] The effectively-decomposing bacteria of protein was isolated from ...[Objective] The research aimed to obtain an effectively-decomposing strain of silkworm chrysalis protein and discuss its enzymatic properties.[Method] The effectively-decomposing bacteria of protein was isolated from the decayed silkworm chrysalis by using dilution plate and its enzymatic properties were tested after primary screening and second screening.The enzyme activity was determined and the intermediate and small molecule protein content in silkworm chrysalis was measured after solid-state fermentati...展开更多
[Objective] The study aimed to breed eminent mulbery wild silb with hypersilk.[Method] Eminent mulberry wild silkworm basic materials Ye A and Ye B were bred by distant complex crossing of wild mulberry silkworm with ...[Objective] The study aimed to breed eminent mulbery wild silb with hypersilk.[Method] Eminent mulberry wild silkworm basic materials Ye A and Ye B were bred by distant complex crossing of wild mulberry silkworm with strong stress resistance and hypersilkgeneous silkworm,then hybridized with Japanese silkworm strain,the new silkworm variety "Yesanyuan" with healthiness and hypersilkgene was bred.[Ressult]The results of laboratory identification and rural productive test in Jiangsu Province showed that it has excellent feeding habit,strong stress resistance,high yield,excellent silk quality and excellent fecundity.The new silkworm variety "Yesanyuan" had been approved by Silkworm Variety Evaluation Commission of Jiangsu Province in 2008,it is suitable to rear in Yangtze River catchment for Spring and Autumn,North sericultural area for all-year.[Conclusion] The study is helpful for the development of silkworm industry.展开更多
A simple and green technique has been developed to prepare hierarchical biomorphic ZrO2- CeO2, using silkworm silk as the template. Different from traditional immersion technics, the whole synthesis process depends mo...A simple and green technique has been developed to prepare hierarchical biomorphic ZrO2- CeO2, using silkworm silk as the template. Different from traditional immersion technics, the whole synthesis process depends more on the restriction or direction functions of the silkworm silk template. The analytic results showed that ZrO2-CeO2 exhibited a well-crystallized hierarchically interwoven hollow fiber structure with 16-28 μm in diameter. The grain size of the sample calcined at 800 ℃ was about 14 nm. Consequently, the interwoven meshwork at three dimensions is formed due to the direction of biotemplate. The action mechanism is summarily discussed here. It may bring the biomorphic ZrO2-CeO2 nanomaterials with hierarchical interwoven structures to more applications, such as catalysts.展开更多
Silkworm pupa is a nourishing food with high nutritional value,but its consumption has been greatly limited given its allergenicity.Enzyme hydrolytic technique is recognized as an effective method to reduce the allerg...Silkworm pupa is a nourishing food with high nutritional value,but its consumption has been greatly limited given its allergenicity.Enzyme hydrolytic technique is recognized as an effective method to reduce the allergenicity of protein.In this study,we aimed to investigate the effect of enzymolysis on the allergenicity of silkworm pupa.Crude silkworm pupa protein was extracted through alkali extraction and acid precipitation,which included 5 proteins with the molecular weights ranging from 34 kDa to 76 kDa,and silkworm pupa were then hydrolyzed by alkaline protease.The allergenicity of silkworm pupa protein and its enzymatic hydrolysates was evaluated by establishing BALB/c mice model,and the mice were immunized via intragastric gavage and intraperitoneal injection,respectively.The results indicated that the intraperitoneal inj ection immunization route induced more by detecting with antibodies,histamine and Th2-related cytokines.Moreover,mice treated with silkworm pupa protein peptide displayed no obvious allergic symptoms,indicating that enzyme hydrolytic technique could significantly reduce the allergenicity of silkworm pupa.展开更多
[Objective] The aim of this study was to optimize the conditions of chitinase-produce strains.[Method] A kind of screened chitinase-produce strain G-254 was habituated cultured,and then the single factor experiment wa...[Objective] The aim of this study was to optimize the conditions of chitinase-produce strains.[Method] A kind of screened chitinase-produce strain G-254 was habituated cultured,and then the single factor experiment was carried out to explore the effects of different carbon source,nitrogen source and inorganic salt on the activity of produced chitinase;the response surface test was used to determine the optimal conditions for chitinase production.[Result] The optimal conditions for chitinase production were：8% of glucose,5% of beef extract and 0.07% of MgSO4,and the activity of chitinase reached the maximal value（6.86 U）under these conditions.[Conclusion] The study improved the activity of chitinase produced by strain G-254 and provided good foundation for industrial production.展开更多
Metabolism of hydrogen peroxide in the course of embryonic development ofsilkworm (variety Guang) was determined by using colorimetric analysis and oxygen electrodemethod. The results indicated that: 1) In the course ...Metabolism of hydrogen peroxide in the course of embryonic development ofsilkworm (variety Guang) was determined by using colorimetric analysis and oxygen electrodemethod. The results indicated that: 1) In the course of fertilization (0-4 h after egg laying), thelevel of H_2O_2 content reached its peak value at 2.5 h of the developmental course and the activity ofsuperoxidase dismutase (SOD) was at higher level while the activity of catalase (CAT) at the lowestcorrespondingly; 2) The H_2O_2 content in embryo, in which the diapause of eggs was being relievedthrough treatment with hydrochloric acid on time in the course of embryonic development, wassignificantly higher than that of diapause eggs except the lower level showed in the embryo whenthe development of it went on for 168~216 h and the activity of SOD reached, lower and higher,tWo peaks in 72 and 168 h after egg-laying, respectively, and was significantly higher in late stagewhile the activity of CAT was shown with a stable level in the period of 72-192 h after egg-laying,and, after then, a rapid rising occurred in the embryo. The level of the CAT activity in embryowas shown significantly lower than that in diapause eggs in early period and higher in late stage ofegg development; 3) In the course of formation of diapause in eggs, the level of H_2O_2contentchanged smoothly and the activity of SOD changed vigorously in early period, and kept stable statelater; and the CAT activity increased gradually; while in the course of relief of diapause under ontime-treatment with hydrochloric acid, the level of H_2O_2 was significantly higher than that indiapause eggs and the SOD activity displayed a new peak value and significantly rose in later stage,while the activity of CAT in relieving embryo from diapause was signincantly lower than that indiapause eggs. Combining the results obtained in other researches with those from ours mentionedabove, we suggest that the metabolism of H_2O_2 might be of importance in the courses of formationand relief of diapause in silkworm eggs. Maybe the esterase A4 timer hypothesis and themicropylar barrier to oxygen hypothesis could be integrated for explanation of the course offormation and relief of diapause in silkworm eggs.展开更多
Through statistical analysis on questionnaire survey data from 136 silkworm eggs producing farms in China,it was concluded that most silkworm eggs producing farms had such problems as follows: old production facilitie...Through statistical analysis on questionnaire survey data from 136 silkworm eggs producing farms in China,it was concluded that most silkworm eggs producing farms had such problems as follows: old production facilities and poor production condition,heavy staff burden,weak scientific and technological support,small operation scale and heavy surplus production capacity; narrow silkworm eggs sale channels and stubborn regional segmentation,insufficient innovation and lack of technological support for diversified expansion. All these problems led to low labor productivity,low asset utilization rate and poor economic benefit in silkworm eggs producing farms in China. Except the provinces( regions) of Guangxi,Guangdong and Yunnan,the silkworm eggs producing farms in other provinces were generally at deficit condition. In the light of ownership,although silkworm eggs producing farms of different ownership systems were in the red,those of the private sector had the minimum deficit. Based on these findings,it is proposed to deepen system reformation of silkworm eggs producing farms,loosen control to price and circulation of silkworm eggs,implement large-scaled production and operation,speed up scientific and technological innovation,expand diversified development channels,and reinforce government support so as to increase production and operation benefits of silkworm eggs producing farms in China.展开更多
Silkworm pupa protein(SPP)that obtained by traditional method usually had a high fat content,which would impose restrictions on the further use of SPP.Herein,various functionalized ionic liquids(ILs)were used to extra...Silkworm pupa protein(SPP)that obtained by traditional method usually had a high fat content,which would impose restrictions on the further use of SPP.Herein,various functionalized ionic liquids(ILs)were used to extract SPP from silkworm pupae,the structure-performance relationship of ILs with their SPP separation performance were explored at the same time.The research showed that the maximum extraction yield of SPP was up to 62.6%with less than 0.5%low fat content by using 1-ethyl-3-methylimidazolium chloride([Emim]Cl),when the dissolution experiment was conducted at 90°C for 24 h with ethanol bath as the regeneration solvent.Comparing with the structure of raw material,the regenerated SPP maintained the native protein backbone.Meanwhile,all regenerated SPP showed a decreased crystallinity,which also exhibited decreased fraction of theα-helix comparing to thatβ-sheet united with coil random structures.展开更多
[Objective] Taking silkworm （Bombyx mori） as the test material, the research aimed to study the toxicity effects of Euphorbiafischeriana Steud. against the insects in Lepidoptera. [ Methods ] Water extract was prepa...[Objective] Taking silkworm （Bombyx mori） as the test material, the research aimed to study the toxicity effects of Euphorbiafischeriana Steud. against the insects in Lepidoptera. [ Methods ] Water extract was prepared with fresh perennial E. fischer/ana Steud. , which was applied in silkworm with different methods including daubing the extract on silkworm back, soaking silkworm in the extract and feeding silkworm with the mulberry leaves daubed by the extract. [ Re- suits] Those silkworms whose backs were daubed with the water extract had no obvious poisoning symptom. The silkworms soaked for 1 and 3 min could be survived for about 7 d; the silkworms soaked for 5 min could be survived for about 2 d; and the silkworms soaked for 15 rain could be survived for 10 h at most. Those silk- worms fed with mulberry leaves daubed by water extract completely died after 2 d. [ Conduslons ] The water extract of E. fischer/ana Steud. had significant contact toxicity and stomach poisoning against silkworm.展开更多
Fluorescent silk is fundamentally important for the development of future tissue engineering scaffolds.Despite great progress in the preparation of a variety of colored silks,fluorescent silk with enhanced mechanical ...Fluorescent silk is fundamentally important for the development of future tissue engineering scaffolds.Despite great progress in the preparation of a variety of colored silks,fluorescent silk with enhanced mechanical properties has yet to be explored.In this study,we report on the fabrication of intrinsically super-strong fluorescent silk by feeding Bombyx mori silkworm carbon nanodots(CNDs).The CNDs were incorporated into silk fibroin,hindering the conformation transformation,confining crystallization,and inducing orientation of mesophase.The resultant silk exhibited super-strong mechanical properties with breaking strength of 521.9±82.7 MPa and breaking elongation of 19.2±4.3%,improvements of 55.1%and 53.6%,respectively,in comparison with regular silk.The CNDs-reinforced silk displayed intrinsic blue fluorescence when exposed to 405 nm laser and exhibited no cytotoxic effect on cells,suggesting that multi-functional silks would be potentially useful in bioimaging and other applications.展开更多
1-deoxynojirimycin (1-DNJ) contents in the silkworm,Bombyx mori,at different developmental stages and tissues were investigated by using reverse-phase high-performance liquid chromatography. The 1-DNJ contents of silk...1-deoxynojirimycin (1-DNJ) contents in the silkworm,Bombyx mori,at different developmental stages and tissues were investigated by using reverse-phase high-performance liquid chromatography. The 1-DNJ contents of silkworm larvae change significantly with their developmental stages. The male larvae showed higher accumulation efficiency of 1-DNJ than the females and also a significant variation was observed among the silkworm strains. The present results show that tissue distribution of 1-DNJ was significantly higher in blood,digestive juice,and alimentary canal,but no 1-DNJ was observed in the silkgland. Moreover,1-DNJ was not found in silkworms fed with artificial diet that does not contain mulberry leaf powder. This proves that silkworms obtain 1-DNJ from mulberry leaves; they could not synthesize 1-DNJ by themselves. The accumulation and excretion of 1-DNJ change periodically during the larval stage. There was no 1-DNJ in the newly-hatched larvae and 1-DNJ was mainly accumulated during the early and middle stages of every instar,while excreted at later stages of larval development. Further,it is possible to extract 1-DNJ from the larval feces and it is optimal to develop the 1-DNJ related products for diabetic auxiliary therapy.展开更多
MicroRNAs （miRNAs） constitute a novel, extensive class of small RNAs （-21 nucleotides）, and play important gene-regulation roles during growth and development in various organisms. Here we conducted a homology sea...MicroRNAs （miRNAs） constitute a novel, extensive class of small RNAs （-21 nucleotides）, and play important gene-regulation roles during growth and development in various organisms. Here we conducted a homology search to identify homologs of previously validated miRNAs from silkworm genome. We identified 24 potential miRNA genes, and gave each of them a name according to the common criteria. Interestingly, we found that a great number of newly identified miRNAs were conserved in silkworm and Drosophila, and family alignment revealed that miRNA families might possess single nucleotide polymorphisms, miRNA gene clusters and possible functions of complement miRNA pairs are discussed.展开更多
Silkworm powder containing 1-deoxynojirimycin (DNJ) has α-glucosidase inhibitory activity and is promising as a complementary and alternative medicine (CAM) agent in Japan. Silkworm powder produced in Korea was extra...Silkworm powder containing 1-deoxynojirimycin (DNJ) has α-glucosidase inhibitory activity and is promising as a complementary and alternative medicine (CAM) agent in Japan. Silkworm powder produced in Korea was extracted with 75% ethanol. The extract was derivatized with 9-fluorenylmethyl chloroformate (FMOC-Cl), and DNJ-FMOC content was measured by HPLC. Then, alfa-glucosidase inhibition by silkworm and mulberry powder in pig liver crude enzyme was assayed using 4-nitrophenyl-alfa-D-glucopyranoside as a substrate. Silkworm powder DNJ content (0.39 to 0.58%) was higher than that in mulberry powder (0.08 to 0.12%). The alfa-glucosidase inhibitory activity of silkworm powder was more potent than that of mulberry leaves and green tea. Silkworm powder DNJ was stable upon heating to 121?C for up to 15 min.展开更多
Peptide hydrolysates of silkworm pupae protein with molecular weight of less than 5000 Da were prepared by ultrafiltration. The extracted peptide hydrolysates of silkworm pupae protein had inhibitory action on angiote...Peptide hydrolysates of silkworm pupae protein with molecular weight of less than 5000 Da were prepared by ultrafiltration. The extracted peptide hydrolysates of silkworm pupae protein had inhibitory action on angiotensin-I-converting enzyme activity in vitro. The hydrolysates were orally administered to spontaneously hypertensive rats (SHR) in one period and long-term (four weeks). The results showed that the systolic blood pressure (SBP) of the treatment groups decreased in a dose-related manner. After one oral administration of silkworm protein hydrolysates with doses of 60, 20 and 5 mg/kg, the SBP of SHR decreased by 21.5, 13.8, and 9.0 mmHg in 1.5 h. After four weeks of the treatment in 80 mg/kg, the SBP decreased by 25 mmHg, with the antihypertensive activity close to 4 mg/kg of captopril;the SBP of the 40 mg/kg dose group also decreased by 17.5 mmHg. The peptide hydrolysate did not affect the SBP in normal, non-hypertensive rats in one period and long-term treatments. The acute toxicity research showed that the peptide hydrolysates were safe and without side effects. This research would be helpful in exploring the silkworm protein peptides as functional components for the antihypertension treatment.展开更多
Most animals have the ability to adapt, to some extends and in different ways, the variation or disturbance of environment. In our experiments, we forced a silkworm caterpillar to spin two, three or four thin cocoons ...Most animals have the ability to adapt, to some extends and in different ways, the variation or disturbance of environment. In our experiments, we forced a silkworm caterpillar to spin two, three or four thin cocoons by taking it out from the cocoon being constructed. The mechanical properties of these cocoons were studied by static tensile tests and dynamic mechanical thermal analysis. Though external disturbances may cause the decrease in the total weight of silk spun by the silkworm, a gradual enhancement was interestingly found in the mechanical properties of these thin cocoons. Scanning electron microscopy observations of the fractured specimens of the cocoons showed that there exist several different energy dissipation mechanisms occurred simultaneously at macro-, meso-, and micro-scales, yielding a superior capacity of cocoons to adsorb the energy of possible attacks from the outside and to protect efficiently its pupa against damage. Through evolution of millions of years, therefore, the silkworm Bombyx mori seems to have gained the ability to adapt external disturbances and to redesign a new cocoon with optimized protective function when its first cocoon has been damaged for some reasons.展开更多
基金supported by the National Key Research and Development Program of China(2023YFF1103802)。
文摘The anti-inflammatory properties of silkworm pupa peptide(SPP)have been recognized for their potential benefits in colitis treatment.However,the underlying mechanism of SPP in colitis animal models remains unclear.The objective of our work was to investigate the improving effect and the mechanism of action of SPP on a mouse model of dextran sulfate sodium(DSS)-induced colitis.The findings suggested that SPP effectively eased ulcerative colitis(UC)symptoms in mice by decreasing disease activity index,ameliorating histopathological injury,and decreasing serum and colonic markers of inflammation.In addition,our research findings demonstrated that SPP restored intestinal barrier function by increasing the production of tight junction proteins such as zonula occludens-1(ZO-1),claudin-1,claudin-3,occludin,and adherens junction protein E-cadherin1.Further,SPP supplementation enhanced the concentration of short-chain fatty acids and positively altered the makeup of the gut bacteria in the mice's gut.These findings underscore SPP's ability to slow the progression of colitis and point to its possible use as a functional component in dietary supplements for the prevention of early-stage colitis.
基金supported by the National Natural Science Foundation of China(32070496,32370555)Fundamental Research Funds for the Central Universities(SWU120033)Technology Innovation and Application Development Program of Chongqing(CSTB2024TIADKPX0023)。
文摘The CRISPR-Cas13 system,an RNA-guided editing tool,has emerged as a highly efficient and stable RNA editing technique.Although the CRISPR-Cas13 system has been developed in several insect species,its application in lepidopterans has not yet been reported.In the present study,we evaluated the RNA cleavage activity of the CRISPR-Cas13 system in the silkworm(Bombyx mori),a model lepidopteran insect,both ex vivo and in vivo.We established two stable silkworm BmE cell lines expressing PspCas13b and CasRx,respectively.Further analysis demonstrated that both PspCas13b and CasRx effectively down-regulated the transcription of exogenouslyintroduced target and endogenous genes in these cell lines.In addition,we generated two transgenic silkworm strains,one expressing CasRx and the other expressing RNA-guided CRISPR RNA targeting Sex combs reduced(Scr).Further crossing experiments showed that CasRx induced a down-regulation of Scr transcription in silkworms,which impaired systemic growth of larvae.Overall,this study demonstrated that the CRISPR-Cas13RNA editing system works efficiently in the silkworm,providing a potential alternative approach for RNA manipulation in lepidopteran insects.
基金Supported by the Agricultural Fund Project of Ministry of Science and Technology(Y0415)the China Agriculture Research System(Sericulture)~~
文摘[Objective] To study the cocoon traits of wild silkworm descendants. [Method] In the selective breeding of domesticated raising wild silkworm and wild silkworm descendants, investigation on the traits of the built cocoons was carried out. [Result] The pointed traits of cocoons displayed obviously in the wild silkworm descendants, its pointed parts were consistent with the rear part of silkworm chrysalis, and the female silkworm has slight difference, indicating the silkworm co- coon pointed trait was hereditary. [Conclusion] This study provided references for the study of silkworm cocoon traits of wild silkworm descendant and guides the selective breeding of silkworm variety.
文摘[ Objective] The aim of this study was to investigate effects of various inducers on the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm. [ Method] Referring to the mRNA sequence of CYP305 B1 V1 Gene published in GenBank for wild mulberry silkworm, one pair of primers was designed, and the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm treated by NaF, rutin, cypermethrin and ecdysone was also analyzed by the semi - quantitative RT - PCR. Furthermore, homology comparison and phylogenetic analysis for amino acid sequences of this gene were studied. [ Result] Rutin, cypermethrin and NaF had effects on the expression of P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm, while ecdysone had no significant effect. Homology comparison for amino acids indicated that the amino acid sequence of this gene was the most similar to that of CYP305 B1 gene in Bombyx mori with 100% amino acid identity, and highly similar to those of Tribolium casmneum CYP305A1, Apis mellifera CYP305A1, Drosophi- la melanogaster CYP305A1, Anopheles gambiae CYP305A2and Culex pipiens quinquefasciatus CYP2LI. [ Conclusion] CYP305 B1 V1 Gene of wild mulberry silkworm is likely to mainly take part in the metabolism of exogenous compounds, which is of great significance for revealing the function of cytochrome P450 and the metabolic mechanism of different drugs.
基金Supported by Educational Commission of Shaanxi Province(08JK211)Special Scientific Research Foundation Project of Ankang University(AYQDZR200711)~~
文摘[Objective] The aim of this research was to study the expression of silkworm attacin gene induced by some different microorganisms.[Method] Three kinds of microorganism,BmNPV,JM109 and Agrobacterium LBA4404,were ingested to silkworm and the expression profile of attacin gene in hemocyte and fat body was detected by semi-quantitative PCR.And subsequently,the PCR products were cloned and sequenced for further analysis.[Result] A specific band,about 800 bp,appeared in fat body of all induced silkworms.As indicated by the results of cloning and sequencing(GenBank accession number:FJ373019),the band was produced because the 2 introns existing in normal expression form were not spliced.Furthermore,when the extended expression sequence was translated into amino acids,the translation stopped earlier by the stop codon TGA at the 5' end of the first intron of the original sequence,leading the loss of attacin C terminus.[Conclusion] There were two splicesomes of attacin gene,which had reference value to study the role of the attacin gene in silkworm immunity.
基金Supported by Agricultural Key Project of Guangdong Province(2007A0201000043)Key Bidding Projects in Key Fields of Guangdong and Hongkong(2006A25001002)Special Fund for the Construction of National Modern Agro-industry Technology System~~
文摘[Objective] The research aimed to obtain an effectively-decomposing strain of silkworm chrysalis protein and discuss its enzymatic properties.[Method] The effectively-decomposing bacteria of protein was isolated from the decayed silkworm chrysalis by using dilution plate and its enzymatic properties were tested after primary screening and second screening.The enzyme activity was determined and the intermediate and small molecule protein content in silkworm chrysalis was measured after solid-state fermentati...
基金Supported by National Key Technology R&D Program(2006BAD06B03)~~
文摘[Objective] The study aimed to breed eminent mulbery wild silb with hypersilk.[Method] Eminent mulberry wild silkworm basic materials Ye A and Ye B were bred by distant complex crossing of wild mulberry silkworm with strong stress resistance and hypersilkgeneous silkworm,then hybridized with Japanese silkworm strain,the new silkworm variety "Yesanyuan" with healthiness and hypersilkgene was bred.[Ressult]The results of laboratory identification and rural productive test in Jiangsu Province showed that it has excellent feeding habit,strong stress resistance,high yield,excellent silk quality and excellent fecundity.The new silkworm variety "Yesanyuan" had been approved by Silkworm Variety Evaluation Commission of Jiangsu Province in 2008,it is suitable to rear in Yangtze River catchment for Spring and Autumn,North sericultural area for all-year.[Conclusion] The study is helpful for the development of silkworm industry.
文摘A simple and green technique has been developed to prepare hierarchical biomorphic ZrO2- CeO2, using silkworm silk as the template. Different from traditional immersion technics, the whole synthesis process depends more on the restriction or direction functions of the silkworm silk template. The analytic results showed that ZrO2-CeO2 exhibited a well-crystallized hierarchically interwoven hollow fiber structure with 16-28 μm in diameter. The grain size of the sample calcined at 800 ℃ was about 14 nm. Consequently, the interwoven meshwork at three dimensions is formed due to the direction of biotemplate. The action mechanism is summarily discussed here. It may bring the biomorphic ZrO2-CeO2 nanomaterials with hierarchical interwoven structures to more applications, such as catalysts.
基金supported by Special Project on the Integration of Industry,Education and Research of Guangdong Provine(2013B090600060)National Key R&D Program of China(2018YFC1604205)National Natural Science Foundation of China(31760431)。
文摘Silkworm pupa is a nourishing food with high nutritional value,but its consumption has been greatly limited given its allergenicity.Enzyme hydrolytic technique is recognized as an effective method to reduce the allergenicity of protein.In this study,we aimed to investigate the effect of enzymolysis on the allergenicity of silkworm pupa.Crude silkworm pupa protein was extracted through alkali extraction and acid precipitation,which included 5 proteins with the molecular weights ranging from 34 kDa to 76 kDa,and silkworm pupa were then hydrolyzed by alkaline protease.The allergenicity of silkworm pupa protein and its enzymatic hydrolysates was evaluated by establishing BALB/c mice model,and the mice were immunized via intragastric gavage and intraperitoneal injection,respectively.The results indicated that the intraperitoneal inj ection immunization route induced more by detecting with antibodies,histamine and Th2-related cytokines.Moreover,mice treated with silkworm pupa protein peptide displayed no obvious allergic symptoms,indicating that enzyme hydrolytic technique could significantly reduce the allergenicity of silkworm pupa.
基金Supported by Science and Technology Support Project of Guangdong Academy of Agricultural Science and Technology(07-Supporting-04)Agricultural Research Projects in Guangdong Province (2007A0201000043)Earmarked Fund for Modern Agro-Industry Technology Research System of China~~
文摘[Objective] The aim of this study was to optimize the conditions of chitinase-produce strains.[Method] A kind of screened chitinase-produce strain G-254 was habituated cultured,and then the single factor experiment was carried out to explore the effects of different carbon source,nitrogen source and inorganic salt on the activity of produced chitinase;the response surface test was used to determine the optimal conditions for chitinase production.[Result] The optimal conditions for chitinase production were：8% of glucose,5% of beef extract and 0.07% of MgSO4,and the activity of chitinase reached the maximal value（6.86 U）under these conditions.[Conclusion] The study improved the activity of chitinase produced by strain G-254 and provided good foundation for industrial production.
文摘Metabolism of hydrogen peroxide in the course of embryonic development ofsilkworm (variety Guang) was determined by using colorimetric analysis and oxygen electrodemethod. The results indicated that: 1) In the course of fertilization (0-4 h after egg laying), thelevel of H_2O_2 content reached its peak value at 2.5 h of the developmental course and the activity ofsuperoxidase dismutase (SOD) was at higher level while the activity of catalase (CAT) at the lowestcorrespondingly; 2) The H_2O_2 content in embryo, in which the diapause of eggs was being relievedthrough treatment with hydrochloric acid on time in the course of embryonic development, wassignificantly higher than that of diapause eggs except the lower level showed in the embryo whenthe development of it went on for 168~216 h and the activity of SOD reached, lower and higher,tWo peaks in 72 and 168 h after egg-laying, respectively, and was significantly higher in late stagewhile the activity of CAT was shown with a stable level in the period of 72-192 h after egg-laying,and, after then, a rapid rising occurred in the embryo. The level of the CAT activity in embryowas shown significantly lower than that in diapause eggs in early period and higher in late stage ofegg development; 3) In the course of formation of diapause in eggs, the level of H_2O_2contentchanged smoothly and the activity of SOD changed vigorously in early period, and kept stable statelater; and the CAT activity increased gradually; while in the course of relief of diapause under ontime-treatment with hydrochloric acid, the level of H_2O_2 was significantly higher than that indiapause eggs and the SOD activity displayed a new peak value and significantly rose in later stage,while the activity of CAT in relieving embryo from diapause was signincantly lower than that indiapause eggs. Combining the results obtained in other researches with those from ours mentionedabove, we suggest that the metabolism of H_2O_2 might be of importance in the courses of formationand relief of diapause in silkworm eggs. Maybe the esterase A4 timer hypothesis and themicropylar barrier to oxygen hypothesis could be integrated for explanation of the course offormation and relief of diapause in silkworm eggs.
基金Supported by Specific Project of China Agricultural Industry Research System(NO.CARS-22)Special Project of the Ministry of Agriculture in 2011(No.NBN[2012]44)
文摘Through statistical analysis on questionnaire survey data from 136 silkworm eggs producing farms in China,it was concluded that most silkworm eggs producing farms had such problems as follows: old production facilities and poor production condition,heavy staff burden,weak scientific and technological support,small operation scale and heavy surplus production capacity; narrow silkworm eggs sale channels and stubborn regional segmentation,insufficient innovation and lack of technological support for diversified expansion. All these problems led to low labor productivity,low asset utilization rate and poor economic benefit in silkworm eggs producing farms in China. Except the provinces( regions) of Guangxi,Guangdong and Yunnan,the silkworm eggs producing farms in other provinces were generally at deficit condition. In the light of ownership,although silkworm eggs producing farms of different ownership systems were in the red,those of the private sector had the minimum deficit. Based on these findings,it is proposed to deepen system reformation of silkworm eggs producing farms,loosen control to price and circulation of silkworm eggs,implement large-scaled production and operation,speed up scientific and technological innovation,expand diversified development channels,and reinforce government support so as to increase production and operation benefits of silkworm eggs producing farms in China.
基金supported financially by the National Natural Science Foundation of China(Nos.81673400 and 21878292)。
文摘Silkworm pupa protein(SPP)that obtained by traditional method usually had a high fat content,which would impose restrictions on the further use of SPP.Herein,various functionalized ionic liquids(ILs)were used to extract SPP from silkworm pupae,the structure-performance relationship of ILs with their SPP separation performance were explored at the same time.The research showed that the maximum extraction yield of SPP was up to 62.6%with less than 0.5%low fat content by using 1-ethyl-3-methylimidazolium chloride([Emim]Cl),when the dissolution experiment was conducted at 90°C for 24 h with ethanol bath as the regeneration solvent.Comparing with the structure of raw material,the regenerated SPP maintained the native protein backbone.Meanwhile,all regenerated SPP showed a decreased crystallinity,which also exhibited decreased fraction of theα-helix comparing to thatβ-sheet united with coil random structures.
基金Supported by Research Project Plan in Chengde Medical College(200925)~~
文摘[Objective] Taking silkworm （Bombyx mori） as the test material, the research aimed to study the toxicity effects of Euphorbiafischeriana Steud. against the insects in Lepidoptera. [ Methods ] Water extract was prepared with fresh perennial E. fischer/ana Steud. , which was applied in silkworm with different methods including daubing the extract on silkworm back, soaking silkworm in the extract and feeding silkworm with the mulberry leaves daubed by the extract. [ Re- suits] Those silkworms whose backs were daubed with the water extract had no obvious poisoning symptom. The silkworms soaked for 1 and 3 min could be survived for about 7 d; the silkworms soaked for 5 min could be survived for about 2 d; and the silkworms soaked for 15 rain could be survived for 10 h at most. Those silk- worms fed with mulberry leaves daubed by water extract completely died after 2 d. [ Conduslons ] The water extract of E. fischer/ana Steud. had significant contact toxicity and stomach poisoning against silkworm.
基金sponsored by the National Key Research and Development Program of China(2016YFA0201700,2016YFA0201702)the Fundamental Research Funds for the Central Universities(2232019A3-06,2232019D3-02)+2 种基金the National Key Research and Development Program of China(2018YFC1105800)the National Natural Science Foundation of China(21674018,51903045)the Shanghai Belt and Road Joint Laboratory of Advanced Fiber and Low-Dimension Materials(18520750400).
文摘Fluorescent silk is fundamentally important for the development of future tissue engineering scaffolds.Despite great progress in the preparation of a variety of colored silks,fluorescent silk with enhanced mechanical properties has yet to be explored.In this study,we report on the fabrication of intrinsically super-strong fluorescent silk by feeding Bombyx mori silkworm carbon nanodots(CNDs).The CNDs were incorporated into silk fibroin,hindering the conformation transformation,confining crystallization,and inducing orientation of mesophase.The resultant silk exhibited super-strong mechanical properties with breaking strength of 521.9±82.7 MPa and breaking elongation of 19.2±4.3%,improvements of 55.1%and 53.6%,respectively,in comparison with regular silk.The CNDs-reinforced silk displayed intrinsic blue fluorescence when exposed to 405 nm laser and exhibited no cytotoxic effect on cells,suggesting that multi-functional silks would be potentially useful in bioimaging and other applications.
文摘1-deoxynojirimycin (1-DNJ) contents in the silkworm,Bombyx mori,at different developmental stages and tissues were investigated by using reverse-phase high-performance liquid chromatography. The 1-DNJ contents of silkworm larvae change significantly with their developmental stages. The male larvae showed higher accumulation efficiency of 1-DNJ than the females and also a significant variation was observed among the silkworm strains. The present results show that tissue distribution of 1-DNJ was significantly higher in blood,digestive juice,and alimentary canal,but no 1-DNJ was observed in the silkgland. Moreover,1-DNJ was not found in silkworms fed with artificial diet that does not contain mulberry leaf powder. This proves that silkworms obtain 1-DNJ from mulberry leaves; they could not synthesize 1-DNJ by themselves. The accumulation and excretion of 1-DNJ change periodically during the larval stage. There was no 1-DNJ in the newly-hatched larvae and 1-DNJ was mainly accumulated during the early and middle stages of every instar,while excreted at later stages of larval development. Further,it is possible to extract 1-DNJ from the larval feces and it is optimal to develop the 1-DNJ related products for diabetic auxiliary therapy.
基金Project supported by the Program for New Century Excellent Talentsin University (No. NCET-04-0531) and the National Basic ResearchProgram (973) of China (No. 2005CB12100)
文摘MicroRNAs （miRNAs） constitute a novel, extensive class of small RNAs （-21 nucleotides）, and play important gene-regulation roles during growth and development in various organisms. Here we conducted a homology search to identify homologs of previously validated miRNAs from silkworm genome. We identified 24 potential miRNA genes, and gave each of them a name according to the common criteria. Interestingly, we found that a great number of newly identified miRNAs were conserved in silkworm and Drosophila, and family alignment revealed that miRNA families might possess single nucleotide polymorphisms, miRNA gene clusters and possible functions of complement miRNA pairs are discussed.
文摘Silkworm powder containing 1-deoxynojirimycin (DNJ) has α-glucosidase inhibitory activity and is promising as a complementary and alternative medicine (CAM) agent in Japan. Silkworm powder produced in Korea was extracted with 75% ethanol. The extract was derivatized with 9-fluorenylmethyl chloroformate (FMOC-Cl), and DNJ-FMOC content was measured by HPLC. Then, alfa-glucosidase inhibition by silkworm and mulberry powder in pig liver crude enzyme was assayed using 4-nitrophenyl-alfa-D-glucopyranoside as a substrate. Silkworm powder DNJ content (0.39 to 0.58%) was higher than that in mulberry powder (0.08 to 0.12%). The alfa-glucosidase inhibitory activity of silkworm powder was more potent than that of mulberry leaves and green tea. Silkworm powder DNJ was stable upon heating to 121?C for up to 15 min.
文摘Peptide hydrolysates of silkworm pupae protein with molecular weight of less than 5000 Da were prepared by ultrafiltration. The extracted peptide hydrolysates of silkworm pupae protein had inhibitory action on angiotensin-I-converting enzyme activity in vitro. The hydrolysates were orally administered to spontaneously hypertensive rats (SHR) in one period and long-term (four weeks). The results showed that the systolic blood pressure (SBP) of the treatment groups decreased in a dose-related manner. After one oral administration of silkworm protein hydrolysates with doses of 60, 20 and 5 mg/kg, the SBP of SHR decreased by 21.5, 13.8, and 9.0 mmHg in 1.5 h. After four weeks of the treatment in 80 mg/kg, the SBP decreased by 25 mmHg, with the antihypertensive activity close to 4 mg/kg of captopril;the SBP of the 40 mg/kg dose group also decreased by 17.5 mmHg. The peptide hydrolysate did not affect the SBP in normal, non-hypertensive rats in one period and long-term treatments. The acute toxicity research showed that the peptide hydrolysates were safe and without side effects. This research would be helpful in exploring the silkworm protein peptides as functional components for the antihypertension treatment.
基金the National Natural Science Foundation of China (10402017,10732050,10525210,10121202)
文摘Most animals have the ability to adapt, to some extends and in different ways, the variation or disturbance of environment. In our experiments, we forced a silkworm caterpillar to spin two, three or four thin cocoons by taking it out from the cocoon being constructed. The mechanical properties of these cocoons were studied by static tensile tests and dynamic mechanical thermal analysis. Though external disturbances may cause the decrease in the total weight of silk spun by the silkworm, a gradual enhancement was interestingly found in the mechanical properties of these thin cocoons. Scanning electron microscopy observations of the fractured specimens of the cocoons showed that there exist several different energy dissipation mechanisms occurred simultaneously at macro-, meso-, and micro-scales, yielding a superior capacity of cocoons to adsorb the energy of possible attacks from the outside and to protect efficiently its pupa against damage. Through evolution of millions of years, therefore, the silkworm Bombyx mori seems to have gained the ability to adapt external disturbances and to redesign a new cocoon with optimized protective function when its first cocoon has been damaged for some reasons.
