Silkworms and spiders are capable of generating fibers that are both highly durable and elastic in a short span of time,using a silk solution stored within their bodies at room temperature and normal atmospheric press...Silkworms and spiders are capable of generating fibers that are both highly durable and elastic in a short span of time,using a silk solution stored within their bodies at room temperature and normal atmospheric pressure.The dragline silk fiber,which is essentially a spider's lifeline,surpasses the strength of a steel wire of equivalent thickness.Regrettably,humans have yet to replicate this process to produce fibers with similar high strength and elasticity in an eco-friendly manner.Therefore,it is of utmost importance to thoroughly comprehend the extraordinary structure and fibrillation mechanism of silk,and leverage this understanding in the manufacturing of high-strength,high-elasticity fibers.This review will delve into the recent progress in comprehending the structure of silks derived from silkworms and spiders,emphasizing the distinctive attributes of solidstate NMR.展开更多
The posterior silk gland (PSG) of silkworm is an important organ where fibroin is synthesized and secreted exclusively. Because fibroin constitutes 75-80% of the silk filament, the mechanism governing fibroin secret...The posterior silk gland (PSG) of silkworm is an important organ where fibroin is synthesized and secreted exclusively. Because fibroin constitutes 75-80% of the silk filament, the mechanism governing fibroin secretion, quality and yield of cocoon can be elucidated by the study on the PSG. Using two-dimensional gel electrophoresis (2-DE) and image analysis system, the changes in the protein composition in the PSG cell were investigated on the day 1 (D1) and day 4 (D4) in the 5th instar stage from five different strains of silkworm (Bombyx mori). While differences at protein level between days and strains were far less than those observed at the gene level using EST analysis. The change trends in protein composition from D1 to D4 were diverse among the different strains. The results suggest that the secretion of fibroin is regulated by multiple proteins. The site of regulation and the proteins responsible for the regulation vary with the strain, which leads to differences between strains in the capacity of fibroin secretion in the PSG cell.展开更多
Study of the morphology, aggregation structure and properties ofBombyx mori silk treated by low temperature oxygen plasma showed that slight flutes appeared on the surface of Bombyx mori silk fiber and that its surfac...Study of the morphology, aggregation structure and properties ofBombyx mori silk treated by low temperature oxygen plasma showed that slight flutes appeared on the surface of Bombyx mori silk fiber and that its surface structure changed after plasma treatment. The conformation also changed and crystalline degree decreased. The stannic filling rate of treated fiber was improved. Because of etching, the weight of the fiber decreased but the breaking strength changed little after short-time treatment.展开更多
Beyond the commonly known proteins built silk fibres--fibroin and sericin, there are almost 300 bioactive proteins in the silkworm haemolymph. The aim of this work was to present bioactive compounds obtained from the ...Beyond the commonly known proteins built silk fibres--fibroin and sericin, there are almost 300 bioactive proteins in the silkworm haemolymph. The aim of this work was to present bioactive compounds obtained from the silk fibre and isolated from the body of this insect, which may be used in medical and pharmacological applications. The most important are bioactive proteins. However, the juvenile stages of mulberry silkworm possess other very valuable active substances.展开更多
Beyond the production of silk thread, there are several studies showing that the silk is a great biomaterial for surgical sutures and grafts. This paper shows a new technique to produce silk thread changing the natura...Beyond the production of silk thread, there are several studies showing that the silk is a great biomaterial for surgical sutures and grafts. This paper shows a new technique to produce silk thread changing the natural cycle of silk production, which is the production of cocoons. This new method has the purpose of producing a silk fabric free of impurities, through flat surfaces. Six different surfaces were tested: Glass, Formica Surface, Steel and Zinc Sheets, Cotton tissue and Burlap Bag. The first five surfaces had not presented enough larvae alive for statistical analysis, because there were several damages in silkworms larvae that resulted in mortality and low silk production. On the other hand, the burlap bag surface presented good results for web construction by biospinning and its use was indicated for silk industry focused on biomaterials. The present study suggested the potential of naturally biospun web, using Bombyx mori, to develop a new technique to produce silk thread matrices that will have several applications at the industry and production of biomedical materials.展开更多
基金support by a JSPS KAKENHI,Grant-in-Aid for Scientific Research(C),Grant Number JP19K05609.
文摘Silkworms and spiders are capable of generating fibers that are both highly durable and elastic in a short span of time,using a silk solution stored within their bodies at room temperature and normal atmospheric pressure.The dragline silk fiber,which is essentially a spider's lifeline,surpasses the strength of a steel wire of equivalent thickness.Regrettably,humans have yet to replicate this process to produce fibers with similar high strength and elasticity in an eco-friendly manner.Therefore,it is of utmost importance to thoroughly comprehend the extraordinary structure and fibrillation mechanism of silk,and leverage this understanding in the manufacturing of high-strength,high-elasticity fibers.This review will delve into the recent progress in comprehending the structure of silks derived from silkworms and spiders,emphasizing the distinctive attributes of solidstate NMR.
文摘The posterior silk gland (PSG) of silkworm is an important organ where fibroin is synthesized and secreted exclusively. Because fibroin constitutes 75-80% of the silk filament, the mechanism governing fibroin secretion, quality and yield of cocoon can be elucidated by the study on the PSG. Using two-dimensional gel electrophoresis (2-DE) and image analysis system, the changes in the protein composition in the PSG cell were investigated on the day 1 (D1) and day 4 (D4) in the 5th instar stage from five different strains of silkworm (Bombyx mori). While differences at protein level between days and strains were far less than those observed at the gene level using EST analysis. The change trends in protein composition from D1 to D4 were diverse among the different strains. The results suggest that the secretion of fibroin is regulated by multiple proteins. The site of regulation and the proteins responsible for the regulation vary with the strain, which leads to differences between strains in the capacity of fibroin secretion in the PSG cell.
文摘Study of the morphology, aggregation structure and properties ofBombyx mori silk treated by low temperature oxygen plasma showed that slight flutes appeared on the surface of Bombyx mori silk fiber and that its surface structure changed after plasma treatment. The conformation also changed and crystalline degree decreased. The stannic filling rate of treated fiber was improved. Because of etching, the weight of the fiber decreased but the breaking strength changed little after short-time treatment.
文摘Beyond the commonly known proteins built silk fibres--fibroin and sericin, there are almost 300 bioactive proteins in the silkworm haemolymph. The aim of this work was to present bioactive compounds obtained from the silk fibre and isolated from the body of this insect, which may be used in medical and pharmacological applications. The most important are bioactive proteins. However, the juvenile stages of mulberry silkworm possess other very valuable active substances.
文摘Beyond the production of silk thread, there are several studies showing that the silk is a great biomaterial for surgical sutures and grafts. This paper shows a new technique to produce silk thread changing the natural cycle of silk production, which is the production of cocoons. This new method has the purpose of producing a silk fabric free of impurities, through flat surfaces. Six different surfaces were tested: Glass, Formica Surface, Steel and Zinc Sheets, Cotton tissue and Burlap Bag. The first five surfaces had not presented enough larvae alive for statistical analysis, because there were several damages in silkworms larvae that resulted in mortality and low silk production. On the other hand, the burlap bag surface presented good results for web construction by biospinning and its use was indicated for silk industry focused on biomaterials. The present study suggested the potential of naturally biospun web, using Bombyx mori, to develop a new technique to produce silk thread matrices that will have several applications at the industry and production of biomedical materials.