Cocoon silk, Bombyx mori

Iizuka, E. (1965). Degree of crystallinity and modulus relationships of silk thread from cocoons of Bombyx Mori and other moths. Biorheology 3, 1-8. 

Silk. Silk, the only natural fiber that comes in filament form, has been and still is one of the most appreciated and valued textile fibers. Silk filaments are secreted by the larvae of several types of silk moths to make their cocoons. Most silk is derived, however, from the larvae of the Bombyx mori moth, which has been widely cultivated in China for over 5000 years. Fragments of silk fabric dated to the late fourth millennium b.c.e. were found at Qianshanyang, in the province of Zhejiang, in China. There are, however, even earlier indications of the use of silk silk remains were found together with an eleventh-century b.c.e. mummy in Egypt, probably also providing evidence of ancient trading routes between the Far and Middle East. 

The larvae of Bombyx mori, the cultivated moth from which most silk has long been and still is made, feed on leaves of mulberry trees. In addition to cultivated silk, small quantities of "wild silk," also known as nonmulberry silk, have been derived in many parts of the world from the cocoons of moths other than Bombyx mori. Table 90 lists wild silks and the insect species that produce them (Peigler 1993 Jolly et al. 1979). 

Finally, as in macro-Raman experiments, orientation-insensitive spectra can also be calculated for spectromicroscopy. A method has been developed recently for uniaxially oriented systems and successfully tested on high-density PE rods stretched to a draw ratio of 13 and on Bombyx mori cocoon silk fibers [65]. This method has been theoretically expanded to biaxial samples using the K2 Raman invariant and has proved to be useful to determine the molecular conformation in various polymer thin films [58]. 

Silk, used for sutures, is obtained from the cocoon of the silk worm, Bombyx mori. Tension force is gradually lost until tissue encapsulation occurs. Tissue reactivity may be moderate because silk is a protein and its interaction with the body is not benign. It is classified as nonabsorbent because it retains much of its strength for more than 2 months and 50% to half a year, but loses most of its strength after 2 years. While stronger than cotton. 

Natural Silks. Many lepidopterous insects secrete from special glands a liquid which becomes solid in the air in the form of filaments destined for the construction of the cocoons in which the insects pass one stage of their existence. Ordinary silk is derived from Bombyx mori, and wild silk from other insects (Antheraea myliUa, A. Yama-mai), which live wild particularly in India, China and Japan. 

The silk from the cocoon of the mulberry silk spinner caterpillar [Bombyx mori) has been the most important source of natural silk for textiles for more than 5000 years. The cocoons consist of about 80% silk fiber and 20% glue. After immersion in hot water to soften the glue, the cocoons are treated with mechanical brushes that unwind the fibers. 

Silk fabric and thread are derived from the cocoons that some insects make as part of their metamorphosis from caterpillar to butterfly or moth. Most commercial silk is created by Bombyx mori, a small moth that was originally native to Asia. These animals no longer live in the wild, and in cultured populations they have lost their ability to fly. 

Silk is the only natural fibre which exists as a continuous filament. Each Bombyx mori cocoon can yield up to 1600 meters of filament. These can be easily joined together using the adhesive qualities of seriein to form a theoretically endless filament. 

There are all sorts of silk that are found in nature. The stuff that is usually found in textiles comes from silkworms (Bombyx mori). They are not really worms, but the larvae of moths. They emerge from very small eggs with an incredible lust for mulberry leaves, which they consume until they are ready to. pupate and weave a cocoon around themselves. Unlike spiders, which spin silk from their rear end, silkworm silk is actually hardened saliva, which comes out of the mouth. The larva has a small spinneret on its lip, through which the silk emerges. The cocoon is formed from a single strand of silk that... 

Silk is a fibrous protein produced by several insect species. Commercially, silk is produced from the cocoon stage larvae of the moth caterpillar Bombyx mori, as it has been, in China, for some 4500 years. A single cocoon produces a continuous thread up to 1 km in length, and the protein fibroin contains large amounts of glycine, alanine, tyrosine, proline and serine The peptide chains are arranged in anti-parallel P-sheets which make up the hierarchical structure of the crystalline silk fibres. A number of spiders also produce silk webs, although the fibroin structure is rather different to that from silk worms. 

Silk is a continuous protein niament spun by the silkworm to form its cocoon. The principle species used in commercial production is the mulberry silkworm, which is the larva of the silk moth, Bombyx mori. It belongs to the order Lepidoptera. 

The best-known wild silk is tussur, produced by Antheraeapernyiwhrch thrives on a diet of oak leaves and is found in China. I he worm is about 5 J in. long when mature and makes a compact cocoon which has a brownish colour. Spinning tends to be intermittent so that the filament is more broken than that of Bombyx mori, and for this reason it is more suitable for spun yarns. 

Along with cotton and wool, silk had long been one of the most useful fibers known to man. The material comes from the secretion of the mulberry leaf-feeding silkworm, Bombyx mori, a family of Lepidoptera that includes large moths and butterflies. The mature caterpillar produces a clear, viscous fluid called fibroin, which, in combination with another fluid called sericin, forms the solid filaments of silk that make up the cocoon. 

Over 90% of commercially produced silk is by the domesticated silkworm Bombyx mori. This is a monophagous insect with a diet that is restricted to the leaves of white mulberries, Moms alba and Moms indica. The production of silk requires the maintenance of mulberry plantations (moriculture), the rearing of silkworms to the cocoon spinning stage (sericulture) and finally the unravelling of cocoons (reeling). Each subsection of the production will be outlined below. 

Silks are fibrous proteins produced by spiders and insects such as the silk worm Bombyx mori). There are an astonishing variety in different mechanical properties and compositions of the different silks naturally produced. Many spiders and insects have a varied tool kit of task-specific silks with divergent mechanical properties [42 -49]. Those silks seem to have evolved to match a very particular need for the creature that produces them. Furthermore, although some spiders may use silk sparingly, most make rather elaborate nests, traps, and cocoons typically using more than one type of finely timed and speciaUzed silk. Those different silks are... 

Enseal yourself into and fly out of the cocoon. The three stages of insect metamorphosis are pro-nymph, nymph and adult within the cocoon larva, pupa and adult [1415]. The cocoon shell of the silk worm Bombyx mori is soaked with antibacterial proteins [1416]. During metamorphosis, apoptosis and autophagy... 

Pandiarajan J, Cathrin BP, Pratheep T, Krishnan M. Defense role of the cocoon in the silk worm Bombyx mori. Rapid Common Mass Spectiom. 2011 25 3203-6. 

Silks are protein-based fibers produced by several arthropods, most notably silkworms and spiders. Silkworms produce silk to form cocoons within which they metamorphosize into moths. The 5000-year-old sericulture industry has domesticated the Bombyx mori silkworm and has perfected the art of unreeling these cocoons into their single-fiber components to be woven into fabrics. These silk fibers are fine and lustrous, giving them compelling textile properties. Wild silkworms such as Antheraea paphia still exist and produce silks with different properties (e.g., crystallinity, aoss-sectional shape, color, dyeability) ... 

Silk filaments obtained from the cocoon of the silkworm (Bombyx mori) have been used for textile production since sericulture was originally developed in China many centuries ago. And since braided silk filaments have been used as surgical sutures for several decades, silk is recognized as a biocompatible and cytocompatible biomaterial. When winding their cocoons the silkworm... 

Lupeol a pentacyclic, triterpene alcohol, M, 426.73, m.p. 215°C, [al + 27.2 (c = 4.8 in CHa,). L. has a Sa-lnpane ring system. It occurs free, esteified and as the aglycon of triterpene Saponins (see) in many plants. It has been found, e.g. in the latex if Ficus spp, in the seed coats of the yellow lupin Lupinus lu-teus) and in the leaves of mistletoe. It has also been detected in the cocoons of the silk-worm, Bombyx mori. 

Jiang, P., Liu, H., Wang, C., Wu, L., Huang, J., Guo, C., 2006. Tensile behavior and morphology of differently degummed silkworm Bombyx mori) cocoon silk fibres. Materials Letters 60 (7), 919-925. 

Wen, H., Lan, X., Zhang, Y., Zhao, T., Wang, Y., Kajiura, Z., Nakagaki, M., 2010. Transgenic silkworms Bombyx mori) produce recombinant spider draghne silk in cocoons. Molecular Biology Reports 37 (4), 1815-1821. 

Silk is an interesting biomateiial that has been used since ancient times. It is a protein polymer (consisting of various amino acids) that is spun into fibers by insects like the silkworm, spider, scorpion, mites, and flies. Depending on the source and the arrangement of amino acids, there are a variety of silks, each having specific properties. Some evolutionary advanced species of insects are capable of spinning as many as nine or more varieties of silk for different purposes such as cocoon construction, lines for prey capture, safety lines or draglines, web construction, and adhesion [29]. The most widely characterized silks include those from the domesticated silkworm (Bombyx mori) and from spiders (Nephila clav-ipes and Araneus diadematus). 

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