Biopolymers are natural polymers produced by the cells of living organisms. Like other polymers, biopolymers consist of monomeric units that are covalently bonded in chains to form larger molecules. There are three main classes of biopolymers, classified according to the monomers used and the structure of the biopolymer formed: polynucleotides, polypeptides, and polysaccharides. The Polynucleotides, RNA and DNA, are long polymers of nucleotides. Polypeptides include proteins and shorter polymers of amino acids; some major examples include collagen, actin, and fibrin. Polysaccharides are linear or branched chains of sugar carbohydrates; examples include starch, cellulose, and alginate. Other examples of biopolymers include natural rubbers, suberin and lignin, cutin and cutan, melanin, and polyhydroxyalkanoates (PHAs).
Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the cocoons of the larvae of the mulberry silkworm Bombyx mori reared in captivity (sericulture). The shimmering appearance of silk is due to the triangular prism-like structure of the silk fibre, which allows silk cloth to refract incoming light at different angles, thus producing different colors.
Bombyx mori, commonly known as the domestic silk moth, is a moth species belonging to the family Bombycidae. It is the closest relative of Bombyx mandarina, the wild silk moth. Silkworms are the larvae of silk moths. The silkworm is of particular economic value, being a primary producer of silk. The silkworm's preferred food are the leaves of white mulberry, though they may eat other species of mulberry, and even leaves of other plants like the osage orange. Domestic silk moths are entirely dependent on humans for reproduction, as a result of millennia of selective breeding. Wild silk moths, which are other species of Bombyx, are not as commercially viable in the production of silk.
Spider silk is a protein fibre or silk spun by spiders. Spiders use silk to make webs or other structures that function as adhesive traps to catch prey, to entangle and restrain prey before biting, to transmit tactile information, or as nests or cocoons to protect their offspring. They can use the silk to suspend themselves from height, to float through the air, or to glide away from predators. Most spiders vary the thickness and adhesiveness of their silk according to its use.
A byssus is a bundle of filaments secreted by many species of bivalve mollusc that function to attach the mollusc to a solid surface. Species from several families of clams have a byssus, including pen shells (Pinnidae), true mussels (Mytilidae), and Dreissenidae.
Sericulture, or silk farming, is the cultivation of silkworms to produce silk. Although there are several commercial species of silkworms, the caterpillar of the domestic silkmoth is the most widely used and intensively studied silkworm. This species of silkmoth is no longer found in the wild as they have been modified through selective breeding, rendering most flightless and without defense against predators. Silk is believed to have first been produced in China as early as the Neolithic period. Sericulture has become an important cottage industry in countries such as Brazil, China, France, India, Italy, Japan, Korea, Russia, and Thailand. Today, China and India are the two main producers, with more than 60% of the world's annual production.
Bombykol is a pheromone released by the female silkworm moth to attract mates. It is also the sex pheromone in the wild silk moth. Discovered by Adolf Butenandt in 1959, it was the first pheromone to be characterized chemically.
Bombyx mandarina, the wild silk moth, is a species of moth in the family Bombycidae. It is the closest relative of Bombyx mori, the domesticated silk moth. The silkworm is the larva or caterpillar of a silk moth. Unlike the domesticated relative which is unable to fly or indeed persist outside human care, the wild silk moth is a fairly ordinary lepidopteran. Its main difference from the domesticated taxon is the more slender body with well-developed wings in males, and the dull greyish-brown colour.
A dermal patch or skin patch is a medicated adhesive patch placed on human skin to deliver a medication into the skin. This is in contrast to a transdermal patch, which delivers the medication through the skin and into the bloodstream.
Wild silks have been known and used in many countries from early times, although the scale of production is far smaller than that from cultivated silkworms. Silk cocoons and nests often resemble paper or cloth, and their use has arisen independently in many societies.
Cocoonase is a trypsin-like proteolytic enzyme produced by silkworms as they near the final stages of their metamorphosis. It is produced by cells in the proboscis and exuded onto the galeae. Its function is to weaken the fibers of the cocoon, thereby facilitating the emergence of the adult insect.
Sericin is a protein created by Bombyx mori (silkworms) in the production of silk. Silk is a fibre produced by the silkworm in production of its cocoon. It consists mainly of two proteins, fibroin and sericin. Silk consists of 70–80% fibroin and 20–30% sericin; fibroin being the structural center of the silk, and sericin being the gum coating the fibres and allowing them to stick to each other.
Kraig Biocraft Laboratories, Inc. is an American biotechnology company headquartered in Ann Arbor, Michigan. It develops and manufactures recombinant spider silks and other high-performance polymers using spider silk gene sequences. Their most notable fiber is dragon silk which has been demonstrated to be tougher than many fibers used in bullet proof vests.
Moricin is a highly basic antibacterial peptide that was isolated from the silkworm Bombyx mori. It consists of a long alpha-helix with 8 turns from a 42 amino acid sequence over almost the entire protein. The amphipathic N-terminal segment of the alpha- helix is mainly responsible for the increase in permeability of the bacterial membrane which kills the bacteria. Moricin functions as an antibacterial peptide against Gram-positive and Gram-negative bacteria, with its main activity being towards Gram-positive bacteria.
Demineralizing has the potential to be used in the silk sector enabling wet reeling of Wild Silk moth cocoons by removing the mineral layer present in these cocoons. This technique is not like degumming where the gum of the fibroin fibres is removed what would lead to a tangled cocoon. With "demineralizing" the gum and structure of the cocoon is kept intact enabling the cocoons to be wet reeled. This could allow a new silk industry in areas which have not the conditions or infrastructure for raising the domesticated silk worm Bombyx mori, possibly generating a revolutionary new income stream.
A silk mill is a factory that makes silk for garments using a process called silk throwing. Traditionally, silk mills were concentrated in Japan, England, New Jersey, Pennsylvania, Italy and Switzerland.
Silk amino acid (SAAs) also known as Sericin is a natural water-soluble glycoprotein extracted from raw silk. It is used as an additive in skin and hair care products due to its high levels of serine which has excellent moisture preservation characteristics. As a water-based additive it is used to provide a protective barrier and silky feel to lotions, soaps, personal lubricants, hair and skincare products. Silk amino acids are produced by hydrolyzing silk proteins into smaller peptide chains, typically 18 to 19 amino acids in length. Silk amino acids have a lower molecular weight than silk protein powders and are moisturizing to skin and hair.
An aquamelt is a naturally hydrated polymeric material that is able to solidify at environmental temperatures through a controlled stress input.
Bidensovirus is a genus of single stranded DNA viruses that infect invertebrates. The species in this genus were originally classified in the family Parvoviridae but were moved to a new genus because of significant differences in the genomes.
Caddisfly silk is silk that is secreted by the silk glands of the caddisfly (Trichoptera), similar to Lepidoptera silkworms. The larvae use silk to hunt and defend themselves. The silk's underwater binding properties are a subject of ongoing scientific research.
