Usage Chitosan

1 usage

1.1 agricultural , horticultural use

1.1.1 natural biocontrol , elicitor


1.2 filtration
1.3 winemaking , fungal source chitosan
1.4 biomedical uses
1.5 research
1.6 bioprinting
1.7 weight loss

usage
agricultural , horticultural use

the agricultural , horticultural uses chitosan, plant defense , yield increase, based on how glucosamine polymer influences biochemistry , molecular biology of plant cell. cellular targets plasma membrane , nuclear chromatin. subsequent changes occur in cell membranes, chromatin, dna, calcium, map kinase, oxidative burst, reactive oxygen species, callose pathogenesis-related (pr) genes , phytoalexins.

since 1986, united states environmental protection agency has regulated chitosan agricultural use.

natural biocontrol , elicitor

in agriculture, chitosan typically used natural seed treatment , plant growth enhancer, , ecologically friendly biopesticide substance boosts innate ability of plants defend against fungal infections. natural biocontrol active ingredients, chitin/chitosan, found in shells of crustaceans, such lobsters, crabs, , shrimp, , many other organisms, including insects , fungi. 1 of abundant biodegradable materials in world.

degraded molecules of chitin/chitosan exist in soil , water. chitosan applications plants , crops regulated epa, , usda national organic program regulates use on organic certified farms , crops. epa-approved, biodegradable chitosan products allowed use outdoors , indoors on plants , crops grown commercially , consumers.

the natural biocontrol ability of chitosan should not confused effects of fertilizers or pesticides upon plants or environment. chitosan active biopesticides represent new tier of cost-effective biological control of crops agriculture , horticulture. biocontrol mode of action of chitosan elicits natural innate defense responses within plant resist insects, pathogens, , soil-borne diseases when applied foliage or soil. chitosan increases photosynthesis, promotes , enhances plant growth, stimulates nutrient uptake, increases germination , sprouting, , boosts plant vigor. when used seed treatment or seed coating on cotton, corn, seed potatoes, soybeans, sugar beets, tomatoes, wheat , many other seeds, elicits innate immunity response in developing roots destroys parasitic cyst nematodes without harming beneficial nematodes , organisms.

agricultural applications of chitosan can reduce environmental stress due drought , soil deficiencies, strengthen seed vitality, improve stand quality, increase yields, , reduce fruit decay of vegetables, fruits , citrus crops . horticultural application of chitosan increases blooms , extends life of cut flowers , christmas trees. forest service has conducted research on chitosan control pathogens in pine trees , increase resin pitch outflow resists pine beetle infestation.

chitosan has rich history of being researched applications in agriculture , horticulture dating 1980s. 1989, chitosan salt solutions applied crops improved freeze protection or crop seed seed priming. shortly thereafter, chitosan salt received first ever biopesticide label epa, followed other intellectual property applications.

chitosan has been used protect plants in space, well, exemplified nasa s experiment protect adzuki beans grown aboard space shuttle , mir space station in 1997 (see photo left). nasa results revealed chitosan induces increased growth (biomass) , pathogen resistance due elevated levels of β-(1→3)-glucanase enzymes within plant cells. nasa confirmed chitosan elicits same effect in plants on earth.

nontoxic, low molecular weight chitosan polymer solutions appear safe enough broad-spectrum agricultural , horticultural uses. in 2008, epa approved natural broad-spectrum elicitor status ultralow molecular active ingredient of 0.25% chitosan.

a natural chitosan elicitor solution agriculture , horticultural uses granted amended label foliar , irrigation applications epa in 2009. given low potential toxicity , abundance in natural environment, chitosan not harm people, pets, wildlife, or environment when used according label directions. forest service tested chitosan ecofriendly biopesticide prearm pine trees defend against mountain pine beetles.

filtration

chitosan can used in hydrology part of filtration process. chitosan causes fine sediment particles bind together, , subsequently removed sediment during sand filtration. removes heavy minerals, dyes, , oils water. additive in water filtration, chitosan combined sand filtration removes 99% of turbidity. chitosan among biological adsorbents used heavy metals removal without negative environmental impacts.

in combination bentonite, gelatin, silica gel, isinglass, or other fining agents, used clarify wine, mead, , beer. added late in brewing process, chitosan improves flocculation, , removes yeast cells, fruit particles, , other detritus cause hazy wine.

winemaking , fungal source chitosan

chitosan has long history use fining agent in winemaking. fungal source chitosan has shown increase in settling activity, reduction of oxidized polyphenolics in juice , wine, chelation , removal of copper (post-racking) , control of spoilage yeast brettanomyces. these products , uses approved european use eu , oiv standards.

biomedical uses

chitosan s properties allow rapidly clot blood, , has gained approval in united states , europe use in bandages , other hemostatic agents. chitosan hemostatic products have been shown in testing u.s. marine corps stop bleeding , reduce blood loss, , result in 100% survival of otherwise lethal arterial wounds in swine. chitosan hemostatic products reduce blood loss in comparison gauze dressings , increase patient survival. chitosan hemostatic products have been sold u.s. army , used uk military. both , uk have used bandages on battlefields of iraq , afghanistan. chitosan hypoallergenic , has natural antibacterial properties, further support use in field bandages. chitosan s hemostatic properties allow reduce pain blocking nerve endings.

chitosan hemostatic agents chitosan salts made mixing chitosan organic acid (such succinic or lactic acid). hemostatic agent works interaction between cell membrane of erythrocytes (negative charge) , protonated chitosan (positive charge) leading involvement of platelets , rapid thrombus formation. chitosan salts can mixed other materials make them more absorbent (such mixing alginate), or vary rate of solubility , bioabsorbability of chitosan salt. chitosan salts biocompatible , biodegradable making them useful absorbable haemostats. protonated chitosan broken down lysozyme in body glucosamine , conjugate base of acid (such lactate or succinate), substances naturally found in body. chitosan salt may placed on absorbable backing. absorbable backing may synthetic (for instance made existing absorbable suture materials e.g. tephaflex polymer) or natural (e.g. cellulose or gelled/solidified honey). in addition salts, hydrogel-based chitosan bandages have been developed treat burn wounds. burns similar other wounds, problematic because associated membrane destabilization, energy depletion, , hypoxia, of can cause severe tissue necrosis if not treated or enough. chitosan-gelation bandages using nanofibrin have been shown more durable ointments, while still allowing gas exchange @ cell surface.

chitosan s properties allow used in transdermal drug delivery; mucoadhesive in nature, reactive (so can produced in many different forms), , importantly, has positive charge under acidic conditions. positive charge comes protonation of free amino groups. lack of positive charge means chitosan insoluble in neutral , basic environments. however, in acidic environments, protonation of amino groups leads increase in solubility. implications of important biomedical applications. molecule maintain structure in neutral environment, solubilize , degrade in acidic environment. means chitosan can used transport drug acidic environment, chitosan packaging degrade, releasing drug desired environment. 1 example of drug delivery has been transport of insulin.

chitosan can combined other materials. example, composite hydroxyapatite effective temporary post-operation bone filler, gradually biodegraded , replaced native bone tissue.

research

chitosan used in development of nanomaterials, bioadhesives, , edible coatings.

bioprinting

large three-dimensional functional objects made chitosan.

bioinspired materials, manufacturing concept inspired natural nacre, shrimp carapace or insect cuticles, has led development of bioprinting methods manufacture large scale consumer objects using chitosan. method based on replicating molecular arrangement of chitosan natural materials fabrication methods, such injection molding or mold casting. once discarded, chitosan-constructed objects biodegradable , non-toxic. method used engineer , bioprint human organs or tissues.

pigmented chitosan objects can recycled, option of reintroducing or discarding dye @ each recycling step, enabling reuse of polymer independently of colorants. unlike other plant-based bioplastics (e.g. cellulose, starch), main natural sources of chitosan marine environments , not compete land or other human resources.

film made of shrilk bioplastic

in 2011 scientists harvard created material called shrilk made sequential deposition of fibroin extracted silk, , chitosan extracted shrimp shells. design mimics layered structure of insect endocuticle similar components. result composite twice strength of stronger component (i.e.chitosan) , ten times strength of both components blend.

weight loss

chitosan marketed in tablet form fat binder . cochrane meta-analysis evaluated clinical trials performed dietary chitosan on minimum of 4 weeks found higher quality trials indicated no significant effect of chitosan , no clinical justification advising overweight people take chitosan supplements.

the u.s. food , drug administration (fda) issued warning letters supplement retailers made inappropriate claims supposed health benefits of using chitosan. chitosan has been studied potential increase gastrointestinal lumen viscosity , retard emptying of stomach, creating sense of satiety associated inhibiting absorption of dietary lipids.