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... A glycopeptide elicitor prepared from germ tubes of the rust fungus Puccinia graminis Pers. f. sp. tritici Erikss. & Henn (Pgt),as well as chitin oligosaccharides, chitosan, and methyl jasmonate (MJ) stimulated lipoxygenase (LOX) activity (E.C. 1.13.11.12) in wheat (Triticum aestivum) leaves. Immunoblot analysis using anti-LOX antibodies revealed the induction of 92- and 103-kD LOX species after P ...
... When a series of chitin oligosaccharides was added into a rice suspension culture, N-acetylchito- hexaose, N-acetylchitopentaose, and N-acetylchitotetraose caused an increase in extracellular chitinase activity, mainly due to induction of a class III chitinase. In the case of N-acetylchitohexaose, a substantial increase in the chitinase activity was observed at a concentration higher than 0.01 μg/ ...
... N-acetylchitooligosaccharides (fragments of chitin) elicit defense responses, including phytoalexin production, in suspension-cultured rice cells. They induced rapid and transient membrane depolarization accompanied by a transient increase in net Cl- -efflux. The membrane depolarization was not affected by anaerobiosis or azide, suggesting that the major part of the depolarization was mediated by ...
... Chitin synthase (EC 2.4.1.16) is a crucial enzyme responsible for chitin biosynthesis in all chitin-containing organisms. This paper reports a complete cDNA encoding chitin synthase 1 (AqCHS1), change of AqCHS1 mRNA level in response to diflubenzuron exposure, and concentration-dependent effect of diflubenzuron on chitin synthesis in the common malaria mosquito (Anopheles quadrimaculatus). The cDN ...
eclosion; Anopheles quadrimaculatus; insect growth; chemical composition; diflubenzuron; pupae; dose response; body weight; nikkomycins; mosquito control; toxicity; mortality; chitin; larvae
Abstract:
... Toxicities of three chitin synthesis inhibitors (diflubenzuron, nikkomycin Z and polyoxin D) were evaluated using second instars of the common malaria mosquito, Anopheles quadrimaculatus Say (Diptera: Culicidae). Neither nikkomycin Z nor polyoxin D at 50 μg/liter caused significant larval mortality, although they reduced the body weight of the survivors by 20.5 and 33.8%, respectively, in 48 h. In ...
... BACKGROUND: Previous studies showed that mammalian galectin-1 (GAL1) could interact with chitosan or chitin, one component of the peritrophic membrane (PM). This finding suggests that the PM could be a target of GAL1, which prompted the authors to explore the effect of GAL1 on larval growth and its potential mechanism.RESULTS: The development of Plutella xylostella (L.) larvae was significantly di ...
... Lectins have demonstrated significant levels of protection against different pests when expressed in transgenic plants. The effects of the coagulant Moringa oleifera lectin (cMoL) on moth flour (Anagasta kuehniella) were tested by incorporating the protein in an artificial diet at levels of 0.5%, 1% and 2% (w/w), respectively. cMoL showed a dose-dependent effect on average larval weight and a seri ...
... The effects of sublethal concentrations 0.1, 0.5, and 1.2 micrograms mL-1 of the chitin synthesis inhibitor, hexaflumuron, on larval growth and development, the count and proportion of hemocytes, and carbohydrate content (trehalose and glyceride) in hemolymph were investigated in the cutworm, Spodoptera litura (Fabricious) (Lepidoptera: Noctuidae). When 3rd instar larvae were subjected to the subl ...
... Chitin has been chemically extracted from the Egyptian shrimp shell waste. The obtained chitin was transformed into the more soluble chitosan. Chitin and chitosan were characterized using Fourier-transform infrared spectroscopy and proton nuclear magnetic resonance spectrometry. These products were also characterized by their nematicidal potential against the root-knot nematode, Meloidogyne incogn ...
Mariana C.C. Silva; Lucimeire A. Santana; Reinhard Mentele; Rodrigo S. Ferreira; Antônio de Miranda; Rosemeire A. Silva-Lucca; Misako U. Sampaio; Maria T.S. Correia; Maria L.V. Oliva
... A new lectin, BfL, was purified from Bauhinia forficata seeds by ammonium sulfate fractionation, DEAE-Sephadex ion exchange chromatography, Sepharose-4B and chitin affinity chromatographies and Superdex 75 size exclusion chromatography. The molecular homogeneity and purity of BfL were assessed by reversed-phase HPLC. BfL appeared as a single band of approximately 27.0kDa on SDS-PAGE under non-redu ...
... A novel chitin derivative with an alternating N-l-cysteinyl group was successfully prepared. The precursor chitin derivative with an alternating N-l-thioprolinyl group could be obtained via chitinase-catalyzed polymerization of the N′-l-thioprolinyl chitobiose oxazoline derivative as a transition state analog substrate monomer under weak alkaline conditions. Conversion of the l-thioprolinyl group ...
Bartel Vanholme; Ruben Vanholme; Halbay Turumtay; Geert Goeminne; Igor Cesarino; Florence Goubet; Kris Morreel; Jorge Rencoret; Vincent Bulone; Cortwa Hooijmaijers; Riet De Rycke; Godelieve Gheysen; John Ralph; Marc De Block; Frank Meulewaeter; Wout Boerjan
... Crab shells waste were fermented using six protease-producing Bacillus species (Bacillus subtilis A26, Bacillus mojavensis A21, Bacillus pumilus A1, Bacillus amyloliquefaciens An6, Bacillus licheniformis NH1 and Bacillus cereus BG1) for the production of chitin and fermented-crab supernatants (FCSs). In medium containing only crab shells, the highest demineralization DM was obtained with B. lichen ...
... Immunostimulants increase the immunocompetency and disease resistance of fish by enhancing immune responses. This study determined the in vitro and dietary effects of chitin on immune responses of catla, Catla catla. Catla head‐kidney leukocytes were cultured in complete RPMI‐1640 medium containing 0.01, 0.1, and 1.0 mg/mL of chitin. Leucocyte viability and different cellular immune responses, nam ...
... Thecosome pteropods, a group of calcifying holoplanktonic mollusks, have recently become a research focus due to their potential sensitivity to increased levels of anthropogenic dissolved CO2 in seawater and the accompanying ocean acidification. Some populations, however, already experience high CO2 in their natural distribution during diel vertical migrations. To achieve a better understanding of ...
... Chitin was recovered through enzymatic deproteinization of the Norway lobster (Nephrops norvegicus) processing by-products. The obtained chitin was characterized and converted into chitosan by N-deacetylation, the acid-soluble form of chitin. Chitosan samples were then characterized by Fourier transform infrared spectroscopy (FTIR) and 13 Cross polarization magic angle spinning nuclear magnetic re ...
... The volatile oil (1.12%) from the Z. zerumbet rhizomes were extracted using Clevenger’s distillation. The GC and GC-MS profile of the Z. zerumbet volatiles revealed several components of which Zerumbone was the principal compound (49.8%) followed by α-Caryophyllene (20.1%) and trace of other compounds. The antifungal property of volatiles was studied against Aspergillus flavus and Aspergillus ochr ...
... To accomplish consistent, long-term, integrated management (IPM) of the Colorado potato beetle, Leptinotarsa decemlineata (Say), research assessing the potential of novel, IPM-compatible insecticides is essential. Novaluron is a potent benzoylurea insecticide. In the present paper, we found that novaluron ingestion by the fourth-instar larvae inhibited foliage consumption, reduced larval fresh wei ...
... AIMS: This study investigates the effect that aqueous extracts of Tulbaghia violacea Harv. harbouring plant saponins, phenolics and tannins have on Aspergillus flavus β‐(1,3) glucan and chitin synthesis. METHODS AND RESULTS: Aspergillus flavus was treated with various subinhibitory concentrations of an aqueous T. violacea plant extract and the β‐(1,3) glucan and chitin content was determined toget ...
... An end-modified β-d-galactosyl chitotetraose derivative [44-O-β-d-galactosyl-β-tri-N-acetylchitotriosyl 2-acetamide-2,3-dideoxy-glucopyranose; Gal(GlcN)3D] was designed and synthesized from chitin tetrasaccharide. The derivative was chemically modified by dehydration of the reducing end GlcN and enzymatic addition of a Gal group to the non-reducing end GlcN. Hydrolysis of Gal(GlcN)3D and related c ...
... Salinivibrio genus is commonly found in salted seafood products. In this study, chitinase produced by Salinivibrio sp. BAO‐1801 isolated from salted fermented shrimp was purified and subsequently characterized. The molecular weight of BAO‐1801 chitinase was approximately 94.2 kDa by SDS–PAGE analysis. It was classified as a chitinase C based on homology analysis of its N‐terminal amino acid residu ...
... This study aimed to evaluate efficiency of adsorption of chitins of marine and freshwater shrimps, three commercial chitosan and chitosan produced in laboratory in the removal of total ammonia synthetic effluents with different initial concentrations of ammonia and natural aquaculture effluents. The adsorbents were characterized in relation to degree of deacetylation, specific surface area and por ...
... The potential of teflubenzuron was assessed in a series of laboratory studies in order to achieve consistent, long-term, integrated management of the Colorado potato beetle, Leptinotarsa decemlineata (Say). Teflubenzuron exhibited excellent stomach toxicity to the larvae. Its larvicidal activity was comparable with those of cyhalothrin, chlorantraniliprole and spinosad. Moreover, the teflubenzuron ...
... Exo-β-N-acetylglucosaminidases (GlcNAcases) are hydrolytic enzymes involved in the metabolism of chitin in bacteria and in eukaryotic glycosphingolipid metabolism, with genetic defects in human GlcNAcases (HexA and HexB) resulting in Tay-Sachs and Sandhoff diseases, respectively. Here, we determined the effects of three known inhibitors of exo-β-N-acetylglucosaminidases (PUGNAc, NHAcCAS and NHAcDN ...
... Excessive blue light light-emitting diode (LED) exposure and consequent oxidative stress causes damage to retinal pigment epithelial (RPE) cells. Chitosan oligosaccharides (COSs) are the hydrolyzed products of chitin, which is abundant in the exoskeleton of crustaceans and cell walls of fungi. We investigated the protective effect of COSs on blue light LED-induced RPE cell damage. These cells were ...
... Some filamentous fungi are plant pathogens that cause serious economic losses in foodstuffs and agricultural commodities. In the present study, the antifungal effects of culture filtrates of soil strains of Bacillus subtilis and Bacillus amyloliquefaciens were studied against some common field-pathogenic fungi with special reference to the possible mode of actions against Aspergillus parasiticus N ...
... Triflumuron (TFM) is one of the most widely used insecticides over the world. It is a benzoylphenyl urea that belongs to the class of insect growth regulators. This insecticide acts by inhibiting insect’s chitin synthesis and by consequences, making insect more susceptible to pathogens and malformations. TFM effects have been reported in mammalians and crops. However, studies that reveal its toxic ...
... The biopolymer chitosan is a derivative of chitin, which can promote plant growth and protect plants from phytopathogens. This study aimed to evaluate the efficacy of chitosan as a biostimulant and a biorational agent to protect cucumber plants from damping-off disease caused by Phytophthora capsici. Cucumber seeds were treated with a range of chitosan concentrations, viz. 0, 125, 250, and 500 ppm ...
... As the main component of the fungal cell wall, chitin has been regarded as an optimal molecular target for the biocontrol of plant-pathogenic fungi. In this study, the chitin hydrolase CcCti1, which belongs to the glycoside hydrolase family 18 (GH 18) and exhibits potential antifungal activity, was identified from Corallococcus sp. EGB. CcCti1 lacks a fibronectin type-III (FN3) domain that is pres ...
... A chitinase was purified from naked oat (Avena chinensis) seeds using simple chromatographic techniques. Its molecular weight and isoelectric point were determined as 35 kDa and 8.9, respectively. The purified chitinase exhibited specific activity of 3.6 U/mg and 15.6% yield using colloidal chitin as substrate. Partial amino acid sequence analysis and homology search indicated that it probably bel ...
... This study assessed the effects of diets supplemented with different types of chitin hydrolysate on larval growth of the Japanese eel Anguilla japonica. Larvae were reared for 26 days on artificial diets containing 2% of purified monomeric N-acetylglucosamine (NAG1), a mixture of mono-, di- and trimers (NAG3), a mixture of mono-, di-, tri-, tetra-, penta- and hexamers (NAG6), or a control diet. Th ...
... In insects, nuclear receptors (NRs) including EcR (NR1H1), USP (NR2B4), E75 (NR1D3), HR3 (NR1F), HR4 (NR6) and FTZ-F1 (NR5A3) mediate the 20-hydroxyecdysone (20E) signaling cascade to play a critical role during larval metamorphosis. In this present paper, we focused on hormone receptor 38 (HR38) in Leptinotarsa decemlineata, the only insect homolog of the NR4A subclass. RNA interference (RNAi) of ...
Fourier transform infrared spectroscopy; Streptomyces; anti-inflammatory activity; biodegradation; bioreactors; breast neoplasms; carbon; cell movement; cell proliferation; chitin; chitooligosaccharides; culture flasks; dose response; electrospray ionization mass spectrometry; enzymes; free radical scavengers; human diseases; metal ions; microorganisms; models; neoplasm cells; nitrogen; pH; salt concentration; surfactants
Abstract:
... The present study focuses on the preparation of N-acetyl chitooligosaccharides (N-AcCOS) by microbial degradation of colloidal chitin using novel Streptomyces chilikensis strain RC1830 instead of using chitinolytic enzymes extracted from microorganisms as reported earlier. Statistical optimization of the factors such as pH, media, carbon source, nitrogen source, salt concentration, surfactants and ...
... Frass, a by-product of the larval meal industry, is heterogeneous and includes larval excrement, exoskeleton sheds and residual feed ingredients along with abundant nutrients, chitin and beneficial microbes. The present study was performed to evaluate the changes in growth, feed utilization, body composition, hematology, serum chemistry, immune responses and disease resistance of hybrid tilapia, N ...
Agaricus bisporus; Danio rerio; adults; bone formation; bone morphogenetic proteins; cartilage; cell walls; chitin; dose response; fins; fish; glucosamine; hydrochloric acid; hydrolysis; larvae; models; osteoporosis; skeletal development
Abstract:
... Glucosamine hydrochloride (GAH), one of the most basic and important derivatives of chitin, is obtained by hydrolysis of chitin in concentrated hydrochloric acid. At present, little is known about how GAH functions in skeletal development. In this report, we demonstrate that GAH, extracted from the cell wall of Agaricus bisporus, acts in a dose-dependent manner to promote not only cartilage and bo ...
... o-Vanillin is a natural product that has been widely applied in the food and pharmaceutical industries. In this study, we determined that o-vanillin can strongly inhibit the growth of Aspergillus flavus mycelia. However, the inhibition mechanism of o-vanillin is still elusive. The ultrastructural morphology of mycelia was injured, and the cell walls were destroyed. The OH functional groups on cell ...
... Dry rot is a major disease of potato during storage, which is caused by several Fusarium species. Biological control based on natural bioactive compounds that inhibit tuber disease provides an attractive alternative because they are ecofriendly and low toxic. In this study, a monoterpene phenol thymol (2-isopropyl-5-methylphenol) was found to have an effective antifungal effect against Fusarium ox ...
... Hexabromocyclododecanes (HBCDs), widely used brominated flame retardants, easily accumulate in aquatic organisms such as Macrophthalmus japonicus crabs, which inhabit tidal flat sediments. To analyze the effects of HBCD exposure in chitin-formed exoskeleton, we investigated molecular responses of chitin-related genes as well as physical changes of the exoskeletal surface form as a new biological e ...
... BACKGROUND: Silencing specific genes in pests using RNA interference (RNAi) technology is a promising new pest‐control strategy. The Asian citrus psyllid, Diaphorina citri Kuwayama, is the most important citrus pest because it transmits Candidatus Liberibacter asiaticus, which causes huanglongbing. Chitin is essential for insect development, and enzymes in this pathway are attractive targets for p ...
... Plant-derived methyl benzoate (MB) is a scent and aroma released by many flowers and fruits. Recently, MB has emerged as an alternative pesticide to control insect pests. However, the molecular mechanisms of insects' responses to MB remain to be investigated. MB exhibited a dose-dependent toxicity to all the developmental stages of Tribolium castaneum (Herbst). Based on the PoloPlus analysis of th ...
... Straw return to soil is a global field practice for sequestering carbon (C) in agricultural ecosystems, and soil C mineralization depends on the soil microbial metabolic process. However, the variation patterns of microbial respiration (Rs) and associated mechanisms under long-term straw input at different levels remain unclear. Here, this study investigated the changes in Rs and microbial metabol ...