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... The effect of chitosan on calcium (⁴⁷Ca) metabolism was investigated in rats. The whole-body retention of ⁴⁷Ca by rats fed on a 5% chitosan diet was significantly decreased when compared with that of rats fed on a cellulose diet, but showed no significant difference from that of rats fed on a fiber-free diet. Although there was no significant difference in the fecal excretion of ⁴⁷Ca between the c ...
plant products; food processing; food contamination; yeasts; chitosan; ripening; postharvest diseases; patents; USDA; antifungal properties; United States
Abstract:
... A coating for harvested agricultural commodities which delays ripening and controls decay is described. The coating comprises a modified chitosan matrix containing a yeast antagonistic to postharvest pathogens. The modified chitosan may be carboxymethylchitosan or glycolchitosan. The combined fungicidal activities of the modified chitosan and the antagonistic yeast make this formulation an attract ...
... A well-defined X-ray fiber pattern of chitosan acetate was obtained by immersing a tendon chitosan, prepared from a crab tendon chitin by a solid-state N-deacetylation, in an aqueous acetic acid-isopropanol solution at 110°C. This pattern was very similar to that of chitosan salts with some inorganic acids, such as HF, HCl, and H₂SO₄, in which chitosan chains form an 8/5 helix, indicating that chi ...
... We used differential display to identify chitosan responsive cDNAs in slash pine cell cultures. Two clones that showed increased mRNA abundance had sequence similarity to genes with roles in major plant defense responses, clone 18 to cinnamic acid 4-hydroxylase, and clone 30 to chitinase. ...
... 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/ ...
... Antimicrobial activity of irradiated chitosan was studied against Escherichia coli B/r. Irradiation of chitosan at 100 kGy under dry conditions was effective in increasing the activity, and inhibited the growth of E coli completely. The molecular weight of chitosan significantly decreased with the increase in irradiation dose, whereas the relative surface charge of chitosan was decreased only 3% b ...
... In response to wounding, a 48-kDa myelin basic protein (MBP) kinase is activated within 2 min, both locally and systemically, in leaves of young tomato plants. The activating signal is able to pass through a steam girdle on the stem, indicating that it moves through the xylem and does not require intact phloem tissue. A 48-kDa MBP kinase is also activated by the 18-amino acid polypeptide systemin, ...
... Hairy root cultures of Trigonella foenum-graecum L. were established with Agrobacterium rhizogenes strain A4. The hairy roots produce diosgenin, an important spirostanol for the semi-synthesis of steroid hormones. Fourteen different liquid media were investigated. The fastest growth was obtained in McCown's woody plant (WP) medium supplemented with 3% sucrose; the highest diosgenin content was obs ...
Enterobacter; Salvia hispanica; ammonium sulfate; biotechnology; calcium; carboxymethylcellulose; chitin; chitinase; chitosan; culture filtrates; fractionation; gel chromatography; isoelectric point; molecular weight; pH; polyacrylamide gel electrophoresis; temperature
Abstract:
... Entevobacter sp. G-1 which produces chitinolytic and chitosanolytic enzymes, was previously isolated in our laboratory. One major chitinase, designated ChiA, was purified 42.9-fold from a culture filtrate of Entevobacter sp. G-L To purify the chitinase, ammonium sulfate fractionation, DEAE-Sephadex A-50 column chromatography, and gel filtration on Sephadex G-100 column chromatography were used. Th ...
... Whole and headless shrimp (Pandalus borealis) were dipped in various concentrations of chitosan solution and stored for 20 days at 4-7 degrees C. The effects of chitosan on microbial proliferation, total volatile bases, nucleotide breakdown, and blackspot formation were monitored over this period. Chitosan showed strong antimicrobial properties inhibiting several microorganisms at concentrations r ...