127959-06-2Relevant articles and documents
Simplified determination of the content and average degree of acetylation of chitin in crude black soldier fly larvae samples
D'Hondt, Els,Soetemans, Lise,Bastiaens, Leen,Maesen, Miranda,Jespers, Vincent,Van den Bosch, Bert,Voorspoels, Stefan,Elst, Kathy
, (2020)
Insects are considered a promising alternative protein source for food and feed, but contain significant amounts of chitin, often undesirable due to indigestibility, disagreeable texture and negative effect on nutrients intake. Fractionation strategies are thus increasingly being applied to isolate and valorize chitin separately. The analysis of chitin generally requires an intensive pretreatment to remove impurities, and derivatization to generate sufficient detector response. In this work, a liquid chromatography method, without pretreatment nor derivatization, was developed for the simultaneous determination of chitin content and degree of acetylation in non-purified samples of black soldier fly (BSF) larvae. The method is found to be more suitable, compared to traditional methods, for assessing high degrees of acetylation. For the first time, the degree of acetylation of BSF chitin (81 ± 2%) is reported. Additionally, the chitin content of BSF soft tissues is estimated at approximately 20% of the total chitin content (8.5 ± 0.1%).
Configuration of N-acetylneuraminic acid.
BRUG,PAERELS
, p. 1159 - 1160 (1958)
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Escherichia coli O106, a new member of a group of enteric bacteria sharing an O-polysaccharide backbone structure
Shashkov,Senchenkova,Naumenko,Kalinchuk,Perepelov,Knirel, Yu. A.
, p. 1538 - 1541 (2018)
O-Polysaccharides (O-antigens) of a number of genetically related Escherichia coli O-serogroups (O17, O44, O73, O77, and O106) and Salmonella enterica O:6,14 possess an identical main chain composed of d-GlcNAc and d-Man residues and differ from each other by the absence or presence of glucose side chains at various positions. Using two-dimensional NMR spectroscopy, we established the structure of the O-polysaccharide of E. coli O106 having two glucose side chains in a hexasaccharide repeating unit.
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Roseman,Ludowieg
, p. 301 (1954)
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Structure and antioxidant activity study of sulfated acetamido- polysaccharide from Radix Hedysari
Dang, Zilong,Feng, Demei,Liu, Xiaohua,Yang, Tao,Guo, Long,Liang, Jin,Liang, Jiandi,Hu, Fangdi,Cui, Fang,Feng, Shilan
, p. 20 - 32 (2013)
A new sulfated acetamido-heteropolysaccharide, HPS4-2A, was obtained by aqueous extraction followed by precipitation with ethanol and fractionation with DEAE column chromatography from Radix Hedysari. It was composed of rhamnose, arabinose, glucose, galactose and 2-acetamido-2-deoxy-D-galactose in the molar ratio of 10.09%:25.90%:25.90%:25.0%:12.30%. Elemental analysis indicated that HPS4-2A was a sulfated polysaccharide containing small amount of sulfate groups (1.87%). Partial acid hydrolysis, GC, GC-MS, 1D and 2D NMR spectroscopy analysis of the HPS4-2A revealed a predominance of glucose, galactose and 2-acetamido-2-deoxy-D-galactose linked in a highly-branched structure. Themolecular weight of HPS4-2Awas determined by HPSEC and HPSEC-MALLS. AFMstudy indicated that HPS4-2A took a highly branched conformation, which in consistent with the result studied by SEC-MALLS. Structural features of HPS4-2A were also investigated by SEM and TEM. Antioxidant assays demonstrated that HPS4-2A possessed of strong DPPH and hydroxyl radicals scavenging activities, suggesting that HPS4-2A could potentially be used as natural antioxidant.
Cytotoxic Oleanane-Type Saponins from the Leaves of Albizia anthelmintica Brongn.
Al-Sayed, Eman,Eldahshan, Omayma A.,Bahgat, Dina M.,Singab, Abdel Nasser B.
, p. 1666 - 1673 (2016)
Two new oleanane-type saponins: β-d-xylopyranosyl-(1 → 4)-6-deoxy-α-l-mannopyranosyl-(1 → 2)-1-O-{(3β)-28-oxo-3-[(2-O-β-d-xylopyranosyl-β-d-glucopyranosyl)oxy]olean-12-en-28-yl}-β-d-glucopyranose (1) and 1-O-[(3β)-28-oxo-3-{[β-d-xylopyranosyl-(1 → 2)-α-l-
Synthesis of N-acetyl-lactosamine via ozonolysis of a nitro derivative
Lattova, Erika,Petrus, Ladislav
, p. 289 - 294 (1992)
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Mutational analysis of amino acid residues involved in catalytic activity of a family 18 chitinase from tulip bulbs
Suzukawa, Keisuke,Yamagami, Takeshi,Ohnuma, Takayuki,Hirakawa, Hideki,Kuhara, Satoru,Aso, Yoichi,Ishiguro, Masatsune
, p. 341 - 346 (2003)
We expressed chitinase-1 (TBC-1) from tulip bulbs (Tulipa bakeri) in E. coli cells and used site-directed mutagenesis to identify amino acid residues essential for catalytic activity. Mutations at Glu-125 and Trp-251 completely abolished enzyme activity, and activity decreased with mutations at Asp-123 and Trp-172 when glycolchitin was the substrate. Activity changed with the mutations of Trp-251 to one of several amino acids with side-chains of little hydrophobicity, suggesting that hydrophobic interaction of Trp-251 is important for the activity. Molecular dynamics (MD) simulation analysis with hevamine as the model compound showed that the distance between Asp-123 and Glu-125 was extended by mutation of Trp-251. Kinetic studies of Trp-251-mutated chitinases confirmed these various phenomena. The results suggested that Glu-125 and Trp-251 are essential for enzyme activity and that Trp-251 had a direct role in ligand binding.
Cloning and expression of chitinase a from serratia marcescens for large-scale preparation of N,N-Diacetyl chitobiose
Wu, Yue-Jin,Cheng, Chih-Yu,Li, Yaw-Kuen
, p. 688 - 695 (2009)
The gene of Serratia marcescens chitinase A(chiA) was cloned by PCR. The complete gene was constructed into a pRSET vector and expressed in Escherichia coli. The recombinant enzyme was purified to > 90% homogeneity by hydrophobic interaction chromatograph
