200210
doi
10.5281/zenodo.200210
oai:zenodo.org:200210
user-ajnp
George Ndukwe
Department of Chemistry, Faculty of Science, Ahmadu Bello University, Zaria
Rachael Ayo
Samaru College of Agriculture, Division of Agricultural Colleges, Ahmadu Bello University, Zaria
Isolation and Characterisation of Some Microalgae Bioactive Molecules
Emeka Ugoala
Fisheries Products’ Development Programme, National Institute for Freshwater Fisheries Research, P.M.B. 6006, New Bussa 913003, Niger State
info:eu-repo/semantics/openAccess
Creative Commons Attribution 4.0 International
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Solid-state NMR, CP/MAS, Glycoamino acids, Carbohydrate, Chemical shift, Carbon resonance
<p>This study involved the isolation, structure elucidation, and biological screening of secondary metabolites in freshwater microalgae for bioactive and chemically novel compounds. Isolates were fractionated and purified from the methanol, ethyl acetate, dichloromethane, petroleum ether and aqueous extracts of microalgae via column chromatography technique over silica gel using a gradient mixture of solvents. The chemical structures of isolated compounds have been elucidated using Solid-state cross polarization (CP) and magic angle spinning (MAS) <sup>13</sup>C-NMR spectroscopic technique at spectrometer frequency at a field strength corresponding to 91.3695 MHz for <sup>13</sup>C and 363.331 MHz for <sup>1</sup>H. Of the nine compounds isolated, eight have a glycan skeleton with attached amino acids units. Two of the eight contain beta amino acids units. These are not very common metabolites but hold promise as drug leads. The elements of diversity in the isolates were the gluco and manno configurations of the pyranose ring, the α-configurations at the anomeric centre, and the positions of the carbohydrate and amino acid sectors in the ring. These molecules are not easily available through gene technology since they are post translational products resulting from the activity of glycosyl hydrolases and transferases. The chemical shifts were rationalized in terms of the number of sugar residues, the sugar ring structures, the positions and anomeric configurations of the inter-sugar linkages. Considering all the NMR data, it was concluded that the compounds were glycylglycylglycylglycine, α-D-glucopyranosyl-2-amino-4-methylpentanoic acid, α-D-glucopyranosyl-2-methylamino-4-methylpentanoic acid, α-D-glucopyranosyl-2-amino-4-methylpentanoate, α-D-glucopyranosyl-glycylglycine, α-D-glucopyranosyl-3-aminobutanoic acid, α-D-glucopyranosyl-2,4,7-triaminooctantrioic acid, α-D-mannopyranosyl-2-amino-3-methylbutanoic acid and α-D-mannopyranosyl-3-aminobutanoic acid.</p>
Zenodo
2016-12-11
info:eu-repo/semantics/article
689046
user-ajnp
1579541715.366937
831409
md5:fc010a089021194b811837536fa3e594
https://zenodo.org/records/200210/files/AJNP-2016-15.pdf
public
isVersionOf
doi
ALGERIAN JOURNAL OF NATURAL PRODUCTS
4
3
323 - 347
2016-12-11