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1.
In this paper the recent population changes of the Wild Boar in different European countries is analysed through the study of hunting statistics. A simultaneous increase in numbers is observed throughout the whole area during the period 1965–1975. From 1975 onwards the population stabilizes itself apart from in peripheral areas like Finland. Potentially favourable factors which play a part in this process are discussed and certain reproductive and dispersive characteristics which favour its invasive behaviour are discussed. 相似文献
2.
Complete acid hydrolysis of red algal galactans in the presence of borane - 4-methylmorpholine complex has been shown to prevent the acid degradation of 3,6-anhydrogalactose derivatives by their reduction to the corresponding 3,6-anhydro-galactitols, whereas all the other monosaccharides are liberated essentially in the non-reduced form; the reductive hydrolysis products may be determined quantitatively using gas-liquid chromatography (GLC). The method is recommended for preliminary characterization of the polysaccharide composition of red algal biomass. Partial acid hydrolysis of galactans in the presence of the same reducing agent gives rise to reduced oligosaccharides having terminal 3,6-anhydrogalactitol residues. Based on this reaction, the attribution of unknown galactans to the agar or carrageenan groups is possible by partial reductive hydrolysis of small samples of algal biomass with subsequent identification of agarobiitol or carrabiitol acetates by GLC. Sulfate groups are substantially retained under partial reductive hydrolysis conditions; the isolation by liquid chromatography and elucidation of structures of reduced sulfated oligosaccharides may be of great value for the structural analysis of complex red algal galactans. 相似文献
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4.
A. I. Usov G. P. Smirnova Z. Kamenarska St. Dimitrova-Konaklieva K. L. Stefanov S. S. Popov 《Russian Journal of Bioorganic Chemistry》2004,30(2):161-167
GC-MS of trimethylsilyl derivatives of the compounds present in the butanolic extract of biomass of brown seaweed Colpomenia peregrina from the Black Sea aided in identification of 24 components, including aliphatic hydroxy and keto and aromatic acids, glycerol, mannitol, floridoside, and monosaccharides. The polysaccharide composition of the biomass was also studied, with high sodium alginate and laminaran contents and a comparatively low level of fucoidan being revealed. The polysaccharides were isolated from the biomass by fractional extraction and purified by precipitation or ion exchange chromatography. The structures of alginic acid and laminaran were deduced from 13C NMR spectra and confirmed, in the case of laminaran, by methylation analysis. The sodium alginate was shown to contain more guluronic (G) than mannuronic acid (M) residues, the M/G ratio being 0.48. Laminaran was demonstrated to be a -glucan with 1 3 linkages in its backbone and 1 6 linkages in its branching points, which is characteristic of brown algae. Fucoidan turned out to be a complex heteropolysaccharide containing, in addition to fucose and sulfate, other neutral monosaccharides and uronic acids. 相似文献
5.
N. Usov 《Russian Journal of Marine Biology》2005,31(3):203-203
6.
Andriianova DA Smirnova GP Galanina LA Feofilova EP Usov AI 《Bioorganicheskaia khimiia》2012,38(2):251-256
Preliminary data on the polysaccharide composition of mycelium of the submerged grown fungus Cunninghamella japonica (synonymous with C. echinulata) were obtained. Mild acid hydrolysis of the mycelium led to formation of glucose, mannose and galactose, whereas acid treatment under drastic conditions afforded glucosamine as the hydrolysis product of chitin and chitosan, the summary content of both glucosaminoglycans being estimated as about 35%. Sequential treatment of the mycelium with hot water, 2% aqueous NaOH and 10% AcOH gave rise to several polysaccharide fractions, which were characterized by their monosaccharide composition. The yield ofchitosan extracted by AcOH was negligible. Additional purification of the fraction obtained by the action of alkali afforded a polysaccharide preparation, which was shown to be a linear (1-->3)-alpha-D-glucopyranan according to the data of chemical methods of structural analysis and NMR spectroscopy. It was concluded that Cunninghamella japonica differs from several other known representatives of Mucorales by the presence of this alpha-D-glucan, as well as by low content of chitosan and polyuronides. 相似文献
7.
TANATIN BI 《Mikrobiologiia》1951,20(6):506-511
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Natalia V Potekhina Alexander S Shashkov Lyudmila I Evtushenko Ekaterina Yu Gavrish Sofya N Senchenkova Andrey A Stomakhin Anatolii I Usov Irina B Naumova Erko Stackebrandt 《European journal of biochemistry》2003,270(22):4420-4425
The cell wall of Brevibacterium sp. VKM Ac-2118 isolated from a frozen (mean annual temperature -12 degrees C) late Pliocene layer, 1.8-3 Myr, Kolyma lowland, Russia, contains mannitol teichoic acid with a previously unknown structure. This is 1,6-poly(mannitol phosphate) with the majority of the mannitol residues bearing side phosphate groups at O-4(3). The structure of the polymer was established by chemical methods, NMR spectroscopy, and MALDI-TOF mass spectrometry. 相似文献
10.
E.V. Nikolaeva A.I. Usov A.P. Sinitsyn A.H. Tambiev 《Journal of applied phycology》1999,11(4):385-389
Several new crude enzyme preparations were isolated from a marine association of the agarolytic bacterium Cytophaga diffluens
and the infusorium Uronema marinum, an axenic culture of Cytophaga diffluens, some species of land micro- and macromycetes
adapted to assimilate red algal biomass and from the marine mollusc Littorina littorea. Fungal and mollusc enzyme preparations
were shown to have cellulase, xylanase, protease and agarase activities. Fungal agarase activity was revealed only after 3–4
passages of the culture on the medium containing algal biomass. Enzyme preparations from the association and the pure bacterial
culture growing on the medium with bactoagar as the sole carbon source contained only agarase activity. The maximum specific
agarase activity was found in a preparation from the marine association. The preparations obtained can be used for isolating
protoplasts and single cells from red seaweed thalli.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献