Neutral carbohydrates

In the present paper we describe a contribution of the neutral carbohydrate chains in PG-lc for expression of its anti-complementary and mitogenic activities. 

Determination of neutral carbohydrate Total neutral carbohydrate in protein samples was estimated by the phenol/sulphuric acid method of Dubois [13] using mannose as standard. 

R. A. Hamlen, F. L. Lukezic, and J. R. Bloom, Influence of age and stage of development on the neutral carbohydrate components in root exudates from alfalfa plants grown in a gnotobiotic environment, Canadian Journal of Plant Science 52 633 (1972). 

Hernes, P.J., J.I. Hedges, M.L. Peterson, S.G. Wakeham, and C. Lee. 1996. Neutral carbohydrate geochemistry of particulate material in the central equatorial Pacific. Deep-Sea Research 1143 1181-1204. 

A unique anion-exchange column has been developed that has a thin (non-diffusion limited) anion-exchange phase coated onto a 10-/nm latex bead. When a mobile phase of 0.15 M NaOH is used, neutral carbohydrates are converted into anions, which are separated on the column. Although the resin has low capacity, and probably causes degradation of the carbohydrates, when it is coupled to a triple-pulsed, amperometric detector, the system provides extremely sensitive, high-resolution separations. 

Antipova, A.S., Semenova, M.G. (1997a). Effect of neutral carbohydrate structure in the set glucose / sucrose / maltodextrin / dextran on protein surface activity at the air-water interface. Food Hydrocolloids, 11, 71-77. 

Antipova, A., Semenova, M., Gauthier-Jacques, A. (1997). Effect of neutral carbohydrate structure on protein surface activity at air-water and oil-water interfaces. In Dickinson, E., Bergenstahl, B. (Eds). Food Colloids Proteins, Lipids and Polysaccharides, Cambridge, UK Royal Society of Chemistry, pp. 245-258. 

Reineccius, G. A., Kavanagh, T. E. and Keeney, R G. 1970. Identification and quantitation of free neutral carbohydrates in milk products by gas-liquid chromatography and mass spectrometry. J. Dairy Sci. 53, 1018-1022. 

The CBH I (D) is identical in composition and activity to the CBH I (D) previously described (2) from T. reesei QM 9123. The close correspondence of their amino acid contents (Table VI), the nearly identical content of neutral carbohydrate 6.8% by weight for the CBH I (D) produced in the presence of sophorose and 6.7% for T. reesei QM 9123 CBH I (D) grown on cellulose (2), and identical electrophoretic properties clearly argue for a common molecular structure for these CBH s I (D). The CBH II is clearly different from all other CBH s in electrophoretic mobility (Figure 12) and amino acid composition (41), but is devoid of endoglucanase activity and produces predominantly cellobiose (>90% by weight of soluble products) from cellulose. It has a sedimentation coefficient of 3.71 in comparison to CBH I (D), for which a value of 3.66 was obtained. 

The neutral carbohydrates, such as glucose, P-cyclodextrin, or arabinogalactan needed to be present in much higher amounts than the other carbohydrates to inhibit the aggregation. This low affinity of neutral carbohydrates for complexation of tannins has been reported by other authors [65, 83]. 

Aldonic, uronic, and ascorbic acids, lactones, and N-acetylated amino sugars were separated on sulfonated polystyrene-divinylbenzene, a strong polyanion exchanger (Wheaton and Bauman, 1953). This method is adaptable to neutral carbohydrates without complexation or adsorption, by immersion in strong alkali to ionize the hydroxyl groups (ion chromatography). 

I. Ciucanu and R. Carpita, Per-O-methylation of neutral carbohydrates directly from aqueous samples for gas chromatography and mass spectrometry analysis, Anal. Chim. Acta, 585 (2007) 81-85. 

In general, the effectiveness of carbohydrates to prevent protein-tannin aggregation increase with their ionic character (Luck et al. 1994 Carvalho et al. 2006b de Freitas et al. 2003) neutral carbohydrates practically do not affect aggregation. 

Cheng, X. H., and Kaplan, L. A. (2003). Simultaneous analyses of neutral carbohydrates and amino sugars in freshwaters with HPLC-PAD. J. Chromatogr. Sci. 41(8), 434-438. 

The borate buffer is necessary to complex the neutral carbohydrates to give them ionic properties that then allow separation by anion exchange chromatography. A sodium tetraborate-boric acid buffer (pH 8.5) whose composition varies from 0.169 to 0.845 Af in the borate ion is used as the eluent. The anion exchange separation column is maintained at a constant 55°C. 

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