Two-dimensional NMR spectroscopic studies of fenugreek (Trigonella foenum-graecum L.) galactomannan without chemical fragmentation.

Ramesh, H. P. and Yamaki, K. and Ono, H. and Tsushida, T. (2001) Two-dimensional NMR spectroscopic studies of fenugreek (Trigonella foenum-graecum L.) galactomannan without chemical fragmentation. Carbohydrate Polymers, 45 (1). 69-77, 32 ref..

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Abstract

Structure of fenugreek galactomannan was investigated using 2 dimensional NMR spectroscopy without chemical fragmentation. Following sequential extraction of fenugreek flour with hot water, cold water and alkali, 2 fractions were obtained by Cu complex precipitation and gel chromatography. Hydrolysis of the fractions, which had galactose to mannose ratios of 1:1.04 and 1:1.12, was unaffected by Aspergillus niger beta-D-mannanase suggesting interference due to a high level of galactose substitution. A range of 1H-1H and 1H-13C correlation experiments (DQF-COSY, TOCSY, HSQC) allowed assignment and verification of all 1H and 13C signals. Assignment of anomeric 1H and confirmation of mannose backbone linkages and galactose attachment structure allowed the [4)alpha-gal-(1<right arrow>6)-beta-man-(1<right arrow>]n structure of the fenugreek galactomannan to be clarified.

Item Type:	Article
Uncontrolled Keywords:	POLYSACCHARIDES-; SPICES-; VEGETABLES-SPECIFIC; FENUGREEK-; GALACTOMANNANS-; STRUCTURE-
Subjects:	500 Natural Sciences and Mathematics > 04 Chemistry and Allied Sciences > 10 Spectroscopic and Spectrometric analysis 600 Technology > 08 Food technology > 30 Spices/Condiments > 08 Fenugreek
Divisions:	Dept. of Biochemistry
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	19 Jul 2011 05:30
Last Modified:	19 Jul 2011 05:30
URI:	http://ir.cftri.res.in/id/eprint/7654

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