Structural investigation of a Novel Polysaccharide (HWSPP) from Semi-Ripe Bael Fruit Pulp (Aegle marmelos)

Gora Das1, 2,Email

Asish Kumar Sen2

1Department of Applied Sciences, Haldia Institute of Technology, Haldia 721657, India.
2Indian Institute of Chemical Biology, Kolkata 700032, India.

Abstract

The hot water-soluble extract from semi-ripe Bael (Aegle marmelos) fruit pulp was fractionated by anion exchange chromatography. The major fraction hot water soluble pectic polysaccharide (HWSPP) was found to consist of arabinose, galactose, galacturonic acid with traces of rhamnose. Methylation analysis of HWSPP showed that L-arabinose exists in three different types of linkages namely non reducing terminal L-arabinose, 3,5 linked and 1,5 linked L-arabinose in an approximate proportion of 2:1:3. D-Galactose was found to be present as non reducing terminal galactose, 1,4-linked and  3,6 linked galactose in approximate mole ratio of 2:1:1. On the basis of total acid hydrolysis, methylation analysis, periodate oxidation, and NMR studies (1H, 13C, COSY, TOCSY) the tentative structure of the polysaccharide was established as the following figure.

 

Structural investigation of a Novel Polysaccharide (HWSPP) from Semi-Ripe Bael Fruit Pulp (Aegle marmelos)