Structural studies of a heteropolysaccharide (PS-I) isolated from hot water extract of fruits of Psidium guajava (Guava)

A water-soluble polysaccharide was isolated from hot aqueous extracts of fruits of Psidium guajava. The polysaccharide was found to contain 2-O-methyl-l-arabinose, 2-O-acetyl-d-galactose, and d-methyl galacturonate in a molar ratio of approximately 1:1:1. On the basis of acid hydrolysis, methylation analysis, periodate oxidation, and NMR studies (1H, 13C, TOCSY, DQF-COSY, NOESY, ROESY, HMQC, and HMBC), the structure of the repeating unit of the polysaccharide was established as Figure optionsDownload as PowerPoint slide

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