Structural Elucidation of the Exopolysaccharide Produced by Curvularia lunata Isolate RJ01
Date
2021-04-01Author
JAYUS, Jayus
AKROMAN, Robby
NURHAYATI, Nurhayati
NUGRAHA, Ari Satia
Piluharto, Bambang
SEVIOUR, Robert James
Metadata
Show full item recordAbstract
An exopolysaccharide (EPS) was recovered from culture
filtrates of the fungus Curvularia lunata isolate RJ01 prepared in Jember, Indonesia. Based on a prominent peak at 883 cm
-1
, FTIR analysis
suggested it is a β-D-glucan, a proposal confirmed by subsequent nuclear magnetic resonance (NMR) analysis which showed anomeric
protons omit the signal at 4.37 and 4.8 ppm, and sugar proton signal in the region of 2.5 to 4.2 ppm. High-performance liquid
chromatography (HPLC) analysis of the acid hydrolysates of this glucan revealed the presence of glucose (64%) and a mixture of galactose
and mannose (36%). Digestion with (13)-β- and (16)-β-glucanase from Acremonium sp. IMI 383068 gave consistent linear products of
(13)-β-glycosidic linkages, since the glucan was digested by (13)-β-glucanase only. The rheological behavior of aqueous EPS solution
suggests it behaves as a pseudoplastic non-Newtonian fluid and thus has the potential for use as a thickening agent in foods. This study is
the first report on the structural elucidation of EPS from C. lunata.