Structural and thermal analysis of a hyper-branched exopolysaccharide produced by submerged fermentation of mushroom mycelium. Issue 113 (28th November 2016)

• Record Type: Journal Article
• Authors: Chen, L.; Cheng, W. N.; Zhang, B. B.; Cheung, P. C. K.
• Is Part Of: RSC advances. Volume 6:Issue 113(2016)
• Page Start: 112260
• Page End: 112268
• Publication Date: 2016-11-28
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra23383j
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : An exopolysaccharide (PTR-EPS1) purified from the culture medium of the mycelial fermentation of Pleurotus tuber-regium had a weight-average molecular mass of 173.6 kDa and a radius of 55.6 nm. Abstract : An exopolysaccharide (PTR-EPS1) purified from the culture medium of the mycelial fermentation of Pleurotus tuber-regium had a weight-average molecular mass of 173.6 kDa and a radius of 55.6 nm. Methylation analysis and NMR results indicated that PTR-EPS1 had a 81% degree of branching at O -2 and consisted of a backbone of 1, 6-linked α-d -Man p residues branched at O -2 with either a terminal α-d -Man p or -(1, 2)-α-d -Man p -(1, 2)-α-d -Man p units. The morphology of PTR-EPS1 was found to be spherical by TEM. Thermal analysis indicated that the main thermal degradation (up to 77.56% dry mass) of PTR-EPS1 occurred within a temperature range of 205.7–331.2 °C. The apparent activation energy E a and pre-exponential factor A of PTR-RES1 were found to be 223.4 kJ mol −1 and 5.37 × 10 23 s −1, respectively. This is the first report on the structural information and thermal degradation properties of PTR-EPS1. These results will facilitate the potential application of this mushroom polysaccharide as a novel biopolymer in the design of carbohydrate-based nanoparticles and food delivery systems.