Functional evaluation of exopolysaccharide from Pseudozyma sp. NII 08165 revealed the potential thickening and emulsifying applicability

Abstract

Exopolysaccharides (EPSs) have huge commercial potential as additives in food, personal care and pharmaceutical formulations. The physicochemical properties, in particularly rheological behaviour of an EPS, determine its potential application. In the present study, we investigated the structural, rheological, emulsifying, flocculating and water holding properties of Pseudozyma EPS in relation to its potential for industrial applications. Pseudozyma sp. NII 08165 was previously reported to produce an EPS of 1.7 MDa with high viscosity and pseudoplastic behaviour. Congo red assay indicated an ordered helical conformation of theEPS that could impart many desirable attributes. Comparative analysis of the EPS with respect to xanthan gum revealed that it had significant thickening efficiency and moderate suspending ability. Rheology of Pseudozyma EPS was stable up to 60°C and over the pH range 4.0-9.0. EPS exhibited superior flocculating activity and its emulsifying activity was as good as that of xanthan gum. The Pseudozyma EPS also demonstrated adequate water holding capacity. These results revealed that the Pseudozyma EPS could be used as a potential thickener, emulsifying agent or flocculating agent for diverse applications.