Study on the Biodegradability of Konjac Glucomannan/Curdlan Composite Aerogel

Abstract

In this paper, konjac glucomannan (KGM) and curdlan (CUD) were used to prepare biomass aerogels with different mass ratios (KGM/CUD, K1C0.6, K1C0.9, K1C1.2) based on sol-gel and vacuum freeze-drying methods. The four dominant strains of Aspergillus niger (Fen), Penicillium expansum (L), P. italicum (B3) and Bacillus sp. (WE-3) were used to degrade the composite aerogel, and the degradation morphology, weight change, microscopic morphology, molecular change, thermal stability and strain growth adaptability were investigated. The results showed that the aerogels collapsed and shrinking with abundant thallus on the surface. During the degradation process of the aerogel, the water from the environment was absorbed by the hygroscopicity of KGM, and the degradation process would be accelerated. FTIR showed that the long chains of polysaccharides were degraded into short chains after degradation, and no new groups were produced. SEM pictures expressed that the porous structure of aerogel was destroyed and the three-dimensional network structure collapsed. DSC analysis showed that the thermal stability of aerogel significantly decreased. The fungi Fen, L and B3 were suitable for the growth of KC aerogel environment, while the bacteria WE-3 struggled to adapt. This research was expected to provide theoretical reference for the biodegradation of polysaccharide composites.

Keywords

• konjac glucomannan
• curdlan
• polysaccharide
• biomass aerogel
• biodegradability