Preparation and Structural Properties of Bacterial Nanocellulose Obtained from Beetroot Peel Medium

Abstract

The aim of the present study was to investigate structural modifications and physicochemical properties of bacterial nanocellulose (BNC) pellicles produced statically in a beetroot peel medium as a mixture of C-sources (8% sucrose, 2% glucose, and 0.86% fructose). Characteristics of these BNC samples were compared to those produced using a chemically defined and modified Hestrin–Schramm medium with 3% (w/v) glucose, fructose, and sucrose as sole carbon sources. Compared with the beetroot peel medium, where 11.57 g/L BNC (wet weight) was obtained, glucose gave the highest BNC yield (13.07 g/L), sucrose 10.55 g/L, and fructose 7.9 g/L. FT-IR spectra showed almost identical chemical profiles assigned to cellulose I. XRD analysis revealed that the BNC produced in beetroot peel medium had a larger crystallite size than other BNC samples. The crystallinity index of beetroot peel BNC was higher than that of Hestrin–Schramm BNC. The water-holding capacity, water release rate, and iodine sorption value from the beetroot peel medium were greater than those of other BNCs. Furthermore, as there is a necessity today to find cheaper carbon sources to obtain valuable products at a lower cost, beetroot peels represent an interesting alternative to producing BNC as a new functional material for industrial applications.

Keywords

• bacterial nanocellulose (BNC)
• beetroot peels
• agroindustrial wastes
• crystal structure
• water-holding capacity