Bacterial Cellulose Production from Industrial Waste and by-Product Streams.

Erminda Tsouko,Vitor Alves,Seraphim Papanikolaou,Constantina Kourmentza,Nikolaos Kopsahelis,Apostolis Koutinas,Ioanna Mandala,Fotis Paloukis,Dimitrios Ladakis

doi:10.3390/ijms160714832

Abstract

The utilization of fermentation media derived from waste and by-product streams from biodiesel and confectionery industries could lead to highly efficient production of bacterial cellulose. Batch fermentations with the bacterial strain Komagataeibacter sucrofermentans DSM (Deutsche Sammlung von Mikroorganismen) 15973 were initially carried out in synthetic media using commercial sugars and crude glycerol. The highest bacterial cellulose concentration was achieved when crude glycerol (3.2 g/L) and commercial sucrose (4.9 g/L) were used. The combination of crude glycerol and sunflower meal hydrolysates as the sole fermentation media resulted in bacterial cellulose production of 13.3 g/L. Similar results (13 g/L) were obtained when flour-rich hydrolysates produced from confectionery industry waste streams were used. The properties of bacterial celluloses developed when different fermentation media were used showed water holding capacities of 102–138 g·water/g·dry bacterial cellulose, viscosities of 4.7–9.3 dL/g, degree of polymerization of 1889.1–2672.8, stress at break of 72.3–139.5 MPa and Young’s modulus of 0.97–1.64 GPa. This study demonstrated that by-product streams from the biodiesel industry and waste streams from confectionery industries could be used as the sole sources of nutrients for the production of bacterial cellulose with similar properties as those produced with commercial sources of nutrients.

Highlights

Cellulose is the most abundant natural polymer on Earth and it is found as a structural component, often bound to other polymers
This study focuses on the evaluation of bacterial cellulose production from by-product streams generated by sunflower-based biodiesel industries and waste streams generated by the confectionery industry
Various commercial sugars and crude glycerol were initially evaluated using the same fermentation media (Figure 1) in order to determine their efficiency on bacterial cellulose (BC) production by the bacterial strain Komagataeibacter sucrofermentans DSM 15973

Summary

Introduction

Cellulose is the most abundant natural polymer on Earth and it is found as a structural component, often bound to other polymers. BC is characterized by higher purity, due to the fact that it does not contain any hemicellulose or lignin, higher water holding capacity, hydrophilicity, degree of polymerization, mechanical strength, crystallinity, porosity, and a highly pure fiber network structure, compared to plant cellulose [1]. The enhanced mechanical properties of BC occur due to the uniform, continuous and nano-scalar network of cellulosic fibers. These properties are affected by various factors, such as the culture conditions, the microorganism and the fermentation media employed. Due to the versatile properties of this highly functional biopolymer, BC can be applied in numerous end-uses including scaffold for tissue engineering applications, wound healing applications, artificial skin in extensive burns, skin tissue repair, artificial blood vessels for microsurgery, sound transducing membranes, optically transparent composites, in paper manufacturing [2], and in the food industry as a thickening and stabilizing agent [3]

Methods

Results

Conclusion