Biotechnological production of cellulose by acetic acid bacteria: current state and perspectives

Abstract

Bacterial cellulose is an attractive biopolymer for a number of applications including food, biomedical, cosmetics, and engineering fields. In addition to renewability and biodegradability, its unique structure and properties such as chemical purity, nanoscale fibrous 3D network, high water-holding capacity, high degree of polymerization, high crystallinity index, light transparency, biocompatibility, and mechanical features offer several advantages when it is used as native polymer or in composite materials. Structure and properties play a functional role in both the biofilm life cycle and biotechnological applications. Among all the cellulose-producing bacteria, acetic acid bacteria of the Komagataeibacter xylinus species play the most important role because they are considered the highest producers. Bacterial cellulose from acetic acid bacteria is widely investigated as native and modified biopolymer in functionalized materials, as well as in terms of differences arising from the static or submerged production system. In this paper, the huge amount of knowledge on basic and applied aspects of bacterial cellulose is reviewed to the aim to provide a comprehensive viewpoint on the intriguing interplay between the biological machinery of synthesis, the native structure, and the factors determining its nanostructure and applications. Since in acetic acid bacteria biofilm and cellulose production are two main phenotypes with industrial impact, new insights into biofilm production are provided.

Production of high crystallinity type‐I cellulose from Komagataeibacter hansenii JR‐02 isolated from Kombucha tea

“…Various BC producing microorganisms had been found and identified, such as Agrobacterium , Pseudomonas , Rhizobium , and Sarcina since Brown isolated the first strain named Acetobacter xylinus in 1886 . Among the BC producing bacteria, Komagataeibacter genus was considered as the mainstream bacteria of BC production because of their high productivity . As literatures reported, Acetobacter sp.…”

Biobased Materials from Microbial Biomass and Its Derivatives

“…The reasons for considering microbial cellulose as an attractive biobased material are the conformational structure and enhanced properties compared to plant cellulose. Its chemical purity, nanoscale fibrous network, high water-holding capacity, hydrophilicity, high degree of polymerization and crystallinity index, good chemical stability, transparency, biocompatibility, renewability, biodegradability, and superior mechanical strength are the extraordinary features that offer several advantages when it is used as a native polymer or in composite materials [98,[102][103][104].…”

“…AAB are mesophilic and strictly aerobic bacteria occurring in sugary, alcoholic, and acidic environments (pH 4 to 6), such as fruits, flowers, and particularly fermented beverages. They participate in partial oxidation of carbohydrates releasing aldehydes, ketones, and organic acids into the surrounding media, through "oxidative fermentations" [103,[106][107][108].…”

“…Table 3 shows that glucose concentration varied from 20 to 100 g/L, resulting in a maximum conversion yield of 0.85 g cellulose/g glucose. Glucose participates in respiratory metabolism, producing gluconic acids and extracellular cellulose as a protective mechanism [103,115].…”

“…Like the exopolysaccharide acts as cell support by attaching them, the membrane prevents cell dehydration, provides protection to cells from harsh conditions, like as UV radiation, external microorganism contamination, and against antimicrobial compounds by limiting its diffusion and increasing cell density. Cellulose membrane also helps the bacteria to become floatable, via entrapment of carbon dioxide produced in fermentation, allowing the bacteria to reach the air-liquid interface as a mechanism to take oxygen [103,105,110,116].…”