Optimization of Moist and Oven-Dried Bacterial Cellulose Production for Functional Properties

Abstract

Bacterial cellulose (BC) is a natural polymer with properties suitable for tissue engineering and possible applications in scaffold production. However, current procedures have limitations in obtaining BC pellicles with the desired structural, physical, and mechanical properties. Thus, this study analyzed the optimal culture conditions of BC membranes and two types of processing: draining and oven-drying. The aim was to obtain BC membranes with properties suitable for a wound dressing material. Two studies were carried out. In the preliminary study, the medium (100 mL) was inoculated with varying volumes (1, 2, 3, 4, and 5 mL) and incubated statically for different periods (3, 6, 9, 12, and 18 days), using a full factorial experimental design. Thickness, uniformity, weight, and yield were evaluated. In the optimization study, a Box–Behnken design was used. Two independent variables were used: inoculum volume (X1: 1, 3, and 5 mL) and fermentation period (X2: 6, 12, and 18 d) to determine the target response variables: thickness, swelling ratio, drug release, fiber diameter, tensile strength, and Young’s modulus for both dry and moist BC membranes. The mathematical modelling of the effect of the two independent variables was performed by response surface methodology (RSM). The obtained models were validated with new experimental values and confirmed for all tested properties, except Young’s modulus of oven-dried BC. Thus, the optimal properties in terms of a scaffold material of the moist BC were obtained with an inoculum volume of 5% (v/v) and 16 d of fermentation. While, for the oven-dried membranes, optimal properties were obtained with a 4% (v/v) and 14 d of fermentation.

Antimicrobial Properties of Bacterial Cellulose Films Enriched with Bioactive Herbal Extracts Obtained by Microwave-Assisted Extraction

“…The static-fermentation technique under aerobic incubation was performed throughout the study. G. xylinus was statically cultured in liquid media containing 50 g/L glucose, 5 g/L yeast extract, 12.5 g/L CaCO 3 , and distilled water as solvent [ 58 ] at 26 °C for 72 h. The culture was preserved on solid medium at 4 °C and recultivated as previously described every 2 to 3 weeks [ 59 ]. The inoculum solution was prepared from the solid-culture plates by vortexing (MaxQ 2000) 7 to 9 bacterial colonies of the 7-day old G. xylinus culture for 5 min in a 9 mL sterile saline tube.…”

“…The inoculum solution was prepared from the solid-culture plates by vortexing (MaxQ 2000) 7 to 9 bacterial colonies of the 7-day old G. xylinus culture for 5 min in a 9 mL sterile saline tube. The resulted bacterial-cell suspension was adjusted to 1.5 × 10 7 cells/mL [ 60 ] using a spectrophotometer (Shimadzu UV-1900) at 600 nm absorbance and used as inoculum solution [ 59 ].…”

Static Culture Combined with Aeration in Biosynthesis of Bacterial Cellulose

“…Glucose is the monomer of BC, as for cellulose of plant origin. BC is distinct in the 3D architecture of the network structure of ultrafine fibers whose thickness varies from 20 to 100 nm [ 1 , 2 , 3 , 4 , 5 , 6 ]. BC contains constitutionally no lignin and hemicellulose impurities [ 7 ] and exhibits high values of physicochemical characteristics such as mechanical strength, water-holding capacity and crystallinity.…”

“…BC contains constitutionally no lignin and hemicellulose impurities [ 7 ] and exhibits high values of physicochemical characteristics such as mechanical strength, water-holding capacity and crystallinity. Moreover, the fundamental property of BC is its biocompatibility [ 1 , 2 , 3 , 4 , 5 , 6 ]. BC is used in various fields ranging from traditional technical and food industries to biomedicine.…”

Correction: Bodea et al. Optimization of Moist and Oven-Dried Bacterial Cellulose Production for Functional Properties. Polymers 2021, 13, 2088

“…The authors wish to make a change to the published paper [1]. In Tables 2 and 3, the units of Fiber Diameter have been changed from "µm" to "nm".…”