Optimization of bacterial nanocellulose fermentation using recycled paper sludge and development of novel composites

Abstract

In this work, recycled paper sludge (RPS), composed of non-recyclable fibres, was used as a carbon source for bacterial nanocellulose (BNC) production. The biomass was enzymatically hydrolysed with Cellic CTec 2 to produce a sugar syrup with 45.40 g/L glucose, 1.69 g/L cellobiose and 2.89 g/L xylose. This hydrolysate was used for the optimization of BNC fermentation by static culture, using Komagataeibacter xylinus ATCC 700178, through response surface methodology (RSM). After analysis and validation of the model, a maximum BNC yield (5.69 g/L, dry basis) was obtained using 1.50% m/v RPS hydrolysate, 1.0% v/v ethanol and 1.45% m/v yeast extract/peptone (YE/P). Further, the BNC obtained was used to produce composites. A mixture of an amino-PolyDiMethylSiloxane-based softener, polyethyleneglycol (PEG) 400 and acrylated epoxidized soybean oil (AESO), was incorporated into the BNC membranes through an exhaustion process. The results show that BNC composites with distinct performances can be easily designed by simply varying the polymers percentage contents. This strategy represents a simple approach towards the production of BNC and BNC-based composites.

Production and characterization of Komagataeibacter xylinus SGP8 nanocellulose and its calcite based composite for removal of Cd ions

“…The BNC yield obtained in the present work is comparable to the reports of Molina-Ramírez et al (2017) and Zhang et al (2014), where they achieved cellulose production of 2.8 g L −1 and 3.5 g L −1 for K. medellinensis and G. xylinus, respectively after 8 days of fermentation in glucose (2-2.5% w/v) containing media. Likewise cellulose production of 5.69 g L −1 using K. xylinus ATCC700178 in media laden with 4.5% glucose in the form of recycled paper hydrolyzate have also been reported by Soares da Silva et al (2019).…”

Application of Bacterial Cellulose in the Textile and Shoe Industry: Development of Biocomposites

“…In our previous works, BC was used as a structuring material for the development of a new leather analogue from alternative biological products, specifically modified vegetable oils and other hydrophobic polymers. BC was submitted to an exhaustion process, allowing the bulk impregnation of hydrophobic polymers such as commercial nano/microparticles, Persoftal MS Con.01 (polydimethylsiloxane (PDMS)-based) and Baygard EFN (perfluorocarbon (PFC)-based) and acrylated epoxidized soybean oil (AESO) [59][60][61]. In our first approach, BC-based nanocomposites were developed by impregnating BC membranes with PDMS-based or PFC-based products, either separately or combined in a sequential process.…”

“…Then, aiming at increasing the bio-based content of the composite, BC membranes were impregnated with acrylated epoxidized soybean oil (AESO) in a mixture also containing the PDMS-based polymer and polyethylene glycol (PEG) 400 as a plasticizer, yielding a product with greater elasticity and improved BC-polymers interfacial adhesion. The hydrophobic BC composites owned distinct performances, which were manipulated by varying the percentage of the polymer [59]. Using another approach, AESO resin was emulsified prior to the exhaustion process to allow its better diffusion into the bulk of the BC 3D network, being used in mixtures containing PEG 400, PDMS-based and PFC-based products.…”

Exploration of a novel and efficient source for production of bacterial nanocellulose, bioprocess optimization and characterization

“…One way to reduce the total cost of producing BNC is to identify a low-cost and renewable carbon source through bioprocess optimization of the growth medium that can increase the BNC yield 12 . In recent years, several experimental studies have been conducted to reduce the production costs by using efficient and cost-effective culture medium and various waste products such as rotten fruits 13 , fruit juices as citrus juice 14 kiwifruit peel hydrolysate (Güzel and Akpınar, 2020) 15 , apple peel hydrolysate 15 , pineapple peel waste 16 , recycled paper sludge hydrolysate 17 and an extract of banana peel waste 16 . Food wastes contain mostly carbon sources in the form of simple sugar or complex fiber.…”

“…Take pineapple peel juice derived from pineapple waste as an example; it has a high sugar content (73.76 g/L of total sugar), which is primarily made up of glucose, sucrose, and fructose. Conversely, the peels of pineapple are cellulose fibers that can be further processed to produce simple sugar 17 , 18 .…”