Bacterial Nanocellulose Production Research Articles

Bacterial nanocellulose production: Improvement in productivity and properties via a sustainable medium

High production cost is a significant barrier to commercial bacterial nanocellulose (BNC) production. This study addresses this issue using a low-cost molasses and cheese whey medium via Gluconacetobacter hansenii. The one-factor-at-a-time method investigated the effect of critical factors on BNC production, including total sugar and total protein concentrations (g/L), initial pH, and additives such as ethanol and acetic acid (%(v/v)). The productivity in the HS medium was 0.125 g/L/day, while the low-cost medium without additives achieved a productivity of 0.5275 g/L/day. Although the addition of ethanol decreased the productivity, the inclusion of 0.4 %(v/v) acetic acid increased the productivity to 0.64 g/L/day. Using the low-cost medium with acetic acid led to a 40-fold reduction in production costs compared to the HS medium. Furthermore, transitioning from HS media to the low-cost medium resulted in BNC with thicker fibres, a higher crystallinity index (%) and improved mechanical properties. The ratio of Iα/ Iβ in BNC produced in HS media decreased from 1.68 to 1.09 in the low-cost medium. The thermal properties of BNC produced in the low-cost medium also showed slight improvements compared to those in the HS medium. The degree of polymerization significantly increased from 1096 to 1457 in the low-cost medium compared to HS media. These findings highlight the potential of using a low-cost medium to produce BNC with enhanced properties, offering a sustainable and cost-effective alternative to conventional plastics.

Optimization of Citrus Pulp Waste-Based Medium for Improved Bacterial Nanocellulose Production.

Bacterial nanocellulose (BC) has attracted significant attention across a wide array of applications due to its distinctive characteristics. Recently, there has been increasing interest in leveraging waste biomass to improve sustainability in BC biogenesis processes. This study focuses on optimizing the citrus pulp waste (CPW) medium to enhance BC production using Komagataeibacter sucrofermentans. The screening of initial medium pH, yeast extract, CPW sugar and inoculum concentrations was conducted using the Plackett-Burman design, with BC yield (mgDW/gCPW) as the model response. The significant parameters, i.e., CPW sugars and yeast extract concentrations, were optimized using response surface methodology, employing a five-level, two-factor central composite design. The optimized CPW-based growth medium resulted in a final yield of 66.7 ± 5.1 mgDW/gCPW, representing a 14-fold increase compared to non-optimized conditions (4.3 ± 0.4 mgBC/gCPW). Material characterization analysis indicated that the produced BC showed high thermal stability (30% mass retained at 600 °C) and a crystallinity index value of 71%. Additionally, to enhance process sustainability, spent baker's yeast hydrolysate (BYH) was assessed as a substitute for yeast extract, leading to a final BC titer of 9.3 ± 0.6 g/L.

Fruit Wastes and Crop Residues as Nutrient Sources for Bacterial Nanocellulose Production: A Review

Nanocellulose has been developed and used as a bio-based advanced material in modern biotechnology. Lately, bacterial nanocellulose (BNC) emerged as a prominent biopolymer because of its multi-functional application in various industries, such as food, biomedical, cosmetics, and environmental. The emerging concern for large-scale BNC production is the high fermentation costs, low productivity, and expensive culture medium. To minimise this issue, agro-industrial wastes can be used as feedstock. Recently, many studies have investigated the utilization of agro-industrial wastes as potential nutrient sources for BNC production. However, a comprehensive review of BNC production from fruit wastes and crop residues is lacking. To address this gap, the current review focuses on the utilization of fruit wastes and crop residues for BNC production, including its advantages and disadvantages. This study contributes to the scientific community by (a) providing an insight into fruit waste and crop residue utilization for BNC synthesis (b) an overview on its advantages and disadvantages (c) providing recommendations and future perspectives on BNC production from agro-industrial waste utilization. The sustainable concept of BNC production utilizing agro-industrial wastes opens a way for industries to produce BNC on a larger scale.

Characterization of Bacterial Nanocellulose Produced by Tropical Fruit‐Derived Bacteria in Coconut Water Medium Supplemented with Pineapple Peel Extract

AbstractAgro‐industrial residues, such as surplus fruits and vegetables are increasingly recognized as valuable sources for isolating bacterial strains capable of efficiently producing bacterial nanocellulose (BNC). This study presents a novel approach to BNC production using Komagataeibacter intermedius SB 110 isolated from rotten pineapple, cultivated in a sustainable medium of coconut water enriched with 5% sucrose and 0.5% pineapple peel extract. By leveraging agricultural waste, this method accelerates BNC biosynthesis to less than 7 days and achieves a yield of 5.563 g/L over 14 days, a 1.58‐fold increase compared with traditional media. The BNCs were primarily composed of cellulose type I, with minor cellulose type II, ultrafine fiber sizes (58.3 to 84.98 nm) and a high crystallinity index (60.81% to 78.34%), indicating superior structural quality. This innovative process not only demonstrates the potential of using low‐cost, sustainable substrates for high‐yield BNC production but also significantly enhances both the efficiency and scalability of the production process, setting a new standard over existing methods.

Bacterial valorization of agricultural-waste into a nano-sized cellulosic matrix for mitigating emerging pharmaceutical pollutants: An eco-benign approach

For Bacterial Nanocellulose (BNC) production, standard methods are well-established, but there is a pressing need to explore cost-effective alternatives for BNC commercialization. This study investigates the feasibility of using syrup prepared from maize stalk as a valuable nutrient and sustainable carbon source for BNC production. Our study achieved a remarkable BNC production yield of 19.457 g L−1 by utilizing Komagataeibacter saccharivorans NUWB1 in combination with components from the Hestrin-Schramm (HS) medium. Physicochemical properties revealed that the obtained BNC exhibited a crystallinity index of 60.5 %, tensile strength of 43.5 MPa along with enhanced thermostability reaching up to 360 °C. N2 adsorption-desorption isotherm of the BNC displayed characteristics of type IV, indicating the presence of a mesoporous structure. The produced BNC underwent thorough investigation, focusing on its efficacy in addressing environmental concerns, particularly in removing emerging pharmaceutical pollutants like Metformin and Paracetamol. Remarkably, the BNC exhibited strong adsorption capabilities, aligning with the Langmuir isotherm and pseudo-second-order model. Thermodynamic analysis confirmed a spontaneous and endothermic adsorption process. Furthermore, the BNC showed potential for regeneration, enabling up to five recycling cycles. Cytotoxicity and oxidative stress assays validated the biocompatibility of BNC. Lastly, the BNC films displayed an impressive 88.73 % biodegradation within 21 days.

BNC production of siwalan neer and sugarcane molasses as novel media sources

Bacterial nanocellulose (BNC) is a unique biopolymer with remarkable purity and material properties that distinguish it from plant-derived cellulose by its absence of lignin and hemicellulose. Recent research has focused on using organic waste materials as alternative substrates to reduce the cost of BNC production. This study examines the efficacy of Siwalan neer and sugarcane molasses as novel media for cultivating Komagataeibacter xylinus by comparing their performance with that of Hestrin and Schramm (HS) medium. The BNC harvested from these alternative media was rigorously characterized using scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and Thermogravimetric Analysis (TGA) to evaluate its structural and thermal properties. Notably, the use of Siwalan neer and sugarcane molasses as growth substrates enabled K. xylinus to produce BNC at a yield of 3.83 g/L, significantly exceeding the yield from the HS medium, which was 1.46 g/L. These findings highlight the potential of leveraging alternative substrates to enhance BNC production yield, cost-effectiveness, and environmental sustainability.

Effect of addition of γ-poly glutamic acid on bacterial nanocellulose production under agitated culture conditions.

Bacterial nanocellulose (BNC), a natural polymer material, gained significant popularity among researchers and industry. It has great potential in areas, such as textile manufacturing, fiber-based paper, and packaging products, food industry, biomedical materials, and advanced functional bionanocomposites. The main current fermentation methods for BNC involved static culture, as the agitated culture methods had lower raw material conversion rates and resulted in non-uniform product formation. Currently, studies have shown that the production of BNC can be enhanced by incorporating specific additives into the culture medium. These additives included organic acids or polysaccharides. γ-Polyglutamic acid (γ-PGA), known for its high polymerization, excellent biodegradability, and environmental friendliness, has found extensive application in various industries including daily chemicals, medicine, food, and agriculture. In this particular study, 0.15g/L of γ-PGA was incorporated as a medium additive to cultivate BNC under agitated culture conditions of 120rpm and 30℃. The BNC production increased remarkably by 209% in the medium with 0.15g/L γ-PGA and initial pH of 5.0 compared to that in the standard medium, and BNC production increased by 7.3% in the medium with 0.06g/L γ-PGA. The addition of γ-PGA as a medium additive resulted in significant improvements in BNC production. Similarly, at initial pH levels of 4.0 and 6.0, the BNC production also increased by 39.3% and 102.3%, respectively. To assess the characteristics of the BNC products, scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis were used. The average diameter of BNC fibers, which was prepared from the medium adding 0.15g/L γ-PGA, was twice thicker than that of BNC fibers prepared from the control culture medium. That might be because that polyglutamic acid relieved the BNC synthesis from the shear stress from the agitation. This experiment held great significance as it explored the use of a novel medium additive, γ-PGA, to improve the production and the glucose conversion rate in BNC fermentation. And the BNC fibers became thicker, with better thermal stability, higher crystallinity, and higher degree of polymerization (DPv). These findings lay a solid foundation for future large-scale fermentation production of BNC using bioreactors.

Citrate-buffered Yamanaka medium allows to produce high-yield bacterial nanocellulose in static culture using Komagataeibacter strains isolated from apple cider vinegar.

Bacterial nanocellulose (BNC) is a sustainable, renewable, and eco-friendly nanomaterial, which has gained great attentions in both academic and industrial fields. Two bacterial nanocellulose-producing strains (CVV and CVN) were isolated from apple vinegar sources, presenting high 16S rRNA gene sequence similarities (96%-98%) with Komagataeibacter species. The biofilm was characterized by scanning electron microscopy (SEM), revealing the presence of rod-shaped bacteria intricately embedded in the polymeric matrix composed of nanofibers of bacterial nanocellulose. FTIR spectrum and XRD pattern additionally confirmed the characteristic chemical structure associated with this material. The yields and productivities achieved during 10 days of fermentation were compared with Komagataeibacter xylinus ATCC 53524, resulting in low levels of BNC production. However, a remarkable increase in the BNC yield was achieved for CVV (690% increase) and CVN (750% increase) strains at day 6 of the fermentation upon adding 22mM citrate buffer into the medium. This effect is mainly attributed to the buffering capacity of the modified Yakamana medium, which allowed to maintain pH close to 4.0 until day 6, though in combination with additional factors including stimulation of the gluconeogenesis pathway and citrate assimilation as a carbon source. In addition, the productivities determined for both isolated strains (0.850 and 0.917gL-1 d-1) compare favorably to previous works, supporting current efforts to improve fermentation performance in static cultures and the feasibility of scaling-up BNC production in these systems.

Advances in the Production of Sustainable Bacterial Nanocellulose from Banana Leaves.

Interest in bacterial nanocellulose (BNC) has grown due to its purity, mechanical properties, and biological compatibility. To address the need for alternative carbon sources in the industrial production of BNC, this study focuses on banana leaves, discarded during harvesting, as a valuable source. Banana midrib juice, rich in nutrients and reducing sugars, is identified as a potential carbon source. An optimal culture medium was designed using a simplex-centroid mixing design and evaluated in a 10 L bioreactor. Techniques such as Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) were used to characterize the structural, thermal, and morphological properties of BNC. Banana midrib juice exhibited specific properties, such as pH (5.64), reducing sugars (15.97 g/L), Trolox (45.07 µM), °Brix (4.00), and antioxidant activity (71% DPPH). The model achieved a 99.97% R-adjusted yield of 6.82 g BNC/L. Physicochemical analyses revealed distinctive attributes associated with BNC. This approach optimizes BNC production and emphasizes the banana midrib as a circular solution for BNC production, promoting sustainability in banana farming and contributing to the sustainable development goals.

Production of bacterial nanocellulose as green adsorbent matrix using distillery wastes for dye removal: a combined approach for waste management and pollution mitigation

Production of bacterial nanocellulose as green adsorbent matrix using distillery wastes for dye removal: a combined approach for waste management and pollution mitigation

Multiphase Under-Liquid Biofabrication With Living Soft Matter: A Route to Customize Functional Architectures With Microbial Nanocellulose.

The growth of aerobic microbes at air-water interfaces typically leads to biofilm formation. Herein, a fermentative alternative that relies on oil-water interfaces to support bacterial activity and aerotaxis is introduced. The process uses under-liquid biofabrication by structuring bacterial nanocellulose (BNC) to achieve tailorable architectures. Cellulose productivity in static conditions is first evaluated using sets of oil homologues, classified in order of polarity. The oils are shown for their ability to sustain bacterial growth and BNC production according to air transfer and solubilization, both of which impact the physiochemical properties of the produced biofilms. The latter are investigated in terms of their morphological (fibril size and network density), structural (crystallinity) and physical-mechanical (surface area and strength) features. The introduced under-liquid biofabrication is demonstrated for the generation of BNC-based macroscale architectures and compartmentalized soft matter. This can be accomplished following three different routes, namely, 3D under-liquid networking (multi-layer hydrogels/composites), emulsion templating (capsules, emulgels, porous materials), and anisotropic layering (Janus membranes). Overall, the proposed platform combines living matter and multi-phase systems as a robust option for material development with relevance in biomedicine, soft robotics, and bioremediation, among others.

Bacterial nanocellulose: A versatile biopolymer production using a cost-effective wooden disc based rotary reactor.

Bacterial nanocellulose (BNC) has various unique qualities, including high mechanical strength, crystallinity, and high water-holding capacity, which makes it appropriate for a wide range of industrial applications. But its lower yield coupled with its high production cost creates a barrier to its usage. In this study, we have demonstrated the better yield of BNC from an indigenous strain Komagataeibacter rhaeticus MCC-0157 using a rotary disc bioreactor (RDB) having a wooden disc. The RDB was optimized based on the type of disc material, distance between the disc, and rotation speed to get the highest yield of 13.0 g/L dry material using Hestrin-Schramm (H-S) medium. Further, the bioreactor was compared for the BNC production using reported medium, which is used for static condition; the RDB showed up to fivefold increase in comparison with the static condition reported. Komagataeibacter rhaeticus MCC-0157 was previously reported to be one of the highest BNC producing stains, with 8.37 g/L of dry yield in static condition in 15 days incubation. The designed RDB demonstrated 13.0 g/L dry yield of BNC in just 5 days. Other characteristics of BNC remain same as compared with static BNC production, although the difference in the crystallinity index was observed in RDB (84.44%) in comparison with static (89.74%). For the first time, wooden disc was used for rotary bioreactor approach, which demonstrated higher yield of BNC in lesser time and can be further used for sustainable production of BNC at the industrial level.

Targeting Bacterial Nanocellulose Properties through Tailored Downstream Techniques.

Bacterial nanocellulose (BNC) is a biodegradable polysaccharide with unique properties that make it an attractive material for various industrial applications. This study focuses on the strain Komagataeibacter medellinensis ID13488, a strain with the ability to produce high yields of BNC under acidic growth conditions and a promising candidate to use for industrial production of BNC. We conducted a comprehensive investigation into the effects of downstream treatments on the structural and mechanical characteristics of BNC. When compared to alkaline-treated BNC, autoclave-treated BNC exhibited around 78% superior flexibility in average, while it displayed nearly 40% lower stiffness on average. An SEM analysis revealed distinct surface characteristics, indicating differences in cellulose chain compaction. FTIR spectra demonstrated increased hydrogen bonding with prolonged interaction time with alkaline solutions. A thermal analysis showed enhanced thermal stability in alkaline-treated BNC, withstanding temperatures of nearly 300 °C before commencing degradation, compared to autoclaved BNC which starts degradation around 200 °C. These findings provide valuable insights for tailoring BNC properties for specific applications, particularly in industries requiring high purity and specific mechanical characteristics.

Transcriptomic Insights into Metabolism-Dependent Biosynthesis of Bacterial Nanocellulose.

Bacterial nanocellulose (BNC) is an attractive green-synthesized biomaterial for biomedical applications and various other applications. However, effective engineering of BNC production has been limited by our poor knowledge of the related metabolic processes. In contrast to the traditional perception that genome critically determines biosynthesis behaviors, here we discover that the glucose metabolism could also drastically affect the BNC synthesis in Gluconacetobacter hansenii. The transcriptomic profiles of two model BNC-producing strains, G. hansenii ATCC 53582 and ATCC 23769, which have highly similar genomes but drastically different BNC yields, were compared. The results show that their BNC synthesis capacities were highly related to metabolic activities such as ATP synthesis, ion transport protein assembly, and carbohydrate metabolic processes, confirming an important role of metabolism-related transcriptomes in governing the BNC yield. Our findings provide insights into the microbial biosynthesis behaviors from a transcriptome perspective, potentially guiding cellular engineering for biomaterial synthesis.

Isolation of cellulose-producing bacteria (Komagataeibacter Saccharivorans) from rotten sapodilla fruit

Bacterial nanocellulose (BNC) is a nanocellulose produced by bacteria with high purity, crystallinity level, water binding ability, a high degree of polymerization, and excellent mechanical characteristics. The selection of BNC-producing bacteria is one of the critical stages in the production of BNC. This study collected samples from fruit sources and was selected to determine isolates that could produce BNC. Based on the 16s rRNA strain analysis, sapodilla isolate has an identity percentage above 98%, so it can be concluded that it has similarities with the bacteria Komagataeibacter saccharivorans. From eleven sources of fruit, two isolates that have the potential to produce cellulose, namely isolate sapodilla, were obtained. The confirmed sapodilla isolate is an acetic acid bacteria, Komagataeibacter saccharivorans. The yield of BNC-made isolate sapodilla Komagataeibacter saccharivorans (0.432 g/L). Confirmed sapodilla isolates that produce cellulose were mainly determined as cellulose I (adsorption at around 3345, 1430, 1160, and 900 cm−1). Few celluloses II (adsorption at about 1335, 1315, and 1280 cm−1 and a blue-shift of the number of waves from 1430 to around 1425 cm−1) and has a crystallinity index of 52.387 % on HS (Hestrin Scrahm) media with diameter nanofibril about 86.46 nm.

Boosting bacterial nanocellulose production from chemically recycled post-consumer polyethylene terephthalate

The circular economy is emerging with new sustainable solutions to the ever-growing plastic waste challenge, garnering increasing attention. In this study, the possibility to modify expensive Hestrin–Schramm medium (HS) for bacterial nanocellulose (BNC) production and replace significant amounts of glucose with terephthalic acid (TPA) derived after reactive extrusion processing of mixed plastic waste yielding post consumer TPA (pcTPA), was evaluated from laboratory scale to fermentation at pilot scale. Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Thermogravimetric Analysis (TGA) were used to assess the structural, thermal, and morphological properties of BNC and its generated derivatives. The study's findings highlight the positive impact of pcTPA on BNC yield, surpassing the performance of conventional TPA. The presence of pcTPA in the medium resulted in a BNC yield of 4.01 g/L in a scale-up step of 100 mL cultivation, while the positive control using glucose resulted in a yield of 3.57 g/L. The efficiency of glucose substitution with pcTPA increased with each scale-up step, ultimately reaching a 320% yield increase in comparison to the positive control. Additionaly, the procedure that enhanced the materials' thermoplasticity in the form of derivatives has been established resulting in the production of BNC laurate and BNC octanoate derivatives with melting temperatures of 270 °C and 280 °C, respectively. Overall, this study investigates the potential of this approach as an important circular economic solution, enabling an increased sustainable perspective for polyethylene terephthalate (PET) circularity and significantly a much needed cost reduction for BNC production with enhanced thermoplasticity.

Bacterial nanocellulose-Robust preparation and application—A literature review

Increasing attention is being paid to bacterial nanocellulose (BNC) because of its environment-friendly properties. Researchers investigated the role of microbial hosts in BNC production due to the benefits of cellulose produced by microbes. Several research groups have developed techniques to make BNC on a large scale with the goal of developing new methods. A 3D network of micro and nanofibrils in BNC synthesized from several bacterial strains makes these BNC useful for reinforcing nanostructured composites that have increased Young’s modulus, tensile strength, purity, crystallinity, and water holding capacity. To overcome the barriers associated with the industrial scale production of BNC, different production techniques will be used, including static culture, cell-free production, agitated/shaking culture, using a variety of receptors for fermentation, and low-cost substrates as carbon sources. By in-situ and ex-situ fermentation processes, metal/metal oxide nanoparticle composites are among the most widely used materials in diagnostic and regenerative medicine. The purpose of the review is to update the researchers regarding the lucid production process and versatile applications of bacterial nanocellulose in biomedical field. We shall mainly discuss about the different methods for bacterial cellulose production and some of its applications in this mini-review.

Bacterial nanocellulose and its application in heavy metals and dyes removal: a review.

This review discusses the application of bacterial nanocellulose (BNC) and modified BNC in treating wastewater containing heavy metals and dye contaminants. It also highlights the challenges and future perspectives of BNC and its composites. Untreated industrial effluents containing toxic heavy metals are systematically discharged into public waters. In particular, lead (Pb), copper (Cu), cadmium (Cd), nickel (Ni), zinc (Zn), and arsenic (As) are very harmful to human health and, in some cases, may lead to death. Several methods such as chemical precipitation, ion exchange, membrane filtration, coagulation, and Fenton oxidation are used to remove these heavy metals from the environment. However, these methods involve the use of numerous chemicals whilst producing high amount of toxic sludge. Meanwhile, the development of the adsorption-based technique has provided an alternative way of treating wastewater using BNC. Bacterial nanocellulose requires less energy for purification and has higher purity than plant cellulose. In general, the optimum growth parameters are crucial in BNC production. Even though native BNC can be used for the removal of heavy metals and dyes, the incorporation of other materials, such as polyethyleneimine, graphene oxide, calcium carbonate and polydopamine can improve sorption efficiencies.

Bacterial nanocellulose production using cost-effective, environmentally friendly, acid whey based approach

This study investigates the production of bacterial nanocellulose (BNC) film using a symbiotic culture of bacteria and yeasts (SCOBY) in acid whey medium. The yields were 59.58 g/L for wet and 2.75 g/L for freeze-dried BNC films in four days. The film contained cellulose nanofibrils with diameters ranging from 20 nm to 100 nm with a 34.3 % crystallinity index as confirmed by X-ray diffraction. Incorporating glycerol as a plasticizer modified the mechanical and thermal properties of the BNC film, reduced brittleness, and enhanced strain from 0.75 % to above 16 %. Fourier Transform Infrared Spectroscopy analysis identified intermolecular hydrogen bonding between the BNC film and glycerol. The glass transition temperature increased from roughly 158 °C to above 166 °C. The study validates the potential of acid whey as a viable alternative substrate for the production of BNC. The production method providing environmental benefits, cost-efficiency, and scalability, it also delivers an effective circular economy solution.

Use of brewer's residual yeast for production of bacterial nanocellulose with Gluconacetobacter hansenii

Bacterial nanocellulose (BNC) has attained elevated interest due to its versatile structure and high resistance characteristics. Accordingly, efforts have been made in order to reduce its production costs, such as the employment of its by-products as a nutrient broth to yield the microorganism. Residual brewer's yeast is an excellent recourse, due to its high nutritional value and availability. Therefore, research which aimed to contribute to the development of a low cost, efficient and biosustainable technology for BNC production with Gluconacetobacter hansenii was carried out. BNC was obtained from residual brewer's yeast hydrolysate at pH 7.0 and five days of incubation at 30 °C in static culture. The hydrolysate was characterized by the amount of sugars, fatty acids, total proteins and ash content. Subsequently, BNC obtained was characterized in terms of yield, carbon conversion ratio, hydrodynamic size, crystallinity, morphology, Fourier-transform infrared spectroscopy, and surface analysis. Residual brewer's yeast hydrolysate proved to be efficient in BNC production via gluconeogenesis with consumption of alanine, threonine and glycerol, obtaining 1.9 times the yield of the chemically defined broth adopted as standard. Additionally, properties observed in the obtained BNC were equal to those obtained from conventional chemical medium. The research contributed to bacterial nanocellulose production using by-products from the brewing industry.