Highest Bacterial Cellulose Yield Research Articles

Modification of microstructure and selected physicochemical properties of bacterial cellulose produced by bacterial isolate using hydrocolloid-fortified Hestrin-Schramm medium.

Bacterial cellulose (BC) is a biopolymer with applications in numerous industries such as food and pharmaceutical sectors. In this study, various hydrocolloids including modified starches (oxidized starch-1404 and hydroxypropyl starch-1440), locust bean gum, xanthan gum (XG), guar gum, and carboxymethyl cellulose were added to the Hestrin-Schramm medium to improve the production performance and microstructure of BC by Gluconacetobacter entanii isolated from coconut water. After 14-day fermentation, medium supplemented with 0.1% carboxymethyl cellulose and 0.1% XG resulted in the highest BC yield with dry BC content of 9.82 and 6.06 g/L, respectively. In addition, scanning electron microscopy showed that all modified films have the characteristic three-dimensional network of cellulose nanofibers with dense structure and low porosity as well as larger fiber size compared to control. X-ray diffraction indicated that BC fortified with carboxymethyl cellulose exhibited lower crystallinity while Fourier infrared spectroscopy showed characteristic peaks of both control and modified BC films.

Bioprocess development for bacterial cellulose biosynthesis by novel Lactiplantibacillus plantarum isolate along with characterization and antimicrobial assessment of fabricated membrane

Bacterial cellulose (BC) is an ecofriendly biopolymer with diverse commercial applications. Its use is limited by the capacity of bacterial production strains and cost of the medium. Mining for novel organisms with well-optimized growth conditions will be important for the adoption of BC. In this study, a novel BC-producing strain was isolated from rotten fruit samples and identified as Lactiplantibacillus plantarum from 16S rRNA sequencing. Culture conditions were optimized for supporting maximal BC production using one variable at a time, Plackett–Burman design, and Box Behnken design approaches. Results indicated that a modified Yamanaka medium supported the highest BC yield (2.7 g/l), and that yeast extract, MgSO4, and pH were the most significant variables influencing BC production. After optimizing the levels of these variables through Box Behnken design, BC yield was increased to 4.51 g/l. The drug delivery capacity of the produced BC membrane was evaluated through fabrication with sodium alginate and gentamycin antibiotic at four different concentrations. All membranes (normal and fabricated) were characterized by scanning electron microscope, Fourier transform-infrared spectroscopy, X-ray diffraction, and mechanical properties. The antimicrobial activity of prepared composites was evaluated by using six human pathogens and revealed potent antibacterial activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Streptococcus mutans, with no detected activity against Pseudomonas aeruginosa and Candida albicans.

In-situ fermentation with gellan gum adding to produce bacterial cellulose from traditional Chinese medicinal herb residues hydrolysate

In this study, bacterial cellulose was synthesized by Taonella mepensis from traditional Chinese medicinal herb residues hydrolysate. To overcome the inhibitory effect of fermentation environment, in-situ fermentation with gellan gum adding was carried out for the first time. After 10 days' static fermentation, both high-acyl gellan gum and low-acyl gellan gum adding showed certain beneficial effects for bacterial cellulose production that the highest bacterial cellulose yield (0.866 and 0.798 g/L, respectively) was 59% and 47% higher than that (0.543 g/L) without gellan gum adding. Besides, gellan gum based bacterial cellulose showed some better texture characteristics. Gellan gum was loaded in the nano network of bacterial cellulose, and gellan gum adding had some influence on the crystal structure and thermal degradation behaviors of bacterial cellulose but affected little on its functional groups. Overall, this in-situ fermentation technology is attractive for bacterial cellulose production from low-cost but inhibitory substrates.

Oil palm frond juice and coconut water as alternative fermentation substrate for bacterial cellulose production

Bacterial cellulose (BC) has emerged as an alternative and sustainable biomaterial due to its remarkable structural and mechanical properties, which can be used in various applications. BC is a form of biopolymer which far superior to its plants equivalent because of its high purity, high strength construction material, good mechanical strength, elasticity and high crystallinity. The research aims to produce BC using biological process synthesis of A. xylinum in oil palm frond juice (OPFJ) based medium. Oil palm frond (OPF) is Malaysia’s largest biomass produced from the oil palm plantation industry in Malaysia and contain fermentable sugar required to grow BC, glucose, sucrose and fructose. The experiment was conducted under optimum temperature 30 °C in static culture condition which were applied with different ratio of medium (Coconut water, OPFJ and distilled water). Our findings revealed that highest BC yield (4.50 g/L) was obtained in the mixture medium of OPFJ: Coconut water (60:40). FTIR analysis confirmed the pellicles as cellulosic material. FE-SEM analysis showed the ribbon network consisting of nanosize fibrils with diameter ranging from 50 to 60 nm. Overall, the work demonstrated the potential of producing high value-added polymer from OPFJ-based medium.

Characterization of Bacterial Cellulose Produced by Acetobacter xylinum Strain LKN6 Using Sago Liquid Waste as Nutrient Source.

<b>Background and Objective:</b> Bacterial Cellulose (BC) is an exopolysaccharide produced by bacteria with unique structural and mechanical properties and is highly pure compared to plant cellulose. This study aimed to produce novel bacterial cellulose using sago liquid waste substrate and evaluate its characteristics as a potential bioplastic.<b>Materials and Methods:</b> Production of BC by static batch fermentation was studied in sago liquid waste substrate usingAcetobacter xylinumLKN6. The BC structure was analyzed by Scanning Electron Microscopy (SEM) and Fourier Transform infrared spectroscopy (FT-IR). Mechanical properties were measured include tensile strength, elongation at break, elasticity (Young's modulus) and Water Holding Capacity (WHC). <b>Results:</b> The BC yield from sago liquid waste as a nutrients source was achieved 12.37 g L<sup>1</sup> and the highest BC yield 14.52 g L<sup>1</sup> in sago liquid waste medium with a sugar concentration of 10% (w/v) after 14 days fermentation period. The existence of bacterial cellulose is proven by FT-IR spectroscopy analysis based on the appearance of absorbance peaks, which are C-C bonding, C-O bonding, C-OH bonding and C-O-C bonding and represents the fingerprints of pure cellulose. The mechanical properties of BC from sago liquid waste were showed a tensile strength of 44.2-87.3 MPa, elongation at break of 4.8-5.8%, Young's Modulus of 0.86-1.64 GPa and water holding capacity of 85.9-98.6 g g<sup>1</sup>. <b>Conclusion:</b> The results suggest that sago liquid waste has great potential to use as a nutrient source in the production of bacterial cellulose and BC's prospect as the bioplastic.

Study of the influence of Medusomyces gisevii Sa-12 inoculum dosage on bacterial cellulose yield and degree of polymerisation

Bacterial cellulose (BC) consists in a highly crystalline nanopolymer whose potential for application in both traditional and new industries is significant due to its unique physico-mechanical properties. In scaled BC biosynthesis processes, the use of microorganism consortia characterised by their adaptability and synergistic effects when coordinating substrate consumption appears to be promising. In the present work, the effect of inoculum dosage on BC yield during Medusomyces gisevii Sa-12 symbiotic culture on a glucose medium under optimal conditions is studied in detail. Two available methods were chosen for quality control of the BC: scanning electron microscopy, presenting an express method for confirming the origin of cellulose; and the degree of polymerisation in terms of a common method for controlling the quality of cellulose. Four experiments were carried out for the producer introduction with a dosage of 5, 10, 15 and 20% vol.. Use of the Medusomyces gisevii Sa-12 symbiotic culture provided the greatest number of acetic acid bacteria and the highest BC yield (7.5–8.0%) with an inoculum dosage of 10–20% vol. At the same time, an inoculum dosage of 20% vol. allowed the culture time to be halved, while an inoculum dosage of 5% vol. appears to be insufficient. All inoculum dosage variants were determined to provide the same three-dimensional cross-linked microfibrillar structure of BC samples. The degree of polymerisation (DP) of BC samples was first established to depend on the dosage of the inoculum and the duration of BC biosynthesis. Thus, the biosynthesis process can be controlled using such a simple parameter as inoculum dosage and BCs can be synthesised directionally with a given DP. The inoculum dosage of 10% vol. was established as providing the highest possible DP of BC (value of 5000), decreasing slightly during prolonged culture.

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

In this study, a bacterial cellulose (BC) producing strain was isolated from Kombucha tea and identified as Komagataeibacter hansenii JR-02 by morphological, physiological, and biochemical characterization and 16S rRNA sequence. Then, the media components and culture conditions for BC production were optimized. Result showed that the highest BC yield was 3.14±0.22 and 8.36±0.19g/L after fermentation for 7 days under shaking and static cultivation, respectively. Moreover, it was interesting that JR-02 could produce BC in nitrogen-free medium with the highest yield of 0.76±0.06g/L/7days, and the possible nitrogen fixation gene nifH was cloned from its genomic DNA. The BC produced by JR-02 was type-I cellulose with high crystallinity and thermodynamic stability, which was revealed from Fourier transform infrared spectroscopy, X-ray diffraction, and thermogravimetric analysis methods. The crystallinity of static and shaking cultured BC were 91.76% and 90.69%, respectively. The maximum rate of weight loss of static and shaking BC occurred at temperature of approximately 373.1°C and 369.1°C, respectively. Overall, these results indicated that K. hansenii JR-02 had great potential to produce high crystallinity type-I BC in manufacture.

Efficient Using Durian Shell Hydrolysate as Low-Cost Substrate for Bacterial Cellulose Production by Gluconacetobacter xylinus.

Durian is one important tropical fruit with high nutritional value, but its shell is usually useless and considered as waste. To explore the efficient and high-value utilization of this agricultural and food waste, in this study, durian shell was simply hydrolyzed by dilute sulfuric acid, and the durian shell hydrolysate after detoxification was used for bacterial cellulose (BC) production by Gluconacetobacter xylinus for the first time. BC was synthesized in static culture for 10days and the highest BC yield (2.67g/L) was obtained at the 8th day. The typical carbon sources in the substrate including glucose, xylose, formic acid, acetic acid, etc. can be utilized by G. xylinus. The highest chemical oxygen demand (COD) removal (16.40%) was obtained at the 8th day. The highest BC yield on COD consumption and the highest BC yield on sugar consumption were 93.51% and 22.98% (w/w), respectively, suggesting this is one efficient bioconversion for BC production. Durian shell hydrolysate showed small influence on the BC structure by comparison with the structure of BC generated in traditional Hestrin-Schramm medium detected by FE-SEM, FTIR, and XRD. Overall, this technology can both solve the issue of waste durian shell and produce valuable bio-polymer (BC).

Efficient bioconversion from acid hydrolysate of waste oleaginous yeast biomass after microbial oil extraction to bacterial cellulose by Komagataeibacter xylinus

ABSTRACTBiomass acid hydrolysate of oleaginous yeast Trichosporon cutaneum after microbial oil extraction was applied as substrate for bacterial cellulose (BC) production by Komagataeibacter xylinus (also named as Gluconacetobacter xylinus previously) for the first time. BC was synthesized in static culture for 10 days, and the maximum BC yield (2.9 g/L) was got at the 4th day of fermentation. Most carbon sources in the substrate (glucose, mannose, formic acid, acetic acid) can be utilized by K. xylinus. The highest chemical oxygen demand (COD) removal (40.7 ± 3.0%) was obtained at the 6th day of fermentation, and then the COD increased possibly due to the degradation of BC. The highest BC yield on COD consumption was 38.7 ± 4.0% (w/w), suggesting that this is one efficient bioconversion for BC production. The BC structure was affected little by the substrate by comparison with that generated in classical HS medium using field-emission scanning electron microscope (FE-SEM), Fourier transform infrared, and X-ray diffraction. Overall, this technology can both solve the issue of waste oleaginous yeast biomass and produce valuable biopolymer (BC).

Comparison of bacterial cellulose production by Gluconacetobacter xylinus on bagasse acid and enzymatic hydrolysates

ABSTRACTTo fulfill the comprehensive utilization of cellulose and hemicellulose components in bagasse for bacterial cellulose (BC) production, both bagasse acid and enzymatic hydrolysates were used for BC production by Gluconacetobacter xylinus. Although the BC accumulation rate was slower during the early period of fermentation in the bagasse acid hydrolysate than in the enzymatic hydrolysate, the highest BC yield (1.09 vs. 0.42 g/L) was higher in the bagasse acid hydrolysate. The substrate utilization was evaluated in both bagasse acid and enzymatic hydrolysates, and glucose, xylose, and acetic acid were better carbon sources than arabinose and cellobiose for G. xylinus. The structure of the BC samples obtained from bagasse acid and enzymatic hydrolysates, including the microscopic morphology, functional groups, and crystals, was similar especially in the later phase of fermentation, which was analyzed by field emission scanning electron microscopy, Fourier transform infrared spectroscopy, and X‐ray diffraction. Thus, both bagasse acid and enzymatic hydrolysates could be promising substrates for BC production. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45066.

Phenotype of human chondrocytes growing in vitro on the surface of bionanocellulose

In this study, lipid fermentation wastewater (fermentation broth after separation with yeast biomass) with high Chemical Oxygen Demand (COD) value of 25,591 mg/L was used as substrate for bacterial cellulose (BC) production by Gluconacetobacter xylinus for the first time. After 5 days of fermentation, the highest BC yield (0.659 g/L) was obtained. Both monosaccharide and polysaccharides present in lipid fermentation wastewater could be utilized by G. xylinus simultaneously during fermentation. By this bioconversion, 30.0% of COD could be removed after 10 days of fermentation and the remaining wastewater could be used for further BC fermentation. The crystallinity of BC samples in lipid fermentation wastewater increased gradually during fermentation but overall the environment of lipid fermentation wastewater showed small influence on BC structure by comparison with that in traditional HS medium by using FE-SEM, FTIR, and XRD. By this work, the possibility of using lipid fermentation wastewater containing low value carbohydrate polymer (extracellular polysaccharides) for high value carbohydrate polymer (BC) production was proven.

Using wastewater after lipid fermentation as substrate for bacterial cellulose production by Gluconacetobacter xylinus

In this study, lipid fermentation wastewater (fermentation broth after separation with yeast biomass) with high Chemical Oxygen Demand (COD) value of 25,591mg/L was used as substrate for bacterial cellulose (BC) production by Gluconacetobacter xylinus for the first time. After 5 days of fermentation, the highest BC yield (0.659g/L) was obtained. Both monosaccharide and polysaccharides present in lipid fermentation wastewater could be utilized by G. xylinus simultaneously during fermentation. By this bioconversion, 30.0% of COD could be removed after 10 days of fermentation and the remaining wastewater could be used for further BC fermentation. The crystallinity of BC samples in lipid fermentation wastewater increased gradually during fermentation but overall the environment of lipid fermentation wastewater showed small influence on BC structure by comparison with that in traditional HS medium by using FE-SEM, FTIR, and XRD. By this work, the possibility of using lipid fermentation wastewater containing low value carbohydrate polymer (extracellular polysaccharides) for high value carbohydrate polymer (BC) production was proven.

Evaluating the possibility of using acetone-butanol-ethanol (ABE) fermentation wastewater for bacterial cellulose production by Gluconacetobacter xylinus.

To reduce the cost of bacterial cellulose (BC) production, the possibility of using acetone-butanol-ethanol (ABE) fermentation wastewater with high COD value (18050mgl(-1) ) for BC production by Gluconacetobacter xylinus was evaluated. After 7days of fermentation, the highest BC yield (1·34gl(-1) ) was obtained. The carbon sources including sugars (glucose and xylose), organic acids (acetic acid and butyric acid) and alcohol compounds (ethanol and butanol) were utilized by G.xylinus simultaneously during fermentation. Although the COD decrease ratio (about 14·7%) was low, the highest BC yield on COD consumption (56·2%, gg(-1) ) was relatively high and the remaining wastewater could be used for further BC fermentation. Besides, the environment of ABE fermentation wastewater showed small influence on the BC structure by comparison with the BC products obtained in traditional HS medium using field emission scanning electron microscope (FE-SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Overall, ABE fermentation wastewater is one promising substrate for BC production. The possibility of using acetone-butanol-ethanol (ABE) fermentation wastewater for bacterial cellulose (BC) production by Gluconacetobacter xylinus was evaluated in this study. This is the first time that ABE fermentation wastewater was used as substrate for BC fermentation. The results provide detail information of metabolism of G.xylinus in ABE fermentation wastewater and the influence of wastewater environment on the structure of BC samples. Overall, this bioconversion could reduce the cost of BC production greatly.

Beneficial Effect of Acetic Acid on the Xylose Utilization and Bacterial Cellulose Production by Gluconacetobacter xylinus.

In this work, acetic acid was found as one promising substrate to improve xylose utilization by Gluconacetobacter xylinus CH001. Also, with the help of adding acetic acid into medium, the bacterial cellulose (BC) production by G. xylinus was increased significantly. In the medium containing 3gl(-1) acetic acid, the optimal xylose concentration for BC production was 20gl(-1). In the medium containing 20gl(-1) xylose, the xylose utilization and BC production by G. xylinus were stimulated by acetic acid within certain concentration. The highest BC yield (1.35±0.06gl(-1)) was obtained in the medium containing 20gl(-1) xylose and 3gl(-1) acetic acid after 14days. This value was 6.17-fold higher than the yield (0.21±0.01gl(-1)) in the medium only containing 20gl(-1) xylose. The results analyzed by FE-SEM, FTIR, and XRD showed that acetic acid affected little on the microscopic morphology and physicochemical characteristics of BC. Base on the phenomenon observed, lignocellulosic acid hydrolysates (xylose and acetic acid are main carbon sources present in it) could be considered as one potential substrate for BC production.

Bacterial cellulose production under oxygen-enriched air at different fructose concentrations in a 50-liter, internal-loop airlift reactor.

Bacterial cellulose (BC) production by Acetobacter xylinum subsp. sucrofermentans BPR2001 was carried out in a 50-1 internal-loop airlift reactor in air at an initial fructose concentration of 40 g/l. The BC production rate was 0.059 g/l per h. When oxygen-enriched air was supplied instead of air, the BC production rate increased to 0.093 g/l per h, and the BC yield was enhanced from 11% in air to 18%. When the initial fructose concentrations were varied from 30 to 70 g/l, the highest BC yield (35%) the highest production rate (0.22 g/l x per h), and the highest concentration of BC produced (10.4 g/l) were observed at 60-70 g/l fructose. From the carbon mass balance calculated at the final stage of cultivation, it was observed that enhanced BC production was reflected as a decrease in both CO2 evolution and the concentration of other unknown substances, suggesting the efficient utilization of energy for BC synthesis despite O2 limitation.