Cellulose Pellicles Research Articles

Screening of microbial population in Sabah tea kombucha pellicle for its potential as prebiotic and probiotic supplement

This research aimed to determine and analyze the microbial population in kombucha pellicles derived from Sabah black tea, specifically focusing on bacteria and yeast, to gain insights into their abundance, diversity, and potential as prebiotic and probiotic supplements. Despite the growing interest in kombucha in Malaysia, the specific microbial composition of the pellicle from locally sourced Sabah black teas remains underexplored. Understanding this composition could reveal its potential as a sustainable source of health-promoting microbes. It is hypothesized that Sabah tea kombucha pellicle harbours a beneficial microbial population that can be utilized as a low-cost prebiotic and probiotic supplements. The kombucha pellicle was prepared using 10 g of Sabah black tea, 1 L of sterile water containing 10% sugar (w/v), and a 10% kombucha symbiotic culture of bacteria and yeast (SCOBY). The process included boiling black tea with sugar, adding SCOBY culture, and allowing fermentation for 30 days to obtain cellulosic pellicles. After fermentation, the pellicle was separated, homogenized, and stored for further use. Then, kombucha pellicle genomic DNA was extracted and subjected to 16S and ITS metagenomic analysis to identify the bacteria and fungi population. The 16S and ITS metagenomic results showed that Sabah tea kombucha pellicle contains a potentially beneficial microbial population, mainly Komagataeibacter, Zygosaccharomyces and Starmerella, that may serve as a sustainable probiotic. This current study provides promising evidence for using Sabah tea kombucha pellicle as a low-cost prebiotic and probiotic supplement. This will indirectly help advertise and commercialize Sabah tea as one of the local products in Sabah.

Human Skeletal Muscle Myoblast Culture in Aligned Bacterial Nanocellulose and Commercial Matrices.

Bacterial nanocellulose (BNC) is a durable, flexible, and dynamic biomaterial capable of serving a wide variety of fields, sectors, and applications within biotechnology, healthcare, electronics, agriculture, fashion, and others. BNC is produced spontaneously in carbohydrate-rich bacterial culture media, forming a cellulosic pellicle via a nanonetwork of fibrils extruded from certain genera. Herein, we demonstrate engineering BNC-based scaffolds with tunable physical and mechanical properties through postprocessing. Human skeletal muscle myoblasts (HSMMs) were cultured on these scaffolds, and in vitro electrical stimulation was applied to promote cellular function for tissue engineering applications. We compared physiologic maturation markers of human skeletal muscle myoblast development using a 2.5-dimensional culture paradigm in fabricated BNC scaffolds, compared to two-dimensional (2D) controls. We demonstrate that the culture of human skeletal muscle myoblasts on BNC scaffolds developed under electrical stimulation produced highly aligned, physiologic morphology of human skeletal muscle myofibers compared to unstimulated BNC and standard 2D culture. Furthermore, we compared an array of metrics to assess the BNC scaffold in a rigorous head-to-head study with commercially available, clinically approved matrices, Kerecis Omega3 Wound Matrix (Marigen) and Phoenix as well as a gelatin methacryloyl (GelMA) hydrogel. The BNC scaffold outcompeted industry standard matrices as well as a 20% GelMA hydrogel in durability and sustained the support of human skeletal muscle myoblasts in vitro. This work offers a robust demonstration of BNC scaffold cytocompatibility with human skeletal muscle cells and sets the basis for future work in healthcare, bioengineering, and medical implant technological development.

Plausible Avenues and Applications of Bioformulations from Symbiotic Culture of Bacteria and Yeast

Microbial cellulose, especially the bacterial cellulose produced by symbiotic co-cultures of acetic acid bacteria and yeast (SCOBY) that exists in a mutualistic interaction opens plausible strategies in the field of food as well as sustainable regenerative eco-system and waste management. Cultivated on sweetened black tea, the mutually proliferating bacteria (Acetobacter xylinum, A. xylinoides, and Bacterium gluconicum) and yeast strains (Schizosaccharomyces pombe, Saccharomycodes ludwigii and Saccharomyces cerevisiae) produces a fermented liquor along with the floating bacterial cellulosic pellicle called as Kombucha. This review explores the possible applications of kombucha SCOBY to use bacterial cellulose-based engineered living materials, commercial superabsorbent spheres by various marketing ventures like food, pharmaceutics, biomedical applications for bio-sensing and bio-catalysis, crop biostimulants, biocontrol agents in the management of plant and animal illnesses, post-harvest management in crops, water purification, pollutant detection, environmental biotechnology, and production of SCOBY from alternative substrates and agrarian waste management. The plausible use of bacterial cellulose hydrogels in dryland agriculture for their exceptional water-absorbing capability, eco-friendly nature, capacity to break down naturally, and compatibility with other living organisms is also elaborated in this paper. Furthermore, diverse microbial species to enhance the variety and functional properties of SCOBY, health benefits and its influence on human welfare is vividly discussed in the paper. The very in-depth study on the uses of SCOBY also paves way for the research exploration of this under-utilized microbial boon in food and farm sector for circular based regenerative agriculture in near future.

Bacterial cellulose with CHAPK-mediated specific antimicrobial activity against Staphylococcus aureus

Wound healing represents a complex biological process often hampered by bacterial infections, in particular those caused by Staphylococcus aureus, which is already multiresistant to many antibiotics. In this sense, enzybiotics have additional advantages over conventional antibiotics, since they provide pathogen specificity and do not contribute to antibiotic resistance. However, their soluble administration at the wound site would result in enzyme leakage. On the other hand, bacterial cellulose (BC) pellicles present a very promising dressing and scaffold, given its high purity, water retention capacity, and barrier effect in the wound against possible contaminants. In this study, we present a novel approach that incorporates the enzybiotic CHAPK into BC to develop functionalized membranes that exhibit targeted and controlled antimicrobial activity against S. aureus. The kinetic tests revealed a continuous loading of the enzybiotic into BC until it reaches a maximum and a two-stage release process, characterized by an initial fast release followed by a sustained release. Attenuated total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM), and Confocal Laser Scanning Microscopy (CLSM) confirmed the incorporation and the preferential surface localization of CHAPK within the BC membranes. Finally, the BC/CHAPK materials demonstrated the sustained reduction of up to 4 logarithmic units in the viability of S. aureus. Overall, the biomaterials developed here exhibit promising antimicrobial efficacy against S. aureus, offering a potential strategy for wound management and skin infection control while maintaining unharmed the commensal skin microbiota, which impairment could compromise the integrity of the skin barrier function.

Probiotic potential of acetic acid bacteria isolated from kombucha in New Zealand in vitro

Kombucha is a fermented tea beverage containing live microorganisms, mostly beneficial strains of yeast and acetic acid bacteria (AAB), but empirical evidence is limited supporting the probiotic potential of kombucha. This study reports the in vitro probiotic potential of 36 AAB strains isolated from three Kombucha samples commercially available in New Zealand. Nine representative AAB strains, belonging to three species (Komagataeibacter rhaeticus, Acetobacter musti and Gluconobacter potus), were examined for their primary probiotic characteristics such as tolerance to bile salts, NaCl, and low pH, and temperature. Three non-cellulose forming strains (A. musti LOAAB1, G. potus LOAAB2 and G. potus GBAAB3) were assayed for their cell surface characteristics such as auto-aggregation, co-aggregation with pathogenic bacteria, and hydrophobicity. Antimicrobial, antioxidant activities and enzymatic activities were also investigated for the strains of interest. Results indicated that nine strains were able to grow under low pH in the presence of bile salts, suggesting their potential to survive in the human gut. Six K. rhaeticus strains produced cellulosic pellicles, a potential source of prebiotics for beneficial bacteria. The three AAB strains LOAAB1, LOAAB2 and GBAAB3 showed promising cell surface characteristics, such as auto-aggregation rates (>80 %), co-aggregation with four pathogenic bacteria (13.24–43.47 %), hydrophobicity (42.12 % to 50.20 %), and antioxidant activities (>90 %). All nine strains tested negative for enzymatic activities (haemolytic, proteolytic, phospholipase, and gelatinase), suggesting that they are safe to consume. Together, these data indicate the potential for the three AAB strains to be further investigated as probiotic sources with more in vivo tests for applications in the food and beverages industry.

Nata De Coco Quality Development Model from Different Inoculum Sources

The results of the study "Nata De Coco Quality Development Model from Different Inoculum Sources", aim (1) to utilize wasted coconut water from the coconut industry and home industry, (2) to obtain a Nata de Coco quality development model from different inoculum sources (inoculum from pineapple flesh and inoculum that are already available on the market. The methodology used is quantitative (laboratory experiments) with Complete Randomized Design (RAL). This research includes stages, as follows, namely: Phase I, using coconut water media sources with the maturity level of ripe coconuts, with Treatment A = basic ingredients of fresh Coconut Water (0 storage), B = basic ingredients of Coconut Water with storage for 1 week, C = basic ingredients of coconut water with storage for 2 weeks, and treatment D = basic ingredients of coconut water with storage for 3 weeks. Phase II, fermenting coconut water which becomes a substrate as a fermentation medium using inoculum sources, namely: liquid inoculum sources from natural ingredients of pineapple flesh and liquid inoculum sources available on the market in producing cellulose pellicle. The results of the study can be concluded as follows: (1) Coconut water waste wasted from the coconut industry and coconut home industry in the North Minahasa Regency area of North Sulawesi from ripe coconuts can be utilized by Acetobacter xylinum bacteria in producing Nata de Coco pellicle, (2) IN treatment (Natural Acetobacter xylinum liquid inoculum from pineapple fruit) provides the best treatment results from several quality parameters of Nata de Coco produced such as: parameters of Layer Thickness, Water Content, Fiber Content, and Color, than IP treatment (liquid inoculum Acetobacter xylinum on the market).

Simultaneous use of two-step fermentation and in-situ addition of chitosan oligosaccharide improving bacterial cellulose pellicle in the synthesis and various behaviors

Simultaneous use of two-step fermentation and in-situ addition of chitosan oligosaccharide improving bacterial cellulose pellicle in the synthesis and various behaviors

Tea Fungus Beverages from Torch Ginger (Etlingera elatior): Total microbial, Physicochemical, and Antioxidant Activity

Functional beverages are needed to maintain health and fitness as a part of the instant lifestyle and degenerative diseases. The scientific findings on torch ginger (Etlingera elatior) flower (TGF) as a tea fungus beverage (Kombucha) are still limited. This research evaluated total microbes, physicochemical properties, and antioxidant activity 7 and 14 days after fermentation (daf) of TGF kombuchas. In addition, TGF in variant 0% (TGF0), 5% (TGF5), 10% (TGF10), and 15% (TGF15) are fermented with 3% of SCOBY, 20% culture, 1% green tea, and 10% sucrose. The antioxidant activities of TGF kombuchas were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-Azino-bis 3-Ethylbenzothiazoline-6-Sulfonic Acid (ABTS) assay—the phenolic and flavonoid content using Folin-Ciocalteu method-gallic acid equivalent, and quercetin acid equivalent, respectively. The result showed that the fermentation time (p0.05) was affected by the properties of TGF kombuchas. Total microbes, physicochemical properties (pH, acidity, cellulose pellicle weight, phenolic, flavonoid content), and antioxidant activity were higher in 14 than in 7 days. Total soluble solid and total yeast count showed lower values in 14 days. The increase in total bacteria count, TGF15%, led to the highest increasing density from 8.08 ± 0.02Log CFU/mL on seven daf to 13.34 ± 0.04Log CFU/mL on 14 daf. The TGF 10% and 15% kombuchas in 14 dafs showed abundance in phenolic and flavonoid content, 121.45±1.07mg GAE/mL and 1.70±0.04 mg QAE/mL, respectively. During 14 daf and TGF 10%, the Kombucha of torch ginger flower demonstrated high antioxidant activity at 85.92±0.07% DDPH and 63.05±0.97ABTS. It is expected to aid future research into developing functional kombucha beverages.

Microbiological and Physico-Chemical Characteristics of Black Tea Kombucha Fermented with a New Zealand Starter Culture.

Kombucha is a popular sparkling sugared tea, fermented by a symbiotic culture of acetic acid bacteria (AAB) and yeast. The demand for kombucha continues to increase worldwide, mainly due to its perceived health benefits and appealing sensory properties. This study isolated and characterised the dominant AAB and yeast from a starter culture and kombucha broth after 0, 1, 3, 5, 7, 9, 11, and 14 days of fermentation at ambient temperature (22 °C). Yeast and AAB were isolated from the Kombucha samples using glucose yeast extract mannitol ethanol acetic acid (GYMEA) and yeast extract glucose chloramphenicol (YGC) media, respectively. The phenotypic and taxonomic identification of AAB and yeast were determined by morphological and biochemical characterisation, followed by a sequence analysis of the ribosomal RNA gene (16S rRNA for AAB and ITS for yeast). The changes in the microbial composition were associated with variations in the physico-chemical characteristics of kombucha tea, such as pH, titratable acidity, and total soluble solids (TSS). During fermentation, the acidity increased and the TSS decreased. The yield, moisture content, and water activity of the cellulosic pellicles which had developed at the end of fermentation were attributed to the presence of AAB. The dominant AAB species in the cellulosic pellicles and kombucha broth were identified as Komagataeibacter rhaeticus. The yeast isolates belonged to Debaryomyces prosopidis and Zygosaccharomyces lentus.

The production and characterization of bacterial cellulose pellicles obtained from oil palm frond juice and their conversion to nanofibrillated cellulose

This study explored the potential of using oil palm frond (OPF) juice as a fermentation medium for bacterial cellulose (BC) synthesis by Acetobacter xylinum 0416, followed by its conversion into nanofibrillated cellulose (BNFC). The effect of adding nitrogen sources to OPF juice on the BC yield and thickness was investigated, with corn steep liquor (CSL) showing the most promising results, increasing BC yield and thickness by six- and four-fold, respectively. The resulting BC-OPF+CSL pellicles demonstrated excellent thermal stability, high crystallinity and a large swelling ratio. The study also investigated the conversion of BC-OPF+CSL pellicles into BNFC using either homogenization, ultrasonication, or a combination of both. The combination of ultrasonication and homogenization produced the best results, disintegrating the BC fibers into BNFC with a diameter of 13–21 nm and water retention value of 6105%. Low BNFC crystallinity and thermal stability were also observed, indicating successful BC fibrillation. These findings suggest that OPF juice is a promising alternative fermentation medium for BC production and that combining ultrasonication and homogenization is a simple and safe method for converting BC-OPF+CSL pellicles into BNFC. This research offers a potential eco-friendly solution for BC production and its conversion into value-added products such as BNFC.

In situ visualization of the tensile deformation mechanism of bacterial cellulose network

Bacterial cellulose (BC) pellicles are strong hydrogels composed of nanofibril networks. These hydrogels are considered attractive materials for synthetic biology, in which biological systems or modules are designed with user-defined functions. To develop BC-based materials with tailored mechanical properties, elucidation of the tensile deformation mechanism is essential. Therefore, in this study, BC hydrogels were fluorescently labeled, and the fiber network under tensile deformation was observed in situ using a device for simultaneous confocal laser scanning microscopy and uniaxial tensile deformation. As a result, strain-dependent deformation modes were identified and the generation of stress paths (stress-loaded fiber segments) during deformation was visualized. Furthermore, characteristic relaxation spectra of the nanofiber network were obtained from stress-relaxation measurements, revealing the existence of a first-order relaxation mode at approximately 1 s and higher-order relaxation modes over a long time period of 102–105 s. On this basis, we proposed a tensile deformation model of the BC hydrogel characterized by rearrangements of fiber segments accompanied by cleavage of cross-links. This model is expected to facilitate synthetic biology using BC hydrogels.

Bio-inspired fabrication of adsorptive ultrafiltration membrane for water purification: Simultaneous removal of natural organic matters, lead ion and organic dyes

Conventional ultrafiltration membrane is difficult to achieve the multi-component removal of water contaminants including macromolecules and small ions. Meanwhile, a large number of petrochemical-based polymers as membrane material is raising concerns about environmental risk. In this study, we present a feasible way for the manufacture of multifunctional cellulose-based nanocomposite membranes via bio-fabrication by Acetobacter xylinus for water purification. The harvested bacterial cellulose (BC) pellicle was coated by polydopamine (PDA) as a functional layer and molecular linker to immobilize carboxylated cellulose nanocrystals (C-CNCs) to prepare BC/PDA14h/CNCs membrane (BCM/PDA14h/CNCs). The composited PDA and C-CNCs on the BC nanofibers endowed the membrane with a maximum adsorption capacity of up to 167.80 mg g−1 for Pb2+, and 251.58 mg g−1 for methylene blue (MB). Multiple contaminants (heavy metals, organic dyes, and natural organic matter (NOM)) can also be treated by BCM/PDA14h/CNCs simultaneously during the dynamic filtration process. The removal efficiency of BCM/PDA14h/CNCs against the mixture of metal ions is inversely proportional to the radius of hydrated ions. The selective separation studies on binary dye mixtures showed that the separation efficiency of the membrane is mainly related to the electronegativity of dyes. The BCM/PDA14h/CNCs exhibited preferential adsorption for cationic dyes, with a separation efficiency was up to 98%. Dynamic fouling experiments confirmed that the BCM/PDA14h/CNCs presented excellent antifouling performance and showed a high flux recovery ratio. The multifunctional characteristic, high removal efficiency, excellent reusability and stability as well as environmentally friendly feature of the prepared membrane in the present study provide a sustainable approach for membrane fabrication and promising application in water purification.

Analysis of cellulose synthesis in a high-producing acetic acid bacterium Komagataeibacter hansenii

Bacterial cellulose (BC) represents a renewable biomaterial with unique properties promising for biotechnology and biomedicine. Komagataeibacter hansenii ATCC 53,582 is a well-characterized high-yield producer of BC used in the industry. Its genome encodes three distinct cellulose synthases (CS), bcsAB1, bcsAB2, and bcsAB3, which together with genes for accessory proteins are organized in operons of different complexity. The genetic foundation of its high cellulose-producing phenotype was investigated by constructing chromosomal in-frame deletions of the CSs and of two predicted regulatory diguanylate cyclases (DGC), dgcA and dgcB. Proteomic characterization suggested that BcsAB1 was the decisive CS because of its high expression and its exclusive contribution to the formation of microcrystalline cellulose. BcsAB2 showed a lower expression level but contributes significantly to the tensile strength of BC and alters fiber diameter significantly as judged by scanning electron microscopy. Nevertheless, no distinct extracellular polymeric substance (EPS) from this operon was identified after static cultivation. Although transcription of bcsAB3 was observed, expression of the protein was below the detection limit of proteome analysis. Alike BcsAB2, deletion of BcsAB3 resulted in a visible reduction of the cellulose fiber diameter. The high abundance of BcsD and the accessory proteins CmcAx, CcpAx, and BglxA emphasizes their importance for the proper formation of the cellulosic network. Characterization of deletion mutants lacking the DGC genes dgcA and dgcB suggests a new regulatory mechanism of cellulose synthesis and cell motility in K. hansenii ATCC 53,582. Our findings form the basis for rational tailoring of the characteristics of BC.Key points• BcsAB1 induces formation of microcrystalline cellulose fibers.• Modifications by BcsAB2 and BcsAB3 alter diameter of cellulose fibers.• Complex regulatory network of DGCs on cellulose pellicle formation and motility.

Comparing the filtering efficiency of kombucha SCOBY and nitrocellulose membrane filter

Kombucha is a fermented tea made from tea broth 5-8% Sucrose (granulated sugar) and SCOBY (symbiotic culture of bacteria and yeast), it is an alcoholic drink with 0.5 -2.5% alcohol. The origin of kombucha tea is said to be from China. The kombucha tea takes about 7-10 days for its fermentation. The fermentation takes place in two stages, wherein the first stage takes about 7-10 days, and the pellicle is formed in the air-water interface and in the second stage the flavoring of the kombucha is done with the fruit pulp and it is left for 10 days. In the first stage of fermentation, it forms a polymeric cellulose pellicle (SCOBY) with the help of certain species of bacteria and yeast-like lactic acid bacteria, Acetic acid bacteria and Saccharomyces species. The consumption of kombucha is good for health. The SCOBY is a biofilm formed by the action of acetic acid bacteria, lactic acid bacteria, and yeast and it is made of cellulose polymeric compound which can trap the microorganisms to a certain extent and retain them on the filter pad (SCOBY). The increased use of nitrocellulose membrane filter is used for filtering microorganisms from the sample is used extensively as it gives out efficient results, but the continuous and increased use of nitrocellulose filter is not good for the environment and for the human population who live near the industries where it is made. This study focuses on the use of SCOBY as a filter pad on various samples and finding out its efficiency when compared to the nitrocellulose membrane filter pad.

Kombucha: Production and Microbiological Research.

Kombucha is a sparkling sugared tea commonly prepared using a sugared tea infusion and fermented at ambient temperature for several days using a cellulose pellicle also called tea fungus that is comprised of acetic acid bacteria and yeast. Consumption of Kombucha has been reported as early as 220 B.C. with various reported potential health benefits and appealing sensory properties. During Kombucha fermentation, sucrose is hydrolysed by yeast cells into fructose and glucose, which are then metabolised to ethanol. The ethanol is then oxidised by acetic acid bacteria (AAB) to produce acetic acid which is responsible for the reduction of the pH and also contributes to the sour taste of Kombucha. Characterisation of the AAB and yeast in the Kombucha starter culture can provide a better understanding of the fermentation process. This knowledge can potentially aid in the production of higher quality products as these microorganisms affect the production of metabolites such as organic acids which are associated with potential health benefits, as well as sensory properties. This review presents recent advances in the isolation, enumeration, biochemical characteristics, conventional phenotypic identification system, and modern genetic identification techniques of AAB and yeast present in Kombucha to gain a better understanding of the microbial diversity of the beverage.

Structural and mechanical anisotropy in rheotactically aligned bacterial cellulose

In this work, we demonstrate the preparation of oriented bacterial cellulose from Komagataeibacter sucrofermentans by rheotactic growth in a simple and adaptable setup. The resulting materials were assessed by their yields, geometric densities, and by X-ray diffraction, scanning electron and optical microscopy, and mechanical testing. They exhibited large differences in toughness, resulting from differences in fracture strain or highly anisotropic strengths. Their growth characteristics, structural and mechanical anisotropies and crystalline phase characteristics are discussed and compared to statically grown references and to instances from the literature. Here, we consider the length scales of structural anisotropy in native bacterial cellulose pellicles, and the origin of mechanical anisotropy. Further, we identify a tentative limit on achievable structural alignment in bacterial cellulose, as well as a correlation between crystallinity and disorder in the crystalline phase of bacterial cellulose.

Biomineralization of Symbiotic Cultures of Bacteria and Yeast (SCOBY) Cellulose Aerogels

Microbial biomineralization is explored as a strategy for improving the thermal stability of symbiotic cultures of bacteria and yeast (SCOBY) cellulose aerogels. Cellulose pellicles were grown in kombucha tea and subsequently biomineralized with Sporosarcina pasteurii (S. pasteurii). The samples were exposed to one, two, or three cycles of ureolytic biomineralization. The microstructure and material properties of biomineralized samples were compared to experimental controls, which included a non‐biomineralized cellulose aerogel sample and an abiotic cellulose aerogel sample that was exposed to the biomineralization treatment without the addition of S. pasteurii. Results indicate that significant biomineralization (up to 38% CaCO3 by mass) occurred in the biomineralized SCOBY cellulose aerogels. Multiple biomineralization cycles enhance biomineralization of the sample surface and interior. Thermal conductivities of resultant aerogels measured ≈0.043–0.057 Wm−1 K−1 for all samples, indicating that biomineralization did not negatively affect the thermal conductivity of the SCOBY cellulose aerogels. Results further illustrate that biomineralization improved the thermal stability and flame resistance of SCOBY cellulose aerogels compared to experimental controls. Low thermal conductivity, improved thermal stability, and higher flame resistance of biomineralized SCOBY cellulose aerogels together indicate that thermally stable insulation materials can be produced exclusively from biological organisms.

Effect of Homogenization Pressure on Bacterial Cellulose Membrane Characteristic Made from Pineapple Peel Waste

Many studies were conducted to maintain the environment by reducing the waste, especially pineapple peel waste. This study aims to explore the effect of various pressure of the homogenization process on bacterial cellulose membrane surface morphology and structure produced using extract of pineapple peel waste. The methods include the preparation of pellicle samples from the product of the fermentation process of Acetobacter xylinum using a medium from the extract of pineapple peel waste. Bacterial cellulose pellicles were crushed using a blender. Mashed bacterial cellulose pellicle then homogenized in High-Pressure Homogenizer with pressure variation of 0 bar, 150 bar, 300 bar, 450 bar, dan 600 bar then cast into a mold. The bacterial cellulose solutions were dried in an oven at 60°C for 8 hours. The dried bacterial cellulose membrane was analyzed using XRD for the structure and SEM analysis for the morphology. The results indicate that the crystalline properties of BCM were shifted after being treated by various pressure processing in a High-Pressure Homogenizer. It was found that the High-Pressure Homogenizer with higher pressure reduced the peak intensity, decreased crystalline index from 87% to 70%, and decreased the degree of crystalline from 88% to 77% without changing the cellulose structure. The higher pressure of the homogenization process causes the porosity of the membrane to be decreased.

Reproducibility of Bacterial Cellulose Nanofibers Over Sub-Cultured Generations for the Development of Novel Textiles.

The textile industry is in crisis and under pressure to minimize the environmental impact on its practices. Bacterial cellulose (BC), a naturally occurring form of cellulose, displays properties superior to those of its cotton plant counterpart, such as enhanced purity, crystallinity, tensile strength, and water retention and is thus suitable for an array of textile applications. It is synthesized from a variety of microorganisms but is produced in most abundance by Komagataeibacter xylinus. K. xylinus is available as a type strain culture and exists in the microbial consortium commonly known as Kombucha. Whilst existing literature studies have described the effectiveness of both K. xylinus isolates and Kombucha in the production of BC, this study investigated the change in microbial communities across several generations of sub-culturing and the impact of these communities on BC yield. Using Kombucha and the single isolate strain K. xylinus as inocula in Hestrin and Schramm liquid growth media, BC pellicles were propagated. The resulting pellicles and residual liquid media were used to further inoculate fresh liquid media, and this process was repeated over three generations. For each generation, the thickness of the pellicles and their appearance under SEM were recorded. 16S rRNA sequencing was conducted on both pellicles and liquid media samples to assess changes in communities. The results indicated that the genus Komagataeibacter was the most abundant species in all samples. Cultures seeded with Kombucha yielded thicker cellulose pellicles than those seeded with K. xylinus, but all the pellicles had similar nanofibrillar structures, with a mix of liquid and pellicle inocula producing the best yield of BC after three generations of sub-culturing. Therefore, Kombucha starter cultures produce BC pellicles which are more reproducible across generations than those created from pure isolates of K. xylinus and could provide a reproducible sustainable model for generating textile materials.

Characterization of Nanocomposite Membrane Based Bacterial Cellulose Made of Pineapple Waste Reinforced by Graphite Nanoplatelets

Waste is the main problem for the environment. Handling waste for various useful applications has a benefit for the future. This work has been studied for handling pineapple peel waste to make composite film bacterial cellulose nanocomposite membrane (BCNM) with addition graphite nanoplatelet (GNP). The concentration of GNP in the membrane influence the membrane properties. The bacterial cellulose (BC) pellicle was synthesized by using media from pineapple peel waste extract. BC pellicle is cleaned with water and NaOH solution to be free from impactors. BCNM is synthesized through the mechanical disintegration stage. The results of disintegration using high pressure homogenizer at 150 bar and five cycles. BCNM/GNP is synthesized with varying addition of GNP of 2.5, 5.0, 10 and 100 wt% of dry bacterial nanocellulose (BNC). The BC and GNP solution were dried in an oven for 14 h at 80°C. BCNM morphology was observed using SEM. GNP is dispersed and distributed in the BC matrix as reinforcement. FTIR analysis shows many peaks of BNC less pronounced with increasing of GNP. The higher concentration of GNP, the rougher of BCNM. The optimum tensile strength of BCNM was achieved after addition GNP of 2.5 wt%.