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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. [ABSTRACT FROM AUTHOR]

BACKGROUND: Bacterial cellulose (BC) is a fiber substance produced by microbial fermentation. It is widely used in the food preservation industry because of its extremely pure texture, high crystallinity and high biocompatibility. In the present study, bacterial cellulose/thyme essential oil (BC/TEO‐E) with antibacterial and fresh‐keeping functions was prepared by ultrasonic treatment of modified bacterial cellulose for encapsulation of thyme essential oil, which effectively inhibited the spoilage of chilled chicken. RESULTS: The purified BC, produced by Acetobacter xylinum ATCC 53524, was ultrasonically treated wih different times (0, 30, 60 and 90 min). Transmission electron microscopy, scanning electron microscopy, Fourier transformed infrared spectroscopy, X‐ray diffraction, differential scanning calorimetry and zeta potential were used to characterize the structure of BC after ultrasound, showing that BC, treated for 30 min, had the optimal fiber structure, crystallinity (85.8%), thermal stability (347.77 °C) and solution stability (−26.63 ± 1.96 mV). BC/TEO‐E was prepared by a homogenizer for the preservation of chilled chicken. Optical microscopy indicated that the BC/TEO‐E prepared by 0.5% BC had optimal dispersion and stability, and even no delamination was observed in the emulsion. Compared with other groups (control, 0.5% BC and Tween‐E), the total number of colonies and coliforms in chilled chicken treated with 0.5% BC/TEO‐E was the lowest during the whole storage period (12 days), indicating that it can effectively inhibit bacterial growth. In addition, total volatile base nitrogen (TVB‐N), thiobarbituric acid reactive substances, pH and drip loss results showed that 0.5% BC/TEO‐E could effectively inhibit the spoilage of chilled chicken compared to the other treatment groups. CONCLUSION: All of the results acquired in the present study indicate that BC/TEO‐E has a potential application in chilled chicken preservation. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this study, a cost‐effective complex culture media containing molasses and corn steep liquor (CSL) was developed for the high production of bacterial cellulose (BC) by investigating the effect of four effective factors on BC production at three levels using Taguchi and combined methods. The predicted and actual values of BC production in optimal conditions by Taguchi and combined methods were 8.41 and 14.52 g/L, respectively. These results showed that the combined method was more suitable for predicting the optimal conditions in the optimization of BC production, the cost of developed culture medium was around 94% cost of HS medium preparation, molasses was the most effective factor in both experimental design methods, and initial pH adjustment had little impact on BC production. Then, the effect of inoculation conditions containing three factors of inoculation age, ethanol addition time, and agitation rate on the increase of BC production at three levels was investigated using the response surface methodology with the Box–Behnken design algorithm. Under the optimal conditions including inoculum age of 3 days, ethanol addition time of 10 days, and stirring speed of 100 rpm, the predicted and experimental results of BC production were 21.61 and 20.21 g/L, respectively. This is among the highest ever reported for BC production, which was achieved with a more cost‐effective culture medium containing molasses and CSL. [ABSTRACT FROM AUTHOR]

In the industrial application of bacterial cellulose (BC), the yield becomes a crucial factor because it drives the selling price of BC. A Box–Behnken experimental design with three components and three levels was employed to create seventeen samples. A response surface method was then used to optimize the BC yield from the most relevant parameters, including incubation temperature, medium shaking intensity, and nitrogen supply pH. Fourier transform infrared (FTIR) analysis proved that BC was pure. By analyzing BC morphology using scanning electron microscopy (SEM), rod-like microfibrils with an average diameter of 6.5 were revealed. X-ray diffraction (XRD) tested the crystalline size and crystallinity and found 4.7 nm and 69%, respectively. Thermal transition and stability were assessed using a differential scanning calorimeter (DSC) and a thermogravimetric analyzer (TGA). For the manufacture of BC composite hydrogel, a chemical test method was used to determine the solubility of BC. This study aimed to identify the ideal circumstances for using leftover sweet lime pulp for biomedical applications to produce reasonably priced and effective BC. At 28.87 °C, 125.91 rpm shaking frequency, and 5.65 pH, a sweet lime pulp waste medium produced the highest yield of BC, three times greater than the yield in a Hestrin–Schramm medium under static circumstances. [ABSTRACT FROM AUTHOR]

Immobilization of Acetobacter xylinum cells by trapping technique is considered one way to maintain cell viability and can be used repeatedly. The purpose of this study was to determine the physical characteristics of immobilized cells in different concentrations of Na-alginate and apply them to the manufacture of nata de coco, as well as to see the surface and pore shape of immobilized cells after fermentation. This study used a descriptive method with visual observation. This study used one factor, namely various concentrations of Na-alginate, namely 2%, 3%, 4%, and 5% w/v. The immobilized cells applied to the manufacture of nata de coco had only a Na-alginate concentration of 3% resulting in a nata fiber layer close to that of a control. Immobilized cells with a Na-alginate concentration of 2% have a cracked, slightly pore surface with a size of 60.37 μm, while a Na-alginate concentration of 5%, have a smooth surface, many pores, with a size of 10.55 μm. Thus, the concentration affects the characteristics of immobilized cells. Application of immobilized cells with a Na-alginate concentration of 3% produces nata de coco with a fairly thick and stable fiber layer characteristic (close to control).

Bacterial cellulose (BC) stands out as a prominent biopolymer of global importance, distinguished by its unique advantages over plant-derived cellulose. Strains such as Acetobacter xylinum, renowned for their proficient BC production, draw considerable attention in both commercial and biomedical areas. This research aimed to selectively isolate cellulose-producing bacteria with enhanced efficiency from a variety of fruit samples utilizing a cost-effective methodology. A total of 60 fruit samples were selected, and the assessment focused on 17 strains derived from rotten banana, red apple, green apple, and pineapple samples. The evaluation encompassed an examination of bacteriological traits and cellulose synthesis, with subsequent identification of strains achieved through DNA extraction and 16S rRNA PCR analysis. The experimental findings reveal cellulose-producing strains, including model A. xylinum (KCCM 40407) obtained from the Pharmacy lab of COMSATS University Islamabad Abbottabad Campus, Pakistan, designated as number 2, serving as a control. Notably, strains isolated from deteriorated fruits (samples 1, 4, 8, 11, 12, and 15) demonstrated the capacity to produce soluble cellulose. A. xylinum (model strain 2) was cultured under static conditions in HS media, demonstrating remarkable efficacy for cellulose sheet production. Subsequent characterization employing scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) unveiled a nano-fiber mat featuring multi-layered fibers. This eco-friendly approach has the potential for large-scale, high-quality cellulose production, applicable in biomedical and industrial fields. The research highlights an environmentally sustainable and economically viable method for cellulose production, presenting potential applicability across biomedical and industrial arenas on a significant scale.

ABSTRACTBacterial cellulose is a natural polymer, usually produced through synthetic (chemically defined) or natural media. However, the current methods of bacterial cellulose production are not ideal because of their low productivity and large number of byproducts. In order to improve the yield of bacterial cellulose, the influence of medium composition, culture time, culture temperature and culture pH on the production of bacterial cellulose by Acetobacter xylinum ATCC 23,767 was studied by single factor method. The optimal medium composition for Acetobacter xylinum can be analyzed by Thermal field emission scanning electron microscopy (TF-SEM) as glucose (20 g/L), yeast extract (5 g/L), peptone (5 g/L), citric acid (2 g/L). Using the logarithmic calculation method, we can determine that the optimal culture conditions are controlled by initial pH of the culture medium of 6 and constant static culture at 28°C for 9 days. Using TF-SEM, Fourier transform infrared (FT-IR) spectroscopy and water contact angle test, the best post-treatment solution can be selected as sodium hydroxide (1%). The results showed that the yield of bacterial cellulose could reach up to 8.5 g/L under the above conditions, and the obtained product exhibited a dense three-dimensional network structure.

Bacterial cellulose (BC) stands out as a prominent biopolymer of global importance, distinguished by its unique advantages over plant-derived cellulose. Strains such as Acetobacter xylinum, renowned for their proficient BC production, draw considerable attention in both commercial and biomedical areas. This research aimed to selectively isolate cellulose-producing bacteria with enhanced efficiency from a variety of fruit samples utilizing a cost-effective methodology. A total of 60 fruit samples were selected, and the assessment focused on 17 strains derived from rotten banana, red apple, green apple, and pineapple samples. The evaluation encompassed an examination of bacteriological traits and cellulose synthesis, with subsequent identification of strains achieved through DNA extraction and 16S rRNA PCR analysis. The experimental findings reveal cellulose-producing strains, including model A. xylinum (KCCM 40407) obtained from the Pharmacy lab of COMSATS University Islamabad Abbottabad Campus, Pakistan, designated as number 2, serving as a control. Notably, strains isolated from deteriorated fruits (samples 1, 4, 8, 11, 12, and 15) demonstrated the capacity to produce soluble cellulose. A. xylinum (model strain 2) was cultured under static conditions in HS media, demonstrating remarkable efficacy for cellulose sheet production. Subsequent characterization employing scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) unveiled a nano-fiber mat featuring -layered fibers. This eco-friendly approach has the potential for large-scale, high-quality cellulose production, applicable in biomedical and industrial fields. The research highlights an environmentally sustainable and economically viable method for cellulose production, presenting potential applicability across biomedical and industrial arenas on a significant scale. [ABSTRACT FROM AUTHOR]

This study investigates the synthesis and the antibacterial properties of bacterial cellulose (BC) incorporated zinc phosphate nanocomposite-mediated dragon fruit extract (BC-ZP-DF). The composite was prepared by a three-step process that involved bacterial cellulose (BC), zinc phosphate (ZP), and nanocomposite BC-ZP synthesis. BC was prepared by fermenting coconut water with the components of ammonium sulfate, acetic acid, and Acetobacter xylinum culture. Zinc phosphate was made through the green synthesis method by reacting zinc nitrate and diammonium hydrogen phosphate using a sensitizer agent from red dragon fruit peel extract (DF) with volume variations of 5, 10, 20, 30, 40, and 50 mL. The composite was prepared by immersing BC with zinc phosphate. Phase crystallinity, functional group, and morphology of the samples were characterized using XRD, FTIR, and SEM. It was found that the nanocomposite was constructed by the nano green of zinc phosphate in the form of a hopeite structure with antibacterial PO43- and OH functional groups. Morphological analysis using SEM revealed that the nanocomposites contained various small powder grains. Based on the FTIR spectrum, XRD pattern, and surface morphology of composite film, the incorporation of zinc phosphate in the BC framework was confirmed. The antibacterial activity tests of nanocomposite films using Staphylococcus aureus and Pseudomonas aeruginosa bacteria revealed that the nanocomposite was highly effective in inhibiting both bacteria, and the nanocomposite BC-ZP-DF10 film had the strongest inhibition. The results of the air filter test exhibited that the composition was efficient on all films with the highest percent of efficiency (%E) of 90.10%. [ABSTRACT FROM AUTHOR]

ABSTRACT One of the uses of coconut milk scheme is for the production of Nata De Skim Santan using Acetobacter xylinum bacteria and the addition of tofu whey substrate. This study aims to determine the effect of whey concentration on the characteristics of nata de coconut milk and the right optimum whey concentration on making nata de coconut milk. The independent variable used X1= Whey concentration with a lower limit of 0% (-1) and an upper limit of 50% (+1). The responses observed were yield (Y1), nata thickness (Y2), and moisture content (Y3). The results showed that the use of whey concentration had an influence on the characteristics of nata de coconut milk with Fvalue for the yield model, thickness model, moisture content model, and whey was 17.94, 24.83, 14.72, and 14.72. The optimum concentration of whey that is right for making nata de coconut milk was 49.07% with a desirability value of 0.89, the optimum yield was 29.71%, the optimum thickness was 1.13 cm, and the optimum moisture content was 89.7%. Keywords: Acetobacter xylinum, Coconut milk skim, Nata de coconut milk, Whey tofu

Extensive work on bacterial cellulose (BC) cultivation is crucial in optimizing BC performance and versatility in application. Herein, this study aims to investigate the lignin content in oil palm frond (OPF) juice medium that could affect the BC production by Acetobacter xylinum 0416 in static culture. The effects of lignin content were observed by the performances of BC production from the raw and pre-treated OPF juice medium fermentation with Hestrin-Schramm (HS) medium as a point of comparison. The TAPPI methods analysis outlined up to 3.719 g/L of total lignin content in raw OPF juice and FTIR analysis depicted the functional group of a typical lignin compound, thus confirming its presence as a component inhibitor. The raw OPF juice was further pre-treated using an alkaline precipitation method resulting in acid-insoluble lignin removal up to 75.47% of the total lignin content. The results revealed that the BC yield from the raw OPF juice fermentation was lower compared to the HS medium with dried BC content of 0.152 g/L and 2.52 g/L, respectively. The BC cultivation using the pre-treated OPF juice medium was improved as the BC yield significantly increased to 1.91 g/L. Therefore, a proper pre-treatment strategy on OPF juice medium for lignin content removal could improve the medium capability in BC cultivation for higher-scale production. [ABSTRACT FROM AUTHOR]

Polymers have been used in various industries over the past few decades due to their tremendous applications. Among these, polyhydroxyalkanoates and poly(lactic acid) are easily biodegradable biopolymers derived from bacteria, including recombinant Escherichia coli, Alcaligenes eutrophus, Alcaligenes latus, Azotobacter vinelandii, methylotrophs and Pseudomonas. Conventional petroleum‐derived polymers have become potentially harmful to the environment due to their complex degradation process. The nonbiodegradability of synthetic polymers has become a global issue of concern. There is an urgent need for a substitute to tackle the increasing environmental stress. Microorganisms are small factories for producing different types of polymers during their growth cycle. Various features like biodegradability, biocompatibility, nontoxicity and wide substrate spectrum make such microbial polymers highly reliable. Biopolymers such as alginate, cellulose, cyanophycin, levan, polyhydroxyalkanoates, xanthan, poly(lactic acid) and poly(γ‐glutamic acid) can be obtained from different microorganisms like Aureobasdium pullulans, Acetobacter xylinum, Bacillus thermoamylovorans and Cupriavidusnecator. These are extensively used in various fields like food, medicine, wastewater treatment, biofuel production, packaging and cosmetics. Despite being advantageous in several ways, the biopolymer market still faces several hurdles. This review mainly emphasizes the different types of biopolymers, production by microorganisms and various applications of these biopolymers in different fields. The main drawback limiting the development of these polymers is the high production cost and low efficiency of the microbial strains. Genetic recombination is an efficient technique to enhance the microbial yield and to expand the biopolymer market size. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Durian seeds are a waste product from durian fruit. Durian seeds are often used by people as the main ingredient in making bread and cakes. However, the use of durian seeds as the main ingredient in making nata has never been done. Nata is extracellular cellulose obtained from the activity of the bacteria Acetobacter xylinum. The nata that is often found is nata de coco made from coconut water as the main ingredient. This research aims to look at the formation of nata de durio from durian seeds. The results showed that different dry weights of durian seeds did not affect the thickness of the Nata De Durio formed. The thickness of Nata De Durio on days 7 and 14 was highest at a dry weight of 250 grams of durian seeds with an average of 0.4 and 0.5 cm and the lowest was at a dry weight of 100 grams of durian seeds with an average of 0. 3 and 04 cm. Conclusion: The difference in dry weight of durian seeds does not affect the thickness of Nata De Durio. However, the dry weight of 250 gram durian seeds has a better Nata De Durio thickness compared to the dry weight of 100 grams and 200 grams of durian seeds. [ABSTRACT FROM AUTHOR]

Nata de coco produced via coconut water fermentation using Acetobacter xylinum was directly applied to remove metal cations in aqueous solutions without any further chemical modification. Bacterial cellulose, contributing just 0.8 wt % to nata de coco, were randomly distributed and interconnected, yielding a three‐dimensional framework with high crystallinity and porosity. Due to these characteristics and the abundant presence of electron‐rich hydroxyl groups, unmodified bacterial cellulose in nata de coco exhibited a strong affinity to metal cations in water. The adsorption efficiency of nata de coco can be significantly improved to ∼30 and ∼45 mg g−1 for Pb2+ and Fe3+, respectively, by decreasing its size by grinding to decrease its size. Notably, nata de coco can adsorb multiple cations and the uptakes were almost similar for a 100‐fold scaled‐up adsorption volume. [ABSTRACT FROM AUTHOR]

Porous hydroxyapatite (HA) was prepared by a chemical reaction between eggshell and phosphoric acid mixed with a foaming agent. Hydroxyapatite was composited with collagen prepared from a fermentation process of Acetobacter xylinum with eggshell membranes, extraction process of Oreochromis niloticus fish skin, and commercial‐grade collagen. Results of physical‐mechanical‐thermal properties of the bio composite materials yielded them as potential candidates for bone tissue engineering, drug delivery through the body, as well as tissue regeneration. The porous hydroxyapatite added foaming agent namely 64HA‐1NaHCO3‐500 and 64HA‐1NaHCO3‐600 having pore size and pore volume suitable for good adhering of collagen fiber types prepared from the fermentation process of Acetobacter xylinum of eggshell membrane and freeze‐drying process of Oreochromis niloticus. Because after reinforcing with collagen gave the highest compressive strength and three‐point bending strength values higher than HA samples without collagen three to five magnitudes. Furthermore, both bio composite samples served as positive thermal shock absorbers with significantly strong scanning electron microscope adhesion microstructures of collagen fibers within the porous HA matrices. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) microstructured biomaterials are favorable in tissue engineering due to their superior guidance to cellular activities. Herein, we developed a 3D microstructured bacterial cellulose (BC) with arranged fibers by controlling Acetobacter xylinum through an electric field (EF) application. The real-time video analysis showed that EF directed the migration of A. xylinum and increased its migration speed with the increased EF. The bacteria quickly changed direction with high motility in response to the switch on/off of the EF. In the long-term electrical stimulation (ES), the growth of A. xylinum was influenced. Likewise, bacterial cells were oriented along the direction of EF while bacteria simultaneously produced nanocellulose, resulting in 3D networks with aligned fibers. The prepared 5 mA-BC hydrogels presented the ordered 3D microstructure with higher fiber alignment, diameter and flexibility than that of NO EF-BC hydrogels. The in vitro biological evaluation demonstrated that the 5 mA-BC hydrogels were biocompatible whereon NIH3T3 cells proliferated along the direction of fiber alignment. These findings demonstrate that ES provides a promising strategy for the natural fabrication of aligned 3D microstructured BC to guide cellular activities for tissue regeneration. [ABSTRACT FROM AUTHOR]

Acetobacter spp. that are commonly found on fruits, can perform oxidation processes, resulting in acetic acid production in vinegar. Besides that, Acetobacter spp. able to produce bacterial cellulose (BC), which is an essential by-product. This present study was carried out to isolate Acetobacter spp. from selected local fruits. Species verification of the bacterial isolates was performed using molecular and bioinformatic approaches. A total of six local fruits (starfruit, jackfruit, watermelon, pineapple, honeydew & banana) were subjected to seven days of fermentation in a brown sugar solution. Acetobacter spp. were isolated from the fermented medium using bromocresol green ethanol agar as the selective medium. Thirteen bacterial isolates were obtained and subjected to molecular works, including DNA extraction and PCR amplification using universal primers, targeting the 16S rRNA genes. PCRamplified products were selected for single-pass sequencing. BLASTn analysis of the sequencing results showed three isolates (23.1%) belonging to Acetobacter tropicalis and one isolate (7.7%) representing Gluconobacter oxydans might have potential in BC production. However, the remaining nine isolates (69.2%) hit the Lactobacillus genus. Morphological observation using FESEM showed that the BC produced by all the positive bacterial isolates is similar to dried nata de coco and BC produced by Acetobacter xylinum. In addition, four similar regions of -OH stretch (3400 - 3300 cm-1), -CH stretch (2970 to 2800 cm-1), -OH bending (1620 cm-1), and -COC stretch (1100 to 1073 cm-1) are identified in the BC samples. In the future, the isolated Acetobacter and Gluconobacter strains could be further utilized for large-scale BC production in a suitable fermentation medium. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) is a potential eco-friendly biopolymer. BC has higher crystallinity and purity compared to plant cellulose. Scientific studies on the production of BC from lactic acid bacteria (LAB) are minimal compared to other common bacteria such as Acetobacter xylinum. LAB was screened and isolated from different tissues of Mimosa pudica (medicinal plant) using MRS broth and agar as the selective medium. LAB isolates were subjected to 16S rRNA gene sequencing of all the bacterial isolates. BC was produced from all LAB isolates by incubating at 30 °C for 14 days in herbal tea medium (Strobilanthes crispus) and HS medium (control) with 130 rpm agitation. BC produced by two selected bacterial isolates was characterized using FESEM, FTIR, XRD, and TGA. Molecular analysis of the 16S rRNA gene of all the potential LAB isolates shows 99.86 - 100% identity to 16S rRNA sequences of other Lactobacillus plantarum strains. Two selected L. plantarum strains (LBM001 & LBM004) produce BC in sphere-like particles with a 1.4 to 2.2 µm diameter range of microfiber. FTIR analysis shows that BC produced by LBM001 and LBM004 have four similar cellulose regions identified in cellulose from other sources, which are O-H stretch (3400-330 cm-1), C-H stretch (2970-2800 cm-1), O-H bending (1620cm-1) and C-O-C stretch (1100-1073 cm-1). XRD analysis shows BC produced by the L. plantarum strains consists of two different XRD peaks at the 2? angle of 21.53° and 21.85° instead of a single peak (22.76°) identified in the BC produced by A. xylinum and plant cellulose. A similar TG and DTG curved pattern was detected in the BC produced by the L. plantarum strains with the BC produced by A. xylinum and plant cellulose. The LAB isolates from M. pudica have potential in BC production based on the multiple characterization studies. [ABSTRACT FROM AUTHOR]

Nata adalah selulosa dari bakteri yang diperoleh dari fermentasi Acetobacter xylinum. Nata sering ditemukan dalam makanan penutup sebagai suplemen kesehatan karena kandungan seratnya yang tinggi. Nata tidak hanya dihasilkan dari air kelapa yang dikenal dengan nata-de-coco, tetapi juga dapat dihasilkan dari sumber lain seperti air limbah cucian beras yang disebut dengan nata-de-leri. Penelitian ini bertujuan untuk mengoptimalkan parameter dalam fermentasi nata-de-leri dengan metode statistik dalam rangka meningkatkan produksi nata. Hal yang dilakukan yaitu, pertama melakukan desain untuk menyeleksi parameter yang berpegaruh menggunakan respon yield menggunakan Design Placket-Burman. Ada delapan factor yang kaji untuk kemudian didapatkan faktor yang paling berpengaduh agar mudah dalam optimasi nantinya. Hal kedua yang dilakukan adalah optimasi empat parameter yang paling berpengaruh menggunakan Central Composite Design (CCD) dengan respon hasil yield. Hasil dari penelitian menunjukkan bahwa konsentrasi gula, konsentrasi CO(NH2)2, konsentrasi starter inokulum dan waktu fermentasi merupakan faktor yang penting dalam produksi nata de leri. Hasil parameter untuk menghasilkan yield optimal dalam produksi nata de leri ketika menggunakan 500 ml substrat limbah cucian beras adalah menggunakan gula sebanyak 17,5 g; CO(NH2)2 sebanyak 12 g; volume starter sebanyak 60 mL dan waktu fermentasi selama 12 hari. Dari parameter tersebut menghasilkan rendemen sebesar 97,20%. Dari optimasi dalam penelitian ini menghasilkan peningkatan produksi nata de leri sebesar 20% dari kondisi awal sebelum dioptimasi.

Nata de coco adalah makanan fungsional yang mengandung fiber. Nata de coco merupakan produk fermentasi bakteri Acetobacter xylinum yang ditumbuhkan pada media cair seperti air kelapa. Selain dari air kelapa, mikroba juga memerlukan nutrisi tambahan yaitu dari carbon dan nitroge untuk pertumbuhannya yang dilakukan dalam proses fermentasi. Selama ini penambahan sumber nitrogen dilakukan dengan menggunakan urea dan ZA yang juga digunakan untuk pupuk pertanian, sehingga sebagian orang meragukan keamanannya. Dalam penelitian ini mengkaji potensi dimetil amino phosphate (DAP) sebagai sumber nitrogen dalam fermentasi nata de coco. Nata dibuat dengan menggunakan 500 ml air kelapa yang telah disterilkan ditambah 17,5 g gula, 20 ml asam cuka, 60 ml starter Acetobacter xylinum serta ditambah variasi DAP (0, 0.05, 0.25, 0.5, 2.5 dan 3.4 g). Sedangkan sebagai kontrol yaitu nata dengan menggunakan sumber nitrogen urea dan ZA masing – masing sebanyak 3 g. Fermentasi dilakukan selama 10 hari dan setelahnya dilakukan analisis fisik (yield dan tebal nata), analisis kimia (kadar air dan kadar serat) dan uji organoletis (rasa dan tekstur). Hasil penelitian menunjukkan bahwa hanya pada penambahan DAP yang rendah (0.05 g) memberikan karakteristik fisik yang significant sama (p>0.05) terhadap control. Sedangkan jumlah kadar air significant sama dengan control dan sample yang lain. Kadar serat menunjukkan hasil yang lebih besar dari pada control (3,9 %) dan semua sample nata menggunakan DAP rasa disukai oleh responden dengan tekstur kenyal seperti control. Dari penelitian ini dapat disimpulkan bahwa DAP dapat menggantikan urea dan ZA sebagai sumber nitrogen dalam pembuatan nata de coco.

The fashion industry is well known for its highly polluting production processes. Researchers around the world still are looking for alternative sustainable raw materials. Bacterial cellulose is one such biomaterial, sustainable, and environmental friendly and has a lot of potential in the fashion industry. In this review, the application possibility of bacterial cellulose in the fashion industry is taken as a major concern. The review mainly focuses on the previous researches in the area to evaluate the various production methods and raw materials used in bacterial cellulose manufacturing using Acetobacter xylinum. In addition to that, the review also consolidates the carbon source materials utilized for the bacterial cellulose production by various researchers. In specific, the fashion application-related research works were analyzed. It was found that production cost and lower yield are the major issues in the bulk production of bacterial cellulose and hence, the search continues for cost-effective raw materials with better cellulose yield. The tea medium is so far successfully used for bacterial cellulose fabric production. However, the inherent properties like higher water-holding capacity, loss of flexibility, and structural disorientation on drying are addressed as major issues concerning the fashion industry.

Nata adalah lapisan polisakarida ekstraseluler (selulosa) yang dibentuk oleh mikroba pembentuk kapsul. Nata termasuk produk fermentasi yang mengandung bakteri Acetobacter xylinum, jika ditumbuhkan di media cair yang mengandung gula misalnya ekstrak kulit nanas, bakteri ini menghasilkan lapisan putih nata yang terapung-apung di permukaan media tersebut. Tujuan dari penelitian ini adalah untuk menyeleksi variabel yang paling berpengaruh pada proses pembuatan nata de pina menggunakan Placket-Burman Screening Design Method, variabel yang akan dikaji adalah rasio perbandingan air dan kulit nanas, sumber karbon (gula), sumber nitrogen (urea), sumber phospat (K2HPO4), sumber vitamin (vitamin B syrup), pH, lama fermentasi, dan jumlah starter. Dari hasil Placket-Burman Screening Design diperoleh bahwa jumlah sumber karbon (C), jumlah sumber phospat (P), dan jumlah starter (JS) merupakan variabel yang sangat berpengaruh terhadap hasil yield fermentasi.

The competitiveness of bacterial cellulose (BC) production with plant cellulose can be achieved by production on cost-effective media. It was found that the bacterial cell number ratio of BC to culture medium increases over time so that from the fourth day, the entrapped cell number in the cellulose network exceeds the suspended cells. Optimization based on 23-full factorial showed that inoculum development at 50 rpm and the main culture process under static conditions significantly increases BC production. A cost-effective culture medium containing molasses (ML) and corn steep liquor (CSL) was developed based on the same C/N ratio to HS medium, with 7.24 g/l cellulose at C/N ratio 12.6 is competitive with maximum production 8.7 g/L in HS medium. The BC production cost was reduced about 94% using the proposed cheap and locally available medium containing ML and CSL, while BC mechanical properties increased by about 50%. [ABSTRACT FROM AUTHOR]

Cellulose produced by fermentation of acetic acid bacteria has high tensile strength. Meanwhile, cellulose derived from wood, which is abundant in nature, has a limit in strength. In this work, delignified wood veneer was immersed in Acetobacter xylinum culture medium to self-assemble bacterial cellulose into wood pores. Then the process was continued with a heating press. It makes the material denser and causes hydrogen bonds to form between the cellulose fibers. This study observed the densified hybrid veneer for the period of bacterial fermentation and impregnation of resin stabilization in tensile strength and dynamic mechanical analysis (DMA). The densified hybrid veneer of bacterial cellulose with resin impregnation had the maximum tensile strength after 7 days of fermentation. The DMA test showed that a densified hybrid veneer of bacterial cellulose stabilized with resin has a good ability to store cyclic energy and a damping factor that increases with temperature. [ABSTRACT FROM AUTHOR]

The development of alternative food packaging films using bio-based residues is in great demand for replacing petroleum-based packaging materials. However, large-scale application is severely limited by costly production and poor performance. This study investigates the ex-situ modification of bacterial cellulose (BC) produced by Acetobacter xylinum in oil palm fronds juice to obtain BC-Chitosan (BCC) films. FTIR revealed the structure of amide I and II bands, confirming the presence of chitosan in BCC films. The FE-SEM images of BCC films showed the formation of a thick chitosan layer with increasing chitosan incorporated into the BC surface structure. The coated chitosan layer observed improved mechanical properties in BCC films due to the disappearance of empty pores between BC fibers. Increments in chitosan concentration slightly decreased the thermal behavior of BCC. The antimicrobial effects of BCC films were effective against Gram-positive bacteria (Staphylococcus aureus) when the concentration of chitosan incorporated was above 0.6 %w/v. This study reveals the potential of extending the application of BC derived from oil palm frond juice (OPFJ) for developing food packaging materials. [ABSTRACT FROM AUTHOR]

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.

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Renewable fermentation feedstock from a freshly cut oil palm frond (OPF) is a promising medium for bacterial cellulose (BC) production. Herein, this study assessed its suitability as a solitary medium for the production of BC using Acetobacter xylinum 0416 in a static culture. The proximate composition and components analysis revealed up to 36.2 g/L of fermentable sugars and vital nutrients were available in OPF juice. Meanwhile, the effect of OPF juice concentration and initial pH arrangement shows that the maximum yield of BC (2.33 g/L) was obtained using 60% v/v of OPF juice concentration at initial pH 3.5 and incubated at 30℃ for 14 days. Besides, pure OPF juice showed a minimum in BC production due to the presence of inhibitory component suspected to be the lignin content. The kinetic study was elucidated for BC produced from OPF juice and compared with coconut water medium. The FT-IR and XRD spectra, and FE-SEM micrograph analysis for the BC showed the typical peaks represent in cellulose with a crystallinity index of 82.4% and threadlike microfibrils structure ranging from 35.6.5 nm to 77.5 nm. Thus, OPF juice is a solely sufficient medium that offers a positive alternative to BC production. [ABSTRACT FROM AUTHOR]

This work aimed at conversion of worthless indurtial wastes to valuable product. Herein, bioactive composites based on bacterial cellulose (BC) and eggshell or eggshell-derived hydroxyapatite (HAp) were prepared by a green method using Gluconacetobacter xylinum bacteria. The effect of addition of eggshell (BC/Eg) and eggshell-derived HAp (BC/HAp-Eg) on the bacterial cellulose yield, biodegradation and biocompatibility was studied. For comparison, HAp derived from chemical precursors was synthesized (BC/HAp-ch). The resultant composites were characterized by XRD, FTIR, and SEM/EDX. Furthermore, the biodegradation and bioactivity were assessed in SBF, and the cell viability was studied against oral normal cells. The results showed that the productivity of BC applied HAp-derived eggshell (1.83 g/L) was higher than that of using (1.37 g/L). Interestingly, the eggshell was converted to Ca3(PO4)2 during incubation in the bacterial culture medium, while Ca3(PO4)2 was formed as a secondary phase when using either eggshell-derived HAp or chemically-derived. The in vitro bioactivity test in SBF showed that all composites were induced the formation of a bone-like apatite layer on their surface with Ca/P ratio, 1.49, 1.35, and 1.41 for BC/Eg, BC/HAp-ch, and BC/HAp-Eg, respectively, near to the ratio in the natural HAp. Finally, the in vitro cell viability test was confirmed good biocompatibility against the composites. However, at high sample concentration (250 µg/mL), BC/HA-Eg showed the higher cell viability (95.2%) than that of BC/Eg (80.5%) and BC/HA-ch (86.2%). In conclusion, eggshell waste could be used directly with bacterial cellulose to produce bioactive composites without the need to convert it to HAp which reduced the cost of production and thus has a higher economic return. Obiviously, eggshell waste can act as calcium, organic matter source, pH preservation, nuterilizing agent along with potential instead of costly buffering agent in the BC culture medium and further for increased the BC production. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) producing bacterial strains were isolated from bio-extract (BE). Nine isolates that can produce BC in Hestrin–Schramm medium (HS medium) were identified. The BC production of these isolates was then investigated using agricultural waste as a raw material. The agricultural waste (banana, papaya, dragon fruit, and mango peels) was used as a carbon source for BC production. After incubation, the highest dry weight of BC reached 0.93±0.27 g/L, and 4.07±0.27 g/L was obtained from isolate BE073 in a medium containing mango and dragon fruit peels because the raw materials state is appropriate for bacterial growth. In a medium with papaya peel, the highest dry weight of BC was obtained from isolate BE052 at about 1.08±0.05 g/L. None of the strains was able to grow with the banana medium. However, all the isolate strains could grow and produce BC in the HS medium. The maximum dry weights of BC of 4.31±0.45 g/L, 4.23±0.13 g/L, and 4.21±0.25 g/L were obtained from isolates BE123, BE052, and BE073, respectively, and Acetobacter xylinum produced BC at 2.39±0.11 g/L. The structure and physical properties of BC produced from bacterial isolates using agricultural waste were characterized. It was similar to BC produced from HS medium and production from the reference strain A. xylinum. This study demonstrates the ability for BC production of bacterial strains isolated from bio-extract. It is also demonstrated that agricultural waste is a suitable and alternative carbon source for raw material in BC production. [ABSTRACT FROM AUTHOR]

The liquid waste from the production of fruit preserves was used as an alternative carbon source to replace sugar in the traditional Hestrin-Schramm (HS) and coconut water media (CM) and reduce the cost of bacterial cellulose (BC) production. The sugar components of liquid wastes from preserved tamarind (LWT) and preserved mango (LWM) were characterized, and the total sugars were between 237.50 g/L and 231.90 g/L. The effects of the nutrients in the media with LWT and LWM on the production of BC by Acetobacter xylinum were determined. The result showed that A. xylinum could grow and produce BC in the media with liquid waste. The highest concentration of BC, 6.60±0.04 g/L, was obtained from the medium containing 25% (v/v) LWM. In a medium containing LWT, A. xylinum produced a maximum BC of 5.50±0.30 g/L when 12.5% (v/v) LWM was added. However, when the structure and physical properties of the BC from the liquid waste were characterized, it was similar to BC from the HS medium and CM medium without liquid waste. [ABSTRACT FROM AUTHOR]