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This study presents the ex situ development and characterization of bacterial cellulose (BC) membranes loaded with bioactive Sage and Neem extracts for enhanced antimicrobial applications. Utilizing discarded fruit waste as a cost-effective carbon source, BC production was optimized, yielding membranes with improved properties. Neem and Sage extracts, obtained via Soxhlet extraction, exhibited significant antibacterial activity against Escherichia coli and Staphylococcus aureus, with minimum inhibitory concentrations of 3.125 mg/mL and 25 mg/mL, respectively, for Neem extract, and 25 mg/mL and 50 mg/mL for Sage extract. These extracts (20 wt%) were successfully incorporated into BC membranes ex situ, resulting in BC-Neem (BC-N) and BC-Sage (BC-S) composites. Fourier-transform infrared spectroscopy (FTIR) confirmed the chemical interactions between the extracts and the BC matrix, revealing the introduction of new functional groups and enhancing the composite properties. Scanning electron microscopy (SEM) illustrated changes in morphology, indicating deeper penetration and attachment of the extracts within the BC structure. Quantitative analysis of water holding capacity demonstrated that BC-N and BC-S absorbed about 90 times water of their dry weight. Antibacterial assays through the colony-forming unit method showed that BC-N significantly inhibited S. aureus growth by 78 % and E. coli by 51 %, while BC-S exhibited a 48 % reduction against S. aureus. Agar disc-diffusion assay showed the formation of inhibition zones of 1.2 cm and 0.1 cm by BC-N against S. aureus and E. coli, respectively, in contrast to 0.2 cm and no inhibition by BC-S composite. These results highlight the potential of bioactive plant extract-loaded BC membranes as effective antimicrobial agents, offering a sustainable alternative to conventional materials in medical and food packaging applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study was aimed to develop low-cost bacterial cellulose (BC)-based antibacterial composite with pomegranate (Punica granatum L.) peel extract (PGPE) for potential biomedical applications. BC was cost-effectively produced by utilizing food wastes, and PGPE was ex situ impregnated into its hydrogel. Field-emission scanning electron microscopic (FE-SEM) observation showed a nanofibrous and microporous morphology of pristine BC and confirmed the development of BC-PGPE composite. Fourier transform infrared (FTIR) spectroscopy indicated the chemical interaction of PGPE with BC nanofibers. BC-PGPE composite held 97 % water of its dry weight and retained it for more than 48 h. The BC-PGPE composite exhibited better reswelling capabilities than pristine BC after three consecutive re-wetting cycles. The antibacterial activity of the BC-PGPE composite was determined via minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), disc diffusion, and plate count methods. The PGPE extract showed good antimicrobial activity against Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative), both in the form of extract and composite with BC, with relatively better activity against the former. The BC-PGPE composite produced a 17 mm zone of inhibition against S. aureus, while no inhibition zone was formed against E. coli. Furthermore, BC-PGPE composite caused a 100 % and 50 % reduction in the growth of S. aureus and E. coli, respectively. The findings of this study indicate that BC-PGPE composite could be a promising antibacterial wound dressing material., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Bacterial cellulose (BC), an extracellular polysaccharide, is a versatile biopolymer due to its intrinsic physicochemical properties, broad-spectrum applications, and remarkable achievements in different fields, especially in the biomedical field. Presently, the focus of BC-related research is on the development of scaffolds containing other materials for in-vitro and in-vivo biomedical applications. To this end, prime research objectives concern the biocompatibility of BC and the development of three-dimensional (3D) BC-based scaffolds. This review summarizes the techniques used to develop 3D BC scaffolds and discusses their potential merits and limitations. In addition, we discuss the various biomedical applications of BC-based scaffolds for which the 3D BC matrix confers desired structural and conformational features. Overall, this review provides comprehensive coverage of the idea, requirements, synthetic strategies, and current and prospective applications of 3D BC scaffolds, and thus, should be useful for researchers working with polysaccharides, biopolymers, or composite materials., (Copyright © 2022. Published by Elsevier B.V.)

This study reports the synthesis of bacterial cellulose (BC) hydrogel sheets and their utilization as a support for silver‑nickel oxide nanocomposites (Ag/NiO). A two-step facile hydrothermal method was employed for the preparation of Ag/NiO, followed by impregnation into BC hydrogel sheets. A 20% Ag/NiO composition was revealed by dry weight analysis. The stability of nanocomposites-Hydrogel was confirmed by Ag + and Ni 2+ ion release study. The catalytic activity of the BC-Ag/NiO was evaluated against chemical reduction of congo red, methyl orange and methylene blue. The reduction reaction followed pseudo first order kinetics and k app values of 0.1147 min -1 , 0.1323 min -1 and 0.12989 min -1 were obtained for CR, MO, and MB dyes, respectively. The BC-Ag/NiO catalyst could be easily recovered and re-used in another reaction without centrifugation. The synthesized nanocomposites hydrogel was also tested for its antibacterial activity against Gram-negative bacteria, Escherichia coli (E.coli) and Gram-positive bacteria, Staphylococcus aureus (S.aureus)., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Bacterial cellulose (BC) has received immense interest in medical, pharmaceutical, and other related fields owing to its intrinsic physical, mechanical, and biological features. Its structural features offer an ideal environment for developing composites, thereby further extending its areas of applications. BC was initially used in wound dressing, artificial blood vessels, organ development, and tissue regeneration; however, the recent focus has switched to 3D printing techniques. BC can serve as suitable material for treating different cancers due to unique liquid absorbing and drug loading properties. BC-based scaffolds have been synthesized and tested for in vitro culturing of cancer cells to simulate tumor microenvironments. These scaffolds support normal growth of cancer cells, particularly breast and ovarian cancer cells, showing significant adhesion, proliferation, ingrowth, and differentiation. This review describes the different approaches of manipulating BC for use in medicine, with particular focus on the applications of BC composites in cancer treatment. A detailed discussion about various formulations of BC in multiple cancer therapeutics is summarized., Competing Interests: Declaration of competing interest All authors have no personal or financial conflicts of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Bacterial cellulose (BC), representing the highly purified form of cellulose, possesses better nanofibrous morphology and superior mechanical properties than plant cellulose (PC). However, the regeneration process, which produces intermediate structures, significantly alters the original properties of native cellulose and result in varied structural and physico-mechanical features. Therefore, it is important to estimate the degree of variations in the structures and properties of both PC and BC during their regeneration. Herein, we conducted a detailed comparative study by dissolving BC and PC in N-methylmorpholine N-oxide (NMMO) and synthesizing their regenerated gels, namely regenerated bacterial cellulose (RBC) and regenerated plant cellulose (RPC), respectively. The structural features of BC, PC, RBC, and RPC were comparatively evaluated via field-emission scanning electron microscopy, X-ray diffraction, porosity analyses, as well as analyzed their mechanical, thermal, and liquid-holding capabilities. The results showed inferior mechanical, thermal, and crystalline features of RBC and RPC to their respective counterparts. However, RBC showed better porosity, water absorption capability, and water retention time than RPC. The overall mechanical, thermal, and physiological features of RBC were better than those of RPC. These findings may facilitate the use of RBC in composite synthesis for various applications., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Bacterial cellulose (BC) has emerged as a biomaterial for diverse biomedical applications owing to its unique structural, physico-chemical, mechanical, and biological features. Its porous geometry and three-dimensional fibrous structure allow the impregnation of various materials into its matrix. The current study was aimed to fabricate 3D scaffolds of bacterial cellulose and chitosan (BC-Chi) through a one-step ex situ solution impregnation strategy and analyze the scaffold interaction with the ovarian cancer cell lines (A2780). Field emission scanning electron microscopy (FE-SEM) showed successful impregnation of chitosan into the BC matrix. Phase-contrast and confocal microscopy analyses revealed that human ovarian cancer cell lines (A2780) were adhered not only to the surface but deeply infiltrated into the matrix of BC-Chi scaffold. WST-1 assay, histology analysis, and cytoskeleton and nuclear staining showed high viability, proliferation, and infiltration of A2780 cell lines into the scaffold. The RT-PCR analysis revealed a decreased mRNA level of Notch receptors, indicating a strong cell-scaffold interaction. The improved biocompatibility, non-toxicity, and 3D structure of fabricated BC-Chi scaffold justify its potential applications diagnosis of ovarian cancer in vivo., (Copyright © 2019 Elsevier B.V. All rights reserved.)

This study reports the fabrication of porogen-induced, surface-modified, 3-dimensionally microporous regenerated bacterial cellulose (rBC)/gelatin (3DMP rBC/G) scaffolds for skin regeneration applications. Round shaped gelatin microspheres (GMS), fabricated using a water-in-oil emulsion (WOE) method, were utilized as the porogen. The dissolution of GMS from the solution casted BC scaffolds led to surface-modified microporous rBC. The scaffolds were characterized using field emission scanning electron microscopy (FE-SEM) and elemental analysis. FE-SEM analysis confirmed the regular microporosity of the 3DMP rBC/G scaffolds, while elemental analysis confirmed the successful surface modification of cellulose with gelatin. In vitro tests showed good adhesion and proliferation of human keratinocytes (HaCaT) on the 3DMP rBC/G scaffolds during 7 days of incubation. Confocal microscopy showed penetration of HaCaT cells into the scaffolds, up to 300 μm in depth. In vivo wound healing and skin regeneration experiments, in experimental mice, showed complete skin regeneration within 2 weeks. The wound closure efficacy of the 3DMP rBC/G scaffolds was much higher (93%) than that of the control (47%) and pure BC-treated (63%) wounds. These results indicated that our 3DMP rBC/G scaffolds represent future candidate materials for skin regeneration applications., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A new route to fabricate cotton cloth (CC) as easily removable substrate for the synthesis of copper nanoparticles on its surface and its utilization in a toxic dye reduction is reported herein. A 1 wt% chitosan (Chi) aqueous solution was prepared and coated onto CC surface to prepare the ions affinity Chi-CC material. The Chi-CC was then kept in copper sulphate solution with three different concentrations (0.05 M, 0.1 M and 0.2 M) to interact with Cu 2+ ions through -NH and -OH functional groups of the Chi chain. After sufficient time of the Cu 2+ uptake, the Chi-CC was treated with 0.1 M NaBH 4 solution which turned its color indicating well organization of the adsorbed ions into Cu-nanoparticles. The bare CC, Chi-CC and Cu/Chi-CC were spectroscopically examined via scanning electron microscopy, X-ray diffractometry, energy dispersive X-ray spectroscopy and thermo-gravimetric analysis. Afterward, Cu/Chi-CC was used in the Congo red (CR) dye reduction by NaBH 4 as catalyst. The performance of the amount of the catalyst and its usage in a series of similar dye reduction was evaluated., (Copyright © 2018 Elsevier B.V. All rights reserved.)

This study reports the fabrication of highly conducting and biocompatible bacterial cellulose (BC)-gold nanoparticles (AuNPs)-poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) (BC-AuNPs-PEDOT:PSS) composites for biology-device interface applications. The composites were fabricated using ex situ incorporation of AuNPs and PEDOT:PSS into the BC matrix. Structural characterization, using scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and x-ray diffraction (XRD) analysis, confirmed the uniform nature of the synthesized BC-AuNPs and BC-AuNPs-PEDOT:PSS composites. Four-point probe analysis indicated that the BC-AuNPs and BC-AuNPs-PEDOT:PSS films had high electrical conductivity. The composites were also tested for biocompatibility with animal osteoblasts (MC3T3-E1). The composite films supported adhesion, growth, and proliferation of MC3T3-E1 cells, indicating that they are biocompatible and non-cytotoxic. AuNPs and PEDOT:PSS, imparted a voltage response, while BC imparted biocompatibility and bio-adhesion to the nanocomposites. Therefore, our BC-AuNPs-PEDOT:PSS composites are candidate materials for biology-device interfaces to produce implantable devices in regenerative medicine., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Pure chitosan and its zinc oxide composite coatings were applied on microfibriller cellulose mat (MCM) to prepare chitosan coated microfibriller cellulose (Chi-MCM) and zinc oxide/chitosan coated microfibriller cellulose (ZnO/Chi-MCM), respectively. X-ray diffraction (XRD), and scanning electron microscopy (SEM), were used to characterize the samples in this study. SEM images showed that dense chitosan solutions (3 and 5wt%) made a thick layer over MCM while diluted solution (1wt%) resulted in wrapping of the chitosan over the individual microfibers and avoided the thick layer formation. Removal of an azo dye methyl orange (MO) from aqueous solution using adsorption and combined adsorption with photodegradation activity of the Chi-MCM and ZnO/Chi-MCM were evaluated, respectively. Compared in the absence of UV light, ZnO/Chi-MCM showed faster and higher degree of dye removal by photocatalytic dissociation and adsorption under ultraviolet irradiation. Various parameters including pH of MO solution and its initial concentration were tested for the removal of MO dye. ZnO/Chi-MCM showed maximum adsorption capacity of 42.8mg/g. Antibacterial activities were also evaluated where ZnO/Chi-MCM displayed a remarkable performance inhibiting the Escherichia coli growth., (Copyright © 2015 Elsevier B.V. All rights reserved.)