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Cellulosic materials are attracting increasing research interest because of their abundance, biocompatibility, and biodegradability, making them suitable in multiple industrial and medical applications. Functionalization of cellulose is usually required to improve or expand its properties to meet the requirements of different applications. Cellulose-binding domains (CBDs) found in various proteins have been shown to be powerful tools in the functionalization of cellulose materials. In this review, we firstly introduce the structural characteristics of commonly used CBDs belonging to carbohydrate-binding module families 1, 2 and 3. Then, we summarize four main kinds of methodologies for employing CBDs to modify cellulosic materials (i.e., CBD only, genetic fusion, non-covalent linkage and covalent linkage). Via different approaches, CBDs have been used to improve the material properties of cellulose, immobilize enzymes for biocatalysis, and design various detection tools. To achieve industrial applications, researches for lowering the production cost of CBDs, improving their performance (e.g., stability), and expanding their application scenarios are still in need. [ABSTRACT FROM AUTHOR]

Fabricating three-dimensional (3D) scaffolds is attractive due to various advantages for tissue engineering, such as cell migration, proliferation, and adhesion. Since cell growth depends on transmitting nutrients and cell residues, naturally vascularized scaffolds are superior for tissue engineering. Vascular passages help the inflow and outflow of liquids, nutrients, and waste disposal from the scaffold and cell growth. Porous scaffolds can be prepared by plant tissue decellularization which allows for the cultivation of various cell lines depending on the intended application. To this end, researchers decellularize plant tissues by specific chemical and physical methods. Researchers use plant parts depending on their needs, for example, decellularizing the leaves, stems, and fruits. Plant tissue scaffolds are advantageous for regenerative medicine, wound healing, and bioprinting. Studies have examined various plants such as vegetables and fruits such as orchid, parsley, spinach, celery, carrot, and apple using various materials and techniques such as sodium dodecyl sulfate, Triton X-100, peracetic acid, deoxyribonuclease, and ribonuclease with varying percentages, as well as mechanical and physical techniques like freeze-thaw cycles. The process of data selection, retrieval, and extraction in this review relied on scholarly journal publications and other relevant papers related to the subject of decellularization, with a specific emphasis on plant-based research. The obtained results indicate that, owing to the cellulosic structure and vascular nature of the decellularized plants and their favorable hydrophilic and biological properties, they have the potential to serve as biological materials and natural scaffolds for the development of 3D-printing inks and scaffolds for tissue engineering. [ABSTRACT FROM AUTHOR]

In this study, bacterial cellulose was produced through the fermentation of a mixture of black tea, ginger, and sugar, and used to create bio-textile films on sugarcane-based media. Characterization included ribosomal RNA gene sequencing, FTIR spectroscopy, XRD, and SEM was used to examine surface morphology. The bio-textile films showed increasing UV resistance beyond 10 days of cultivation (T.UVA%; 0.13 ± 0.02, T.UVB%; 0.22 ± 0.01, UPF; 629 ± 2.12) and antimicrobial resistance was assessed by quantifying Colony-Forming Units (CFU), resulting in a 100% reduction in growth for both Escherichia coli and Staphylococcus aureus. Subsequently, after 15 days of cultivation, antimicrobial activity was evaluated using the disc agar diffusion method, yielding noteworthy outcomes. E. coli displayed a 25 mm zone of inhibition, S. aureus exhibited a 31 mm zone of inhibition, Candida albicans showed a 35 mm zone of inhibition, and Aspergillus niger presented a 22 mm zone of inhibition. [ABSTRACT FROM AUTHOR]

Material engineering is a fundamental issue in the applications of materials in the medical field. One of the aspects of material engineering is incorporating recognition sites on the surface of biomaterials, which plays an essential role in increasing the efficiency of tissue engineering scaffolds in various aspects. The application of peptides and antibodies to establish the recognition and adhesion sites has limitations, such as fragility and instability under physical and chemical processes. Therefore, synthetic ligands such as nucleic acid aptamers have received much attention for easy synthesis, minimal immunogenicity, high specificity, and stability under processing. Due to the effective role of these ligands in increasing the efficiency of engineered constructs in this study, the advantages of nucleic acid aptamers in tissue engineering will be reviewed. Aptamer-functionalized biomaterials can attract endogenous stem cells to wounded areas and organize their actions to facilitate tissue regeneration. This approach harnesses the body's inherent regeneration potential to treat many diseases. Also, increased efficacy in controlled release, slow and targeted drug delivery are important issues in drug delivery for tissue engineering approaches which can be achieved by incorporating aptamers in drug delivery systems. Aptamer-functionalized scaffolds have very applications, such as diagnosis of cancer, hematological infections, narcotics, heavy metals, toxins, controlled release from the scaffolds, and in vivo cell tracing. Aptasensors, as a result of many advantages over other traditional assay methods, can replace older methods. Furthermore, their unique targeting mechanism also targets compounds with no particular receptors. Targeting cell homing, local and targeted drug delivery, cell adhesion efficacy, cytocompatibility and bioactivity of scaffolds, aptamer-based biosensor, and aptamer-functionalized scaffolds are the topics that will be examined in this review study. [ABSTRACT FROM AUTHOR]

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a devastating disease threatening global wheat production. Biocontrol by beneficial microorganisms is considered an alternative to synthetic fungicide applications. This study aimed to investigate the mechanisms involved in the biocontrol of wheat stripe rust by streptomycetes. A streptomycete strain XF, isolated from the rhizospheric soil of peony, was identified as Streptomyces tauricus based on morphological characteristics and phylogenetic analysis. We determined the inhibitory effect of XF on Pst and biocontrol effect on the disease using XF fermentation filtrate (FL) and actinomycete cell suspension (AC). Results revealed that FL inhibited urediniospore germination by up to 99% and rendered a lethality rate of 61.47% against urediniospores. Additionally, crude extract of ethyl acetate phase of FL caused cytoplasm releases from urediniospores and the deformation of germ tubes. Furthermore, histochemical analyses revealed that treatments of plants with AC and FL increased reactive oxygen species, inhibited haustorium formation, and reduced the biomass of Pst in leaves. Electron microscopy showed that XF mycelium was able to colonize the leaf surface. Moreover, gene expression assays revealed that AC and FL treatments induced the expression of a number of pathogenesis-related genes in wheat leaves. Besides, in the greenhouse experiments, the control effects of AC and FL reached 65.48% and 68.25%, respectively. In the field, application of XF fermentation broth significantly reduced the disease indices of stripe rust by 53.83%. These findings suggest that XF is a potential biocontrol agent for managing wheat stripe rust disease. [ABSTRACT FROM AUTHOR]

Kombucha-derived bacterial cellulose (KBC) is a unique natural polysaccharide that has gained increasing interest in biomedical and other applications. However, the relatively low bioactivity of the product has limited its practical applications. In this work, KBC and silk nonwoven fabric (SNF) were integrated to produce a sandwich membrane through in situ growth of KBC in the presence of SNF. Scanning electron microscopy (SEM) showed that KBC grew not only on the surface of SNF but also within the fiber network of SNF. The strength and modulus of SNF were significantly increased after the integration of KBC. The KBC/SNF sandwich membrane was further impregnated with silk sericin (SS) through simple solution absorption to impart strong UV shielding property to the material, which was demonstrated by the near zero UV transmittance of the new KBC/SNF-SS membrane. SEM, Fourier transform infrared spectrometry, and X-ray diffraction results indicated the interactions between the three components. DPPH (2,2-Diphenyl-1-picrylhydrazl) radical scavenging test and cytotoxicity test showed strong antioxidant activity and biocompatibility of the new membrane due to the presence of SNF and SS. These properties make this new biocomposite membrane a promising material for healthcare and skincare applications, such as wound dressing and beauty products. [ABSTRACT FROM AUTHOR]

This study describes the synthesis of silver nanoparticles (AgNPs) using shortleaf spikesedge extract (SSE) to reduce AgNO3. Visual observation, in addition to analyses of UV-vis, EDX, XRD, FTIR, and TEM was employed to monitor the formation of AgNPs. The effects of SSE concentration, AgNO3 concentration, reaction time, pH, and temperature on the synthesis of AgNPs were studied based on the surface plasmon resonance (SPR) band. From the TEM image, highly-scattered AgNPs of quasi-spherical shape with an average particle size of 17.64 nm, were observed. For the catalytic study, the reduction of methylene blue (MB) was evaluated using two systems. A detailed batch study of the removal efficiency (%RE) and kinetics was done at an ambient temperature, various MB initial concentrations, and varying reaction time. Employing the electron relay effect in System 2, the batch study clearly highlighted the significant role of AgNPs in boosting the catalytic activity for MB removal. At 30–100 mg/L initial concentrations, MB was reduced by 100% in a very short reaction time between 1.5 and 5.0 mins. The kinetic data best fitted the pseudo-first-order model with a maximum reaction rate of 2.5715 min−1. These findings suggest the promising application of AgNPs in dye wastewater treatment. The SSE-driven AgNPs were prepared using unwanted dried biomass of shortleaf spikesedge extract (SSE) as a reducing as well as stabilizing agent. Employing the electron relay effect, the batch study clearly highlighted the significant role of SSE-driven AgNPs in boosting the catalytic activity for MB removal. At 30–100 mg/L initial concentrations, MB was reduced by 100% in a very short reaction time between 1.5 and 5.0 mins. In this sense, SSE-driven AgNPs acted as an electron relay point that behaves alternatively as acceptor and donor of electrons. The findings revealed the good catalytic performance of SSE-driven AgNPS, proving their viability for dye wastewater treatment. [ABSTRACT FROM AUTHOR]

Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of the product Huvezym® neXo 100 G/L containing an endo‐1,4‐beta xylanase, an endo‐1,4‐beta‐glucanase and a xyloglucan‐specific‐endo‐beta‐1,4‐glucanase produced by a non‐genetically modified strain of Trichoderma citrinoviride (DSM 33578) as a zootechnical additive for feed in all poultry species, ornamental birds and piglets (weaned and suckling). The information regarding the production strain did not allow to confirm its taxonomic identification. The batches used for the characterisation of the final formulations showed compliance with the minimum specifications of the additive in terms of enzyme activities but showed ratios between the enzymes lower than the ones specified for the additive. The FEEDAP Panel considered that the below‐described conclusions would apply to the final formulations of the additive as per specifications with xylanase:glucanase, xylanase:xyloglucanase and glucanase:xyloglucanase ratios of 15, 15 and 1, respectively. Based on the data available, the Panel concluded that the additive is safe for the target species, consumers and the environment. Huvezym® neXo 100 G (granulated form) is neither skin corrosive nor eye irritant but should be considered a potential skin sensitiser. Huvezym® neXo 100 L (liquid) is neither skin corrosive nor sensitising and it is not an eye irritant. Due to lack of data, no conclusions can be drawn on the skin irritation of the final formulations of the additive. Due to the proteinaceous nature of the active substances, the additive is considered a respiratory sensitiser. The FEEDAP Panel concluded that the additive has the potential to be efficacious in chickens for fattening, chickens reared for laying and breeding, and all growing poultry and ornamental birds at the minimum intended level of 1,500 EPU, 100 CU and 100 XGU/kg complete feed. Owing to the lack of sufficient data, the Panel could not conclude on the efficacy of the additive for laying hens and weaned piglets. [ABSTRACT FROM AUTHOR]

Selenium (Se) is an essential micronutrient with many beneficial effects for humans and other living organisms. Numerous microorganisms in culture systems enrich and convert inorganic selenium to organic selenium. In this study, Epichloë sp. from Festuca sinensis was exposed to increasing Na2SeO3 concentrations (0, 0.1, 0.2, 0.3, and 0.4 mmol/L) in Petri dishes with potato dextrose agar (PDA) for 8 weeks. Epichloë sp. mycelia were immediately collected after mycelial diameters were measured at 4, 5, 6, 7, and 8 weeks of cultivation, respectively. Gas chromatography-mass spectrometer (GC-MS) analysis was performed on different groups of Epichloë sp. mycelia. Different changes were observed as Epichloë sp. was exposed to different selenite conditions and cultivation time. The colony diameter of Epichloë sp. decreased in response to increased selenite concentrations, whereas the inhibitory effects diminished over time. Seventy-two of the 203 identified metabolites did not differ significantly across selenite treatments within the same time point, while 82 compounds did not differ significantly between multiple time points of the same Se concentration. However, the relative levels of 122 metabolites increased the most under selenite conditions. Specifically, between the 4th and 8th weeks, there were increases in 2-keto-isovaleric acid, uridine, and maltose in selenite treatments compared to controls. Selenium increased glutathione levels and exhibited antioxidant properties in weeks 4, 5, and 7. Additionally, we observed that different doses of selenite could promote the production of carbohydrates such as isomaltose, cellobiose, and sucrose; fatty acids such as palmitoleic acid, palmitic acid, and stearic acid; and amino acids such as lysine and tyrosine in Epichloë sp. mycelia. Therefore, Epichloë sp. exposed to selenite stress may benefit from increased levels of some metabolite compounds. [ABSTRACT FROM AUTHOR]

The quality control of the bacterial cellulose (BC) production has been facing challenges due to the genetic stability of bacterial strains, which is often overlooked or underestimated. Thus, its commercialized application is limited. Therefore, a bacterial strain FM883 with a 16S rRNA sequence 97% identical to Komagataeibacter xylinus NBRC15237T was isolated from kombucha tea. Cultivation of FM883 was conducted in series to observe the morphology and BC yield among different generations from 1st generation to 30th generation. The results show that FM883 can efficiently produce BC in modified Hestrin-Schramn media at the 30th generation (163.5 ± 0.3 g/L), which was even higher than the 1st generation (157.6 ± 0.3 g/L). This indicated that FM883 has strong genetic stability. Furthermore, several characterizations of the BC indicated that the quality of the BC biosynthesized by FM883 was good with excellent thermostability. With such strong genetic stability, and properties, as well as sufficiently high consistency and high yield, BC biosynthesized by FM883 had demonstrated excellent production quality control, which is desired for commercial manufacturing. [ABSTRACT FROM AUTHOR]

Silibinin is considered as a functionalized flavonoid and natural substitute for synthetic anticancer drugs like doxorubicin, paclitaxel, etc. However, the principle reasons for restraining the bioavailability of silibinin are low aqueous solubility, less penetration into the epithelial cells of the intestine and rapid systemic elimination. This present work focused on the development of inclusion complexes of silibinin with hydroxypropyl-β-cyclodextrin and further incorporated into hybrid liposomes to improve solubility, bioavailability and stability as well as to explore the anticancer activity of silibinin. Hybrid liposomes were prepared by thin lipid film hydration method. Molecular docking studies projected for the formation of complex with physicochemical structural changes which were confirmed by ATR-FTIR, DSC, XRD, 1H NMR and SEM studies. The particle size distribution of hybrid liposomal formulations was obtained in the range of 200–500 nm with zeta potential more than – 30 mV. The release of silibinin from hybrid liposomes was maximum (75.40% ± 0.73) with better solubility (73.95 mg/mL) and relative bioavailability (4.52). This drug delivery system exhibited higher cytotoxicity against kidney cancer cell line (A-498) through endocytic internalization into the cells and good pharmacokinetic properties as compared with silibinin. In near future, hybrid liposomes can be a promising carrier for increasing the solubility, bioavailability and stability of silibinin. [ABSTRACT FROM AUTHOR]

There is increasing concern regarding the existing sheep wool processing technology in the textile industry owing to the enormous volume of toxic effluents generated. The application of supercritical carbon dioxide (scCO2) in sheep wool processing is cleaner and increases wool fiber production while avoiding toxic effluent generation. scCO2 is a novel clean technology that can be utilized in sheep processing for sterilization, cleaning, and drying sheep wool at the same time. In the present study, scCO2 was used to treat sheep wool with varying pressure, temperature, and treatment time. These parameters influence the scCO2 treatment of sheep wool fiber through the inactivation of microorganisms and improvement of the whiteness index. The identification of bacteria in sheep wool was carried out based on biochemical analysis by molecular means, using 16s rRNA sequencing. It was found that scCO2 completely inactivated the microorganisms present in sheep wool and potentially enhanced the percentage whiteness index at the highest pressure of 30 MPa, temperature of 80°C, and treatment time of 80 min. Several analytical methods were employed to assess the physicochemical, thermal, and morphological properties of untreated and scCO2 treated sheep wool fibers. The results show that scCO2 effectively removes the impurities and completely inactivates the microorganisms present in sheep wool. The findings of the present study reveal that scCO2 can be utilized as an alternative treatment technology for sheep wool processing in the textile industry. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) exhibits a unique combination of porosity, tensile strength, reticulated crystal structure and biocompatibility useful for many applications in the food, biomedical and other industries. Polysaccharide addition has been shown to improve the production and the mechanical properties of BC nanocomposites. This study examined the effect of pullulan on BC fermentation as well as the co-culturing of the BC producer with Aureobasidium pullulans, a fungal strain that produces pullulan as an exopolysaccharide. Results showed that a 1% pullulan addition improved Young's modulus of BC pellicles for sixfold. Addition of pullulan at 1.5% and 2% levels could increase the BC production from 0.447 to 0.814 and 1.997 g/L, respectively. The co-culture fermentation demonstrated a mixed effect on the aggregation and bundling of BC while resulting in a significant improvement in mechanical properties. The study provided a polysaccharide additive and a novel fermentation method to produce BC with improved properties. [ABSTRACT FROM AUTHOR]

Current research in industrial microbiology and biotechnology focuses on the production of biodegradable microbial polymers as an environmentally friendly alternative to the still dominant fossil hydrocarbon-based plastics. Bacterial cellulose (BC) is important among microbial polymers due to its valuable properties and broad applications in variety of fields from medical to industrial technologies. However, the increase in BC production and its wider deployment is still limited by high costs of traditionally used raw materials. It is therefore necessary to focus on less expensive inputs, such as agricultural and industrial by-products or waste including the more extended use of glycerol. It is the environmentally harmful by-product of biofuel production and reducing it will also reduce the risk of environmental pollution. The experimental data obtained so far confirm that glycerol can be used as the renewable carbon source to produce BC through more efficient and environmentally friendly bioprocesses. This review summarizes current knowledge on the use of glycerol for the production of commercially prospective BC, including information on producer cultures, fermentation modes and methods used, nutrient medium composition, cultivation conditions, and bioprocess productivity. Data on the use of some related sugar alcohols, such as mannitol, arabitol, xylitol, for the microbial synthesis of cellulose are also considered, as well as the main methods and applications of glycerol pre-treatment briefly described. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) is a polymer with interesting conformation and properties. BC can be obtained in different shapes and is easily modified by chemical and physical means, so its applications in the production of new materials and nanocomposites for different purposes have been in the focus of many research projects. However, one of the major challenges to address in bacterium-derived polymer technology is to find suitable carbon sources as substrates that are cheap and do not compete with food production for achieving large scale industrial applications. Agricultural wastes are defined as the residues from the growing and processing of raw agricultural products such as crops, fruits, vegetables and dairy products. Their composition can vary depending on the type of agricultural activity and harvesting conditions, but these residues are suitable for the production of BC. The aim of this review is to give insight into the production of BC using agro-wastes and an overview of the most interesting and novel applications of this biopolymer in different areas i.e. environmental applications, optoelectronic and conductive devices, food ingredients and packaging, biomedicine, and 3D printing technology. [ABSTRACT FROM AUTHOR]

The use of natural compounds in medicine for the treatment of diseases started since ancient days. Though many natural compounds exhibit potent pharmacological activity, their medicinal application is limited by low solubility, permeability or stability. Therefore, pharmaceutical scientists are developing drug delivery systems and carriers that allow better efficacy and clinical success. For instance, nanocarriers, owing to their small size and unique surface properties, allow successful delivery of various drugs by modifying solubility, permeability and pharmacokinetics. Nanocarriers preserve encapsulated molecules from degradation and, in turn, enhance stability. Here, we review nanocarriers with focus on natural molecules including thymoquinone, resveratrol, artemisinin, silymarin, natural antibiotics and natural extracts, which are used in different disease conditions, for example Alzheimer's, diabetes, microbial infections, inflammation and psoriasis. [ABSTRACT FROM AUTHOR]

Highlights: Fluorescence lifetime imaging microscopy (FLIM) applications for cancer diagnosis and treatment monitoring combined with reduced form of nicotinamide adenine dinucleotide, Förster resonance energy transfer (FRET), and biosensors are reviewed. Principles of FLIM, previous clinical applications, and development history are introduced. The current challenges and prospects for the potential of FLIM for cancer diagnosis and promotion of the effect of anti-cancer treatment are discussed.Fluorescence lifetime imaging microscopy (FLIM) has been rapidly developed over the past 30 years and widely applied in biomedical engineering. Recent progress in fluorophore-dyed probe design has widened the application prospects of fluorescence. Because fluorescence lifetime is sensitive to microenvironments and molecule alterations, FLIM is promising for the detection of pathological conditions. Current cancer-related FLIM applications can be divided into three main categories: (i) FLIM with autofluorescence molecules in or out of a cell, especially with reduced form of nicotinamide adenine dinucleotide, and flavin adenine dinucleotide for cellular metabolism research; (ii) FLIM with Förster resonance energy transfer for monitoring protein interactions; and (iii) FLIM with fluorophore-dyed probes for specific aberration detection. Advancements in nanomaterial production and efficient calculation systems, as well as novel cancer biomarker discoveries, have promoted FLIM optimization, offering more opportunities for medical research and applications to cancer diagnosis and treatment monitoring. This review summarizes cutting-edge researches from 2015 to 2020 on cancer-related FLIM applications and the potential of FLIM for future cancer diagnosis methods and anti-cancer therapy development. We also highlight current challenges and provide perspectives for further investigation. [ABSTRACT FROM AUTHOR]

The paper presents the results of phytopathogenic fungi determination in bare-root forest nurseries of Middle Siberia. Genetic analysis of pathogenic microflora of Pinus sylvestris L., Pinus sibirica Du Tour and Picea obovata Ledeb. seedlings allowed identification of 17 genera of micromycetes: Phoma Sacc., Lophodermium Chevall., Sclerophoma Höhn. (teleomorph Sydowia Bres.), Cladosporium Link, Alternaria Nees, Typhula (Pers.) Fr. etc. Most frequently detected fungi represented genera Phoma (23.7%) and Lophodermium (23.6%). Pinus sylvestris L. seedlings harboured the highest diversity of fungal taxa. Seven genera of microscopic fungi (Phoma sp., Didymella sp., Alternaria sp., Cladosporium sp., Lophodermium sp., Gremmenia sp., Sclerophoma sp.) were detected in all studied forest zones: taiga, forest-steppe and Southern- Siberian mountain. The obtained results demonstrate the usefulness of DNA analysis for the identification of phytopathogenic fungi in forest nurseries of Middle Siberia with several implications for increasing the efficacy of forest management. [ABSTRACT FROM AUTHOR]

Monitoring of cell metabolism represents an important application area for fluorescence lifetime imaging microscopy (FLIM). In particular, assessment of mitochondrial membrane potential (MMP) in complex three‐dimensional multicellular in vitro, ex vivo, and in vivo models would enable improved segmentation and functional discrimination of cell types, directly report on the mitochondrial function and complement the quenched‐phosphorescence detection of cellular O2 and two‐photon excited FLIM of endogenous NAD(P)H. Here, we report the green and orange‐emitting fluorescent dyes SYTO and tetramethylrhodamine methyl ester (TMRM) as potential FLIM probes for MMP. In addition to nuclear, SYTO 16 and 24 dyes also display mitochondrial accumulation. FLIM with the culture of human colon cancer HCT116 cells allowed observation of the heterogeneity of mitochondrial polarization during the cell cycle progression. The dyes also demonstrated good performance with 3D cultures of Lgr5‐GFP mouse intestinal organoids, providing efficient and quick cell staining and compatibility with two‐photon excitation. Multiplexed imaging of Lgr5‐GFP, proliferating cells (Hoechst 33342‐aided FLIM), and TMRM‐FLIM allowed us to identify the population of metabolically active cells in stem cell niche. TMRM‐FLIM enabled to visualize the differences in membrane potential between Lgr5‐positive and other proliferating and differentiated cell types. Altogether, SYTO 24 and TMRM dyes represent promising markers for advanced FLIM‐based studies of cell bioenergetics with complex 3D and in vivo models. © 2019 International Society for Advancement of Cytometry [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) membrane can be architected to covalently immobilize biomolecules, generating materials with new functionality. The processes of purification (via alkaline treatment) and chemical modification (via NaIO4) to the wet BC membrane is the innovation of this work. This wet oxidized BC (OxBC) membrane could act as a support matrix for covalent immobilization of enzymes. BC produced over 5 days of static fermentation, followed by purification with K2CO3 (BC-5d-K2CO3) was selected for our study due to high porosity and surface area, which are properties that favor its chemical modification. This wet BC membrane proven suitable for NaIO4 oxidation. Time and temperature conditions were evaluated in the oxidation reaction, with oxidation BC (OxBC) performed at 1% (w/v) NaIO4 for 6 h at 55 °C under most advantageous conditions, as it provided 50% oxidation degree and preserved its morphological structure. BC and OxBC were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Scanning electron microscopy, mechanical test, and thermal analysis. The oxidation reaction decreased BC crystallinity, tensile strength, and thermal stability and compacted the cellulose layers. BC and OxBC showed non-cytotoxicity. Fourier transform infrared confirmed that OxBC can covalently immobilize papain and that after immobilization the enzyme showed a recovered enzymatic activity of 93.1%. In addition, the oxidized membrane presented greater amount of immobilized papain in its study than BC, proving to be a more efficient support for enzymatic immobilization. [ABSTRACT FROM AUTHOR]

Fibers of bacterial cellulose were obtained for the first time from solutions in N-methylmorpholine N-oxide (NMMO) by using the concept of solid-phase dissolution of bacterial cellulose. The mechanism of solid-phase dissolution of bacterial cellulose in NMMO is examined with due regard to the structural and morphological characteristics of native bacterial cellulose. By investigating the structure of the fibers it was possible to reveal the different orientation of the main diffraction planes of the outer shell and inner part of the fiber reflecting the structural aspect of the shell–core morphology. The fibrillar morphology of the fiber was established by scanning electron microscopy. The thermal characteristics of the fibers of bacterial cellulose differ radically from the characteristics of fibers of plant origin in the preponderance of condensation processes that produce exo effects on the thermograms and lead to increase of the carbon residue. The mechanical characteristics of the obtained fibers were characterized. [ABSTRACT FROM AUTHOR]

Protein-modified scaffolds have ability to provide biological functionality due to the similarity in structure of natural extracellular matrix (NECM) in tissues. In this paper, soy protein was selected to modify bacterial cellulose (BC) electrospun nanofiber scaffold prepared by fabricating BC nanofiber via electrospinning followed by ultrasound-induced self-assembly method. The modified nanofiber scaffold has multi-size distribution composed of BC electrospun nanofiber with diameter ranged from 80 to 360 nm and soy protein nanoparticles layer on the surface, which mimics the structure of NECM. The surface morphology and specific surface areas of soy protein modified BC electrospun nanofiber scaffold were investigated by scanning electronic microscopy and Brunauer–Emmett–Teller test. The structure, crystallinity, thermal stability, mechanical properties and hydrophilicity were characterized by Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, thermogravimetric analysis, dynamic mechanical analysis, tensile test and water contact angle measurement. Soy protein surface modification does not obviously affect the crystalline structure of BC electrospun nanofiber. However, an increase in thermal stability and toughness can be observed. After soy protein surface modification, the nanofiber scaffold became more stretchable with the elongation at break greatly increased about 110% from 6.55 ± 0.71 to 13.81 ± 1.12%. The biodegradability and cytocompatibility of soy protein modified BC electrospun nanofiber scaffold were preliminarily evaluated by in vitro tests. Soy protein modified BC electrospun nanofiber scaffold exhibited higher biodegradation rate in enzyme solution and better biocompatibility. The as-prepared soy protein modified BC electrospun nanofiber scaffold is more bioactive and promising as bone tissue engineering scaffold. [ABSTRACT FROM AUTHOR]

Abstract: Bacterial cellulose nanocrystals (BCNCs) have hydrophilic surfaces due to hydroxyl groups but are water-insoluble. The carboxymethylation improves the solubility of cellulose in polar media through the insertion of carboxymethyl groups. This study aims to evaluate the use of two different alcoholic solvents in the carboxymethylation reaction of BCNCs: ethanol and isopropanol. BCNCs were obtained under two hydrolysis conditions: sulfuric acid (BCNC-S) and combination of sulfuric and hydrochloric acids (BCNC-S/Cl). Two techniques (NMR and titration) were used to determine the degree of substitution (DS) values. Carboxymethylation of BCNC-S/Cl led to high DS compared to BCNC-S and the use of isopropanol promoted an even greater DS. The thermal properties were not affected after the chemical modification. However, functionalization provided an increase in the negative charge density at the surface of nanostructures and a change in the crystal structure (cellulose type Iα for amorphous), making this material a potential polyanion for the synthesis of polyelectrolyte complexes (PECs). The micrographs showed that the nanocrystals became soluble after carboxymethylation. Carboxymethylated bacterial cellulose nanocrystals hydrolyzed through the mixture of inorganic acids and modified using isopropanol (CBCNC-S/Cl-IPA) was a suitable polyanion to produce PECs with chitosan. The PECs produced had particle size ranging from 276 to 588 nm and zeta potential ranging from − 24.3 to + 39.0 mV.Graphical abstract: [ABSTRACT FROM AUTHOR]

The cytotoxic and antitumor effect of liposomal form of silibinin was studied. It was shown that the liposomal silibinin reveals more pronounced cytotoxic activity in vitro against HeLa (cervix carcinoma), HT1080 (fibrosarcoma), and MCF-7 (breast adenocarcinoma) human tumor cell lines compared with non-liposomal silibinin. In vivo experiments demonstrated a possibility of parenteral use of the liposomal form. It was demonstrated that intravenous administration of liposomal silibinin has a significant antitumor effect in vivo against murine adenocarcinoma of Ca 755 and leads to inhibition of tumor growth (53.6%) and an increase (49.4%) in the mean life span of experimental animals compared to untreated control and animals receiving non-liposomal forms (free silibinin and its mixture with lecithin) administered orally. [ABSTRACT FROM AUTHOR]

This investigation was conducted in 2005/2006 and 2006/2007 to test 235 barley lines plus two varieties Giza 127 and Giza 128 for resistance and susceptibility to Fusarium graminearum. All screened barley lines showed varied significant degrees of infestation to root rot pathogen. A screening system is described for identifying barley lines which are effective in controlling resistant or susceptible lines. By detecting small but consistent differences in root rot severity, the bioassay proved effective in large-scale screening for partial resistance: already 335 barley lines and two varieties have been screened. We found five groups (7.12%), 22 barley lines and both varieties are resistant (R) (8.31%); 28 barley lines are moderately resistant (MR) (19.29%); 65 barley lines are moderately susceptible (MS) (27.89%); 94 barley lines are susceptible (S) and (37.39%) 126 barley lines are highly susceptible (HS). The high degree of precision makes this an invaluable tool in the understanding of pathogen aggressiveness, host specialisation and parasitic fitness. Disease scale was strongly negative and had moderate correlation with germination (-0.309** and -0.649**) under normal and disease treatment. The correlation between yield and normal and disease treatment during two seasons was strong and negative (-0.834** and -0.847**, respectively were detected). [ABSTRACT FROM AUTHOR]