Types Of Cellulose Research Articles

Recent Progress on Tailoring the Biomass-Derived Cellulose Hybrid Composite Photocatalysts.

Biomass-derived cellulose hybrid composite materials are promising for application in the field of photocatalysis due to their excellent properties. The excellent properties between biomass-derived cellulose and photocatalyst materials was induced by biocompatibility and high hydrophilicity of the cellulose components. Biomass-derived cellulose exhibited huge amount of electron-rich hydroxyl group which could promote superior interaction with the photocatalyst. Hence, the original sources and types of cellulose, synthesizing methods, and fabrication cellulose composites together with applications are reviewed in this paper. Different types of biomasses such as biochar, activated carbon (AC), cellulose, chitosan, and chitin were discussed. Cellulose is categorized as plant cellulose, bacterial cellulose, algae cellulose, and tunicate cellulose. The extraction and purification steps of cellulose were explained in detail. Next, the common photocatalyst nanomaterials including titanium dioxide (TiO2), zinc oxide (ZnO), graphitic carbon nitride (g-C3N4), and graphene, were introduced based on their distinct structures, advantages, and limitations in water treatment applications. The synthesizing method of TiO2-based photocatalyst includes hydrothermal synthesis, sol-gel synthesis, and chemical vapor deposition synthesis. Different synthesizing methods contribute toward different TiO2 forms in terms of structural phases and surface morphology. The fabrication and performance of cellulose composite catalysts give readers a better understanding of the incorporation of cellulose in the development of sustainable and robust photocatalysts. The modifications including metal doping, non-metal doping, and metal-organic frameworks (MOFs) showed improvements on the degradation performance of cellulose composite catalysts. The information and evidence on the fabrication techniques of biomass-derived cellulose hybrid photocatalyst and its recent application in the field of water treatment were reviewed thoroughly in this review paper.

Development of Squalene-Based Oil-in-Water Emulsion Adjuvants Using a Self-Emulsifying Drug Delivery System for Enhanced Antigen-Specific Antibody Titers.

A recombinant protein cannot induce sufficient immune response by itself. Various substances, including cytokine and mineral, have been used as adjuvants to enhance the immunogenicity and efficacy of vaccines; however, most of them induce excessive immune responses or exhibit cytotoxicity. In this study, a self-emulsifying drug delivery system (SEDDS), an isotropic mixture of oil, surfactant, and solvent, was designed for oil-in-water emulsions as a non-toxic adjuvant to increase immune response to antigens. Squalene-based oil-in-water emulsions were prepared by SEDDS to assess its value as an adjuvant. Fifteen emulsions (F1-F15) were prepared by stirring two types of surfactants (Span® 85 and Kolliphor® RH40), and squalene and carboxymethyl cellulose (CMC) were added at different ratios. The physical properties and viscosity of the 15 emulsions were evaluated by measuring droplet size, zeta potential, and polydispersity index. The toxic effect of emulsions was assessed by acute toxicity test in mice. Mice were immunized twice with 1:1 mixtures of antigen and adjuvant (15 emulsions, phosphate-buffered saline, and commercial alum-based adjuvant). Antigen-specific antibody titers from immunized mice serum were measured by an indirect enzyme-linked immunosorbent assay. All emulsions exhibited droplet sizes ranging from 322 to 812 nm and maintained zeta potential values between -30 mV to -10 mV for 4 weeks, indicating good physical stability as a vaccine adjuvant. Additionally, all emulsions were non-toxic, and they induced humoral immunity at a similar level compared to commercial alum-based adjuvant in the first immunization. However, 12% squalene-based oil-in-water emulsion containing 0.5% of ultra-high viscosity CMC (F15) showed significantly higher immune response than a commercial adjuvant in the second immunization. Squalene-based oil-in-water emulsions could be conveniently prepared using SEDDS technique and are non-toxic and stable at room temperature storage. Moreover, squalene-based oil-in-water emulsions show enhanced immune induction with antigen; hence, they can possibly be used as effective adjuvants.

Insoluble dietary fiber of pear fruit pomace (Pyrus ussuriensis Maxim) consumption ameliorates alterations of the obesity-related features and gut microbiota caused by high-fat diet

In this study, IDF from Pyrus ussuriensis Maxim pomace (PUIDF) was prepared, and its routine constituents as well as physicochemical properties and structure were analyzed. Moreover, the effect of PUIDF on obesity and gut microbiota (GM) through a high-fat diet (HFD) mouse model was investigated. The results demonstrated that PUIDF had a loose and porous surface structure and typical cellulose polysaccharide functional groups with good water holding, oil holding and swelling capacity, as well as glucose and cholesterol adsorption performance in vitro. PUIDF could significantly reduce weight gain and lipid and cholesterol levels in HFD-induced obese mice. More importantly, PUIDF intervention greatly improved the diversity of GM in mice, as well as regulated intestinal microbiota composition and increasing the abundance of short-chain fatty acid producing bacteria. These results suggest that PUIDF may have a positive effect to alleviate hyperlipidemia and improve intestinal bacterial ecosystems.

Use of Fourier Series in X-ray Diffraction (XRD) Analysis and Fourier-Transform Infrared Spectroscopy (FTIR) for Estimation of Crystallinity in Cellulose from Different Sources

Cellulose crystallinity can be described according to the crystal size and the crystallinity index (CI). In this research, using Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) methods, we studied the crystallinity of three different types of cellulose: banana rachis (BR), commercial cellulose (CS), and bacterial cellulose (BC). For each type of cellulose, we analyzed three different crystallization grades. These variations were obtained using three milling conditions: 6.5 h, 10 min, and unmilled (films). We developed a code in MATLAB software to perform deconvolution of the XRD data to estimate CI and full width at half-maximum (FWHM). For deconvolution, crystalline peaks were represented with Voigt functions, and a Fourier series fitted to the amorphous profile was used as the amorphous contribution, which allowed the contribution of the amorphous profile to be more effectively modeled. Comparisons based on the FTIR spectra and XRD results showed there were no compositional differences between the amorphous samples. However, changes associated with crystallinity were observed when the milling time was 10 min. The obtained CI (%) values show agreement with values reported in the literature and confirm the effectiveness of the method used in this work in predicting the crystallization aspects of cellulose samples.

Preparation of Chemically Resistant Cellulose Benzoate Hollow Fiber Membrane via Thermally Induced Phase Separation Method.

For the first time, we have successfully fabricated microfiltration (MF) hollow fiber membranes by the thermally induced phase separation (TIPS) and non-solvent induced phase separation (NIPS) methods using cellulose acetate benzoate (CBzOH), which is a cellulose derivative with considerable chemical resistance. To obtain an appropriate CBzOH TIPS membrane, a comprehensive solvent screening was performed to choose the appropriate solvent to obtain a membrane with a porous structure. In parallel, the CBzOH membrane was prepared by the NIPS method to compare and evaluate the effect of membrane structure using the same polymer material. Prepared CBzOH membrane by TIPS method showed high porosity, pore size around 100 nm or larger and high pure water permeability (PWP) with slightly low rection performance compared to that by NIPS. On the contrary, CBzOH membranes prepared with the NIPS method showed three times lower PWP with higher rejection. The chemical resistance of the prepared CBzOH membranes was compared with that of cellulose triacetate (CTA) hollow fiber membrane, which is a typical cellulose derivative as a control membrane, using a 2000 ppm sodium hypochlorite (NaClO) solution. CBzOH membranes prepared with TIPS and NIPS methods showed considerable resistance against the NaClO solution regardless of the membrane structure, porosity and pore size. On the other hand, when the CTA membrane, as the control membrane, was subjected to the NaClO solution, membrane mechanical strength sharply decreased over the exposure time to NaClO. It is interesting that although the CBzOH TIPS membrane showed three times higher pure water permeability than other membranes with slightly lower rejection and considerably higher NaClO resistance, the mechanical strength of this membrane is more than two times higher than other membranes. While CBzOH samples showed no change in chemical structure and contact angle, CTA showed considerable change in chemical structure and a sharp decrease in contact angle after treatment with NaClO. Thus, CBzOH TIPS hollow fiber membrane is noticeably interesting considering membrane performance in terms of filtration performance, mechanical strength and chemical resistance on the cost of slightly losing rejection performance.

Physicochemical Characteristics of Soluble Dietary Fiber Obtained from Grapefruit Peel Insoluble Dietary Fiber and Its Effects on Blueberry Jam.

Appropriate modification methods can increase the proportion of soluble dietary fiber (SDF). In this study, grapefruit peel insoluble dietary fiber (GP-IDF) was modified with the combined microwave and enzymatic method to obtain SDF. With regard to structural characterization, SDF from grapefruit peel IDF (GP-IDF-SDF) presented as a flat sheet with cracks, composed of a typical cellulose type I crystal, and had good stability below 200 °C. Galacturonic acid, arabinose and glucuronic acid were the main monosaccharide compositions, indicating that pectin might have been the principal component. Moreover, GP-IDF-SDF was excellent in water retention capacity (13.43 ± 1.19 g/g), oil retention capacity (22.10 ± 0.85 g/g) and glucose adsorption capacity (14.49 ± 0.068 mg/g). Thereafter, the effects of GP-IDF-SDF and commercial pectin addition on the color, rheology, texture and sensory properties of blueberry jam were compared. The results showed that the color of jam with GP-IDF-SDF was lighter. The addition of GP-IDF-SDF had less effects on the viscosity and gel strength of jam, but it enhanced the stability of jam. According to sensory data, the color, texture and spreadability of jam with GP-IDF-SDF or pectin were improved and more acceptable. Overall, GP-IDF-SDF had functional characteristics and played a positive role in jam, and it is expected to be a candidate for the development of functional food ingredients.

Phenol Liquefaction of Waste Sawdust Pretreated by Sodium Hydroxide: Optimization of Parameters Using Response Surface Methodology.

In this study, a two-step method was used to realize the liquefaction of waste sawdust under atmospheric pressure, and to achieve a high liquefaction rate. Specifically, waste sawdust was pretreated with NaOH, followed by liquefaction using phenol. The relative optimum condition for alkali-heat pretreatment was a 1:1 mass ratio of NaOH to sawdust at 140 °C. The reaction parameters including the mass ratio of phenol to pretreated sawdust, liquefaction temperature, and liquefaction time were optimized by response surface methodology. The optimal conditions for phenol liquefaction of pretreated sawdust were a 4.21 mass ratio of phenol to sawdust, a liquefaction temperature of 173.58 °C, and a liquefaction time of 2.24 h, resulting in corresponding liquefied residues of 6.35%. The liquefaction rate reached 93.65%. Finally, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) were used to analyze untreated waste sawdust, pretreated sawdust, liquefied residues, and liquefied liquid. SEM results showed that the alkali-heat pretreatment and liquefaction reactions destroyed the intact, dense, and homogeneous sample structures. FT-IR results showed that liquefied residues contain aromatic compounds with different substituents, including mainly lignin and its derivatives, while the liquefied liquid contains a large number of aromatic phenolic compounds. XRD showed that alkali-heat pretreatment and phenol liquefaction destroyed most of the crystalline regions, greatly reduced the crystallinity and changed the crystal type of cellulose in the sawdust.

Effects of adding methods and modification types of cellulose on the physicochemical properties of starch/PBAT blown films

This study revealed the relationship between cellulose types/adding methods and film properties, in which sodium carboxymethyl cellulose (CMC), hydroxypropyl methyl cellulose (HPMC), and microcrystalline cellulose (MCC) were added into starch/PBAT blown films in powder, aqueous solution, and emulsion forms, respectively. Cellulose interacted with starch networks via hydrogen bonds, and those added in emulsion form made more homogeneous film morphologies. MCC emulsion enhanced the film strength (40%) and modulus (149%) to the greatest extent, while comprehensively, HPMC emulsion possessed better reinforcement effects on the films, which increased mechanical properties (31% ~ 100%), moisture barrier (20%), oxygen barrier (93%), surface hydrophobicity (20%), as well as water resistance (12% ~ 76%). Findings supported the application of cellulose in high-throughput biodegradable films, and the high-content starch/PBAT blown films reinforced by HPMC emulsion had great potential in commercial packaging fields.

Preparation and Characterization of Cellulose Nanofibrils from Lignocellulose Using a Deep Eutectic Solvent Followed by Enzymatic Treatment

Lignocellulose nanofibrils (LCNFs) were prepared using a two-step deep eutectic solvent (DES) and enzymatic pretreatment followed by mechanical defibrillation, and we examined the effects of enzymatic pretreatment conditions on different characteristics of the LCNFs thus obtained. The LCNFs yielded using the two-step DES pretreatment (Enz-LCNF) exhibited a well-defibrillated entangled web-like structure with an average fiber diameter ranging from 15.7 to 20.4 nm. Furthermore, we found that the average diameter and filtration time of the Enz-LCNFs decreased with an increase in enzyme concentration and enzymatic treatment time, whereas we detected a concomitant reduction in the tensile strength of the Enz-LCNF sheets. The Enz-LCNFs were characterized by a typical cellulose I structure, thereby indicating that the enzymatic treatment causes very little damage to the crystalline form.

Green production of lignocellulose nanofibrils by FeCl3-catalyzed ethanol treatment

The traditional strategy for isolating cellulose nanomaterials requires various chemicals and a high energy input, while achieving a low product yield owing to lignin removal during pulping and bleaching. Here, we propose a green ethanol pretreatment process with a synergistic effect using ultrasound and FeCl3 to produce lignocellulose nanofibrils (LCNF) with a high yield (over 67 %) from thermomechanical pulp. Notably, a high-aspect-ratio LCNF with uniformly distributed lignin nanoparticles, a high lignin content, and excellent thermostability (Tmax > 330 °C) with a typical cellulose I crystalline structure were successfully obtained. In addition, reduced distillation can easily retrieve the FeCl3 solution and ethanol, reducing reagent waste. In general, FeCl3-catalyzed ethanol pretreatment can serve as a sustainable and environmentally friendly approach for converting sustainable lignocelluloses into high value-added nanomaterials. Moreover, the obtained LCNF can be applied in diverse fields.

Kinetic assessment of the thermal decomposition of hemp fiber and the impact of pretreatments

Motivated by green building applications (bio-composite and insulation materials), thermogravimetric and kinetic analysis is applied to investigate the thermal degradation of cleaned hemp fibers (F), obtained after water retting and mechanical decortication of dioecious plant stalks, and technical fiber (TF), obtained after field retting of monoecious plant stalks. Celluloses (microcrystalline PH105 cellulose and cotton linter cellulose) are used for comparison. F and TF dynamic curves are well described by a four-step scheme. The dominant one concerns pseudo-cellulose decomposition with the release of 70 and 54 mass% volatile matter, respectively. The corresponding activation energies are in the range of typical cellulose values (223 and 211 KJ mol−1). Fiber pretreatments (water washing, mild torrefaction, mercerization) modify the pseudo-cellulose content (release of 73–80 mass% volatile matter) and properties, as testified by the higher activation energies (229–248 kJ mol−1) of the decomposition process. The decortication method also contributes remarkably to the characteristics of the fiber cellulose.

Influence of Temperature and pH Conditions on the Swelling Properties of Rice Straw Derived Cellulose Hydrogel

Cellulose, one of the renewable and biodegradable polymers, has been extensively studied as a raw material for a newly and fully bio-based hydrogel. The synthesis of bio-hydrogel is based on the dissolution of extracted cellulose from rice straw in tetrabutylphosphonium hydroxide (TBPH) solvent followed by the gelation using epichlorohydrin (ECH) crosslinkers. The success of the extraction of cellulose from rice straw was evaluated by characteristic peaks of cellulose in Fourier Transform Infrared Spectroscopy (FTIR) spectrum. The hydrogel formation mechanism was investigated in this article, as well as the evaluation of swelling properties under different temperature and pH conditions. As hydrogel exhibited thermal and pH sensitive behavior, the highest swelling capacity was found at pH 7.0 and 60 ºC. The characterization of hydrogel was examined by Fourier Transform Infrared Spectroscopy (FTIR) and thermal analysis (TGA), indicating that the rice straw derived cellulose hydrogel was cellulose type II, similar to others hydrogels. The morphology of extracted cellulose and hydrogel were investigated by Scanning Electron Microscope (SEM). The hydrogel exhibited porousity structure with very large pore size that surrounded by cellulose/ECH layers. The purity of the hydrogel was determined through the amount of water immersed in the hydrogel for one day by Liquid Nuclear Magnetic Resonance (NMR) for the residual TBPH determination.

The role of oil concentration on the rheological properties, microstructure, and in vitro digestion of cellulose ether emulsions

The effect of oil concentration (from 5 to 47%) and type of cellulose ether on the rheological properties (flow and linear viscoelasticity), microstructure and oil digestion in o/w cellulose ether emulsions were investigated in the study. Three types of cellulose ethers were used: a hydroxypropyl methylcellulose (HPMC) and two methylcelluloses (MC) with different degrees of methoxyl content. All the emulsions showed shear thinning behaviour. The increase in oil concentration increase the emulsion's viscosity, the viscoelastic moduli G′ and G″, and decreases the loss tangent. The greatest viscosity and viscoelasticity was in the MC with the highest methoxyl content. Oil digestibility was determined by a titration method during in vitro digestion. Compared to a whey protein emulsion (control), the cellulose ether emulsions required a lower NaOH, which indicates lower free fatty acid generation and lower fat digestion. In the cellulose ether emulsions, this decrease in oil digestion was found at all the oil concentrations. A difference in oil digestion kinetics was found between the cellulose ether emulsion (linear) and the control (logarithmic), which was associated to a saturation in the digestive system in the whey protein emulsion. The microstructure after in vitro digestion showed practically no fat globules in the whey protein emulsion, whereas fat globules were observed in the cellulose ether emulsions, which confirms the highest oil digestion in the control emulsion. Cellulose ether emulsions with a wide variety of rheological properties can be obtained by varying cellulose type and oil concentration, with the barrier against fat digestion effective at low and high oil concentrations. • The effect of oil contentin rheology, microstructure and digestion of emulsions were studied. • Viscosity and viscoelasticity increased with oil concentration. • Cellulose ethers showed lower digestibility than a whey protein control. • Different oil digestion kinetics was found among cellulose ether and whey protein control. • Saturation occurs in the whey protein emulsion at higher oil concentration.

The Effect of Humidity on the Dissolution Kinetics and Tablet Properties of Immediate-Release Tablet Formulation Containing Lamotrigine.

This study aims to find the effects of high (75%) and low (30%) humidity conditions and its correlation with formulation composition on dissolution kinetics of lamotrigine (LMT) from prepared immediate-release tablets during one- and four-week periods. Two types of fillers microcrystalline cellulose (MCC) or anhydrous lactose (LAC), disintegrant sodium starch glycolate (NaSG, 0.5% or 4%), and lubricant magnesium stearate (MgST, 0.25% or 5%) were used. A three-factor two-stage complete factorial design (23) was used to assess the influence of the composition of the tested formulations. The tablets were produced by direct compression and characterized using a disintegration test, a resistance to crushing test, and dissolution tests (pH 1.2 and pH 6.8). Using Design Expert software, it was concluded that in addition to the effect of fillers on pH 6.8, NaSG has a significant impact after exposure to high and low humidity, as well as its interaction with LAC and MCC. In the dissolution medium pH 1.2, under conditions of high humidity, the content of MgST and NaSG and their interaction show a significant influence. The release rate of LMT was affected by humidity as well as type of excipients and their interactions.

Valorization of wheat milling by-products into bacterial nanocellulose via ex-situ modification following circular economy principles

This study investigated the production of bacterial cellulose (BC) from wheat milling by-products and its post-modification to obtain nanostructures (BCNs). Crude enzyme consortia produced by Aspergillus awamori were involved in the enzymatic hydrolysis of wheat milling by-products to produce a nutrient-rich fermentation feedstock for BC production. The fermentation efficiency with Komagataeibacter sucrofermentans DSM 15973 was evaluated under various pH values and C/free amino nitrogen (FAN) ratios. The highest BC concentration (5.2 g/L) and productivity (0.74 g/L/day) were obtained at a pH value of 5.2 and a C/FAN ratio of 14.5 g/g. Sequential ex-situ modification of BC using H2SO4-assisted hydrolysis, led to BCNs with 45.8–73.1 nm fiber diameter (D) and length (L)/D ratio higher than 13. The crystallinity index (CrI) of BCNs was increased by 1.1 folds (90.1%), while thermogravimetric analysis revealed slight differences regarding the maximum decomposition temperature compared to the untreated BC (338 °C). The FT-IR spectra of BC and BCNs showed typical cellulose vibration bands while peaks at 748 cm−1 and 709 cm−1 indicated the presence of Iα and Iβ allomorphs. Size distribution of BCNs via dynamic light scattering exhibited polydispersity within the nanoscale (72 nm and 931 nm). Surface charge of BCNs (in absolute value) was increased by 44.5% compared to BC.

Preparation and characterization of carbon material with cellulose types as an additive in aqueous media

Cellulose has inspired great interest due to its unique nanostructure, elasticity, strong hydrogen bonding, and excellent improving durability for structure in compounds with other materials in the research over recent years. In this study, we investigated the effect of added cellulose as materials on carbon nanotubes (CNTs) which is limited by Van der Waals' force between bundles of tubes in aqueous media. Cellulose nanofibers (CNFs) produced from red algae show improved hydrophilic properties that –OH bundles were increased than cellulose nanocrystals (CNCs) in carbon nanotube (CNT) fluids. Due to the effect of the cellulose material introduced into CNTs, after result indicated improving properties at dispersion and electrical conductivity sides better than CNT particles alone. On the other hand, the thermal conductivity indicated a higher value CNT alone type. In the contact angle measurement, it can be confirmed that the size of the contant angle is decreased as the addition of cellulose types relieved the tangle between CNT bundles by the –OH surface and according to the change to hydrophilic. The composite with nanocellulose enables better properties of CNTs to be expressed. Thus, cellulose materials can enhance the limited properties of CNT dispersion in ease and eco-friendly aspects.

Characterizations of Alpha-Cellulose and Microcrystalline Cellulose Isolated from Cocoa Pod Husk as a Potential Pharmaceutical Excipient.

Cellulose is a non-toxic, bio-degradable, and renewable biopolymer which is abundantly available in nature. The most common source of commercial microcrystalline cellulose is fibrous wood pulp. Cellulose and its derivatives have found wide commercial applications in the pharmaceutical, cosmetic, food, paper, textile, and engineering industries. This study aims to isolate and characterize cellulose forms from cocoa pod husk (CPH) and to assess its mechanical and disintegration properties as a direct compression excipient in metronidazole tablets. Two isolated cellulose types (i.e., cocoa alpha-cellulose (CAC) and cocoa microcrystalline cellulose (C-MCC)) were compared with avicel (AV). CAC and C-MCC were characterized for their physicochemical properties using Scanning Electron Microscopy (SEM), FTIR spectroscopy, Differential Scanning Calorimetry (DSC), and X-Ray Powder Diffraction (XRD). Metronidazole tablets were produced by direct compression with cellulose. The mechanical and disintegration properties of the tablets were evaluated. CAC and C-MCC yield was 42.3% w/w and 38.25% w/w, respectively. Particle diameters were significantly different with CAC (282.22 μm) > C-MCC (161.32 μm) > AV (72.51 μm). CAC and C-MCC had a better flow than AV. SEM revealed the fibrous nature of the cellulose. FTIR and XRD analysis confirmed the presence of cellulose with crystallinity index of 69.26%, 43.83%, and 26.32% for AV, C-MCC, and CAC, respectively. C-MCC and AV are more crystalline and thermally stable at high temperatures compared to CAC. The mechanical and disintegration properties of C-MCC and AV tablets complied with pharmacopeia specifications. Taken together, C-MCC isolated from CPH displayed some fundamental characteristics suitable for use as a pharmaceutical excipient and displayed better properties compared to that of AV.

Hydrochlorothiazide/Losartan Potassium Tablet Prepared by Direct Compression.

Hydrochlorothiazide (HCTZ)/losartan potassium (LOS-K) was used as a model drug to prepare compound tablets through the investigation of the compression and mechanical properties of mixed powders to determine the formulation and preparation factors, followed by D-optimal mixture experimental design to optimize the final parameters. The type and amount of lactose monohydrate (SuperTab®14SD, 19.53–26.91%), microcrystalline cellulose (MCC PH102, 32.86–43.31%), pre-gelatinized starch (Starch-1500, 10.96–15.91%), and magnesium stearate (0.7%) were determined according to the compressive work, stress relaxation curves, and Py value. Then, the compression mechanism of the mixed powder was investigated by the Kawakita equation, Shapiro equation, and Heckel analysis, and the mixed powder was classified as a Class-II powder. The compaction pressure (150–300 MPa) and tableting speed (1200–2400 Tab/h) were recommended. A D-optimal mixture experimental design was utilized to select the optimal formulation (No 1, 26.027% lactose monohydrate, 32.811% MCC PH102, and 15.462% pregelatinized starch) according to the drug dissolution rate, using Hyzaar® tablets as a control. Following oral administration in beagle dogs, there were no significant differences in bioavailability between the No. 1 tablet and the Hyzaar® tablet in HCTZ, losartan carboxylic acid (E-3174), and LOS-K (F < F0.05). Thus, formulation and preparation factors were determined according to the combination of the compression and mechanical properties of the mixed powder and quality of tablets, which was demonstrated to be a feasible method in direct powder compression.

Technological limitations in obtaining and using cellulose biocomposites.

Among the many possible types of polymer composite materials, the most important are nanocomposites and biocomposites, which have received tremendous attention in recent years due to their unique properties. The fundamental benefits of using biocomposites as alternative materials to “petroleum-based” products are certainly shaping current development trends and setting directions for future research and applications of polymer composites. A dynamic growth of the production and sale of biocomposites is observed in the global market, which results not only from the growing interest and demand for this type of materials, but also due to the fact that for the developed and modified, thus improved materials, the area of their application is constantly expanding. Already today, polymer composites with plant raw materials are used in various sectors of the economy. In particular, this concerns the automotive and construction industries, as well as widely understood packaging. Bacterial cellulose, for example, also known as bionanocellulose, as a natural polymer with specific and unique properties, has been used extensively,primarily in numerous medical applications. Intensive research is also being carried out into composites with natural fibres composed mainly of organic compounds such as cellulose, hemicellulose and lignin. However, three aspects seem to be associated with the popularisation of biopolymers: performance, processing and cost. This article provides a brief overview of the topic under discussion. What can be the technological limitations considering the methods of obtaining polymer composites with the use of plant filler and the influence on their properties? What properties of cellulose constitute an important issue from the point of view of its applicability in polymers, in the context of compatibility with the polymer matrix and processability? What can be the ways of changing these properties through modifications, which may be crucial from the point of view of the development directions of biopolymers and bioplastics, whose further new applications will be related, among others, to the enhancement of properties? There still seems to be considerable potential to improve the cellulose material composites being produced, as well as to improve the efficiency of their manufacturing. Nevertheless, the material still needs to be well optimized before it can replace conventional materials at the industrial level in the near future. Typically, various studies discuss their comparison in terms of production, properties and highly demanding applications of plant or bacterial nanocellulose. Usually, aspects of each are described separately in the literature. In the present review, several important data are gathered in one place, providing a basis for comparing the types of cellulose described. On the one hand, this comparison aims to demonstrate the advantage of bacterial cellulose over plant cellulose, due to environmental protection and its unique properties. On the other hand, it aims to prepare a more comprehensive point of view that can objectively help in deciding which cellulosic raw material may be more suitable for a particular purpose, bacterial cellulose or plant cellulose.

Surface display of enzyme complex on Corynebacterium glutamicum as a whole cell biocatalyst and its consolidated bioprocessing using fungal-pretreated lignocellulosic biomass

A novel whole cell biocatalyst using fungal-pretreated lignocellulosic biomass was developed by displaying the enzyme complex consisting of N-acetylglucosaminidase (cNAG) and endoglucanse E (cCelE) on Corynebacterium glutamicum, hereafter called mNC. mNC showed a maximum 4.43-fold cNAG and 2.40-fold cCelE activity compared to single enzyme-secreting C. glutamicum. mNC also showed the highest efficiency of sugar production in various types of cellulose and fungal-pretreated biomass. The growth of mNC was 5.06-fold higher than that of the control. Then, the ability of mNC to produce a valuable chemical was confirmed. mNC overexpressing isopropanol biosynthesis genes showed a maximum titer of 218.9 ± 11.73 mg/L isopropanol and maintained high efficiency for isopropanol production in the recycling test, which was 90.07 ± 4.12 % during 4 cycles. This strategy can be applied to the direct saccharification of fungal-pretreated lignocellulosic biomass efficiently leading to the production of valuable products in various industrial fields.