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Chitosan is a natural polymer, which has similar structure and bioactivity with glycosaminoglycan, and is a potential material for use as injectable hydrogels. Authors elucidate structure-property relationship with particular focus on chitosan-based injectable hydrogels, and their application as biomaterials. The different gelation approach, including physical cross-link, chemical cross-link, ionic cross-link and supramolecular interaction, enable a variety of chitosan-based injectable hydrogels to be formed. These gelation methods have significant impact on the structure and properties of hydrogels, which governs their use as tissue engineering scaffold and drug delivery vehicle. [ABSTRACT FROM AUTHOR]

Decontamination of airliner cabins may be required, for example, in the event of an epidemic or pandemic. To be performed safely, decontamination must be compatible with aircraft materials and systems. This paper examines the suitability, with respect to cabin textiles, of vapour phase hydrogen peroxide for airliner decontamination applications. The effect of vapour phase and liquid hydrogen peroxide on common airliner interior textile materials, namely wool, nylon, polyester, and Nomex, has been studied by examining the physical and chemical changes and the resulting effect on mechanical properties caused by decontamination. The physical changes induced by the sorption of moisture had an effect on the mechanical properties of all of the materials examined. However, only wool attacked chemically by hydrogen peroxide experience a significant effect on its mechanical properties. [ABSTRACT FROM AUTHOR]

A pressure-washing system was developed and assessed for the removal of residual dyes and washing of fabrics. The system was comprised of an acrylic water-tank, ultra-high molecular weight polyethylene rollers, a variable water pressure system rated at 1000 psi and a set of four linear spray nozzles with various exit divergence angles. To further decrease the water consumption, heated aerated impinging jets were added to the setup. Two cameras and 3D image processing algorithms were used to monitor fabric deformation during the washing process. Results show that increasing the water pressure up to 150 psi reduced the amount of water needed and did not cause fabric distortion. A small inclination angle of 20 degrees in the direction opposite to the flow of the fabric added some efficiency to the washing process. Although temperature alone did not exhibit a strong impact on efficiency, aerated-jet experiments under a water pressure of 100 psi at 60°C showed an increase of washing efficiency over non-aerated jets. [ABSTRACT FROM AUTHOR]

Hemp fabric is hydrolyzed with cellulase, hemicellulase/cellulase, and cellulase plus additional β-glucosidase. The effect of the admixture of hemicellulase and β-glucosi dase is evaluated in terms of hydrolysis rate and product properties. The influence of mechanical action during the treatment is also taken into account. Treated samples are characterized by weight loss per incubation time, tensile strength, crystallinity, acces sibility, and pore structure. The admixture of hemicellulase and,β-glucosidase produces only minor effects without mechanical action on the hydrolysis rate, but mechanical action applied during the treatment dramatically increases weight loss. While crystal linity changes upon hydrolysis are insignificant, the pore structure is strongly influenced by the choice of enzyme system. Hemicellulase seems to promote the formation of smaller pores, while cellobiase forms larger pores. [ABSTRACT FROM PUBLISHER]

Three different scouring methods are applied to open-end and ring spun yarns prior to hydrogen peroxide bleaching with and without metal ions present. The scouring procedures include a penetrating treatment with aqueous sodium hydroxide solution, a nonswelling solvent extraction, and a fiber surface-affecting treatment with pectinase enzymes. Properties of the treated yarns and fiber damage are studied after each process step. Conventional scouring with sodium hydroxide followed by peroxide bleaching causes the highest deterioration on the molecular level, but results in a high level of whiteness, Solvent extracted yams exhibit superior tensile strength, which is preserved more or less unchanged throughout any subsequent treatment. The bioscouring process with enzymes renders the yams strikingly soft. The effects are generally more pro nounced for open-end spun yams, suggesting that differences in yarn structure may have an impact on the effectiveness of scouring. [ABSTRACT FROM PUBLISHER]

Cotton, linen, ramie, and viscose rayon fabrics along with a cotton / linen blend were hydrolyzed with cellulase from Trichoderma viride. Surface fibrils were eliminated by a 6 hour treatment in all cases. The loss of fibrillar matter appeared to be the primary cause of weight loss at this stage. On prolonged treatment, cotton, linen, and viscose rayon lost weight at a faster rate than ramie and the cotton / linen blend. The fall in yam strength was progressive with increasing weight loss for cotton and viscose, while for linen and ramie it was slight initially and then increased sharply. Retention of strength after 48 hours' incubation time increased in the order viscose rayon << cotton < ramie < linen, whereas weight loss increased in the order ramie < linen < cotton < viscose rayon. X-ray crystallinity and moisture sorption of the samples did not change after the treatment, indicating that the mechanism of endwise attack of the cellulase at accessiblc cellulose chains on crystallite surfaces appeared to apply to all four fibers. The location of enzymatic attack could be monitored with a light microscope using Congo red staining in the case of cotton and linen, but not ramie or rayon. Changes in surface morphology could be followed for all the enzyme-treated fibers by scanning electron microscopy. Additionally, mechanical tests demonstrated the changes in stretchability and stiffness of the fabrics and the mobility of yams within the samples. [ABSTRACT FROM PUBLISHER]

Relations were studied between fiber structure and mechanical properties of cotton fibers crosslinked with 1,2,3,4 butanetetracarboxylic acid (BTCA). BTCA was either applied directly to the fibers (NPT) or after they had received a swelling treatment with caustic soda (MER), liquid ammonia (LAT), or monomethylamine (MMA). In some instances BTCA was applied before the caustic treated fibers had been dried (NDMER). The water retention value (WRV) of MER fibers was markedly higher than that of NPT, LAT, or MMA fibers. After BTCA treatment, however, the WRV of MER fibers fell sharply, but that of MMA or LAT samples did not. Thus the WRV s of BTCA MER and NDMER fibers approached those of MMA and LAT products. The breaking force of BTCA fibers approached the same value at high BTCA contents, with or without mercerization or methylamine preswelling. It appeared that LAT cotton might retain greater strength than the other samples at high BTCA contents. The breaking extensions of BTCA fibers that had received a preswelling treatment were higher than those of fibers that had not been pretreated. Properties of MER and NDMER BTCA fibers were similar, even though it appeared that the BTCA was more uniformly distributed in the NDMER fibers. The breaking twist angle ( BTA ) was determined as a measure of brit tleness ; the BTA relation with extension for the BTCA samples was similar to a previously determined relation for cotton treated with dimethyloldihydroxyethyleneurea. [ABSTRACT FROM PUBLISHER]

The breaking stress (BS), breaking extension (BE), initial modulus (IM), torsional modulus (TM) and breaking twist angle (BTA) of a wide range of fibers were determined. The fibers included high performance and industrial fibers whose BTA values had not been determined previously. BTA, as a measure of brittleness, evaluates fiber properties under shear rather than tensile stress and the relationships between BTA and BE and also IM were developed. IM/TM is a measure of the lengthwise to lateral cohesiveness of a fiber and is shown to correlate highly with breaking stress. The effects of chemical and fine structure on the measured mechanical properties of the fibers are discussed. [ABSTRACT FROM AUTHOR]

Innovations in food biotechnology reflect the increasing demand for healthy food and the change in conventional dietary patterns to plant-based diets, encouraging the development of functional products and opening new perspectives for industry interests. In addition, the development of vegetable-based products is supported by several studies that state that plant-based diets help reduce the risk of diseases, reduce stress, and even help maintain healthy body weight, making this diet a promising development for the future. The industry mainly uses fermentation techniques to obtain plant-based foodstuffs. However, fermentation is just one method that can develop probiotic products. Other methods include high moisture extrusion cooking and applying shear cells, for instance, for developing vegetable meats. This article summarizes trends and shifts in eating preferences, the response of the respective industry, and the future potential of plant-based products., Competing Interests: The authors declare no conflict of interest., (© 2022 The Author(s).)

Polyphenolic compounds have many benefits, one of which being their efficacy as antioxidants. They can be extracted from various parts of plants and from agricultural waste. In this research, sugarcane pulp, and empty palm fruit bunches from the palm oil production were investigated as potential raw materials. This study aims to determine solvents and easy-to-perform extraction methods that show the highest effectivity in regards to total phenolic and flavonoid yield and the correlated antioxidant activity. Extraction methods comprised maceration, Soxhlet extraction, and ultrasound assisted extraction (UAE); solvents that were investigated included water, 70% methanol and 70% ethanol. The antioxidant activity was measured by the DPPH (diphenyl-2-picrylhydrazyl) method and FRAP (Ferric Reduction Ability of Plasma) method. Based on the amount of polyphenol compounds as well as the antioxidant activity, the experiments showed that Soxhlet extraction with 70% methanol as solvent worked best for palm bunch waste and sugar cane pulp, resulted in about two times higher values for total phenolic content, flavonoid content and FRAP antioxidant activity as well as extract mass (yield) compared to the results from other extraction methods or solvents used in this experiment. The antioxidant activity of the extracts as measured by DPPH method seemed also to be promising, although the trend among solvent and extraction method was rather inconclusive., Competing Interests: The authors declare no conflict of interest., (© 2022 The Author(s).)

Substantial amounts of industrial, agricultural, medical and domestic water worldwide are polluted by different types of contaminants. Removing these contaminants from effluent by adsorbent materials made from abundant, inexpensive polysaccharides is a feasible and promising approach to deal with this problem. In the present study, pectin blended with four other types of anionic polysaccharides, including alginate, carrageenan, xylan and xanthan, were crosslinked with zinc acetate and formed into thin films. In addition, a negatively charged polyelectrolyte, poly(4-styrenesulfonic acid-co-maleic acid) sodium salt (PSSMA) was coated on the film surface with the goal of increasing the capture of cationic contaminants. The average film thickness was measured by a digital micrometer. Surface morphologies and element analysis were obtained by energy dispersive spectroscopy connected with scanning electron microscopy. The swelling ratio and the mechanical properties of the films were investigated in relationship to their composition and PSSMA coating. The sorption of model cationic pollutants clearly improved for coated films and showed to be predominantly based on the interaction of positively and negatively charged groups between film/coating and contaminants., (Published by Elsevier B.V.)

The goal of this study was to investigate the role of ethanol and temperature on the hydroxyl and carbonyl groups in biopolyol produced from hydrothermal liquefaction of loblolly pine (Pinus spp.) carried out at 250, 300, 350 and 390°C for 30min. Water and water/ethanol mixture (1/1, wt/wt) were used as liquefying solvent in the HTL experiments. HTL in water and water/ethanol is donated as W-HTL and W/E-HTL, respectively. It was found that 300°C and water/ethanol solvent was the optimum liquefaction temperature and solvent, yielding up to 68.1wt.% bio-oil and 2.4wt.% solid residue. (31)P-NMR analysis showed that biopolyol produced by W-HTL was rich in phenolic OH while W/E-HTL produced more aliphatic OH rich biopolyols. Moreover, biopolyols with higher hydroxyl concentration were produced by W/E-HTL. Carbonyl groups were analyzed by (19)F-NMR, which showed that ethanol reduced the concentration of carbonyl groups., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Bovine serum albumin has been PEGylated and glycosylated to create mimetic materials for the extracellular matrix (ECM) with potential tissue engineering applications. Different surfaces for cell adhesion were achieved by crosslinking the initial albumin product and forming either a coating or a sponge-like three-dimensional morphology to mimic the mesh structure of natural ECM. The biocompatibility of the albumin matrix with mammalian cells was evaluated using cell culture assays with NIH 3T3 cells. The results indicated that glycoprotein composition and specific morphology of the assembly can improve the cell growth environment. These ECM mimetic structures might eventually be considered to serve as alternatives for the more expensive collagen and elastin based ECM substances currently in use in tissue engineering., (© 2015 Wiley Periodicals, Inc.)

Crystalline poly(L-lactide) (PLLA) nanoparticles were prepared by aminolysis of electrospun PLLA nanofibers and subsequently labeled by a fluorescent colorant. The size of the nanoparticles could be controlled by either the conditions of the aminolysis reaction or the diameter of the original electrospun fiber. The latter method resulted in higher yield. Although the as-spun nanofibers were generally amorphous, the nanoparticles showed high crystallinity in the typical α-form of PLLA crystals, as revealed by X-ray diffraction and differential scanning calorimetry. Gel-permeation chromatography was used to determine the molecular weight of the formed particles in relation to aminolysis time. After aminolysis, PLLA nanoparticles spontaneously generated amine groups on the surface, which are available for further modifications. In this study the amine groups were reacted with isothiocyanate groups, and fluorescein-5'-isothiocyanate was successfully attached to the PLLA nanoparticles. Smaller particles showed significantly higher fluorescein binding density. Through this simple 'top-down' routine, it was possible to create nanoparticles with tailorable size and specific surface functions. Such materials could serve in bioimaging or nanomedicine applications.