Antibacterial and Antifungal Activity of Functionalized Cotton Fabric with Nanocomposite Based on Silver Nanoparticles and Carboxymethyl Chitosan

Organoclay-assisted disperse dyeing of polypropylene nanocomposite fabrics in supercritical carbon dioxide

Dyeing using supercritical carbon dioxide (SC-CO2) is carried out on the polypropylene (PP) nanocomposite fabrics with model disperse dye compared with their regular fabric at various dyeing temperatures and pressures. The results are compared with those obtained in aqueous dyeing method. The PP nanocompsite fabrics dyed in SC-CO2 medium exhibited higher colour strength (K/S) values compared with their PP regular fabric. The PP nanocompsite fabrics and their regular fabric dyed in SC-CO2 medium have higher K/S values than those dyed in aqueous medium. The color coordinates of all PP fabrics dyed in SC-CO2 and aqueous medium were positive with respect to a* and b* coordinates depending on the disperse red dye uptake. The PP nanocomposite fabrics dyed in SC-CO2 and aqueous medium exhibited higher antibacterial properties than their regular fabrics. All PP fabrics dyed in SC-CO2 and aqueous medium present very good washing, perspiration and light fastness.

The Influence of Titanium Dioxide (TiO2) Particle Size and Crystalline Form on the Microstructure and UV Protection Factor of Polyester Substrates

The inclusion of particles in a polymeric substrate to achieve certain properties is a well-known practice. In the case of textile substrates, this practice may deeply affect the structure of the produced yarns, as even a filament with no textile applications can be obtained. In this manuscript, titanium dioxide (TiO2) particles were incorporated into polyester (PET) chips and the influence of these fillers on the properties of yarn and fabric, and the ultraviolet protection factor (UPF) was assessed. For this purpose, rutile and anatase crystalline forms of TiO2, as well as the size of the particles, were evaluated. Moreover, parameters such as mechanical properties, orientation of the macromolecules and thermal behavior were analyzed to ensure that the textile grade is maintained throughout the production process. The results showed that the inclusion of micro- and nanoparticles of TiO2 decreases the molecular weight and tenacity of PET. Also, although orientation and crystallinity varied during the textile process, the resulting heatset fabrics did not present important differences in those parameters. Finally, the attainment of textile-grade PET-TiO2 fabrics with UPF indexes of 50+ with both rutile and anatase and micro- and nano-sized TiO2 forms was demonstrated.

Oxidized of chitosan with different molecular weights for potential antifungal and plant growth regulator applications

The application of Chitosan (CS) in drug delivery systems, plant growth promotion, antibacterial potentiality and plant defense is significantly limited by its inability to dissolve in neutral solutions. In this work, CS with different molecular weights (Mw) has been oxidized, yielding five kinds of oxidized chitosan (OCS 1-5) with solubilities in neutral solutions. The results obtained from Fourier Transform Infrared Spectroscopy clearly showed the successful oxidation of the hydroxyl group to form aldehyde and carboxyl groups. And the CS derivatives showed the wrinkled and lamellar structures on the surface of OCS. The results of antifungal activity against Fusarium graminearum showed that the OCS dissolved in 2 % (V/V) acetic acid exhibited better performance of almost complete inhibition of mycelial growth compared with CS at the concentration of 500 μg/mL. Among the five OCS, OCS-4 exhibited the best antifungal effect and had the lowest EC50 value of 581.68 μg/mL in samples. OCS-4 displayed superior promoting effect on seed germination with a germination potential of 62.2 % at a concentration of 3 g/L and a germination rate of 74.5 %. Additionally, the other four OCS also showed excellent antifungal activity with dose-dependent manners. These results indicated that the OCS had excellent antifungal potential in agricultural production.

Plackett-Burman design in the biosynthesis of silver nanoparticles with Mutisia acuminatta (Chinchircoma) and preliminary evaluation of its antibacterial activity

Background: The aim of this study was to synthesize silver nanoparticles (AgNPs) using the methanolic fraction of Mutisia acuminatta leaves using Plackett-Burman design to optimize process parameters and to evaluate its antibacterial effect. Methods: For the separation of Mutisia acuminatta phytoconstituents, chromatographic techniques were used. For characterization and identification, UV - VIS spectrophotometry, FTIR spectrophotometry, Dynamic Light Scattering (DLS) and transmission electron microscopy (TEM) were used. The Plackett-Burman design used polynomial regression statistical analysis to determine the most influential variables. Results: UV-VIS spectroscopy reported an absorbance concerning surface plasmon resonance between 410-420 nm wavelength for the AgNPs. FTIR spectrophotometry reported characteristic peaks in the biosynthesized AgNPs, observing the disappearance of spectral peaks between 1000-1500 cm -1. By UHPLC-MS, caffeic acid derivatives, coumarins, flavonoids, lignans, disaccharide and a complex formed between silver and the solvent (AgCH3CN+) were identified. Using DLS, the AgNPs presented an average hydrodynamic size of 45.91 nm. TEM determined the spherical shape of the AgNPs, presenting diameters in the range of 30 to 60 nm. The biosynthesized AgNPs showed higher antibacterial activity against Escherichia coli and Staphylococcus aureus than the total extract, the methanolic fraction and pure methanol. The polynomial model in the biosynthesis was validated with an adequate fitting representing the experimental data of the process. The most significant variables for the model obtained were the reaction pH (X 2) and the concentration of the precursor salt AgNO 3 (X 6). Conclusions: The synthesized AgNPs offer a viable option for further development due to the presence of bioactive compounds, adequate characterization and antibacterial activity.

An evaluation of antibacterial properties and cytotoxicity of UV-curable biocompatible films containing hydroxyethyl cellulose and silver nanoparticles

The present study aimed to develop biocompatible film materials with antibacterial and anticancer properties that can be cured with UV rays depending on the thiol-en click reaction mechanism. The synthesized m-Ag NPs were added to formulations containing acrylate functionality HEC, pentaerythritol tetrarkis(3-mercaptopropionate), and photoinitiator at different rates (0, 20, 40, and 60 parts per hundred (phr)). The antibacterial activity of the films was evaluated against S. aureus, P. aeruginosa and E. coli by the disk diffusion test. The antibacterial effect of the films did not form an inhibition zone for the control formulation (CmAg0) against bacteria whereas the antibacterial property increased as the Ag NPs content increased in formulations containing m-Ag NPs. The strongest resistance film against the three bacterial species was observed in the CmAg60 formulation with 60 phr silver content, and the inhibition zones for S. aureus, P. aeruginosa, and E. coli were measured as 16.5 ± 0.7, 16.5 ± 2.1, and 16 ± 1.4, respectively. The cytotoxicity of the films against healthy cells and breast cancer cell (MCF-7) lines was investigated with MTT, and it was observed that all films did not cause any inhibition in the structure of the living cell but killed the cells at a high rate in the MCF-7 line. It was mainly observed that the CmAg60 formulation showed 95.576 % cell inhibition against MCF-7. According to these results, it has been predicted that the prepared films will play a vital role in the next generation of cancer treatments.

Antimicrobial Properties of Plant Fibers

Healthcare-associated infections (HAI), or nosocomial infections, are a global health and economic problem in developed and developing countries, particularly for immunocompromised patients in their intensive care units (ICUs) and surgical site hospital areas. Recurrent pathogens in HAIs prevail over antibiotic-resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. For this reason, natural antibacterial mechanisms are a viable alternative for HAI treatment. Natural fibers can inhibit bacterial growth, which can be considered a great advantage in these applications. Moreover, these fibers have been reported to be biocompatible and biodegradable, essential features for biomedical materials to avoid complications due to infections and significant immune responses. Consequently, tissue engineering, medical textiles, orthopedics, and dental implants, as well as cosmetics, are fields currently expanding the use of plant fibers. In this review, we will discuss the source of natural fibers with antimicrobial properties, antimicrobial mechanisms, and their biomedical applications.

Chitosan Nanoparticles as Bioactive Vehicles for Textile Dyeing: A Proof of Concept

In recent years bioactive textiles have risen to the forefront of consumers perception due to their potential protection against virus, fungi and bacteria. However, traditional textile staining is an eco-damaging process that and current methods of textile functionalization are expensive, complicated and with great environmental impact. With that in mind, this work sought to show a possible solution for this problematic through the usage of a novel one step textile dyeing and functionalization method based upon nanoencapsulated textile dyes (NTDs). To do so navy blue everzol NTDs were produced with chitosan, cotton dyed, characterized through FTIR and SEM and biological potential evaluated through biocompatibility screening and antimicrobial activity against skin pathogens. The data obtained showed that NTDs effectively dyed the target textile through a coating of the cotton fibre and that NTDs formed hydrogen bonds with the cellulose fibre via electrostatic interactions of the chitosan amino groups with cotton sulphate groups. From a biocompatibility perspective NTDs dyed cotton had no deleterious effects upon a skin cell line, as it promoted cellular metabolism of HaCat cells, while traditionally died cotton reduced it by 10%. Last but not least, NTDs dyed cotton showed significant antimicrobial activity as it reduced viable counts of MRSA, MSSA and A. baumannii between 1 and 2 log of CFU while traditional dyed cotton had no antimicrobial activity. Considering these results the novel method proposed shows is a viable and ecological alternative for the development of antimicrobial textiles with potential biomedical applications.

Sustainable-Green Synthesis of Silver Nanoparticles Using Aqueous Hyssopus officinalis and Calendula officinalis Extracts and Their Antioxidant and Antibacterial Activities

Silver nanoparticles (AgNPs) biosynthesized using aqueous medical plant extracts as reducing and capping agents show multiple applicability for bacterial problems. The aim of this study was to expand the boundaries on AgNPs using a novel, low-toxicity, and cost-effective alternative and green approach to the biosynthesis of metallic NPs using Calendula officinalis (Calendula) and Hyssopus officinalis (Hyssopus) aqueous extracts. The formation of AgNPs was confirmed by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) techniques. The effectiveness of biosynthesized AgNPs in quenching free radicals and inhibiting the growth of Gram-positive and Gram-negative microorganisms was supported by in vitro antioxidant activity assay methods and using the Kirby-Bauer disk diffusion susceptibility test, respectively. The elucidated antimicrobial and antioxidative activities of medical plant extracts were compared with data from the engineered biosynthetic AgNPs. The antimicrobial effect of engineered AgNPs against selected test cultures was found to be substantially stronger than for plant extracts used for their synthesis. The analysis of AgNPs by TEM revealed the presence of spherical-shaped nano-objects. The size distribution of AgNPs was found to be plant-type-dependent. The smaller AgNPs were obtained with Hyssopus extract (with a size range of 16.8 ± 5.8 nm compared to 35.7 ± 4.8 nm from Calendula AgNPs). The AgNPs' presumably inherited biological functions of Hyssopus and Calendula medical plants can provide a platform to combat pathogenic bacteria in the era of multi-drug resistance.

Recent Advances in Functionalization of Cotton Fabrics with Nanotechnology

Nowadays, consumers understand that upgrading their traditional clothing can improve their lives. In a garment fabric, comfort and functional properties are the most important features that a wearer looks for. A variety of textile technologies are being developed to meet the needs of customers. In recent years, nanotechnology has become one of the most important areas of research. Nanotechnology’s unique and useful characteristics have led to its rapid expansion in the textile industry. In the production of high-performance textiles, various finishing, coating, and manufacturing techniques are used to produce fibers or fabrics with nano sized (10⁻⁹) particles. Humans have been utilizing cotton for thousands of years, and it accounts for around 34% of all fiber production worldwide. The clothing industry, home textile industry, and healthcare industry all use it extensively. Nanotechnology can enhance cotton fabrics’ properties, including antibacterial activity, self-cleaning, UV protection, etc. Research in the field of the functionalization of nanotechnology and their integration into cotton fabrics is presented in the present study.

Bibliometric Analysis of Current Status of Circular Economy during 2012–2021: Case of Foods

Food is usually recognized as a limited resource in sustainability, recognized by the United Nations (UN) Sustainable Development Goal (SDG) 2, which aims to achieve zero hunger. It is expected that the circular economy (CE) can improve processes related to food production. The objective of the present study was to apply a bibliometric approach using VOSviewer visualization software as a research tool to analyze the relevant literature from the Scopus database in the field of circular economy and its relation to improvements in food issues throughout 2012–2021. A total of 1316 articles were analyzed. Italy was the most productive country with 313 articles, with Wageningen University & Research the organization with the most publications with 39 articles. The top 10 institutions originated from Italy, The Netherlands, France, and Denmark. Sustainability was the most productive journal with 107 articles. Bioresource Technology had the highest average citation frequency (44.68). The study helps initiate investigations to adapt the results obtained and create new strategies for increasing food circular economy efforts.

Optimization of Synthesis of Silver Nanoparticles Conjugated with Lepechinia meyenii (Salvia) Using Plackett-Burman Design and Response Surface Methodology—Preliminary Antibacterial Activity

In the present investigation, an ethanolic fraction (EF) of Lepechinia meyenii (salvia) was prepared and fractionated by gradient column chromatography, and the main secondary metabolites present in the EF were identified by HPLC-MS. Silver nanoparticles (AgNPs) were synthesized and conjugated with the EF of Lepechinia meyenii (salvia). The AgNPs synthesis was optimized using Plackett-Burman design and response surface methodology (RSM), considering the following independent variables: stirring speed, synthesis pH, synthesis time, synthesis temperature and EF volume. The AgNPs synthesized under the optimized conditions were characterized by UV visible spectroscopy (UV-VIS), Fourier Transform Infrared Spectroscopy (FT-IR), Dynamic Light Scattering (DLS) and Scanning Transmission Electron Microscopy (STEM). The antibacterial activity of the AgNPs against Staphylococcus aureus (ATCC® 25923) was evaluated. The following flavonoids were identified: rosmarinic acid, diosmin and hesperetin-7-O-rutinoside. The optimized conditions for the synthesis of nanoparticles were pH 9.45, temperature 49.8 °C, volume of ethanolic fraction 152.6 µL and a reaction time of 213.2 min. The obtained AgNPs exhibited an average size of 43.71 nm and a resonance plasmon of 410–420 nm. Using FT-IR spectroscopy, the disappearance of the peaks between 626.50 and 1379.54 cm−1 was evident with the AgNPs, which would indicate the participation of these functional groups in the synthesis and protection of the nanoparticles. A hydrodynamic size of 47.6 nm was obtained by DLS, while a size of 40–60 nm was determined by STEM. The synthesized AgNPs conjugated with the EF showed a higher antibacterial activity than the EF alone. These results demonstrate that the AgNPs synthesized under optimized conditions conjugated with the EF of the Lepechinia meyenii (salvia) presented an increased antibacterial activity.

Progress in Research of Chitosan Chemical Modification Technologies and Their Applications

Chitosan, which is derived from chitin, is the only known natural alkaline cationic polymer. Chitosan is a biological material that can significantly improve the living standard of the country. It has excellent properties such as good biodegradability, biocompatibility, and cell affinity, and has excellent biological activities such as antibacterial, antioxidant, and hemostasis. In recent years, the demand has increased significantly in many fields and has huge application potential. Due to the poor water solubility of chitosan, its wide application is limited. However, chemical modification of the chitosan matrix structure can improve its solubility and biological activity, thereby expanding its application range. The review covers the period from 1996 to 2022 and was elaborated by searching Google Scholar, PubMed, Elsevier, ACS publications, MDPI, Web of Science, Springer, and other databases. The various chemical modification methods of chitosan and its main activities and application research progress were reviewed. In general, the modification of chitosan and the application of its derivatives have had great progress, such as various reactions, optimization of conditions, new synthetic routes, and synthesis of various novel multifunctional chitosan derivatives. The chemical properties of modified chitosan are usually better than those of unmodified chitosan, so chitosan derivatives have been widely used and have more promising prospects. This paper aims to explore the latest progress in chitosan chemical modification technologies and analyze the application of chitosan and its derivatives in various fields, including pharmaceuticals and textiles, thus providing a basis for further development and utilization of chitosan.

Green Synthesis of a Novel Silver Nanoparticle Conjugated with Thelypteris glandulosolanosa (Raqui-Raqui): Preliminary Characterization and Anticancer Activity

In the last decade, the green synthesis of nanoparticles has had a prominent role in scientific research for industrial and biomedical applications. In this current study, silver nitrate (AgNO3) was reduced and stabilized with an aqueous extract of Thelypteris glandulosolanosa (Raqui-raqui), forming silver nanoparticles (AgNPs-RR). UV-vis spectrophotometry, dynamic light scattering (DLS), and scanning transmission electron microscopy (STEM) were utilized to analyze the structures of AgNPs-RR. The results from this analysis showed a characteristic peak at 420 nm and a mean hydrodynamic size equal to 39.16 nm, while the STEM revealed a size distribution of 6.64–51.00 nm with an average diameter of 31.45 nm. Cellular cytotoxicity assays using MCF-7 (ATCC® HTB-22™, mammary gland breast), A549 (ATCC® CCL-185, lung epithelial carcinoma), and L929 (ATCC® CCL-1, subcutaneous connective tissue of Mus musculus) demonstrated over 42.70% of MCF-7, 59.24% of A549, and 8.80% of L929 cells had cell death after 48 h showing that this nanoparticle is more selective to disrupt neoplastic than non-cancerous cells and may be further developed into an effective strategy for breast and lung cancer treatment. These results demonstrate that the nanoparticle surfaces developed are complex, have lower contact angles, and have excellent scratch and wear resistance.

Physical and Mechanical Characterization of a Functionalized Cotton Fabric with Nanocomposite Based on Silver Nanoparticles and Carboxymethyl Chitosan Using Green Chemistry

Cotton is the most widely used natural fiber for textiles but its innate capacity to absorb moisture, retain oxygen, and high specific surface area make it more prone to microbial contamination, becoming an appropriate medium for the growth of bacteria and fungi. In recent years, the incorporation of silver nanoparticles in textile products has been widely used due to their broad-spectrum antibacterial activity and low toxicity towards mammalian cells. The aim of the current study is to synthesize and characterize a nanocomposite based on silver nanoparticles and carboxymethyl chitosan (AgNPs-CMC), which was utilized to provide a functional finish to cotton fabric. The scanning electron microscope (SEM) to produce a scanning transmission electron microscope (STEM) image showed that the nanocomposite presents AgNPs with a 5–20 nm size. The X-ray diffraction (XRD) analysis confirmed the presence of silver nanoparticles. The concentration of silver in the functionalized fabric was evaluated by inductively coupled plasma optical emission spectrometry (ICP-OES), which reported an average concentration of 13.5 mg of silver per kg of functionalized fabric. SEM showed that silver nanoparticles present a uniform distribution on the surface of the functionalized cotton fabric fibers. On the other hand, by infrared spectroscopy, it was observed that the functionalized fabric variation (compared to control) had a displaced peak of intensity at 1594.32 cm−1, corresponding to carboxylate anions. Similarly, Raman spectroscopy showed an intense peak at 1592.84 cm−1, which corresponds to the primary amino group of carboxymethyl chitosan, and a peak at 1371.5 cm−1 corresponding to the carboxylic anions. Finally, the physical and mechanical tests of tensile strength and color index of the functional fabric reported that it was no different (p ˃ 0.05) than the control fabric. Our results demonstrate that we have obtained an improved functionalized cotton fabric using green chemistry that does not alter intrinsic properties of the fabric and has the potential to be utilized in the manufacturing of hospital garments.