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The purpose of this paper is to fabricate colorless cotton fabrics with good antibacterial activity and durability.

Chitosan (CS) based silver nanoparticles (AgNPs) were formed in CS solutions as the antibacterial agent. The reducing agent was sodium borohyride. The concentrations of the CS solutions ranged from 0.1 to 1 percent (w/v). Cotton fabrics were impregnated by these CS/AgNPs solutions.

All of these fabrics exhibited superior antibacterial activities. The antibacterial activity still showed great efficiency even after 81 home launderings. Moreover, the results of color change and whiteness indicated that the cotton fabrics treated by CS/AgNPs complex with higher CS concentration had less color change compared with other samples.

Fabrics treated by this method could reduce the brown color brought by AgNPs. The paper also suggests that cotton fabrics treated by AgNPs formed in a relatively higher CS concentration not only had good antibacterial activity but also were colorless.

The influence of CS ratio in CS/AgNPs complexes on the antibacterial activity and color of cotton fabrics was studied, which has been rarely reported in previous papers. The fabrics prepared by this method are promising candidates for a wide range of general applications.

The purpose of this paper is to develop non-leaching and eco-friendly antimicrobial waterborne polyacrylates with excellent antibacterial properties by grafting antibacterial vinyl monomer, glycidyl methacrylate (GMA) modified polyhexamethylene guanidine hydrochloride (PHMG).

PHMG of different molecular weights were modified by GMA to synthesize antibacterial vinyl monomer, GMA-modified PHMG (GPHMG). Different content and molecular weights of GPHMG were used to synthesize antimicrobial waterborne polyacrylates through emulsion polymerization.

The addition of GPHMG gained by modifying PHMG showed little influence on thermal stability of the films, but decreased the glass transition temperature(Tg). Meanwhile, the tensile strength decreased, while the breaking elongation increased. The antibacterial properties of the antibacterial films with different GPHMG contents were studied, when GPHMG content was around 0.9 Wt.%, antibacterial films showed excellent antibacterial activity (antibacterial rate >= 99.99 per cent). When weight content of GPHMG in the films remained constant, antibacterial property of films increased first and then decreased with the increase of molecular weight of GPHMG. The structural antibacterial polymer film had more perdurable antibacterial activity than the blended one.

The grafting efficiency of GPHMG to antimicrobial waterborne polyacrylates could be further improved.

Antimicrobial waterborne polyacrylates with excellent antibacterial properties can be used to antibacterial coating and adhesive.

The antibacterial properties of films with different molecular weight of GPHMG were studied, and the durability and stability of antibacterial properties between structural antimicrobial films and blended antimicrobial films were also investigated by ring-diffusion method.

A widespread focus on the plant-based antimicrobial cotton fabric finishes has been accomplished with notable importance in recent times. The antimicrobials prevent microbial dwelling in fabrics, which causes severe infections to the fabric users. Chemical disinfectants were conventionally used in fabrics to address this challenge; however, they were found to be toxic to humans. Thus, the present study aims to deal with the utilization of phytochemical extracts from different parts of Pongamia pinnata as antimicrobial coatings in cotton fabrics.

The root, bark and stem were collected and washed several times using tap water. Then, the leaves were dried at room temperature and the root and bark were dried using an oven at 40ºC. After drying, they were ground into fine powder and extracted with ethanol using the Soxhlet apparatus. After that the extract was coated on the fabric tested for antimicrobial studies.

The results reported that the leaf extract of P. pinnata-coated fabric exhibited enhanced antibacterial property towards gram-negative Escherichia coli bacteria, followed by root, bark and stem. The wash durability test in the extract-coated fabric samples revealed that dip-coating retained antibacterial activity until five washes. Thus, the current study clearly suggests that the leaf extract from P. pinnata is highly useful to develop antibacterial cotton fabrics as health-care textiles.

The novelty of the present work is to obtain the crude extract from the leaves, bark, root and stem of P. pinnata and evaluate their antibacterial activity against E. coli, upon being coated on cotton fibres. In addition, the extracts were subjected to wash durability analysis to study the coating efficiency of the phytochemicals in cotton fabrics and a probable mechanism for the antibacterial activity of P. pinnata extracts was also presented.

Nowadays, the usage of antibacterial textiles is very popular for different type of textiles. The silver (Ag) and zinc oxide (ZnO) are the most popular materials in order to improve antibacterial properties of textiles. The purpose of this paper is to investigate the possibility to produce Ag nanoparticle (NP), ZnO NP, Ag/ZnO NP composite materials in this experimental study.

It was investigated whether it was possible to produce Ag NP, ZnO NP, Ag/ZnO NP composite materials by hydrothermal method which was known as in-situ approach on the fiber. In addition, the colloidal silver (Ag+) was produced by electrolysis method, and used instead of process water which was necessary during generating of NPs on the fiber by this method. After whole applications, the samples were characterized by SEM, XRD, EDX analyses and the antibacterial activity of specimens was tested according to the ASTM E 2149-01 (gram-negative Escherichia coli). In addition, the resistance to the repeated washes of these antibacterial samples was investigated.

The production of NPs on the fiber was achieved. The results showed that the samples had sufficient antibacterial activity and this activity did not reduce depending on repeated washing treatments.

Because of usage of one type of fiber, it would be necessary to make researches on the different type of fiber, testing procedure (with different bacteria), washing replications and prescriptions.

During the process the temperature control is very important for the produced fiber. In addition chosen antibacterial test method is crucial for the testing of activity of product. Fiber must be washed at least once to remove unfixed NPs on the fiber.

The technical antibacterial polyester fiber was in-situ coated by hydrothermal method with Ag, ZnO, Ag/ZnO composite NPs.

The healthcare and hygiene textiles are gaining more importance for their eco-friendly and effective antimicrobial properties that have become essential to safeguard human beings from harmful microorganisms. The fabrics finished with chemical-based antimicrobial agents lead to environmental issues and are harmful to human beings. The paper aims to discuss these issues.

The present investigation is to develop a fabric with antioxidant and antimicrobial properties using the extracts of brown algae. Antimicrobial property has been imparted to the cotton fabric using microcapsules of brown seaweed extracts using the pad-dry-cure method. The presence of bioactive compounds and antioxidant activities of brown algae extracts was evaluated using gas chromatography-mass spectrometry and 2, 2-diphenyl-1-picrylhydrazyl radical scavenging technique, respectively. The total phenolic content of the seaweed extract was determined by the Folin-Ciocalteu method. The minimum bactericidal concentration and minimum inhibitory concentration methods were used to determine the antibacterial activity of the bacterial reduction percentage and parallel streak methods were used evaluate the antibacterial activity of seaweed-treated fabrics.

The methanol fraction of the treated fabric had the highest antioxidant activity (42.5+1.21 per cent), because the higher phenolic content traps the reactive oxygen species and develops the cells present in the skin. The results show that the lower inhibition (250 µg/mL) and bactericidal concentrations (1,000 µg/mL) possess higher antibacterial activity. The results also show that the treated fabric possess higher bacterial reduction of 96 per cent and higher zone of inhibition against Escherichia Coli and Staphylococcus Aureus which was about 35 mm and 40 mm. The air permeability, bending length and the wicking behaviour of the treated fabric were slightly reduced, but it has good bursting strength compared with the untreated fabric.

Such treated fabric is used for making wound dressing, surgical gowns, antibacterial socks and gauze bandage products in healthcare and hygiene textiles.

In this study, fabrication of polymer and cotton fabric exhibiting stimuli-responsive wetting and water vapor permeability features together with antibacterial activity was aimed.

Temperature and pH-responsive poly(N-isopropyl acrylamide-graft-chitosan) (PNIPAM-g-CS) copolymer were produced via the free radical addition polymerization method and fixed to the cotton fabric using butane tetracarboxylic acid (BTCA) cross-linker by double-bath impregnation method. The chemical structure of the graft copolymer was characterized by Fourier-transform infrared spectroscopy (FT-IR) spectroscopy and H-Nuclear magnetic resonance (1H NMR) analyses. Thermo-responsive behavior of the fabric was investigated by wetting time and water uptake tests, contact angle measurement and surface energy calculation. Additionally, antibacterial activity of the fabric treated with copolymer was studied against S. aureus bacterium.

PNIPAM-g-CS graft copolymer was synthesized successfully, which had lower critical solution temperature (LCST) value of 32 °C and exhibited thermo-responsive property. The treated fabrics exhibited hydrophilic character at temperatures below the LCST and hydrophobic character at temperatures above the LCST. It was found that polymer-coated fabric could have regulated the water vapor permeability by the change in its pore size and hydrophilicity depending on the temperature. Additionally, treated fabric displayed a pH-responsive water absorption behavior and strong antibacterial activity against S.aureus bacterium.

In the study, it has been shown that the cotton fabrics can be fabricated which have antibacterial activity and capable of pH and temperature responsive smart moisture/water management by application of copolymer. It is thought that the fabric structures developed in the study will be promising in the production of medical textile structures where antibacterial activity and thermophysiological comfort are important.

The purpose of this paper is to validate the antimicrobial activity (both antibacterial and antifungal) of in vivo and in vitro ethanolic anthocyanin extracts of Clitoria ternatea L. (vivid blue flower butterfly-pea) and Dioscorea alata L. (purple yam) against selected bacteria (Bacillus subtilis, Staphylococcus aureus and Escherichia coli) and fungi (Fusarium sp., Aspergillus niger and Trichoderma sp.).

The freeze-dried samples (0.2 g) from in vivo vivid blue flowers of C. ternatea L. were extracted using 10 mL ethanol (produced ethanolic red extraction) and 10 mL distilled water (produced aqueous blue extraction) separately. Two-month-old in vitro callus samples (0.2 g) were only extracted using 10 mL ethanol. The anthocyanin extractions were separated with the addition (several times) of ethyl acetate and distilled water (1:2:3) to remove stilbenoids, chlorophyll, less polar flavonoids and other non-polar compounds. Furthermore, the antimicrobial properties were determined using agar diffusion technique. Three bacteria (B. subtilis, S. aureus and E. coli) and fungi (F. sp., A. niger and T. sp.) were streaked on bacteria agar and dextrose agar, respectively, using “hockey stick”. Then, the sterile paper discs (6 mm diameter) were pipetted with 20 µL of 1,010 CFU/mL chloramphenicol (as control for antibacterial) and carbendazim (as control for antifungal) in vivo and in vitro extracts. The plates were incubated at room temperature for 48 h, and the inhibition zones were measured.

Based on the results, both in vivo and in vitro ethanolic extracts from vivid blue flowers of C. ternatea L. showed the best antibacterial activity against the same bacteria (B. subtilis), 11 and 10 mm inhibition zones, respectively. However, different antifungal activity was detected in in vitro ethanolic callus extract (12 mm), which was against T. sp., contrary to in vivo ethanolic extract (10 mm), which was against F. sp.; antibacterial activity of D. alata L. was seen against the same bacteria (E. coli) with the highest inhibition zone for in vivo extract (8.8 mm), followed by in vitro extract (7.8 mm).

Anthocyanins are responsible for the water soluble and vacuolar, pink, red, purple and blue pigments present in coloured plant pigments. These pigments (pink, red, purple and blue) are of important agronomic value in many crops and ornamental plants. However, anthocyanins are not stable and are easy to degrade and fade whenever exposed to light.

Plant extracts containing bioactive agents with antimicrobial properties have been found to be useful in treating bacterial and fungal infections, as well as showed multiple antibiotic resistance.

Both in vivo and in vitro extracts from vivid blue flower petals (C. ternatea L.) and purple yam (D. alata L.) have important applications as natural antimicrobial (antibacterial and antifungal) agents in the coating industry, instead of natural pharmaceutical products.

This study aims to synthesize some new curcumin containing Aroyl derivatives dyestuffs and study their application in dyeing polyester fabrics, rendering to their antibacterial evaluation.

Modification of curcumin dye was carried out by introducing benzoyl rings through coupling with curcumin. All newly synthesized dyes were characterized by elemental analyses and spectral data (IR, 1 H-NMR and MS). Moreover, the optimal dyeing condition was assigned. Antibacterial activities of the dyed samples at different concentrations of both dyes were studied against gram positive (Staph aureus) and gram-negative (Salmonellatyphimurium) bacteria.

Synthesized curcumin containing benzoyl dyes were applied on polyester fabrics. Meanwhile, these synthesized dyes showed reasonable results towards fastness properties at optimal conditions matching the curcumin dye. In addition to their good fastness assets, synthesized dyes displayed antibacterial efficacy towards both gram positive and gram-negative bacteria. The dyed polyester fabrics showed higher antibacterial efficacy after multiple events of washing.

The synthesized benzoyl containing curcumin moiety was not described before.

Disperse dyes derived from curcumin were prepared via coupling of various diazonium salts of p-aminobenzaldhyde, p-aminoacetopheneone, p-aminobenzoic acid and p-aminobenzoyl chloride with curcumin. The resulting disperse dyes were applied on polyester fabrics at optimal conditions, and antibacterial efficacy of dyed fabrics were evaluated.

Curcumin being was used in food colouration and was effective for dyeing and antimicrobial finishing on textile fabrics. Novel antibacterial dyestuff containing curcumin moieties with benzoyl amine coupling components showed interesting colourant for polyester fabrics. This work introduced innovative disperse dyes for medical textile applications.

This paper aims to evaluate in vitro antibacterial activity of oregano essential oil against foodborne pathogens as a starting point for the use of spice as a natural preservative in food.

Disc and well‐diffusion assays were performed to investigate antibacterial activity of oregano essential oil against six bacteria strains: Bacillus cereus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Salmonella Typhimurium. Three concentrations of oregano essential oil were employed: 1.0 percent, 2.0 percent and 5.0 percent. Bacterial growth inhibition was determinate as the diameter of the inhibition zones.

Oregano essential oil showed antibacterial activity against spoilage microorganisms, at different concentrations, except for P. aeruginosa. There was a significant difference between methodologies only for the microorganism S. aureus. The results provided evidence of the existence of significant differences among the concentrations of oregano essential oil for each microorganism evaluated.

Although the research for this paper involved only oregano essential oil, it provided a starting‐point for further investigations concerning spices as natural preservatives for food systems.

Disc and well‐assays were found to be simple and reproducible practical methods. Other spices, their essential oil and extracts might be researched against other micro‐organisms. Furthermore, in situ studies need to be performed to evaluate possible interactions between essential oils and compounds naturally present in food against microbial strains.

The imminent adoption of measures to reduce the use of additives in foods and the reduction on using such compounds.

This study provides insights that suggest a promising exploratory development of food natural preservative against spoilage microorganisms in food systems by the use of oregano essential oil.

The purpose of this paper is synthesis and evaluation of antioxidant and antibacterial activities of a series of new azo dyes derived from 4-aminostilbene.

First, the starting material 4-aminostilbene was prepared via two successive Wittig and reduction reactions from 4-nitrobenzyl bromide. The obtained 4-aminostilbene was then reacted with some phenols under the normal azo coupling reaction conditions to give five new azo products. Antioxidant activity of the azo compounds was determined by radical scavenging assay using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. Also, the antimicrobial activity of the compounds against one gram-positive and eight gram-negative strains was evaluated based on the inhibition zone using disc diffusion assay.

The structures of the azo dyes were identified and characterized by fourier-transform Infrared, 1H nuclear magnetic resonance (NMR) and ultraviolet-visible (UV-V) is spectroscopic methods. All the compounds showed higher antioxidant activity than ascorbic acid (Asc) and butylated hydroxytoluene (BHT) as positive controls. Moreover, the compounds showed lower antibacterial activity than the standard antibiotic vancomycin.

Excellent antioxidant activity, along with antibacterial activity against Streptococcus pneumoniae and Pseudomonas aeruginosa, was observed for the two synthesized azo dyes.

Five novel azo dyes based on 4-aminostilbene were synthesized. The dyes have a highly p-extended conjugated structure comprising the phenolic and stilbenic segments, and they indicated good antioxidant activity, so that the two dyes (2c and 2d) even showed much more scavenging activity compared to BHT which is used as an antioxidant agent in food industries. These compounds with highest antioxidant activity also inhibited the growth of S. pneumoniae and P. aeruginosa.