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The increasing production and utilization of synthetic polymers in the textile industry over the past five decades has raised concerns about the environmental impact of the industry. The recalcitrant nature of synthetic fibers hampers the biodegradation of these textiles in the environment and leads to the accumulation of textile waste. Effective solutions for recycling and proper disposal of textile waste are lacking, however, the use of microorganisms and enzymes has emerged as a promising approach. The genus Streptomyces has been well studied as a producer of different hydrolytic enzymes, several of which have found use in industrial settings as well. As an integral part of the soil microbiome, Streptomyces species have been shown to interact with different textile materials in soil and may play a role in the degradation of these materials. This study aimed to examine the interaction of Streptomyces sp. R1, isolated from the rhizosphere of Cotinus coggygria, with polyamide/polyurethane textile, and identify potential enzymes involved in the biodegradation of synthetic textiles. The degradation of the textile was tested in liquid cultures (minimal salt medium) and model compost, bio-augmented with Streptomyces sp. R1 for 4 months. After the incubation, morphological, and changes in the functional groups of the textiles were analysed using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The surface of the textile showed noticeable cracks and fissures after 4 months of burial in the bioaugmented model compost, alongside changes in the functional groups of the polyamide/polyurethane textile, which indicates biodegradation of the synthetic fibers. Searching the genome of Streptomyces sp. R1, several enzymes involved in the degradation of synthetic polymers were identified, including an esterase homologous to highly efficient plastic degrading depolymerases. Overall, the results presented here indicate Streptomyces sp. R1 has the

Predloženo tehničko rešenje opisuje tehnološki postupak za dobijanje antimikrobnih aerogelova skroba. Bioaktivni materijala su proizvedeni primenom ekološki prihvatljivih tehnika upotrebom zelenog medujuma (natkritičnog ugljen(IV)-oksida), biokompatibilnih i biorazgradivih materijala iz obnovljivih izvora i prirodnih bioaktivnih jedinjenja. Zeleni medijum se u potpunosti uklanja iz finalnog proizvoda i može se reciklirati nakon proizvodnje. Proizvedeni aerogelovi skroba sa timolom, eugenolom, karvakrolom i citronelolom (12,815,8 mass%) pokazuju jaku antimikrobnu aktivnost. Dobijeni aerogelovi se mogu upotrebiti u medicini za tretiranje inficiranih rana jer apsorbuju do 265 do 569% okolne tečnosti i inhibiraju rast Gram-negativnih bakterija, Gram-pozitivnih bakterija i gljivica (veličina prečnika zone inhibicije je do 37,5 mm). Predmetno tehničko rešenje pokazuje obećavajući zeleni pristup za proizvodnju bioaktivnih dvokomponentnih materijala na bazi skroba za potencijalnu primenu u lečenju infekcija kože. Ovim rešenjem prevazilaze se ekološki problemi stvaranja otpada prilikom proizvodnje bioaktivnih materijala i korišćenjem proizvedenog materijala izbegava se akumulacija otpada nakon upotrebe.

Aerogels are materials with high specific surface area and high porosity, which can be produced from polysaccharides such as starch [1,2]. Starch is an abundant and low-cost polymer with versatility in processing. Aerogel properties are influenced by the process parameters including starch-to-water ratio, gelatinization temperature (T), selection of non-solvent for water replacement in hydrogels, selection of drying method, drying pressure (P) and T, etc. [1,2]. Supercritical drying, which employs supercritical carbon dioxide (scCO2), is an environmentally friendly process that allows relatively fast production of aerogels. Despite the superior properties of starch aerogels, they do not express biological activity. This can be overcome by the incorporation of bioactive compounds (BCs) into aerogels using the supercritical impregnation (SCI) process [3,4]. SCI implies the dissolution of BCs in scCO2, diffusion of BC-scCO2 solution into a polymer matrix, possible chemical or physical interaction of BC with polymer, and complete removal of scCO2 from the BC-polymer after a decrease of P and T to atmospheric. This process allows one-step production of solvent-free added value materials at relatively low T and the incorporation of high amounts of BC with various biological activities. Aerogels can be impregnated with pharmaceutical drugs but also with natural BCs (single or mixture) such as plant extracts [3,4]. To produce aerogels, 10 g of cornstarch (amylose content 20−30%, HeMoss, Serbia) was mixed with 100 mL of distilled water, gelatinization T was changed from 70 to 100 °C, water contained in hydrogels was replaced with acetone or ethanol during 1 or 5 days, drying P was varied from 8 to 20 MPa while drying T was 35 or 40 °C. Drying of gels was performed in a 25 mL high-pressure view cell while impregnation of aerogels with BCs was performed in a 280 mL high-pressure unit (Eurotechnica GmbH, Germany). Developed aerogels were tested as possible carriers of hemp and

The syntheses of Ag-based nanoparticles (NPs) with the assistance of plant extracts have been shown to be environmentally benign and cost-effective alternatives to conventional chemical syntheses. This study discusses the application of Paliurus spina-christi, Juglans regia, Humulus lupulus, and Sambucus nigra leaf extracts for in situ synthesis of Ag-based NPs on cotton fabric modified with citric acid. The presence of NPs with an average size ranging from 57 to 99 nm on the fiber surface was confirmed by FESEM. XPS analysis indicated that metallic (Ag0) and/or ionic silver (Ag2O and AgO) appeared on the surface of the modified cotton. The chemical composition, size, shape, and amounts of synthesized NPs were strongly dependent on the applied plant extract. All fabricated nanocomposites exhibited excellent antifungal activity against yeast Candida albicans. Antibacterial activity was significantly stronger against Gram-positive bacteria Staphylococcus aureus than Gram-negative bacteria Escherichia coli. In addition, 99% of silver was retained on the samples after 24 h of contact with physiological saline solution, implying a high stability of nanoparticles. Cytotoxic activity towards HaCaT and MRC5 cells was only observed for the sample synthetized in the presence of H. lupulus extract. Excellent antimicrobial activity and non-cytotoxicity make the developed composites efficient candidates for medicinal applications.

Intensified oil exploitation accompanied with frequent oil spills having a detrimental impact on ecosystems are seeking efficient, environmentally and economically feasible solutions. In an attempt to develop an efficient, reusable, biodegradable and cheap sorbent for oil clean-up non-woven sorbents based on recycled jute post-industrial textile waste were fabricated. The influence of area density of non-woven sorbents and hydrophobicity of fibers on overall oil sorption performance was the focus of this research. All sorbents showed a good reusability after five sorption cycles and buoyancy in water even after 24 h independently of sorbent structure. The area density of sorbents and viscosity of studied oils (crude oil, diesel oil and two types of motor oils) highly affected the oil sorption capacity and oil retention. The sorbent with the lowest area density exhibited the best oil sorption performance. The esterification of jute with stearic fatty acid contributed to decrease in water uptake of sorbents but also to negligible change of oil sorption behavior indicating that the structure of the sorbent in this case plays a crucial role.

Natural compounds found in different plant extracts can show numerous biological activities and be used as health promoters. For instance, thymol, carvacrol, citronellol, and eugenol (found in extracts of thyme, oregano, lemongrass, and clove, respectively) can be used as anti-inflammatory, antiviral, and antimicrobial agents [1- 4]. The high volatility of the mentioned natural bioactive compounds (NBCs), which restricts their broader application, can be managed by the incorporation of NBCs into polymer matrices. Therefore, intending to develop devices that release antimicrobial substances in a controlled manner, this study tested the applicability of the supercritical solvent impregnation (SSI) technique for the incorporation of NBCs into starch aerogels. First, the hydrogels were prepared from corn starch. The water in the hydrogels was replaced by ethanol, and the obtained alcogels were dried using the supercritical drying (SCD) technique. The parameters of the aerogels` preparation were optimized previously [5].Later, SSI was performed at 150 bar and 35 °C for 2 h. The obtained materials were analyzed using FTIR, to determine the potential interactions between the NBCs and polymer that could determine the rate of controlled release and antimicrobial activity. Controlled release of NBCs from the aerogels was tested in phosphate-buffered saline solution at 37 °C. ...

Efikasno i jeftino čišćenje naftnih mrlja sa vode i tla kao i generisanje ogromnih količina tekstilnog otpada su goreći ekološki problemi koji zahtevaju hitno rešavanje. U pokušaju da se odgovori na oba izazova, proizveden je iglovani netkani sorbent od recikliranih vlakana jute iz industrije tepiha. Ispitan je uticaj površinske mase i debljine sorbenata na sorpcioni kapacitet za naftu u vodi i u nafti bez vode, sposobnost plutanja, sposobnost zadržavanja nafte i mogućnost ponovne upotrebe. Svi sorbenti su položili test plutanja. Površinska masa sorbenata i viskozitet testirane nafte i naftnih derivata (sirova nafta, dizel gorivo i dva motorna ulja) imaju snažan uticaj na sorpcioni kapacitet i sposobnost zadržavanja nafte. Sorbenti uglavnom zadržavaju do 50% svojih početnih sorpcionih kapaciteta nakon 5 ponovljenih ciklusa sorpcije što ukazuje da se mogu višekratno koristiti., Efficient and inexpensive cleanup of oil spills on water or land and huge generation of textile waste are burning environmental issues that are seeking urgent solutions. In an attempt to address both challenges, needle-punched non-woven sorbents (NWSs) based on recycled jute fibers from the carpet industry were manufactured. The influence of NWS area density and thickness on oil sorption capacity in water and oil without water, buoyancy, oil retention and reusability were studied. All NWSs passed the buoyancy test. The area density of NWSs and viscosity of tested oils (crude oil, diesel oil and two motor oils) strongly affect the oil sorption capacity and oil retention. NWSs mainly retain 50% of their initial oil sorption capacities after 5 repeated sorption cycles indicating that NWSs could be used several times.

U ovom radu je ispitana mogućnost in situ sinteze nanočestica na bazi srebra primenom ekstrakta lista oraha, na pamučnoj tkanini prethodno modifikovanoj limunskom kiselinom. Tokom sinteze su formirane sferne nanočestice prečnika oko 60 nm, koje su ravnomerno raspoređene po površini pamučnih vlakana. Prisustvo nanočestica na bazi srebra je obezbedilo odličnu antimikrobnu aktivnost prema bakterijama Staphylococcus aureus i Escherichia coli, kao i kvascu Candida albicans. Tekstilni nanokompozitni materijal nije citotoksičan prema ćelijama zdravih keratinocita kože (HaCaT linija) i zdravih fibroblasta (MRC-5 linija), što omogućava njegovu bezbednu primenu za medicinske potrebe., This study discusses the possibility to utilize walnut leaf extract for in situ synthesis of silver-based nanoparticles on cotton fabric previously modified with citric acid. Synthetized spherical nanoparticles with an average diameter of 60 nm were evenly distributed over the surface of cotton fibers. The presence of silver-based nanoparticles provided excellent antimicrobial activity against bacteria Staphylococcus aureus and Escherichia coli, and yeast Candida albicans. The textile nanocomposite did not show any cytotoxicity towards healthy skin keratinocytes cells (HaCaT line) and healthy fibroblast cells (MRC-5 line). Thus, it could be considered as a safe for potential medical applications.

The demand for antimicrobial textiles is rapidly growing particularly in medical sector. In an effort to develop a simple and efficient antimicrobial treatment for cotton, layer-bylayer deposition of chitosan and magnesium lignosulfonate, followed by in situ synthesis of silver (Ag) nanoparticles, was accomplished. Lignin is exploited as a natural reducing and stabilizing agent1,2, producing Ag nanoparticles in amounts even larger than those obtained with sodium borohydride as a strong reducing agent. The influence of the number of bilayers (4 and 12) and initial concentration of AgNO3 solution (10 and 20 mM) on antimicrobial activity of cotton fabric against Gram-negative bacteria E. coli, Gram-positive bacteria S. aureus, and C. albicans, yeast was examined. The presence of evenly scattered Ag nanoparticles all over the fiber surface is confirmed by FESEM analysis (Figure 1). The number of bilayers does not affect the size of nanoparticles (~56 nm), but an increase of bilayers results in greater Ag content. The samples treated with 20 mM AgNO3 solution contain more Ag than those treated with 10 mM solution. The formation of metallic Ag nanoparticles is confirmed by XPS analysis. Synthesized Ag nanoparticles provide excellent antibacterial activity against bacteria S. aureus (99.9 %), independent of the initial concentration of AgNO3 and number of bilayers. Larger content of Ag nanoparticles i.e., higher initial concentration of AgNO3 solution leads to considerably enhanced antibacterial activity against E. coli. A similar trend is evident with the C. albicans yeast, but the desired yeast reduction of 99 % was not obtained.

Poor antimicrobial activity and lack of protection against UV irradiation are weaknesses of cotton textiles. In an attempt to impart superior antimicrobial and UV-protective properties to cotton, layer-by-layer deposition of chitosan and magnesium lignosulfonate, and in situ synthesis of silver (Ag) nanoparticles (NPs), was performed. Lignin, in a chitosan/lignin multilayer, simultaneously acts as a UV protective macromolecule and natural reducing and stabilizing agent, allowing formation of Ag NPs. Four bilayers of this coating is sufficient for fabrication of a chitosan/lignin/Ag-NP textile nanocomposite treatment with 50+ UV protection. 100% reduction of Gram-negative bacteria Escherichia coli, gram-positive bacteria Staphylococcus aureus, and yeast Candida albicans can be achieved with a 12-bilayer coating, when 20 mM silver nitrate solution and sodium borohydride are applied. On the other hand, four bilayers impregnated with Ag NPs, using 10 mM silver nitrate solution, provides sufficient antimicrobial activity independent of an added reducing agent. This treatment exhibits no inhibition of human keratinocyte cells growth on the skin, indicating low cytotoxicity.

Efikasno i jeftino čišćenje naftnih mrlja sa vode i tla kao i generisanje ogromnih količina tekstilnog otpada su goreći ekološki problemi koji zahtevaju hitno rešavanje. U pokušaju da se odgovori na oba izazova, proizveden je iglovani netkani sorbent od recikliranih vlakana jute iz industrije tepiha. Ispitan je uticaj površinske mase i debljine sorbenata na sorpcioni kapacitet za naftu u vodi i u nafti bez vode, sposobnost plutanja, sposobnost zadržavanja nafte i mogućnost ponovne upotrebe. Svi sorbenti su položili test plutanja. Površinska masa sorbenata i viskozitet testirane nafte i naftnih derivata (sirova nafta, dizel gorivo i dva motorna ulja) imaju snažan uticaj na sorpcioni kapacitet i sposobnost zadržavanja nafte. Sorbenti uglavnom zadržavaju do 50% svojih početnih sorpcionih kapaciteta nakon 5 ponovljenih ciklusa sorpcije što ukazuje da se mogu višekratno koristiti., Efficient and inexpensive cleanup of oil spills on water or land and huge generation of textile waste are burning environmental issues that are seeking urgent solutions. In an attempt to address both challenges, needle-punched non-woven sorbents (NWSs) based on recycled jute fibers from the carpet industry were manufactured. The influence of NWS area density and thickness on oil sorption capacity in water and oil without water, buoyancy, oil retention and reusability were studied. All NWSs passed the buoyancy test. The area density of NWSs and viscosity of tested oils (crude oil, diesel oil and two motor oils) strongly affect the oil sorption capacity and oil retention. NWSs mainly retain 50% of their initial oil sorption capacities after 5 repeated sorption cycles indicating that NWSs could be used several times.

Nano-finishing of textiles with metal and metal oxide nanoparticles (NPs) is relatively simple, but insufficiently efficient binding between the fibers and NPs poses a big problem because of the poor stability of textile nanocomposites. A good way to overcome this problem is to activate the fibers by plasma. Selection of gas and optimization of plasma processing parameters lead to a generation of new functional groups improving the binding of NPs. Another approach relies on the formation of stable nano-coatings by magnetron sputtering. Progress has been recently made in plasma-assisted in situ synthesis of metal NPs where toxic chemical reducing agents were replaced with short plasma treatment. This review paper addresses substantial roles of plasma, which enhance the performance of nano-finished textiles.

Creating multifunctional textiles using chemicals from renewable sources is challenging. In an effort to develop a sustainable and efficient multifunctional cotton treatment, a lignin-based multilayer nanocoating comprising magnesium lignosulfonate, chitosan, and monoammonium phosphate (MAP) was deposited using layer-by-layer assembly. A five bilayer coating adds 15.5 wt % to cotton and imparts fire extinguishing behavior and excellent UV and antimicrobial protection to the fabric. Just a two bilayer coating imparts sufficient self-extinguishing behavior to pass the standard vertical flame test. The combined influence of lignin as a char-forming and UV-protective macromolecule, chitosan as a char-forming biopolymer, and MAP acting as an antimicrobial agent (and a blowing agent and an acid source in an intumescent flame retardant system) results in a very powerful multifunctional textile treatment with very few layers of deposition.

Potrebe za medicinskim tekstilom koji poseduje antimikrobna svojstva kontinualno rastu. U poslednje vreme se cine napori da se sinteza nanocestica Ag ostvari upotrebom zelenih redukcionih sredstava, a pre svega biljnih ekstrakta. U ovom radu su nanocestice Ag sintetisane na viskoznoj tkanini modifikovanoj biopolimerom hitozanom sa i bez prisustva umreživaca 1,2,3,4-butantetrakarboksilne kiseline primenom ekstrakta kore nara kao redukcionog sredstva. Uprkos razlici u sadržaju i velicini nanocestica Ag, oba uzorka pokazuju odlicnu antibakterijsku aktivnost prema bakterijamaS. aureusi E. coli, a još bolju antifungalnu aktivnost prema kvascu C. albicans. Pri tome je citotoksicnost ovih uzoraka prema celijama keratinocita ljudske kože niska., The needs for medical textiles with antimicrobial properties are continually growing. Recently many efforts have been made to synthesize Ag nanoparticles using green reducing agents, in particular plant extracts. In this study Ag nanoparticles were synthesized on viscose rayon fabric modified with biopolymer chitosan with or without crosslinker 1,2,3,4-tetrabutanecarboxylic acid by applying pomegranate peel extract as a reducing agent. Despite the difference in content andsize of Ag nanoparticles both samples showed excellent antibacterial activity against bacteria S. aureus and E. coli and even better against yeast C. albicans. The cytotoxicity of these samples onhuman keratinocyte cellswas low.