This study presents a comparative evaluation of chitosans derived from fungi (Agaricus bisporus) and mealworms (Tenebrio molitor) as sustainable antibacterial finishing agents for textile applications. The structural properties of fungal and insect chitosans were determined using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), thermogravimetric analysis, and elemental analysis. The applicability of fungal and insect chitosans to cotton fabrics, the antibacterial activity they impart to the fabric, and the durability of this antibacterial activity after washing were evaluated using the standardized Japanese Industry Standard L 1902 methodology. The analysis results showed that mealworm chitosan exhibited higher thermal stability (maximum degradation temperature of 325 degrees C for mealworm and 309 degrees C for fungal) and a higher degree of deacetylation (79.65% for mealworm and 8.7% for fungal) than fungal chitosan. FTIR spectroscopy and SEM analyses demonstrated that fungal and insect chitosans were physically bound to the fabric surface. Both chitosans were observed to impart good antibacterial activity (A = 3.86 for mealworm and A = 3.61 for fungal; >= 99.9% reduction) to the fabric surface. Consequently, this study demonstrates the usability of alternative chitosan sources in the textile industry while also identifying the limitations of these systems in terms of wash resistance, thereby providing a concrete roadmap for future research.

In this study, a new pH-sensitive chitosan (CS)/Polyvinyl Pyrrolidone (PVP)/2-acrylamido-2-methyl-propanesulfonic acid (AMPS)/AgNO3 grafted gauze was produced using gamma radiation polymerization. The swelling, swelling kinetics, and pH-sensitivity properties of the prepared CS/PVP/AMPS/AgNp-g-gauze were tested. The model drug preferred in this study was Methylene Blue (MB). FT-IR and SEM analysis have confirmed that CS/PVP/AMPS hydrogel composite-g-gauze was successfully synthesized. It was found that there was an increase in the grafting percentage with increasing AMPS monomer concentration in the formulation. Adding different concentrations of AgNO3 to the reaction medium caused no drastic change in the grafting percentage. Swelling kinetics from the new hydrogel composite-g-gauze was best fitted to both Peppas model and the second-order kinetic equation. Swelling, pH-sensitivity, and swelling kinetics of the hydrogel composite-g-gauze were improved with the addition of CS, PVP, and AMPS in the gel formulation.

Novel pH- and temperature-responsive semi-interpenetrating network (s-IPN) microspheres were developed via a three-step approach, involving radiation grafting of sodium alginate (SA) onto a poly(N-isopropylacrylamide) (PNIPAAm) /poly(itaconic acid) (PIA) microsphere matrix. In the first step, PNIPAAm microspheres were prepared using the inverse suspension polymerization technique. In the second step, a selected fraction of PNIPAAm microspheres (180-250 & micro;m size range) was used to prepare PNIPAAm/PIA graft copolymers via the radiation-induced modification technique. Subsequently, PNIPAAm/PIA microspheres were immersed in an SA solution, followed by gamma radiation-induced polymerization at a dose of 25 kGy. The prepared s-IPN microspheres were characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analyses. The swelling kinetics of the novel s-IPN microspheres were best described by the Peppas model. The n > 0.5 value in the Peppas model indicates that the mechanism is non-Fickian transport. The swelling behavior, pH-sensitivity, swelling kinetics, and hydrolytic degradation properties of the new s-IPN microspheres were improved by the incorporation of SA and itaconic acid (IA) into the gel structure.

In this study, the novel gelatin based in situ hydrogel nanocomposites were prepared from incorporating clinoptiolite (CL) and Lidocaine (LD) as a model local anesthetic drug within polyacrylamide-g-gelatin (PA-g-GA) hydrogel during the synthesis by free radical polymerization. The prepared PA-g-GA, PA-g-GA/CL and drug loaded PA-g-GA/CL in situ hydrogel nanocomposites were analyzed by FTIR and SEM. The drug release behavior of the synthesized composite hydrogel was investigated with UV-Vis spectrophotometry. Swelling and drug release behavior of the new prepared hydrogel nanocomposites were investigated with different CL and drug content in the gel structure. FTIR and SEM analysis revealed that the LD loaded PA-g-GA/CL nanocomposite was successfully prepared. Drug release (%) decreased when the drug loading and CL amount in the composite increased. Various kinetic models for all drug release data were applied in order to study drug release behavior. Korsmeyer-Peppas model fitted for the drug release data of all samples. Swelling, drug release properties of the new nanocomposites were improved with the incorporation of clinoptiolite in the gel structure.

In this study, the novel nanocomposites were prepared from the natural biopolymers, chitosan (CS), sodium alginate (SA) and clinoptiolite (CL) particles, and also having glutaraldehyde as a crosslinker by cryogelation technique. CS biopolymer was produced from crayfish Astacus leptodactylus. Characterization of the prepared CS, CS-co-SA (CS/SA) and drug loaded CS/SA/ CL nanocomposite were performed by Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) analyses. The anesthetic drug release behavior of the prepared nanocomposite was investigated for the model drug lidocaine (LD) using UV-Vis spectrophotometry and High Performance Liquid Chromatography (HPLC) techniques. The effect of different LD and CL content on the drug release behavior of the prepared nanocomposite were studied. LD release data was fitted to various kinetic models to study the drug release behavior. The LD release from all the prepared nanocomposite hydrogels fitted the Korsmeyer-Peppas model. The swelling and drug release properties of the new CS-based nanocomposite hydrogels were improved with the inclusion of SA and CL in the gel structure.

In this study, chitosan was produced from crayfish Astacus leptodactylus, and then it was used to synthesize chitosan-graft-β-cyclodextrin (CS-g-β-CD) hydrogel. The produced chitosan (CS) and the sythesized CS-g-β-CD hydrogel were characterized using a Fourier Transform Infrared Spectroscopy (FTIR), Proton Nuclear Magnetic Resonance Spectroscopy (1H-NMR), X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM). Tenofovir disoproxil fumarate (TDF) was used as a model to investigate the antiviral drug release properties of the CS-g-β-CD hydrogel. The synthesized hydrogel had an almost homogeneous pore structure and a high swelling capacity which increases depending on the amount of β-Cyclodextrin (β-CD). The drug-loaded CS-g-β-CD hydrogels was examined by XRD and 1H-NMR, and SEM analyses. Seventy-three percent of the TDF loaded on the synthesized hydrogels was released into phosphate-buffered saline (PBS) solution at 37 ºC. The drug release behavior of all prepared CS-g-β-CD hydrogels fitted the Korsmeyer-Peppas model. The addition of β-CD into the gel improved the swelling ability and TDF release of the CS-g-β-CD hydrogel system.

In this study, biomineralized polyp leaf spicules and the endoskeletal axis of the coral Pteroeides spinosum were physicochemically characterized by FTIR, SEM, EDX, TGA, XRD, ICP-MS, and ICP-OES analyses. The mineralized inner axis and polyp leaf spicules of P. spinosum were also pulverized and incorporated into the polyacrylamide (PAAm) hydrogel structure. In vitro bioactivity of coral polyp leaf spicules was evaluated by using simulated body fluid. Characterization analyses identified the major crystalline phase of coral polyp leaves spicules and the inner axis as calcite. The coral’s inner axis exhibits a notched and perforated surface morphology. Calcite sclerites obtained from polyp leaves exhibit a crystalline structure and smooth surface morphology. TGA results revealed the organic matter in the coral individual is higher than that of the polyp leaf spicules. It resulted the coral’s inner axis was compatible with the PAAm hydrogel. Coral polyp leaf spicules did not form apatite on their surface in simulated body fluid. The calcite content of the coral P. spinosum can be evaluated as an inert additive to improve mechanical properties and thermal stability in hydrogels.

At this study; Chitosan was obtained from crayfish and identified by X-ray diffraction (XRD), molecular weight and elemental analyses. Later, it was coated on fabrics alone and in combination with nano-metal.The protective properties of the coated fabrics was investigated by UV protection and antibacterial analyses. Crayfish chitosan had low crystallinity (72%), low molecular weight (Mw) (11.2 kDa) and low degree of deacetylation (DD) (16%). When used together, nano-TiO2 reduced the UVprotection of the crayfish chitosan in both dyed and undyed denim fabrics.Chitosan+Nano-Ag coated fabric had the highest antibacterial activity (Antibacterial activity value (A): 4.27) against Staphylococcus aureus while chitosan+Nano-TiO2 coated fabric did not show any antibacterial efficiency (A: 1.89). Afterwashed, the chitosan coated and the chitosan+Nano-Ag coated fabrics retained their antibacterial efficiency.

In this study, chitosan is obtained from the waste shells of crayfish ( Astacus leptodactylus ) and characterized. The crayfish chitosan was coated on cotton fabrics using the padding-drying method. The surface properties, flammability and water and air permeability properties of these coatings based on chitosan and a combination of chitosan and nano-TiO 2 were determined. The weight of green calico fabric increased to 24.76% after coating with chitosan, while the weight of the blue dyed denim fabric increased to 5.19%. The chitosan coating increased the tear strength of the calico fabric by 20% in the weft direction. Thermogravimetric analysis and vertical burning tests show that chitosan improves the thermal resistance and flame retardancy performance of denim fabrics. While the amount of residue due to thermal degradation of the blue dyed denim fabric was 16.78%, it increased to 34% after coating with chitosan+nano-TiO 2 . The chitosan coating reduced the mass loss caused by thermal degradation in green calico fabric from 86.3% to 66.0%. Chitosan also improved the post-flame combustion performance of fabrics. While the ember burning time is decreased to 6s in the chitosan-coated dyed calico fabric, this did not occur in the chitosan+nano-TiO 2 -coated dyed denim fabric. Keywords Crayfish chitosan , denim fabric , nano-TiO , thermal stability , flame retardant textile

In this study, chitosan is obtained from the waste shells of crayfish (Astacus leptodactylus) and characterized. The crayfish chitosan was coated on cotton fabrics using the padding-drying method. The surface properties, flammability and water and air permeability properties of these coatings based on chitosan and a combination of chitosan and nano-TiO2 were determined. The weight of green calico fabric increased to 24.76% after coating with chitosan, while the weight of the blue dyed denim fabric increased to 5.19%. The chitosan coating increased the tear strength of the calico fabric by 20% in the weft direction. Thermogravimetric analysis and vertical burning tests show that chitosan improves the thermal resistance and flame retardancy performance of denim fabrics. While the amount of residue due to thermal degradation of the blue dyed denim fabric was 16.78%, it increased to 34% after coating with chitosan+nano-TiO2. The chitosan coating reduced the mass loss caused by thermal degradation in green calico fabric from 86.3% to 66.0%. Chitosan also improved the post-flame combustion performance of fabrics. While the ember burning time is decreased to 6s in the chitosan-coated dyed calico fabric, this did not occur in the chitosan+nano-TiO2-coated dyed denim fabric.

Marine Protected Areas (MPAs) and their management have become more significant than ever due to the growing impacts of pollution, overfishing and illegal hunting activities in marine environments. Corals, as habitat forming species that create biodiversity hotspots, provide structural support, shelter and a nursery ground for associated biota. The present paper deals with the pre-assessment of invertebrate assemblages living in hard coral (Cladocora caespitosa) reef in the marine protected area (Dardanos Cladocora Reefs) of the Çanakkale Strait. In the study (DarINVERTA7) conducted between 2017 and 2021, 62 benthic invertebrate species, belonging to eight taxonomic groups were reported for the first time from the region of which five species (Clathria (Clathria) compressa, Rynchozoon neapolitanum, Hornera frondiculata, Polycitor adriaticus and Aplidium nordmanni) were new for the Turkish coasts.

The interest in environment-friendly production technologies has significantly increased the production of functional textile products that protect the environment and human health. In this chapter, chitosan, which is a natural biopolymer obtained from shrimp, is characterized and its antimicrobial activity against bacteria and yeast species is determined. Chitosan was coated on cotton, wool, and for the first time on denim fabrics (99% cotton and 1% elastane) to reveal how the antibacterial activity of shrimp chitosan has changed after it was coated on textile materials. The antibacterial activity against Staphylococcus aureus was investigated comparatively by qualitative and quantitative methods before and after washing. In order to improve the washing resistance of the shrimp chitosan on textile materials, chitosan–acrylic binder coatings were prepared for the first time. Chitosan can be used as a good antibacterial agent in the production of nonwashable, disposable medical textiles and skin contact textiles both alone and in composites.

The finishing process with the antibacterial agents that protect the environment and human health is gaining importance. This study aims 1) to develop new generation antibacterial finishes using chitosan as a binder for nano-Ag coatings, 2) to determine the applicability of chitosan from shrimp and crayfish for textile production and 3) to contribute to environmentally friendly textile production. Chitosan from shrimp and crayfish wastes were used as adhesive in the binding of nanoparticles to fabric surfaces. The bonding properties of the nano-Ag particles on the fabric surfaces were investigated by Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and Energy dispersive x-ray spectroscopy (EDX) analysis. The antibacterial effectiveness of fabrics against Escherichia coli ATCC 8739 were tested according to JIS L 1902-2015 standard The crayfish and shrimp chitosan formed a colorless film and coated the nano-Ag particles homogeneously on the cotton fabric. Antibacterial activity values were calculated as 3.10 and 5.74 for crayfish and shrimp chitosan coated cotton fabrics and as 5.37 and 5.10 for crayfish and shrimp chitosan+nano Ag coated cotton fabrics, respectively. Chitosan nano-Ag coating which exhibited a good antibacterial activity (99.99% reduction) against E. coli ATCC 8739 can be used in the manufacture of garments such as medical textiles, baby clothes, and underwear. The use of chitosan as a binder can reduce the use of chemicals in textile printing and pigment dying in finishing materials, pollutant discharges and emissions from industrial sources. Also, it presents innovative solutions for the protection of human and environmental health.

In this work, a new chitosan (CS)/hyaluronic acid (HA)/hydroxyapatite (HAP) hydrogels were synthesized by using gamma rays irradiation technique for oral delivery of drugs. The hydrogelss were characterized using fourier transform infrared spectroscopy (FTIR) and the physicochemical properties of shrimp chitosan was determined with both FTIR and scanning electron microscopy (SEM). The use of the hydrogel samples as a drug delivery system was investigated by an anticancer drug. 5-Fluorouracil (5-FU) was used as a model anticancer drug to investigate the drug uptake and release kinetics of hydrogels. The properties of the hydrogels were evaluated in terms of swelling, drug uptake and release behaviours. The addition of hyaluronic acid and hydroxyapatite in the gel structure improved drug uptake and release capability of the new hydrogels.

Chitin is an important polysaccharide found as supporting material in the cell wall of mushrooms. In this study, chitin and chitosan were obtained from the cell wall of two different mushroom species using chemical method and physicochemically characterized. The dry weight chitin contents of the mushroom species were determined as 11.4% for Lactarius vellereus and 7.9% for Phyllophora ribis. Chitosan yields of the chitins isolated from L. vellereus and P. ribis were 73.1% and 75.3%, respectively. While, the maximum degradation temperatures of vellereus and P. ribis chitins were found to be 354 degrees C and 275 degrees C by thermogravimetric analysis (TGA), the maximum degadation temperature of the chitosans obtained from these chitins were recorded as 262 degrees C and 229 degrees C, respectively. The crystalline index values of L. vellereus and P. ribis chitins were calculated as 64% and 49%, respectively according to the X-ray diffraction analysis (XRD) results. The scanning electron microscopy (SEM) indicated that there were no nanofiber or nanopores on the surface of the chitins and chitosans obtained from these two mushroom species. The results of this study revealed that L. vellereus and P. ribis had higher chitin contents than some other insects and mushroom species recorded in the literature and these species may be used as a potential chitin sources.

Chitin was isolated using the classical chemical method from the shell of Callinectes sapidus. The chitin content in the dry weight of the crab shells was determined as 12.1%. Total chitosan yield was recorded as 76%. The deacetylation degree of the chitosan was found to be 82.5%. The obtained chitin was in the alpha-form which was confirmed from the results of FTIR, TGA and XRD analyses. Resulting chitin showed DTG max value as 390 degrees C while in same regard chitosan show this value as 306 degrees C. Detailed information about the composition of pores and nanofibers was obtained using SEM. Disc diffusion method used for testing the antimicrobial activity, inhibition zone diameters of the chitosan from C. sapidus varied between 15.28 and 20.21 mm for human bacterial pathogens, between 15.51 and 16.25 mm for fungal pathogens and between 14.22 and 15.75 mm for fish bacterial pathogens, respectively. MBC and MFC values of the chitosan from C sapidus were between 0.16 and 2.50 mg/mL. The results of DPPH and ferric ion reducing power activity used for determining the antioxidant activity of the chitosan, were found as IC50: 5.99 and EC50: 6.16, respectively. (C) 2015 Elsevier Ltd. All rights reserved.

Chitin in the compound eyes of arthropods serves as a part of the visual system. The quality of chitin in such highly specialised body parts deserves more detailed examination. Chitin in the corneal (ommatidial) lenses of dragonfly (Sympetrum fonscolombii) compound eyes was isolated by using the classical chemical method. The chitin content of the corneal lenses was determined to be quite high (20.3±0.85%). The FT-IR analysis showed that corneal lens chitin was in the α-form as found in all arthropod species where mechanical strength is required. The surface morphology analysis by scanning electron microscopy revealed that the outer part of corneal lenses consisted of long chitin fibrils with regular arrays of papillary structures while the smoother inner part had concentric lamellated chitin formation with shorter chitin nanofibrils. Chitinase enzymatic digestion studies, elemental analysis results and the degree of acetylation value showed the purity of chitin samples from corneal lens. The maximum degradation temperature value of the corneal lens chitin was observed at 369.2°C. X-ray analysis revealed that corneal lens chitin has high crystallinity index; 96.4%. Identification of chitin found in ommaditia of insect compound eyes can provide insights into insect vision and chitin-based optical material design studies.

The chitosan from ephippia of Ceriodaphnia quadrangula (Crustaceae) has been fully characterized in our previous study, and in this work it was tested for antibacterial and antifungal activities against human and fish pathogens, while also determining its antioxidant activities. Using the disc diffusion method showed that the antimicrobial activity was observed against all tested microorganisms in the range of 12.84 -16.28 mm. The minimal bactericidal concentration (MBC) value was found to be 0.63 - 2.50 mg/ml. Chitosan obtained from C. quadrangula ephippia showed higher antimicrobial activity against some pathogenic bacteria than commercial antibiotics. While chitosan inhibited 35.83% of the 1,1-diphenyl-2-picrylhydrazyl radicals (at 5 mg/ml), it showed an activity of 14.48 mu g/ml for ferrous ion reducing. Consequently, it is suggested that chitosan obtained from the ephippia of C. quadrangula (Crustacea) can be used as food/feed additives, preservatives or in the pharmaceutical industry instead of using synthetic antimicrobials and antioxidants.

This is the first study to explain the differences in the physicochemical properties of chitin and chitosan obtained from the nymphs and adults of Dociostaurus maroccanus using the same method. Fourier transform infrared spectroscopy, thermogravimetric analysis and x-ray diffraction analysis results demonstrated that the chitins from both the adults and nymphs were in the α-form. The chitin contents of the adults (14%) and nymphs (12%) were of the same order of magnitude. The crystalline index values of chitins from the adult and nymph grasshoppers were 71% and 74%, respectively. Thermal stabilities of the chitins and chitosans from adult and nymph grasshoppers were close to each other. Both the adult (7.2kDa) and nymph (5.6kDa) chitosans had low molar masses. Environmental scanning electron microscopy revealed that the surface morphologies of both chitins consisted of nanofibers and nanopores together, and they were very similar to each other. Consequently, it was determined that the physicochemical properties of the chitins and chitosans from adults and nymphs of D. maroccanus were not very different, so it can be hypothesized that the development of the chitin structure in the nymph has almost been completed and the nymph chitin has the same characteristics as the adult.