Browsing by Author "Alpaslan, Duygu"

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3-Acrylamidopropyl Cationic Hydrogel Modified Graphite Electrode and Its Superior Sensitivity To Hydrogen Peroxide
(Taylor & Francis inc, 2019) Caglar, Aykut; Kazici, Hilal Celik; Alpaslan, Duygu; Yilmaz, Yonca; Kivrak, Hilal; Aktas, Nahit
A highly sensitive hydrogen peroxide (H2O2) sensor is fabricated by the synthesized 3-Acrylamidopropyl-trimethylammoniumchloride (p(APTMACl)) hydrogel to covered of pen- graphite (PG) electrodes. (p(APTMACl))-PG electrode is characterized using scanning electron microscopy (SEM), Fourier Transform Infrared (FTIR) spectroscopy, and thermogravimetric analysis (TGA). The electrochemical properties of these sensors are investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). The CV behavior of (p(APTMACl))-PG electrode is investigated in 0.1M PBS (pH 7, 5mm diameter of mold). The developed sensor displays significantly enhanced electrocatalytic activity through the H2O2 detection. Linear response of the sensor to H2O2 were observed in the concentration range from 0 to 130 mu M (R-2 = 0.99) with a detection limit of 1.08x10(-6) M, quantification limit of 3.62x10(-6) M (S/N=3) and sensitivity of 2375 mu A/mMcm(2). In addition, interference studies reveal that (p(APTMACl))-PG electrode is not affected by ascorbic acid (AA), uric acid (UA), and dopamine which are common interfering species. The developed sensor is also successfully applied to detect H2O2 in real commercial samples. This study describes a novel strategy to sensing characteristics to hydrogen peroxide by p(APTMACl)-PG electrode.
Agar and Sesame Oil Based Organo-Hydrogels as a Pharmaceutical Excipient in Paracetamol/Carboplatin Release Systems
(indian Pharmaceutical Assoc, 2022) Alpaslan, Duygu; Dudu, Tuba Ersen; Aktas, Nahit
Organo-hydrogels were synthesized by using free radical polymerization in the emulsion technique, using agar, glycerol, sesame oil, ammonium persulfate as initiator and N,N'-methylene bisacrylamide or glutaraldehyde as crosslinker. Swelling behaviors, blood compatibility, antioxidant and properties of the organo-hydrogels were investigated thoroughly. The highest swelling value was seen in organo-hydrogel synthesized with the N,N'-methylene bisacrylamide crosslinker containing 0.1 ml of sesame oil. Moreover, drug release behaviors of organo-hydrogels were studied as paracetamol and carboplatin used as model drugs. Release studies were shown that some basic parameters such as medium pH and composition of the polymer structure affect organo-hydrogels drug release behavior. As a result of drug release experiments, it was observed that the release values of organo-hydrogels changed depending on sesame oil and crosslinker content. The highest paracetamol release capacities for the p (AG-m-SO)(2) and p (AG-g-SO)(2) organo-hydrogels were calculated as 45.3 % and 79.8 %. When investigated carboplatin releases, the highest releases also were founded to be 100 % for p (AG-m-SO)(2) and 85 % for p (AG-g-SO)(2).
Application of Poly (agar-Co Almond Oil) Based Organo-Hydrogels as a Drug Delivery Material
(Springer, 2022) Ersen Dudu, Tuba; Alpaslan, Duygu; Aktas, Nahit
In this study, it was aimed to investigate the synthesis, characterization and drug release behaviors of organo-hydrogels containing pH-sensitive Agar (A), Glycerol (G), Sweet Almond oil (Wu et al. in J Mol Struct 882:107-115, 2008). Organo-hydrogels, which contained Agar, Glycerol and different amounts of Sweet Almond oil, were synthesized via the free-radical polymerization reaction with emulsion technique using glutaraldehyde or methylene bis acrylamide crosslinkers. Then, the degree of swelling, bond structures, blood compatibility and antioxidant properties of the synthesized organo-hydrogels were examined. In addition, Organo-hydrogels which loaded with Ceftriaxone and Oxaliplatin were synthesized with the same polymerization reaction and release kinetics were investigated. In vitro release studies were performed at media similar pH to gastric fluid (pH 2.0), skin surface (pH 5.5), blood fluid (pH 7.4) and intestinal fluid (pH 8.0), at 37 degrees C. The effects on release of crosslinker type and sweet almond oil amount were investigated. Kinetic parameters were determined using release results and these results were applied to zero and first-order equations and Korsmeyer-Peppas and Higuchi equations. Diffusion exponential was calculated for drug diffusion of organo-hydrogels and values consistent with release results were found.
Biochar-Embedded Soft Hydrogel and Their Use in Ag Nanoparticle Preparation and Reduction of 4-Nitro Phenol
(Taylor & Francis As, 2013) Sahiner, Nurettin; Karakoyun, Necdet; Alpaslan, Duygu; Aktas, Nahit
The authors report the synthesis of a composite hydrogel based on acrylamide-chicken biochar(AAm)-CBand its use as a template in the preparation of silver metal nanoparticles. Moreover, we demonstrate the efficient utilization of p(AAm)-CB composite hydrogel as a reactor vessel in the reduction of an organic contaminant 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). Experimental parameters affecting 4-NP reduction rate were investigated. The kinetics of the reduction reaction under different reaction conditions were also evaluated to determine the activation parameters. Activation energy for the reduction of 4-NP was 15.25kJmol1 and p(AAm)-CB-Ag composites possessed 99.45% activity after five repetitive uses.
Biocompatible Collagen-Synthetic Interpenetrating Polymeric Hydrogels
(Amer Chemical Soc, 2013) Sahiner, Mehtap; Alpaslan, Duygu; Bitlsli, Behzat O.
Characterization of P(Pmo), P(Lo) and P(Ro) Organoparticles, Their Bioactivity Properties and Their Effect on Pancreatic Cancer Capan-1 Cell
(Elsevier Science Sa, 2023) Alpaslan, Duygu; Turan, Abdullah; Dudu, Tuba Ersen; Bozer, Busra Moran; Aktas, Nahit; Turk, Mustafa
For the first time in the literature, p (PmO), p (LO) and p (RO) organo-particles were synthesized from Peppermint oil, Lemon oil and Rose oil. Of the organo-particles L-929 cell line viability/cytotoxicity and anticancer effect against Capan-1 pancreatic cancer cell line were investigated. p (PmO), p (LO) and p (RO) organoparticles were featured by thermogravimetry (TGA), Fourier Transform Infrared Spectroscopy (FTIR), Scanning electron microscope (SEM), Particle size (DLS), and particle charge (zeta potential, Zeta) analyses. Antioxidant, biocompatible, and antimicrobial activities and in vitro cytotoxicity specialties were investigated. In studies on Capan-1 and L-929 cell lines, it was observed that p (PmO), p (LO) and p (RO) organo-particles were effective on L-929 fibroblast cell line on Capan-1 pancreatic cancer cell line. In addition, it was observed that p (PmO), p (LO) and p (RO) organo-particles were not toxic in L-929 cell lines at high doses. When the Capan-1 cell line MTT analysis results of p (PmO), p (LO) and p (RO) organo-particles were examined, a difference was observed between cell viability rates and apoptosis and necrosis values. The highest % apoptosis rate was observed in the p (RO) organo particle.
Characterization of Particles Synthetic From Abelmoschus Esculentus L. Plant Extract and Usage in Drug Removal
(2023) Orhan, Rezan; Dudu, Tuba Erşen; Alpaslan, Duygu
Hızlı nüfus artışı ve sanayileşme sonucu yaşanan iklim değişikliği su kaynaklarının kullanımında bazı sınırlamalar getirmektedir. Özellikle endüstriyel atık suların yeterince arıtılmadan alıcı ortama deşarj edilmesi sonucunda sınırlı olan temiz su kaynakları kirlenmekte, azalmakta ve kullanılamaz hale gelmektedir. Son yıllarda yaşanan covid-19 pandemisi nedeni ile çok fazla ilaç kullanılmış ve bu ilaçların bir kısmı çevresel sulara atık olarak karışmıştır. Çevreye verilen bu ilaçlar ise, kimyasal yapılarına bağlı olarak, ekolojik dengenin bozulmasına ve bulundukları ortamdaki doğal olayların doğrudan ya da dolaylı olarak engellenmesine yol açabilmektedirler. Bu bileşiklerin zararlı etkilerinden korunmak için ilaç atıklarını içeren atık suların arıtımı oldukça büyük önem arz etmektedir. Tüm ekosistemi tehdit eden bu kirleticiler göz önüne alınarak, bu tez çalışmasında Abelmoschus esculentus L. (Ae, bamya, okra) bitki atıklarından elde edilen Ae ekstratı kullanarak emülsiyon ortamında redoks polimerizasyon tekniği ile ilk kez Ae/metal partikülleri sentezlendi ve parasetamol ilacının çevresel sulardan giderimi üzerindeki etkinliğini incelemek için laboratuvar şartlarında sorpsiyon deneyleri gerçekleştirildi. Kadmiyum ve bakır iyonları polimer sentezinde partikülün metal kısmını oluşturmak için seçildi. Daha sonra Fourier Transform Infrared Spektrofotometre (FT-IR), Taramalı Elektron Mikroskobu (SEM), Termogravimetrik Analiz cihazı (TGA), Brunauer–Emmett–Teller Yüzey Alanı Ölçüm Cihazı (BET) ve Parçacık Boyutu ve Zeta Potansiyeli Ölçüm Cihazı (Zeta Sizer) kullanılarak yapısal karakterizasyonları yapıldı. Farklı parasetamol konsantrasyonlarında (mg/L), farklı pH değerlerinde, farklı sıcaklık ortamlarında (°C), farklı partikül miktarlarında (mg) ve farklı partikül türlerinde sorpsiyon deneyleri gerçekleştirildi ve partiküllerin parasetamol sorpsiyon performansları incelendi. Aynı zamanda sorpsiyon izotermleri ve termodinamik parametreler açısından parasetamol sorpsiyonu modellendi. Yapısal karakterizasyon analizleri ile Ae/metal içerikli polimerik partiküllerin başarılı bir şekilde sentezlendiği gözlendi. Sulu ortamdan parasetamol ilaç giderimde etkili ve başarılı sonuçlar vermesi nedeniyle sentezlenen partiküllerin sorpsiyon deneylerinde mevcut malzemelerle kıyaslanabileceği öngörülmektedir.
Chemical Composition, Antimicrobial, Antioxidant and Anthocyanin Activities of Mosses (Cinclidotus Fontinaloides (Hedw.) P.beauv. and Palustriella Commutata (Hedw.) Ochyra) Gathered From Turkey
(Taylor & Francis Ltd, 2017) Yayintas, Ozlem Tonguc; Alpaslan, Duygu; Yuceer, Yonca Karagul; Yilmaz, Selehattin; Sahiner, Nurettin
Cinclidotus fontinaloides (Hedw.) P. Beauv. and Palustriella commutata (Hedw.) Ochyra were used in this study. The chemical composition of mosses in the ethanol and water extract was determined using GC-MS and FT-IR. Antioxidant activities of moss extracts were tested by total phenol and ABTS methods. Trolox equivalent value (TEAC) of mosses was calculated as 26 +/- 0.32 and 10 +/- 0.22 mg/g. The amounts of the flavonoid compounds were calculated as mg gallic acid. Gallic acid equivalent value of mosses was calculated as 587 +/- 0.55 and 496 +/- 0.22 mg/g. The extracts antimicrobial activity was tested against Escherichia coli (ATCC 8739), Bacillus subtilis (ATCC 6633), Staphylococcus aureus (ATCC 6538), Pseudomonas aeruginosa (ATCC 10145) and Candida albicans (ATCC 10231). Significant antibacterial effect was observed for C. fontinaloides and P. commutata in ethanol extract. Total anthocyanin activities of C. fontinaloides and P. commutata were determined as 50 +/- 0.17 and 144 +/- 0.33 mg/L. [GRAPHICS] .
Collagen-Based Hydrogel Films as Drug-Delivery Devices With Antimicrobial Properties
(Springer, 2014) Sahiner, Mehtap; Alpaslan, Duygu; Bitlisli, Behzat O.
Collagen (coll)-containing hydrogel films were prepared by mixing degraded collagen with monomers such as acrylamide (AAm), and 2-hydroxy ethylmethacrylate (HEMA) before the polymerization/cross-linking of composites as p(coll-co-AAm), and p(coll-co-HEMA), respectively. These materials were used as drug-delivery devices for potential wound dressing materials by loading and releasing of model drugs such as gallic acid (GA) and naproxen (NP). A linear release profile was obtained up to 32-h release from GA-loaded p(coll-co-AAm) interpenetrating polymeric networks films, and 36-h linear release profile of NP for p(coll-co-HEMA). Furthermore, metal nanoparticles such as Ag and Cu prepared within these hydrogel films offered antimicrobial characteristic against known common bacteria such as Escherichia coli, Bacillus subtilis, and Staphylococcus aureus.
Developing Poly (agar-Co Oil) Based Organo-Hydrogels for the Controlled Drug Release Applications
(2022) Olak, Tulü; Alpaslan, Duygu
Son yıllarda bitki özlü malzemeler kullanılarak yeni ürünler sentezlenmektedir. Bu ürünler yapısal ve morfolojik özellikler kazandırılarak farklı amaçlar için kullanılmaktadır. Özellikle tıp alanında ilaç salınımı için yapılan araştırmalar önem kazanmıştır. Sunulan tezde gluteraldehit (GA) ve metilenbisakrilamid (MBA) çapraz bağlayıcıları kullanılarak sentezlenen jel, hidrojel ve organo-hidrojellerin biyomedikal alanlarda kullanılabilirliği araştırıldı. Bu çalışmada Agar(A), Gliserol(G) ve Kekik Yağı (KY) bazlı organo-hidrojeller emülsiyon ortamında serbest radikal polimerizasyon tekniği kullanarak hazırlandı. Yapısal karakterizasyonları Fourier Transform Infrared Spektrofotometre (FT-IR) ve Termogravimetrik analiz (TGA) cihazları kullanılarak gerçekleştirildi. Kullanım amaçlarına uygun olarak; su, etanol, etanol/su (1:1), aseton, aseton/su (1:1), benzin ve farklı pH ortamlarında şişme davranışları incelendi. Ayrıca sentezlenen organo-hidrojellerin; kan pıhtılaşması, hemoliz ve antioksidan özellikleri incelendi. İlaç taşıyıcı özelliklerini araştırmak için poli(AG-ko-KY) bazlı organo-hidrojellere sentez aşamasında 5-Flourouracil ve Parasetamol ilaçları ayrı ayrı eklendi. İlaç yüklü organo-hidrojellerin 5-Flourouracil (pH 7.4'te) ve parasetamol (pH 2, pH 5.4, pH 7.4 ve pH 8'de) salınım mekanizması ve salınım kinetikleri incelendi. Yapılan analizler sonucunda 5-Flourouracil ve Parasetamol yüklü jel, hidrojel, organo-hidrojellerin ilaç salınım veriminin yapıya eklenen kekik yağı ile arttığı tespit edildi.
Developing Poly(agar-Co Oil) Based Organo-Hydrogels for the Controlled Drug Release Applications
(Elsevier, 2020) Olak, Tulu; Turan, Abdullah; Alpaslan, Duygu; Dudu, Tuba Ersen; Aktas, Nahit
In this study, it was aimed to investigate the synthesis, characterization and drug release behaviors of organohydrogels containing pH-sensitive Agar (A), Glycerol (G), Thyme Oil (TO). The novel organo-hydrogels containing TO were prepared in an emulsion media by the free-radical polymerization and crosslinking reactions among Agar (A), Glycerol (G), TO, N, N, methylenebisacrylamide (MBA) or glutaraldehyde (GA) reagent. Swelling ability (ethanol, acetone, ethanol/ID water (1:1), acetone/ID water (1:1) and gasoline environments and different pH), Fourier Transform Infrared Spectroscopy (FTIR) analysis and 5-Fluorouracil (5-Flu) drug release of the organo-hydrogels were profoundly determined and some structural parameters for organohydrogels such as blood clotting, hemolysis analysis, antioxidant analysis were also evaluated in this study. The FTIR spectra confirmed that the TO was bonded onto the organo-hydrogel structure, and the A, G and TO macromolecular chains interpenetrated through the MBA or GA reagent. When swelling analyzes were examined, it was determined that organo-hydrogels, which added thyme oil to the structure, swelled not only in pure water and tap water but also in organic solvents such as ethanol, acetone, ethanol/ID water (1:1), acetone/ID water (1:1) and gasoline. All of the organo-hydrogels synthesized in the light of blood clotting, hemolysis analysis, antioxidant analysis were hemocompatible and could be used within the body. The release results indicated that the organo-hydrogel p(AG-m-TO)(3) and p(AG-g-TO)(3) had the highest 84.3% and 73.3% release capacity. In addition, it was reported that the release capacities of organo-hydrogels were inversely proportional to the increased amount of TO. When 5-Flu drug release was examined in terms of kinetic models, it was observed that the release adapted to the Korsmeyer-Peppas (KPKM) model. And it was also determined that organo-hydrogels based on p(AG-m-TO) comply with the non-Fick law and organo-hydrogels based on p(AG-g-TO) comply with the Case II transport. In the light of the results obtained, their easy formability, their appropriate mechanical and physical properties make Organo-hydrogels suitable candidates for drug delivery systems.
Development of Onion Oil-Based Organo-Hydrogel for Drug Delivery Material
(Taylor & Francis inc, 2023) Alpaslan, Duygu; Dudu, Tuba Ersen; Aktas, Nahit
Agar and Glycerol (AG) based Organo-hydrogels containing different cross-linkers and different amounts of Onion Oil were prepared in order to examine the in vitro release of the antibiotic drug Ceftriaxone and the anti-carcinogenic drug Carboplatin. At preparation of the organo-hydrogels was used free radical polymerization technique in the emulsion media. As a control group, Agar-Glycerol (AG) gel and Agar-Glycerol (p (AG-m) and p (AG-g)) hydrogels were synthesized. When balance swelling rates of organo-hydrogels were examined, different swelling behaviors were observed in different solvent environments. When FTIR spectra of gel, hydrogel and organo-hydrogels were examined, it was observed that Onion Oil added different bonds to the structure or deepened existing bonds. It was observed that the drug release amount of Gel, hydrogel and Organo-hydrogels with different properties changed with cross-linker type, ambient pH and drug-polymer interactions. For this purpose, organo-hydrogels were produced containing onion oil in the mass proportion of three different. In order to determine the effect of ambient pH on release rate and amount of drug released, drug release at 4 different pH (at 2.0, 5.5, 7.4 and 8.0) was examined from drug-loaded organo-hydrogels. In organo-hydrogels containing different amounts of onion oil, it was observed that the rate of release changed as the onion oil rate increased. When the amount of the release of p(AG-m-OO) and p(AG-g-OO) organo-hydrogels was compared, it was observed that the rate of release of p AG-g-OO) organo-hydrogels was higher. This is due to electrostatic interactions between the organo-hydrogels synthesized with different crosslinkers and different amounts of onion oil, and the drug. When Ceftriaxone and Carboplatin drug release kinetics were applied, it was found that drug release of organo-hydrogels conformed to Higguci (HM) and Korsmeyer-Peppas (KM) models.
Development of Urea Uptake and Release Studies Using N, N-dimethylacrylamide/Maleic Acid/Citric Acid Based Macrogel
(Springer, 2021) Dudu, Tuba Ersen; Alpaslan, Duygu; Aktas, Nahit
Recently, the use of polymers in agricultural and horticultural applications has been seen as a solution to reduce water consumption and excess fertilizer use in particularly. In this study, macrogels were synthesized to allow fertilizer species and water to be controlled and released in the soil. A natural macrogel derived from N,N-Dimethylacrylamide (DMAAm), Maleic Acid (MA) and Citric Acid (CA) was selected because of its ability to absorb/release a large amount of water and to have modifiable functional groups. Urea, which is an abundant source of nitrogen, was chosen to model the fertilizer. The macrogel was prepared using easily available, low-cost, modifiable starting materials by redox polymerization technique. p(DMAAm-co-MA-co-CA) (DMC1) surface was modified by hydrochloric acid (HCl) and sodium hydroxide (NaOH) to obtain p(DMAAm-co-MA-co-CA)/HCl (DMC2) and p(DMAAm-co-MA-co-CA)/NaOH (DMC3), which have positively and negatively charged, respectively. After being analyzed for intermolecular interactions (Fourier-Transform Infrared Spectroscopy,FT-IR) and thermal properties (Thermogravimetric Analysis,TGA), the macrogels were tested in terms of sorption isotherms and thermodynamic parameters. However, in order to examine the urea release mechanism, the macrogels were tested using four release models such as Zero Order Kinetic Model(Z-O), First Order Kinetic Model(F-O), Higuchi(H) and the Korsmeyer-Peppas(K-P) power law. Cumulative urea release values for DMC1, DMC2 and DMC3 macrogels were calculated as 100% at pH 4 and 10, 100% at pH 6, 8 and 10, 100% at pH 4, 6, 8 and 10, respectively. Analyzes confirmed that synthesized macrogels can be good water holder for soil and can be a slow release of urea.
Disentangling the Enhanced Catalytic Activity on Ga Modified Ru Surfaces for Sodium Borohydride Electrooxidation
(Elsevier, 2021) Ulas, Berdan; Alpaslan, Duygu; Yilmaz, Yonca; Dudu, Tuba Ersen; Er, Omer Faruk; Kivrak, Hilal
Herein, multi walled carbon nanotube (MWCNT) supported RuGa nanocatalysts (RuGa/MWCNTs) are synthesized at varying atomic molar ratio via sodium borohydride (SBH) reduction method toward SBH electrooxidation (SBHE) and SBH hydrolysis (RSBH). From the X-ray diffraction (XRD) results, Ru and Ga metals are found to be in the alloy form and the average crystal size is determined as 2.77 nm. The distribution of RuGa particles on MWCNT is confirmed using SEM-EDX. These nanocatalysts were employed for RSBH and further measurements were performed to investigate their SBHE activity. For RSBH for RuGa/MWCNT nanocatalysts, one could note that Ga addition to Ru enhanced the initial rate, H-2 generation rate, and turnover frequency values and Ru99Ga1/MWCNT has the highest initial rate, H-2 generation rate, and turnover frequency value. According to the cyclic voltammetry (CV) results of the prepared RuGa/MWCNT nanocatalysts, Ru99Ga1/ MWCNT show the highest electrocatalytic activity for SBHE and this result is in line with the results of electrochemical impedance spectroscopy (EIS). In addition, chronoamperometric curves indicate that Ru99Ga1/MWCNT possesses long term stability compared to these of other nanocatalysts. Catalytic RSBH results of Ru99Ga1/MWCNT show that this nanocatalyst is more active than others. As a result, it is clear that RuGa/ MWCNT is a promising nanocatalyst for fuel cells.
Eco-Friendly and Biodegradable Dimethylacrylamide/Starch Hydrogels for Controlled Release of Urea and Its Water Retention
(2022) Alpaslan, Duygu; Dudu, Tuba Ersen
In this study, we focused on the synthesis of polymeric hydrogels that will support the sorption and controlled release of urea, which is a rich nitrogen source, from aqueous solutions and their usability in agricultural applications. N, N-Dimethylacrylamide (DMAAm) and Starch (St) were selected as monomers, and their superior properties, such as chemical stability, high sorption properties, biocompatibility, and the presence of modifiable groups, were utilized. A redox polymerization technique was used to create a poly(DMAAm-co-St)-based hydrogel that was then modified with acidic and basic agents to improve the properties of starch. The synthesized acid- and base-modified hydrogels were named DSt, DSt1, and DSt2, respectively. Swelling analyses were performed to examine the structural and morphological properties of DSt, DSt1, and DSt2 hydrogels, and Fourier-Transform Infrared Spectroscopy (FT-IR) and Thermogravimetric Analyzers (TGA) were used. Intense cross-linking, porosity, and the presence of hydrophilic groups were successfully detected by instrumental analysis and swelling results. The successful results of urea sorption by DSt, DSt1, and DSt2 hydrogels show that they can both minimize the harmful effects of urea in the environment and contain the nitrogen necessary for plants. At the same time, urea sorption behaviors were evaluated in terms of sorption isotherms and thermodynamic properties, and it was observed that urea sorption conformed to the Langmuir isotherm. The urea release results showed that DSt, DSt1, and DSt2 hydrogels exhibited different release properties in different pH solutions, and these results reached 94% at pH 6–8, 100% at pH 6, and 100% at pH 8–10, respectively. As a result of the gradual decrease in the water resources on the earth, the increase in the use of fertilizers in agricultural production, and the insufficient use of fertilizers, our study draws attention to the development and support of materials that absorb/store water, and forms of controlled release fertilizers and provides potential ease of application
Effect of Egg White Protein and Agar-Agar on Quality of Button Mushrooms (Agaricus Bisporus) During Cold Storage
(Tubitak Scientific & Technological Research Council Turkey, 2022) Saran, Erdi Yildirim; Cavusoglu, Seyda; Alpaslan, Duygu; Eren, Erkan; Yilmaz, Nurettin; Uzun, Yusuf
The commercialization of mushrooms is critical because they have a short shelf life. For this reason, we investigated the effect of agar-agar and egg white protein on weight loss, polyphenol oxidase and catalase, protein content, total phenolics, total antioxidant capacity, respiration rate, ethylene production and storability of button mushrooms. Our findings suggested that the treatment of edible coating delayed remarkably senescence and maintained the quality of button mushroom. Egg white protein coating was more effective on protein content, total phenolics, antioxidant capacity, respiration rate, and ethylene production than agar-agar coating. On the other hand, agar-agar coating was more effective on weight loss, polyphenol oxidase, catalase, and color changes. Ethylene production and respiration rate were significantly (p < 0.05) lower in edible coating-treated samples than uncoated samples. Furthermore, a positive correlation was found between total phenolic content and antioxidant activity. It can be recommended that abovementioned edible coatings could be used as a commercial treatment for maintaining the quality of button mushrooms during long-term storage period.
Effects of Storage Time and Quality in White Button Mushroom (agaricus Bisporus) on Edible Coating Materials
(2020) Şaran, Erdi Yıldırım; Çavuşoğlu, Şeyda; Alpaslan, Duygu
Bu çalışmada, Dünya'da ve Türkiye'de severek tüketilen beyaz şapkalı kültür mantarının (Agaricus bisporus), modifiye atmosfer koşullarında yenilebilir kaplama malzemelerinin beyaz şapkalı mantarlarda hasat sonu fizyolojisi üzerine etkileri araştırılmıştır. Aynı olgunlukta hasat edilen mantarlara, yenilebilir kaplama malzemeleri (Yumurta akı proteini veya Agar) kaplanarak +4 °C'de % 90-95 oransal nem koşullarında 20 gün depolanmıştır. Hasat döneminde ve hasattan sonra 5 gün aralıklarla, ağırlık kaybı, renk (L*, a*, b* C* ve Hue), ambalaj içi gaz bileşimi (O2, CO2 ve N2), protein, toplam fenolik içeriği, toplam antioksidan aktivitesi, katalaz, polifenoloksidaz (PPO), solunum hızı ve dışsal etilen miktarı belirlenmiştir. Araştırmada incelenen bütün parametreler dikkate alındığından kültür mantarının (Agaricus bisporus) +4°C'de ve % 90-95 oransal nem koşullarında 20 günlük depolanması sonucunda en iyi sonucu veren yenilebilir kaplama malzemesinin agar olduğu tespit edilmiştir
The Efficiency of Cationic-Based Hydrogels in Heavy Metal Removal From Wastewater
(Springer, 2024) Bakyt, Borkoev; Dudu, Tuba Ersen; Kalipa, Salieva; Alpaslan, Duygu
The present study draws attention to arsenic (V) (As(V)), chromium (III) (Cr(III)), and chromium (VI) (Cr(VI)) heavy metal pollutants, which have negative effects on aquatic ecosystems and indirectly pose a serious threat to the health of living things in the environment. Homopolymer and copolymer hydrogels were synthesized by the UV polymerization technique using 2-acrylamido-2-methyl-1-propansulfonic acid sodium salt (AMPS) and 3-acrlylamidopropil-trimethyl ammonium chloride monomers, and a crosslinker aimed to improve the swelling properties and metal sorption of the prepared hydrogels. The swelling balance values of hydrogels were determined by the gravimetric method in deionized water and different pH values, and their structural characterizations were carried out by Fourier transform infrared spectroscopy (FT-IR) and thermal gravimetric analysis (TGA) techniques. Sorption efficiencies and sorption capacities of the synthesized hydrogels were determined using aqueous solutions containing As(V), Cr(III), and Cr(VI) heavy metal ions at 25 degrees C. It was determined that there was a significant increase in p(AMPS) (AM1)-based hydrogel's balance swelling value in deionized water compared to p(AP1) and p(AMPS-co-APTMACl) (AMAP1)-based hydrogels. The lowest equilibrium swelling value was reached in the AMAP1 hydrogel, and the main reason for this result was thought to be due to the closure of the active functional groups of the increased cross-links between AMPS and APTMACl monomer. When sorption results were examined, it was observed that the highest heavy metal ion removal for AM1, AP1, and AMAP1 was in As(V) metal. The highest metal ion holding capacity of AM1, AP1, and AMAP1 was found to be 494 mg/g, 2336 mg/g, and 1439 mg/g for As(V), 323 mg/g, 111 mg/g, and 276 mg/g for Cr(III), and 303 mg/g, 723 mg/g, and 554 mg/g for Cr(VI), respectively. Considering the swelling and sorption results, it is thought that the synthesized hydrogels will provide a significant advantage in the removal of heavy metal ions, which have negative effects on environmental pollution and live health.
Environmental Usage of Poly(2-Acrylamido Acid Sodium Salt -Co Ammonium Chloride)-Lentinus Tigrinus (Bull.) Fr. Composite Hydrogel
(Amer Chemical Soc, 2016) Alpaslan, Duygu; Ersen, Tuba; Kubilay, Senol; Uzun, Yusuf; Savran, Ali; Aktas, Nahit
Evaluation of Particle Biosynthesis, P(Okra) Particle Bioactivity, and Drug Release Properties Using Abelmoschus Esculentus (Okra) Plant Extract
(Springer, 2024) Alpaslan, Duygu; Turan, Abdullah; Dudu, Tuba Ersen; Aktas, Nahit
Interest in synthesizing functional materials from natural compounds has increased recently. For this reason, compound particles attract attention due to their multifunctional properties. Abelmoschus esculentus L. (Okra) is a vegetable species belonging to the Hibiscus family, widely used for its edible unripe fruit. This study synthesized the particle from the Abelmoschus esculentus (Okra) extract (Oe) by emulsion polymerization. In this synthesis, ammonium persulfate (APS, initiator) to form free radicals at the Abelmoschus esculentus (Okra) extract (Oe) and ethylene glycol di methacrylate to cross-link the formed radicals were used. The synthesized poly(Okra) ((p(O)) particles structure Field emission scanning and Fourier transform infrared and biological activities (biocompatible, antioxidant, antimicrobial, and hydrogen peroxide scavenging) were characterized. The p(O) particle showed good antimicrobial activity against Staphylococcus aureus, Bacillus cereus, Enterococcus faecalis, and Candida albicans. It has been measured to have high antioxidant and hydrogen peroxide scavenging activity with p(O) particles.