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WOS: 000483634100050, Carbon quantum dots (CQDs) have attracted growing interest due to their superior luminescent properties, which make them excellent photosensitizers for TiO2. This study presents the green-synthesis of CQDs from edible mushroom Agaricus bisporus through microwave irradiation. In the study as-synthesized CQDs were used as a sensitizer for TiO2 in photocatalytic hydrogen evolution in aqueous triethanolamine (sacrificial reagent) under visible-light irradiation. Photocatalytic hydrogen production activity of CQD-sensitized TiO2 was found to be 472 mu mol g(-1) h(-1) (without loading any noble metal co-catalyst) and 1458 mu mol g(-1) h(-1) (with loading Pt co-catalyst). The study revealed that the CQDs from mushroom A. bisporus can be used as an efficient sensitizer for TiO2 in photocatalytic hydrogen production. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

WOS: 000482176800112, PubMed: 31460346, In biology, the activity of enzymes is usually regulated by feedback loops, which enables direct communication between enzymes and the state of the cell. In a similar manner, with the intention to have automated activity regulation, the therapeutic effect of a photosensitizer (BOD1) is shown to be reduced through a negative feedback loop initiated by the photosensitizer. Photodynamic action produces cytotoxic O-1(2) and this reactive oxygen species reacts with ascorbate, generating H2O2. Peroxide-mediated oxidation of the photosensitizer auxiliary group leads to the formation of inactive BOD2 from the parent photosensitizer. BOD1 is shown to accumulate in mitochondria, and cell viability is shown to decrease significantly with BOD1 compared to the loop end product, BOD2. Photoinduced enhancement of fluorescence indicates the formation of inactive BOD2 under cellular conditions, and enhanced fluorescence acts as a reporter for the activity of the photosensitizer. We present the first example of PDT autoinactivation, and such a feedback control mechanism would enable a decrease in post-therapy side effects., BAGEP Award of the Science Academy, This work was supported by the BAGEP Award of the Science Academy.

WOS: 000472685700112, PubMed: 31042560, In this study, iron magnetic nanoparticles capped with fluorescent calixarene derivatives (Fe3O4@Calix-2 and Fe3O4@Calix-3) were prepared in one-step using coprecipitation of Fe(II) and Fe(III) in basic solution. Different techniques were used to characterize the synthesized magnetic nanoparticles, such as Fourier Transform Infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and confocal microscopy. Candida rugosa was encapsulated on synthesized nanoparticles following sol-gel method. It has been observed that under the optimum conditions, the activity of encapsulated lipase (Fe3O4@Calix-2E) was 119 U/g of support which is 4.1 times more that of the encapsulated lipase without calix[4]arene derivative (Fe3O4@E). Comparative study show that the encapsulated lipase on nanoparticles has higher thermal and operational stability than encapsulated lipase without calix[4]arene derivative. Among these encapsulated lipase nanoparticles, Fe3O4@Calix-2 was capable of effectively catalyze hydrolysis of racemic Flurbiprofen methyl ester with high conversion of 49% and substrate enantiomeric excess (ees) of 85% at optimum pH and temperature. The efficiency of these nanoparticles was assessed by their reusability, for that after five consecutive operational uses these encapsulated lipase nanoparticles retained their conversion ratios up to 38% and 30% respectively, in the hydrolysis of (R,S)-Flurbiprofen methyl ester. The results showed that encapsulated lipases nanoparticle with calixarene moieties lead to increased activity, stability, reusability and enhanced stereoselectivity in kinetic resolution. (C) 2019 Elsevier B.V. All rights reserved., Scientific Research Foundation of Selcuk University, Konya, TurkeySelcuk University [15201094], We would like to thank the Scientific Research Foundation of Selcuk University, Konya, Turkey (BAP Project No. 15201094) for financial support of this work.

WOS: 000512481000041, Laponite D is known as a zwitterionic synthetic clay having disc-shaped with negatively charged top faces and positively charged lateral edges, which is photochemically inactive and used to increase catalytic active surfaces. Herein, photocatalytic hydrogen evolution over Laponite D, which known as low cost inorganic clay, is firstly reported in a system containing Eosin-Y (EY) and triethanolamine (TEOA) as a photosensitizer and electron donor, respectively, under visible light illumination. This reaction system shows excellent stability due to the good charge transport and separation efficiency thanks to zwitterionic property of Laponite D.

This paper reports the findings of a study describing the production of chitosan-based edible films incorporated with different amount of Pimpinella anisum seed oil. The chitosan-aniseed oil (CAO) composite films (CS, CAO-0.5, CAO-1, and CAO-2) were characterized with FT-IR and DSC and their mechanical, optical transmittance, hydrophobicity and anti-oxidative properties were also investigated. With the increasing concentration of aniseed oil in the films, a continuous decrease was observed in tensile strength and Young’s modulus. Optical transmittance of chitosan-aniseed oil composite films in the UV-Visible region was lower than that of chitosan control film (without aniseed oil). Incorporation of aniseed oil into chitosan films enhanced antioxidant activity of films. The results suggested that chitosan-aniseed oil composite films can be used as a food packaging material., Bu çalışma ile farklı miktarlarda Pimpinella anisum tohumu yağı katkılı kitosan temelli yenilebilir filmlerin üretimi yapılmıştır. Kitosan-anason tohumu yağı (CAO) katkılı kompozit filmler (CS, CAO-0.5, CAO-1 ve CAO-2) FT-IR ve DSC ile karakterize edilmiştir ve mekanik, optik geçirgenlik, hidrofobiklik ve anti-oksidan özellikleri araştırılmıştır. Filmlerin anason tohumu yağı miktarı arttıkça, gerilme mukavemeti ve Young modülünde düşüş gözlenmiştir. UV-Görünür bölgede kitosan-anason tohumu yağ kompozit filmlerin optik geçirgenliği, kitosan kontrol filme göre daha düşük olduğu görülmüştür. Anason tohumu yağının, kitosan filmlere katılması, filmlerin antioksidan aktivitesini arttırmıştır. Sonuçlar göz önüne alındığında, kitosan-anason tohumu yağı katkılı kompozit filmlerin, gıda ambalaj malzemesi olarak kullanılabilir bir malzeme olduğunu göstermektedir.

WOS: 000454537500021, PubMed: 30600000, This is the first study on production of three dimensional chitinous microcages from ephippial eggs of a microcrustacean, Daphnia longispina (water flea) by keeping the original shape of its chitinous structure. Iron-based magnetic particles were successfully loaded into the chitinous microcages to enhance its heavy metal sorption capacity. The FT-IR, SEM-EDX and TGA analysis proved the purity of chitin and demonstrated that the loading of magnetic particles into the chitinous microcages was achieved. These newly obtained three-dimensional chitin microcages and magnetic particles loaded microcages were tested in Cd(II), Cr(III), Cu(II), Ni(II) and Zn(II) removal from aqueous solutions. Magnetic particles loaded microcages exhibited a better performance in removal of Cd(II), Cu(II) and Ni(II) ions; while unloaded microcages showed a higher affinity for Cr(III) and Zn(II). This study demonstrated that the chitin microcages are suitable carriers for iron-based magnetic particles. Here these new materials were studied only for removal of five heavy metal ions but these promising materials have a potential to be used in various fields., Selcuk University Research Foundation, Turkey [BAP-14201082], This study was funded by Selcuk University Research Foundation, Turkey"(project number: BAP-14201082).

*Kaya, Murat ( Aksaray, Yazar ) *Baran, Talat ( Aksaray, Yazar ), We characterize the trunk cuticle of velvet worms of the Peripatoides novaezealandiae-group (Onychophora) using SEM, TEM, Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA). TEM and SEM revealed a relatively uniform organization of the delicate cuticle that is covered by numerous bristled and nonbristled papillae with ribbed scales arranged in transverse rows. The cuticle consists of a very thin multilayered epicuticle of varying appearance followed by the largely fibrous procuticle. The irregularly arranged nanofibres of isolated cuticular chitin seen by SEM are considered as bundles of chitin fibres. FT-IR and TGA showed that the chitin is of the α-type. This confirms and broadens the single previous study in which the presence of α-chitin in a velvet worm was demonstrated with a single analysis (X-ray diffraction).

WOS: 000466621200003, PubMed: 30731166, Modified chitin and magnetic particles are two important materials widely used in heavy metal removal studies. Loading of magnetic particles into conventional adsorbents has emerged as a recent convenient way to improve the properties of adsorptive materials. Compared to its deacetylated form chitosan, chitin has very limited use in removal of contaminants because of its insolubility in aqueous environments. This study reports an easy way to produce micro-sized chitin and gives details on loading of magnetic particles into micro-sized chitin to enhance the interaction of chitin with heavy metal contaminant; hexavalent chromium Cr(VI). Removal of Cr(VI) ions from the aquatic environments is of high importance considering its detrimental effects on human health. Chitin microcages that had been isolated from the ephippial eggs of Daphnia longispina (crustacean, water flea) were incorporated with magnetic particles. Chitin microcages and magnetic particles-loaded chitin microcages were tested in removal of Cr(VI) under different solution and operational parameters; adsorbent dosage, contact time, Cr(VI) ion concentration, pH and temperature. Magnetic particles-loaded chitin microcages yielded higher Cr(VI) removal performance under all the specified conditions; chitin microcages: 0.77 mmol/g and particles loaded chitin microcages: 1.29 mmol/g. (C) 2019 Elsevier B.V. All rights reserved.