Immobilization of catalase via adsorption onto -histidine grafted functional pHEMA based membrane

Poly(2-hydroxyethylmethacrylate) (pHEMA) based flat sheet membrane was prepared by UV-initiated photopolymerization technique. The membrane was then grafted with -histidine. Catalase immobilization onto the membrane from aqueous solutions containing different amounts of catalase at different pH was investigated in a batch system. The maximum catalase immobilization capacity of the pHEMA–histidine membrane was 86 μg cm⁻². The activity yield was decreased with the increase of the enzyme loading. It was observed that there was a significant change between V_max value of the free catalase and V_max value of the adsorbed catalase on the pHEMA–histidine membrane. The K_m value of the immobilized enzyme was higher 1.5 times than that of the free enzyme. Optimum operational temperature was 5°C higher than that of the free enzyme and was significantly broader. It was observed that enzyme could be repeatedly adsorbed and desorbed without loss of adsorption capacity or enzyme activity.     

Non-native fishes in the Mediterranean from the Red Sea,by way of the Suez Canal

The opening of the Suez Canal in 1869 caused a migration generally from the Red Sea to the Mediterranean, rarely the opposite direction, and 63 lessepsian fish species penetrated into the Mediterranean by way of this canal. These species usually spread northward and most of them can establish wide populations in this area, but some of them can not be successful with respect to establishment. Thus, it is clearly seen that there are a lot of factors influencing the success of species with respect to migration, spreading and establishment. So, the lessepsian migration has been formed by the effects of these factors. Lessepsian species also have the ability to adapt to the ecological conditions of their new environment. Therefore, the influential factors, their effectiveness and the observed changes in lessepsian species due to the effects of these factors have been discussed by considering fishes in this paper.     

AHNAK controls 53BP1-mediated p53 response by restraining 53BP1 oligomerization and phase separation

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Bilayer heterojunction solar cell based on naphthalene bis-benzimidazole

We have fabricated a bilayer heterojunction solar cell consisting of p-n active layers of naphthalenetetracarboxylic bis-benzimidazole, N-CON, and zinc phthalocyanine, ZnPc. Conjugated naphthalene derivative of naphthalene bis-benzimidazole was employed as an electron acceptor. Bilayer solar cells were produced by successive evaporation of zinc phthalocyanine, ZnPc, and naphthalene bis-benzimidazole, N-CON, on glass substrates coated with indium doped tin oxide, ITO/PEDOT:PSS/ZnPc/N-CON/Al. Photovoltaic characteristics of bilayer cell were measured under simulated AM 1.5 sun illumination (V_oc = 0.50 V, J_sc = 2.11 mA/cm², FF = 0.51, η = 0.54%). Efficiency of the cell was discussed in relation to energy gap and work functions of the thin layers.     

Relations between elevated temperatures and fermentation behaviour of Kloeckera apiculata and Saccharomyces cerevisiae associated with winemaking in mixed cultures

One of the important factors affecting wine fermentation is temperature. The influence of elevated temperatures from 10 to 25 °C at 5 °C intervals on yeast growth and fermentation products were studied in mixed cultures of Kloeckera apiculata and Saccharomyces cerevisiae in grape juice. In the experiments carried out at 10 and 15 °C, K. apiculata grew and survived longer compared to trials conducted above 20 °C. In most cases, higher temperatures stimulated the production of higher alcohols but lowered the formation of esters and acetaldehyde. This revised version was published online in July 2006 with corrections to the Cover Date.     

A new species of the genus Vulda Jacquelin du Val from Turkey (Coleoptera: Staphylinidae: Xantholinini)

Vulda assingi sp. n. from Bozda?lar, Manisa province, western Anatolia, is de-scribed, illustrated and distinguished from congeners recorded from Turkey. Additional records are reported for two species. A total of six species is now known from Turkey.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:B3E6C251-50D4-4985-9655-2EAC57869F18     

On the genus Sunius Curtis, 1829 of Turkey III. Four new species from western Anatolia,Turkey (Coleoptera: Staphylinidae: Paederinae)

Four new micropterous species of the genus Sunius Curtis, 1829 are described and illustrated from western Anatolia: Sunius akdaghensis sp. n. from Kütahya province, Sunius ciceki sp. n. from Bal?kesir province, Sunius ozgeni sp. n. and Sunius cagatayi sp. n. from Denizli province. Additional records are presented for three species. The genus Sunius is now represented in Turkey by 36 species.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:F3808D28-65E9-4619-A350-781C971701EC     

炎症性肠病与艰难梭菌感染相关性研究的文献计量学和可视化分析

【背景】近年来,炎症性肠病患者中艰难梭菌（Clostridium difficile）感染率逐年上升,受到国内外学者广泛关注。我国在该领域的研究起步较晚,但患者数量众多,学习国际上对于炎症性肠病合并艰难梭菌感染的研究,对推动我国在该领域的深入发展具有重要意义。【目的】通过文献计量和可视化分析帮助研究者把握炎症性肠病与艰难梭菌感染相关性研究中的研究主题、方向、热点与前沿。【方法】同时检索Web of Science （WOS）中Science Citation Index Expanded （SCI-E）和CNKI中收录的关于炎症性肠病和艰难梭菌的相关文献,应用CiteSpace 6.2.2r软件进行国家/地区、机构、作者、关键词共现及被引文献、期刊共被引分析,同时进行可视化分析。【结果】经过数据检索和查重,最终可供分析的文献为WOS数据库1 030篇、CNKI数据库80篇。全球范围内,发文最多的国家是美国,主要研究机构有Harvard University、University of California System和Mayo Clinic等,高产作者有Khanna S、Shen B和Ananthakrishnan AN等,高频关键词包括Inflammatory bowel disease、Ulcerative colitis、Clostridium difficile、Clostridium difficile infection和Crohn’s disease等,聚类方向有#0 Diarrhea、#1 Ulcerative colitis、#2 Probiotics、#3 Pouchitis、#4 Gut microbiota、#5 Fecal microbiota transplantation、#6 Depression、#7 Entamoeba histolytica、#8 Pseudomembranous colitis、#9 Clostridium difficile和#10 Clindamycin。国内主要研究机构有南方医科大学和河北医科大学,高产作者有王浦、王斯淇等,高频关键词包括粪菌移植、艰难梭菌、肠道菌群、危险因素和克罗恩病等,聚类方向有#0艰难梭菌、#1益生菌、#2危险因素、#3腹泻和#4粪菌移植。【结论】利用CiteSpace软件对炎症性肠病和艰难梭菌感染相关性研究进行计量及可视化分析可知,该方向仍得到全球各医疗机构及研究者的关注,腹泻及粪菌移植这两个关键词分别代表了WOS数据库和CNKI数据库关于炎症性肠病合并艰难梭菌感染研究的热点。     

Enzymatic pre‐treatment of microalgae cells for enhanced extraction of proteins

Crude proteins and pigments were extracted from different microalgae strains, both marine and freshwater. The effectiveness of enzymatic pre‐treatment prior to protein extraction was evaluated and compared to conventional techniques, including ultrasonication and high‐pressure water extraction. Enzymatic pre‐treatment was chosen as it could be carried out at mild shear conditions and does not subject the proteins to high temperatures, as with the ultrasonication approach. Using enzymatic pre‐treatment, the extracted proteins yields of all tested microalgae strains were approximately 0.7 mg per mg of dry cell weight. These values were comparable to those achieved using a commercial lytic kit. Ultrasonication was not very effective for proteins extraction from Chlorella sp., and the extracted proteins yields did not exceed 0.4 mg per mg of dry cell weight. For other strains, similar yields were achieved by both treatment methods. The time‐course effect of enzymatic incubation on the proteins extraction efficiency was more evident using laccase compared to lysozyme, which suggested that the former enzyme has a slower rate of cell disruption. The crude extracted proteins were fractionated using an ion exchange resin and were analyzed by the electrophoresis technique. They were further tested for their antioxidant activity, the highest of which was about 60% from Nannochloropsis sp. The total phenolic contents in the selected strains were also determined, with Chlorella sp. showing the highest content reaching 17 mg/g. Lysozyme was also found to enhance the extraction of pigments, with Chlorella sp. showing the highest pigments contents of 16.02, 4.59 and 5.22 mg/g of chlorophyll a, chlorophyll b and total carotenoids, respectively.