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991.
Lauris del Carmen Mejia-da-Silva Marcelo Chuei Matsudo Ana Lucia Morocho-Jacome João Carlos Monteiro de Carvalho 《Applied biochemistry and biotechnology》2018,186(1):40-53
Since cultivations of Arthrospira platensis have a high water demand, it is necessary to develop treatment methods for reusing the exhausted medium that may prevent environmental problems and obtaining useful biomass. The exhausted Schlösser medium obtained from A. platensis batch cultivation in bench-scale mini-tanks was treated by varying concentrations of different coagulants, ferric chloride (6, 10, and 14 mg L?1) or ferric sulfate (15, 25, and 35 mg L?1) and powdered activated carbon (PAC, 30 and 50 mg L?1). Such treated effluent was restored with NaNO3 and reused in new cultivations of A. platensis performed in Erlenmeyer flasks. Reusing media through the cultivation of A. platensis showed satisfactory results, particularly in the medium treated with ferric chloride and PAC. The maximum cell concentration obtained in the flasks was 1093 mg L?1, which corresponded to the medium treated with ferric chloride (6 mg L?1) and PAC (30 mg L?1). This cellular growth was higher than in the medium treated with ferric sulfate and PAC, in which values of maximum cell concentration did not exceed 796 mg L?1. The cultures in the media after treatment did not modify the biomass composition. Thus, combined coagulation/adsorption processes, commonly used in water treatment processes, can be efficient and viable for treating exhausted medium of A. platensis, allowing the production of such biomass with the reduction of production cost and saving water. 相似文献
992.
André Eliezer Polloni Viviane Chiaradia Eduardo Moresco Figura João Pedro De Paoli Débora de Oliveira J. Vladimir de Oliveira Pedro Henrique Hermes de Araujo Claudia Sayer 《Applied biochemistry and biotechnology》2018,184(2):659-672
The demand for environmentally friendly products allied with the depletion of natural resources has increased the search for sustainable materials in chemical and pharmaceutical industries. Polyesters are among the most widely used biodegradable polymers in biomedical applications. In this work, aliphatic polyesters (from globalide and ω-pentadecalactone) were synthesized using a new commercial biocatalyst, the low-cost immobilized NS 88011 lipase (lipase B from Candida antarctica immobilized on a hydrophobic support). Results were compared with those obtained under the same conditions using a traditional, but more expensive, commercial biocatalyst, Novozym 435 (lipase B from C. antarctica immobilized on Lewatit VP OC). When NS 88011 was used in the polymerization of globalide, longer reaction times (240 min)—when compared to Novozym 435—were required to obtain high yields (80–90 wt%). However, higher molecular weights were achieved. When poly(ω-pentadecalactone) was synthesized, high yields and molecular weights (130,000 g mol?1) were obtained and the enzyme concentration showed strong influence on the polyester properties. This is the first report describing NS 88011 in polymer synthesis. The use of this cheaper enzymatic preparation can provide an alternative for polyester synthesis via enzymatic ring-opening polymerization. 相似文献
993.
Marimuthu Senthilkumaran Ramesh Kumar Chitumalla Ganesan Vigneshkumar Eswaran Rajkumar Paulpandian Muthu Mareeswaran Joonkyung Jang 《Journal of inclusion phenomena and macrocyclic chemistry》2018,91(3-4):161-169
The interaction of 2,4,6-triphenylpyrylium cation with p-sulfonatocalix[4]arene is studied using absorption, emission, NMR and electrochemical techniques. The increase in the absorption is observed with the increase in the concentration of p-sulfonatocalix[4]arene. The emission intensity of 2,4,6-triphenylpyrylium cation is also enhanced in the presence of p-sulfonatocalix[4]arene. The electrochemical titration reveals the presence of host–guest interaction. The NMR analysis explains the upper rim interaction of 2,4,6-triphenypyrylium cation with p-sulfonatocalix[4]arene. The mode of binding is studied using computational methods. The quantum chemical simulations reveal the binding orientation of cationic TPP with p-SC4. The calculated complexation energy (??33.19 kcal mol?1) indicates the strong binding nature of 2,4,6-triphenylpyrylium cation with p-sulfonatocalix[4]arene. 相似文献
994.
Ribicki Ariane Caroline Chemin Bianca Gurski Van Haandel Viviane Jandira Winiarski João Paulo de Castro Rozada Thiago Pessoa Christiana Andrade Estrada Ruben Auccaise Fiorin Barbara Celânia Fujiwara Sérgio Toshio 《Journal of Sol-Gel Science and Technology》2018,87(1):216-229
Journal of Sol-Gel Science and Technology - A silsesquioxane based on a silica matrix and 4-(aminomethyl)pyridine group was successfully synthesized using the sol–gel process with the... 相似文献
995.
Christina C Roggatz Mercedes González-Wangüemert Hugo Pereira Catarina Vizetto-Duarte Maria João Rodrigues Luísa Barreira 《Natural product research》2018,32(1):116-120
This work reports for the first time the nutritional profile, including proximate chemical composition, amino acids, fatty acids and minerals of Parastichopus regalis from the Mediterranean Sea (SE Spain). The studied species had a high moisture content, moderate protein and low lipid levels. The most abundant amino acids were glutamic acid, arginine and tyrosine. Polyunsaturated fatty acids, especially arachidonic acid, dominated the fatty acid profile. Iron, sodium, calcium and zinc were the most abundant mine rals. In general, P. regalis has a balanced nutritional quality suitable for human consumption. 相似文献
996.
Le Ba Vinh Nguyen Thi Minh Nguyet Seo Young Yang Jang Hoon Kim Le Thi Vien Phan Thi Thanh Huong 《Natural product research》2018,32(17):2001-2007
Eight compounds were isolated from the leaves of Clerodendrum inerme, including one new rearranged abietane diterpene, crolerodendrum B (1). Their structures were determined by means of spectroscopic methods including one-dimensional and two-dimensional nuclear magnetic resonance (1-D and 2-DNMR), high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS) and circular dichroism (CD). The DPPH radical scavenging and cytotoxic activities of isolated compounds against MCF7 (breast), HCT116 (colon) and B16F10 (melanoma) cancer cell lines were evaluated. Compounds 1, 3 and 4 exhibited strong DPPH radical-scavenging effects (ED50 values of 17.6 ± 2.1, 10.1 ± 0.8 and 11.3 ± 0.3 μM, respectively) and 4 showed strong cytotoxicity against the HCT116 cell line (IC50 = 3.46 ± 0.01 μM). 相似文献
997.
1,4‐Iron Migration for Expedient Allene Annulations through Iron‐Catalyzed C−H/N−H/C−O/C−H Functionalizations
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Jiayu Mo Thomas Müller Dr. João C. A. Oliveira Prof. Dr. Lutz Ackermann 《Angewandte Chemie (International ed. in English)》2018,57(26):7719-7723
C?H activation bears great potential for enabling sustainable molecular syntheses in a step‐ and atom‐economical manner, with major advances having been realized with precious 4d and 5d transition metals. In contrast, we employed earth abundant, nontoxic iron catalysts for versatile allene annulations through a unique C?H/N?H/C?O/C?H functionalization sequence. The powerful iron catalysis occurred under external‐oxidant‐free conditions even at room temperature, while detailed mechanistic studies revealed an unprecedented 1,4‐iron migration regime for facile C?H activations. 相似文献
998.
Two Aluminophosphate Molecular Sieves Built from Pairs of Enantiomeric Structural Building Units
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Seungwan Seo Taimin Yang Dr. Jiho Shin Dr. Donghui Jo Prof. Xiaodong Zou Prof. Suk Bong Hong 《Angewandte Chemie (International ed. in English)》2018,57(14):3727-3732
Herein we report the synthesis and structures of two new small‐pore aluminophosphate molecular sieves PST‐13 and PST‐14 with mutually connected 8‐ring channels. The structure of PST‐13, synthesized using diethylamine as an organic structure‐directing agent, contains penta‐coordinated framework Al atoms bridged by hydroxy groups and thus edge‐sharing 3‐ and 5‐rings. Upon calcination, PST‐13 undergoes a transformation to PST‐14 with loss of bridging hydroxy groups and occluded organic species. The structures of both materials consist “nonjointly” of pairs of previously undiscovered 1,5‐ and 1,6‐open double 4‐rings (d4rs) which are mirror images of each other. We also present a series of novel chemically feasible hypothetical structures built from 1‐open d4r (sti) or 1,3‐open d4r (nsc) units, as well as from these two enantiomeric structural building units. 相似文献
999.
Insub Jung Haneul Yoo Dr. Hee‐Jeong Jang Dr. Sanghyun Cho Kyungeun Lee Prof. Dr. Seunghun Hong Prof. Dr. Sungho Park 《Angewandte Chemie (International ed. in English)》2018,57(7):1841-1845
An unprecedented active and dynamic sensing platform based on a LSPR configuration that is modulated by using an external magnetic field is reported. Electrochemically synthesized Au/Fe/Au nanorods exhibited plasmonically active behavior through plasmonic coupling, and the middle ferromagnetic Fe block responded to a magnetic impetus, allowing the nanorods to be modulated. The shear force variation induced by the specific binding events between antigens and antibodies on the nanorod surface is used to enhance the sensitivity of detection of antigens in the plasmonics‐based sensor application. As a proof‐of‐concept, influenza A virus (HA1) was used as a target protein. The limit of detection was enhanced by two orders of magnitude compared to that of traditional LSPR sensing. 相似文献
1000.
Brereton Richard G. Jansen Jeroen Lopes João Marini Federico Pomerantsev Alexey Rodionova Oxana Roger Jean Michel Walczak Beata Tauler Romà 《Analytical and bioanalytical chemistry》2018,410(26):6691-6704
Analytical and Bioanalytical Chemistry - The contribution of chemometrics to important stages throughout the entire analytical process such as experimental design, sampling, and explorative data... 相似文献