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comparative study of polyhydroxyalkanoates production from acidified and anaerobically treated brewery wastewater using enriched mixed microbial culture

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Journal of Environmental Sciences 2019年第4期31卷 137-146页

作者： Pravesh Tamang Rintu Banerjee Stephan K?ster regina nogueira Institute for Sanitary Engineering and Waste Management Leibniz Universitat Hannover Welfengarten 1D-30167 HannoverGermany Indian Institute of Technology Kharagpur Department of Agricultural and Food Engineering721302 KharagpurIndia

The production of polyhydroxyalkanoates(PHA) from wastewaters using microbial mixed cultures(MMc) has been attracting increased interest because of PHA's biodegradability characteristics. Production of PHA by an MMc enriched with PHA-accumulating bacteria was compared using anaerobically treated and acidified brewery wastewaters under various feeding strategies, namely pulse and batch feed addition. To obtain an enriched MMc, a sequencing batch reactor was inoculated with activated sludge fed with acetate and subjected to aerobic dynamic feeding. The enriched MMc was able to accumulate PHA up to 72.6% of cell dry weight(cDW) with pulse addition of acetate controlled by the dissolved oxygen(DO) concentration in the reactor. In a batch accumulation experiment with acetate,the PHA content achieved(28.5% cDW) was less than that of the pulse feeding strategy with the same amount of acetate(～2000 mg c/L). Using anaerobically treated and acidified brewery wastewater fed in pulses, the maximum PHA accumulated by the enriched MMc was similar for both wastewaters(45% cDW), in spite of the higher volatile fatty acid concentration in acidified brewery wastewater. The pulse feed addition controlled by the DO concentration was difficult to implement for wastewater as compared to acetate because the difference in DO concentration between substrate availability and depletion was low. For the batch addition of acidified wastewater, a slightly lower PHA content(39%cDW) was obtained. These results show that both brewery wastewaters can be utilized for PHA production with a similar maximum PHA storage capacity.

关键词： Polyhydroxyalkanoates PHA-accumulating bacteria Microbial mixed culture Brewery wastewater Aerobic dynamic feeding Pulse feeding and batch feeding

The Use of Solid State NMR to Evaluate the carbohydrates in commercial coffee Granules

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Food and Nutrition Sciences 2011年第4期2卷 350-355页

作者： regina Freitas nogueira Elisangela Fabiana Boffo Maria Inês Bruno Tavares Leonardo AMoreira Leila Aley Tavares Antonio Gilberto Ferreira Departamento de Química da Universidade Federal de Sao CarlosSao CarlosBrasil Institutito de Macromoléculas Universidade Federal do Rio de JaneiroRio de JaneiroBrasil Escola Técnica Federal de Minas GeraisBrasil

coffee brings many health benefits due to its chemical constituents. Based on this information, it is essential to know the main chemical compounds from coffee granules;the intermolecular interaction among the coffees compounds and the molecular components homogeneity. In this study six types of roasted commercial coffee were evaluated by solid state nuclear magnetic resonance (NMR), employing carbon-13 (13c) and hydrogen (1H) nucleus. carbon-13 was analyzed applying high field NMR techniques, such as: magic angle spinning (MAS);magic angle spinning with cross-polariza- tion (cPMAS) and magic angle spinning with cross-polarization and dipolar dephasing (cPMASDD). The hydrogen was evaluated via relaxation times. Proton spin-lattice relaxation time in the rotating frame was deter-mined through the carbon-13 decay, during the variable contact-time experiment, using high field NMR. Proton spin-lattice relaxation time was determined through the inversion-recovery pulse sequence, using low field NMR. considering all NMR results, it was concluded that the major coffee compounds are: a) triacilglycerides, which constitute the mobile region in the granule coffee and b) carbohydrates such as: polysaccharides and fibers that belong to the rigid domain. These constituents belong to different molecular mobility domain, although they have strong intermolecular interactions due to the granule organization.

关键词： Solid State NMR coffee

The Evaluation of Polyethylene/clay composite from Solid State NMR

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Materials Sciences and Applications 2011年第5期2卷 453-457页

作者： regina F.nogueira Maria Ines B.Tavares Rosane A.S.San Gil Antonio G.Ferreira Departamento de Quimica Universidade Federal de Sao CarlosSao CarlosBrasil Laboratorio de Nanocompositos Polimericos Instituto de Macromoleculas Professora Eloisa Mano da Universidade Federal do Rio de JaneiroRio de JaneiroBrasil Departamento de Quimica Organica da Universidade Federal do Rio de JaneiroRio de JaneiroBrasil

Polymeric nanocomposites based on polyethylene (PE) and Brazilian natural montmorillonite clay (MN) were obtained by melt processing, using a twin-screw extruder. The main objective of this work is focusing on the characterization of composites materials by solid-state nuclear magnetic resonance (NMR). The solid-state NMR measurements were used to observe both polymer matrix (through carbon-13 and hydrogen nuclei) and the clay (silicon-29 and aluminum-27). The polymer matrix analyses were carried out applying solid state techniques, such as: cross-polarization magic angle spinning (cPMAS), variable contact time (VcT) and by the proton spin-lattice relaxation time in the rotating frame parameter (T1ρH), detected from the resolved carbon-13 decay of the VcT experiment and through the determination of spin-lattice relaxation time, T1H (using low field NMR). The clay was analyzed by 29Si and 27Al, employing MAS NMR technique. From those techniques we can have principally response on clay dispersion in the polyethylene matrix, as well as the interactions between both components in the nanostructured material. The T1H response was an important result which showed, that the materials formed, presented different molecular domains (according to the domain size that varied from 25 to 50 nm, measured by relaxation), considering the clay dispersion mode in terms of intercalation and/or exfoliation in the polymer matrix.

关键词： NMR Polymer Polyethylene clay Montmorillonite

Alterations in Low-Z Elements Distribution in Heart Tissue after Treatments to Breast cancer Using LEXRF Technique

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American Journal of Analytical chemistry 2016年第11期7卷 754-771页

作者： Andrea Mantuano regina cely Barroso Liebert Parreiras nogueira Marcos Vinicius colaço carla Lemos Mota Arissa Pickler Delson Braz camila Salata Samara Ferreira-Machado carlos Eduardo de Almeida Alessandra Gianoncelli Physics Institute Rio de Janeiro State University Rio de Janeiro Brazil Nuclear Engineering Program Federal University of Rio de Janeiro Rio de Janeiro Brazil Radiological Science Laboratory State University of Rio de Janeiro Rio de Janeiro Brazil Elettra-Sincrotrone Trieste S.c.p.a. Trieste Italy

Data from Global cancer Statistics show that breast cancer (Bc) is the most common type of cancer among women, leading the number of deaths caused by cancer. The developments in diagnosis and treatment techniques for the Bc, including chemotherapy and/or radiotherapy, increased the survival rates for this type of cancer. One late complication induced by Bc treatment is the cardiotoxicity. This term comprises different cardiotoxic side effects, which include blood pressure alterations, myocardial ischemia, congestive heart failure and other damages. This study aimed to evaluate the cardiac alterations induced by radiotherapy and chemotherapy, simulating a treatment for Bc in Wistar rats. It is, therefore, important to understand the mechanisms involved in the cardiotoxicity, in order to prevent women from this late effect, when they undergo Bc treatments. The major interests in this work are in Low atomic weight elements as Sodium, because it is strongly related to cardiomyocyte contraction;Magnesium, because it is important in the cardiac metabolism;and Iron, because Bc treatment induced cardiotoxicity can be associated to the oxidative stress. changes that occur in unhealthy tissues in case to cardiovascular damages can be better understood when elemental compounds and structures of healthy tissues are known. Low Energy X-ray Fluorescence (LEXRF) technique was used to obtain elemental maps of low Z-elements providing a semi-quantitative analysis of the tissues evaluated under different conditions. Through the technique LEXRF we obtained elemental and absorption maps. The results showed more damages when associating chemotherapy and radiotherapy in comparison to myocardium healthy. Those images taken together with light microscopy, X-ray absorption and phase contrast images, satisfactorily characterize the cardiac tissue for the first time in the literature, from the structural and morphological points of view. LEXRF was carried out at TwinMic beamline in the ELETTR

关键词： Micro-X-Ray Fluorescence Low-Z Elements Distribution Myocardial cardiac Tissue

The Evaluation of Polyethylene/clay composite from Solid State NMR

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