Terpanos pentacíclicos como indicadores de heterogeneidades composicionais em reservatório de petróleo biodegradado

Reservoir geochemistry has been effectively used to evaluate compositional heterogeneity in petroleum reservoirs by employing oil fingerprinting technique to assess reservoir continuity, primarily in paraffin oil accumulations. In-reservoir biodegradation has resulted in vast deposits of heavy oils globally; therefore, the application of reservoir geochemistry to such accumulations becomes necessary. We recommend the use of pentacyclic terpanes instead of lower molecular compounds, which are less resistant to biodegradation. Using oil fingerprinting technique in this novel way enabled the differentiation of oil composition among sedimentary facies of tar sands (Pirambóia Formation, Paraná Basin).

Biodegradação bacteriana de compostos organoclorados

Due to their recalcitrant nature, organochlorides are already found in environment and the search for alternatives to eliminate these compounds such as biodegradation using native microorganisms is of great interest. A screening trial to select environmental bacteria able to degrade DDD, PCP and dieldrin was conducted. Among 14 isolates, the soil bacteria Pseudomonas aeruginosa L2-1 showed the highest tolerance to increasing concentrations of the organochlorides and was selected for further studies. Biodegradation was assessed in liquid medium, varying the concentrations of glucose and the presence of rhamnolipids (RL). The best medium for the occurrence of biodegradation of the compounds contained 0.5% glucose, giving approximately 50% yield after three days of incubation. Results showed that the biodegradation rates of the organochlorides by P. aeruginosa L2-1 were greater at low concentrations of glucose and in the presence of rhamnolipids.

DEGRADAÇÃO MICROBIOLÓGICA E ENZIMÁTICA DE POLÍMEROS: UMA REVISÃO

Polymer recycling has been one of the most important trend in the petrochemical area. Among different technologies, biotechnological (enzymatic and/or microbial) degradation of polymers for the recovery of monomers and oligomers is environmentally-friendly and meet some green chemistry principles. In this work, conditions for the biotechnological degradation of some industrially-relevant polymers (e.g. poly(ethylene terephthalate) and polyethylene) were revised, and the main biocatalysts were identified. In most cases, biodegradation mechanisms are still unclear, thus being necessary more studies to unravel these promising bioprocesses. Polymer biodegradation studies also present considerable importance for other fields, including biomedical and agricultural.

Selection of microorganisms producer of lipase for fat removal from biodiesel purification water

The objective this study has been the selection of lipase productor microorganism, for removal of oils and grease, in the pre-treatment of biodiesel wastewater washing. For this, analyses of the physicist-chemistries characteristics had been made with the wastewater of the biodiesel washing, and then it had been isolated and chosen, by means of determinations of the lipase activity. Following, it was made a test of fat biodegradation, in the conditions: pH (5.95), temperature (35 ºC), rotation (180 rpm) and ammonium sulfate as nitrogen source (3 g L-1) and establishing as variable the two microorganism preselected and the time (24; 48; 72; 96 and 120 h). The biodiesel purification wastewater had presented high potential of environmental impact, presenting a concentration of O of 6.76 g L-1. From the six isolated microbiological cultures, two microorganisms (A and B) had been selected, with enzymatic index of 0.56 and 0.57, respectively. The treatment of the wastewater using the isolated microorganism (Klebsiella oxytoca) had 80% of the fatty removal in 48 h.

Ammonia nitrogen desorption from sanitary landfill leachate in filling towers

Sanitary landfill leachates present high concentrations of carbonaceous and nitrogenous materials. The crucial point is that carbonaceous materials are of difficult biodegradation, what compromises the performance of biological treatment processes, while nitrogenous materials, such as ammonia nitrogen, probably preclude the use of biological treatments. Therefore, the aim of this work was to study the desorption process of ammonia nitrogen from sanitary landfill leachate in filling towers. Desorption was carried out in filling towers of 35 L capacity. The leachate was collected from a sanitary landfill located in João Pessoa, Paraíba State, Brazil. Desorption efficiency for the pH values ​​adopted in four treatments was 93% minimum and 95.5% maximum, with aeration mean time ranging from 3 to 6 hours. The limiting factors of ammonia nitrogen desorption from sanitary landfill leachates in filling towers are associated with the use of alkalizer species for pH correction, and electricity costs for aeration.

Biodegradable packaging materials in 2013 and their feasibility in chocolate industry

The development of biopolymers has been rapid in recent years and the range of available bioplastics is increasing continuously, driven by a growing demand for sustainable solutions. There are several key drivers behind this growth. The oil reservoirs are decreasing which is causing a price increase for the traditional plastic materials and therefore the gap to bioplastics’ price is getting smaller. In addition, other environmental topics, such as waste disposal and green production, have become more and more important factors for institutes, companies and consumers. Legislation and directives have to be taken into account as well in decision making concerning different packaging materials. The new environmental law with waste disposal responsibility will also have an effect on the packaging business. Therefore a need has risen to study closer the current offering closer of bio-based materials that could be used in chocolate packaging. In this Master’s Thesis the bioplastics’, and especially biodegradable materials’ technical properties and their development, availability, possible existing products in the markets, waste disposal possibilities and consumers attitude towards environmental friendly packaging is studied. This is a case study where the offering of biodegradable materials was investigated during March 2013 for Fazer Confectionary.

Genetic engineering of baker's and wine yeasts using formaldehyde hyperresistance-mediating plasmids

Yeast multi-copy vectors carrying the formaldehyde-resistance marker gene SFA have proved to be a valuable tool for research on industrially used strains of Saccharomyces cerevisiae. The genetics of these strains is often poorly understood, and for various reasons it is not possible to simply subject these strains to protocols of genetic engineering that have been established for laboratory strains of S. cerevisiae. We tested our vectors and protocols using 10 randomly picked baker's and wine yeasts all of which could be transformed by a simple protocol with vectors conferring hyperresistance to formaldehyde. The application of formaldehyde as a selecting agent also offers the advantage of its biodegradation to CO2 during fermentation, i.e., the selecting agent will be consumed and therefore its removal during down-stream processing is not necessary. Thus, this vector provides an expression system which is simple to apply and inexpensive to use

The effect of moisture on decomposition processes in the disturbed peatlands of the Wainfleet bog /

The purpose of this study was to determine the effect of increased soil moisture levels on the decomposition processes in a peat-extracted bog. Field experiments, in which soil moisture levels were manipulated, were conducted using 320 microcosms in the Wainfleet Bog from May 2002 to November 2004. Decomposition was measured using litter bags and monitoring the abundance of macro invertebrate decomposers known as Collembola. Litter bags containing wooden toothpicks (n=2240), filter paper (n=480) and Betula pendula leaves (n=40) were buried in the soil and removed at regular time intervals up to one year. The results of the litter bag studies demonstrated a significant reduction of the decomposition of toothpicks (p<0.001), filter paper (p<0.001), and Betula pendula leaves (p

Encapsulation de Dehalococcoides: avantage pour la déhalogénation des solvants chlorés en sites contaminés

Le tétrachloroéthène (PCE) et les éthènes chlorés qui lui sont apparentés ont été abondamment utilisés pour plusieurs applications en industrie dès le début du 20e siècle. Ils sont cependant comptés parmi les polluants les plus communs des sols et de l’eau et beaucoup d’efforts sont déployés afin de les éliminer. Nous croyons que la conversion des éthènes chlorés en éthènes par des microorganismes est une solution prometteuse. Le premier aspect du projet visait donc à établir les conditions pour lesquelles un consortium enrichi en Dehalococcoides ethenogenes permettrait la conversion complète de PCE en éthène. Les expériences réalisées nous ont permis de souligner le rôle de l’acide lactique ajouté aux cultures comme source de carbone et source indirecte d’électrons pour la déhalorespiration. Nous avons également pu établir l’effet de la concentration initiale de biomasse dans les cultures sur le profil de déhalogénation du PCE. Le deuxième aspect du projet visait à développer un protocole d’encapsulation du consortium dans une matrice polymérique afin de profiter des nombreux avantages potentiels de l’encapsulation. Nous avons testé trois montages d’encapsulation différents : atomisation avec jet d’air, atomisation avec vibrations ultrasoniques et « drop-wise ». Le dernier montage prévoyait l’encapsulation des cultures dans des billes d’alginate enrobées de chitosane gélifié par du lignosulfonate. C’est le seul montage qui nous a permis d’encapsuler le consortium de façon efficace sans effet significatifs négatifs sur son activité de déchlorination. Aussi, la comparaison des profils de déhalogénation du PCE de cellules encapsulées et cellules libres a montré une plus faible accumulation de TCE, 1,2-DCE et VC dans les échantillons de cellules encapsulée et, par conséquent, une conversion plus rapide et plus complète du PCE en éthène. Finalement, nous avons observé une tendance favorable à l’idée que les microorganismes encapsulés bénéficient d’un effet de protection contre de faibles concentrations d’oxygène.

Ionomer Compatibilized Low Density Polyethylene - Tapioca Starch Blends Biodegradability and Photodegradability

Biodegradation is the chemical degradation of materials brought about by the action of naturally occurring microorganisms. Biodegradation is a relatively rapid process under suitable conditions of moisture, temperature and oxygen availability. The logic behind blending biopolymers such as starch with inert polymers like polyethylene is that if the biopolymer component is present in sufficient amount, and if it is removed by microorganisms in the waste disposal environment, then the base inert plastic should slowly degrade and disappear. The present work focuses on the preparation of biodegradable and photodegradable blends based on low density polyethylene incorporating small quantities of ionomers as compatibilizers. The thesis consists of eight chapters. The first chapter presents an introduction to the present research work and literature survey. The details of the materials used and the experimental procedures undertaken for the study are described in the second chapter. Preparation and characterization of low density polyethylene (LDPE)-biopolymer (starch/dextrin) blends are described in the third chapter. The result of investigations on the effect of polyethylene-co-methacrylic acid ionomers on the compatibility of LDPE and starch are reported in chapter 4. Chapter 5 has been divided into two parts. The first part deals with the effect of metal oxides on the photodegradation of LDPE. The second part describes the function of metal stearates on the photodegradation of LDPE. The results of the investigations on the role of various metal oxides as pro-oxidants on the degradation of ionomer compatibilized LDPE-starch blends are reported in chapter 6. Chapter 7 deals with the results of investigations on the role of various metal stearates as pro-oxidants on the degradation of ionomer compatibilized LDPE-starch blends. The conclusion of the investigations is presented in the last chapter of the thesis.

Bioremediation of Hydrocarbons by Lysinibacillus fusiformis BTTS10

There exists a need for potential microorganism that could facilitate effective bioremediation of crude oil pollutants in the environment. Hence it was desired to isolate a potential bacterium from marine sediment, which often experiences oil pollution and develop a bioprocess for crude oil biodegradation. In the present study the sediment deposits in the beach of Munakkal, Trichur dist, Kerala, collected immediately after the major event Tsunami in 2004 was collected and analyzed by enrichment culture technique towards isolation of potential strains that could degrade crude oil and its fractions. From the results obtained it was found that the sediment deposits harbor several bacteria with potential for degrading hydrocarbons. However, among the strains obtained, isolate no. BTTS 10 showed capabilities for utilizing both alkanes and aromatic hydrocarbons and hence the same was selected for further studies.

“Studies on extracellular enzyme production during growth of Pleurotus sp. on lignocellulosic agriwaste and the utilization of spent mushroom substrate”

Commercially, Pleurotus spp. of mushroom are cultivated in bags. After mushroom cultivation, spent substrate remains as residual material. Proper recycling of spent substrate is beneficial for our economy. Spent substrate can be utilized for various other value added purposes through the proper knowledge of its components. Composition of various components depends on the activity of extracellular enzymes in the spent substrate. The present study was conducted to know the enzyme profile of some major extracellular enzymes - cellulase, hemicellulase (xylanase), pectinase and ligninase (lignin peroxidase and laccase) and to estimate cellulose, hemicellulose, pectin and lignin in the substrate. The use of spent substrate as a source of fibre and ethanol, and in the biodegradation of phenol by Pleurotus spp. was also investigated

Diversity and effectiveness of tropical mangrove soil microflora on the degradation of polythene carry bags

The diversity and load of heterotrophic bacteria and fungi associated with the mangrove soil from Suva, Fiji Islands, was determined by using the plate count method. The ability of the bacterial isolates to produce various hydrolytic enzymes such as amylase, gelatinase and lipase were determined using the plate assay. The heterotrophic bacterial load was considerably higher than the fungal load. There was a predominance of the gram positive genus, Bacillus. Other genera encountered included Staphylococcus, Micrococcus, Listeria and Vibrio. Their effectiveness on the degradation of commercial polythene carry bags made of high density polyethylene (HDPE) and low density polyethylene (LDPE) was studied over a period of eight weeks in the laboratory. Biodegradation was measured in terms of mean weight loss, which was nearly 5 % after a period of eight weeks. There was a significant increase in the bacterial load of the soil attached to class 2 (HDPE) polythene. After eight weeks of submergence in mangrove soil, soil attached to class 1 and class 3 polythene mostly had Bacillus (Staphylococcus predominated in class 2 polythene). While most of the isolates were capable of producing hydrolytic enzymes such as amylase and gelatinase, lipolytic activity was low. Class 2 HDPE suffered the greatest biodegradation.

Molecular characterization of the nitrifying bacterial consortia employed for the activation of bioreactors used in brackish and marine aquaculture systems

The addition of commercial nitrifying bacterial products has resulted in significant improvement of nitrification efficiency in recirculating aquaculture systems (RAS). We developed two nitrifying bacterial consortia (NBC) from marine and brackish water as start up cultures for immobilizing commercialized nitrifying bioreactors for RAS. In the present study, the community compositions of the NBC were analyzed by universal 16S rRNA gene and bacterial amoA gene sequencing and fluorescence in situ hybridization (FISH). This study demonstrated that both the consortia involved autotrophic nitrifiers, denitrifiers as well as heterotrophs. Abundant taxa of the brackish water heterotrophic bacterial isolates were Paenibacillus and Beijerinckia spp. whereas in the marine consortia they were Flavobacterium, Cytophaga and Gramella species. The bacterial amoA clones were clustered together with high similarity to Nitrosomonas sp. and uncultured beta Proteobacteria. FISH analysis detected ammonia oxidizers belonging to b subclass of proteobacteria and Nitrosospira sp. in both the consortia, and Nitrosococcus mobilis lineage only in the brackish water consortium and the halophilic Nitrosomonas sp. only in the marine consortium. However, nitrite oxidizers, Nitrobacter sp. and phylum Nitrospira were detected in both the consortia. The metabolites from nitrifiers might have been used by heterotrophs as carbon and energy sources making the consortia a stable biofilm.