Extracts of Strawberry Fruits Induce Intrinsic Pathway of Apoptosis in Breast Cancer Cells and Inhibits Tumor Progression in Mice

Background: The consumption of berry fruits, including strawberries, has been suggested to have beneficial effects against oxidative stress mediated diseases. Berries contain multiple phenolic compounds and secondary metabolites that contribute to their biological properties. Methodology/Principal Findings: Current study investigates the anticancer activity of the methanolic extract of strawberry (MESB) fruits in leukaemia (CEM) and breast cancer (T47D) cell lines ex vivo, and its cancer therapeutic and chemopreventive potential in mice models. Results of MTT, trypan blue and LDH assays suggested that MESB can induce cytotoxicity in cancer cells, irrespective of origin, in a concentration-and time-dependent manner. Treatment of mice bearing breast adenocarcinoma with MESB blocked the proliferation of tumor cells in a time-dependent manner and resulted in extended life span. Histological and immunohistochemical studies suggest that MESB treatment affected tumor cell proliferation by activating apoptosis and did not result in any side effects. Finally, we show that MESB can induce intrinsic pathway of apoptosis by activating p73 in breast cancer cells, when tumor suppressor gene p53 is mutated. Conclusions/Significance: The present study reveals that strawberry fruits possess both cancer preventive and therapeutic values and we discuss the mechanism by which it is achieved.

Chemistry of secondary organic aerosol

The photooxidation of volatile organic compounds (VOCs) in the atmosphere can lead to the formation of secondary organic aerosol (SOA), a major component of fine particulate matter. Improvements to air quality require insight into the many reactive intermediates that lead to SOA formation, of which only a small fraction have been measured at the molecular level. This thesis describes the chemistry of secondary organic aerosol (SOA) formation from several atmospherically relevant hydrocarbon precursors. Photooxidation experiments of methoxyphenol and phenolic compounds and C₁₂ alkanes were conducted in the Caltech Environmental Chamber. These experiments include the first photooxidation studies of these precursors run under sufficiently low NO_x levels, such that RO₂ + HO₂ chemistry dominates, an important chemical regime in the atmosphere. Using online Chemical Ionization Mass Spectrometery (CIMS), key gas-phase intermediates that lead to SOA formation in these systems were identified. With complementary particle-phase analyses, chemical mechanisms elucidating the SOA formation from these compounds are proposed.

Three methoxyphenol species (phenol, guaiacol, and syringol) were studied to model potential photooxidation schemes of biomass burning intermediates. SOA yields (ratio of mass of SOA formed to mass of primary organic reacted) exceeding 25% are observed. Aerosol growth is rapid and linear with the organic conversion, consistent with the formation of essentially non-volatile products. Gas and aerosol-phase oxidation products from the guaiacol system show that the chemical mechanism consists of highly oxidized aromatic species in the particle phase. Syringol SOA yields are lower than that of phenol and guaiacol, likely due to unique chemistry dependent on methoxy group position.

The photooxidation of several C₁₂ alkanes of varying structure n-dodecane, 2-methylundecane, cyclododecane, and hexylcyclohexane) were run under extended OH exposure to investigate the effect of molecular structure on SOA yields and photochemical aging. Peroxyhemiacetal formation from the reactions of several multifunctional hydroperoxides and aldehyde intermediates was found to be central to organic growth in all systems, and SOA yields increased with cyclic character of the starting hydrocarbon. All of these studies provide direction for future experiments and modeling in order to lessen outstanding discrepancies between predicted and measured SOA.

TRANSFER OF ANALYTICAL METHODS FOR THE CHARACTERISATION OF NATURAL PRODUCTS TO R&D PROCESSES OF IDOKI

IDOKI SCF Technologies S.L. is a technology-based company, set up on September 2006 in Derio (Biscay) with the main scope of developing extraction and purification processes based on the use of supercritical fluid extraction technology (SFE) in food processing, extraction of natural products and the production of personal care products. IDOKI¿s researchers have been working on many different R&D projects so far, most of them using this technology. However, the optimization of a SFE method for the different matrices cannot be performed unless we have an analytical method for the characterisation of the extracts obtained in each experiment. The analytical methods are also essential for the quality control of the raw materials that are going to be used and also for the final product. This PhD thesis was born to tackle this problem and therefore, it is based on the development of different analytical methods for the characterisation of the extracts and products. The projects that we could include in this thesis were the following: the extraction propolis, the recovery of agroindustrial residues (soy and wine) and the dealcoholisation of wine.On the one hand, for the extraction of propolis, several UV-Vis spectroscopic methods were used in order to measure the antioxidant capacity and the total polyphenol and flavonoid content of the extracts. A SFC method was also developed in order to measure more specific phenolic compounds. On the other hand, for the recovery of agroindustrial residues UV-Vis spectroscopy was used to determine the total polyphenol content and two SFC methods were developed to analyse different phenolic compounds. Extraction methods such as MAE, FUSE and rotary agitation were also evaluated for the characterisation of the raw materials.Finally, for the dealcoholisation of wine, the development of a SBSE-TD-GC-MS and DHS-TD-GC-MS methods for the analysis of aromas and a NIR spectroscopic method for the determination of ethanol content with the help of chemometrics was necessary. Most of these methods are typically used in IDOKI¿s lab as routine analyses apart from others not included in this PhD thesis.

Investigation of taste tainting in salmon flesh in the Ribble catchment

This report presents the findings of the first phase of an investigation into the cause(s) of taints in salmonid fish in the River Ribble, commissioned by the North West Region of the Environment Agency. There have been reports of tainting in fish taken from both the estuary and the freshwater river for many years, but the contaminants involved and their source and transport pathway are unknown. Tainting by phenols has been of specific concern in the past. The work programme comprised: examination of tainting reports; collection of salmonids; their submission for taste testing; literature review; analysis of fish flesh using gas chromatography-mass spectrometry (GCMS) and analysis of river bed sediments. From enquiries, three common descriptors of the 'taint' were identified: disinfectanty; diesely; and muddy. The incidence of taints appears transient/irregular and may therefore relate to the incidence of discharges and specific threshold concentrations of pollutants. The literature review showed that a wide range of organic compounds including many industrial chemicals, and others which are naturally occurring, can taint fish flesh. Taste testing confirmed the presence of tainted salmon and trout in the Ribbie Catchment. It identified a low incidence of 'untainted' fish but demonstrated the 'taint' to be not specific to one tainting substance. Differences were found both between the species and fish from different parts of the catchment. Overall, most fish exhibited an unpleasant flavour, though this may have been influenced to some extent by the fact that most were sexually mature. The worst tainting was found in trout from the river Calder: a soapy/chemical aftertaste. An unpleasant earthy/musty flavour distinguished the salmon from the trout. Phenol was shown to have been a minor issue during the present study, whilst no hydrocarbon taints were identified. Examination of tissue from the eight salmon exhibiting the worst taints revealed the presence of aromatic hydrocarbons, but no phenolic compounds. Other notable substances present in the fish were siioxanes and benzophenone. Data from sediment analysis is presented which shows the main compounds present to be aromatic and polyaromatic hydrocarbons, that concentrations at two locations R. Darwen and R. Calder were significantly higher than at other sites, and that some phenolic compounds were detected at low levels. A paucity of fish flesh taste descriptors linked to specific compounds prevented an obvious correlation to be made between the tastes observed and the organic compounds detected. Descriptors frequently used by the taste testing panel (e.g. earthy, musty, astringency, chemical) cannot be linked to any of the compounds identified in the tissue analyses. No taste information was available from the literature on siioxanes. Aromatic hydrocarbons though present in tissue and sediments were not identified as tainting.

Determinação de atividade antioxidante, compostos fenólicos totais e teor de resveratrol em cinco cultivares brasileiras de Arachis hypogaea L. com a utilização de duas metodologias extrativas

O amendoim A. hypogaea L. é a quarta oleaginosa mais consumida no mundo e suas sementes são altamente energéticas, com grandes quantidades de lipídios, proteínas, vitaminas e carboidratos. Diversas atividades farmacológicas já foram observadas em extratos de raízes, folhas e sementes, sendo a principal delas a atividade antioxidante. Neste trabalho, foi realizada a comparação entre duas metodologias (por maceração e assistida por micro-ondas) para a extração de compostos antioxidantes, incluindo o resveratrol. Também foi realizada a comparação entre extratos de diferentes órgãos de cultivares brasileiras (IAC 886, IAC Caiapó, IAC Tatu ST, IAC 8112 e IAC 99-1) quanto à atividade antioxidante, por DPPH, ao teor de compostos fenólicos, por Folin-Ciocalteu, e ao teor de resveratrol, por HPLC. Por fim, foram estabelecidos protocolos de cultura de tecidos para explantes de sementes, visando à produção de calos e plantas in vitro para posterior dosagem de compostos de interesse, tendo em vista a possibilidade de modulação das condições in vitro. As melhores condições determinadas para a extração por maceração de antioxidantes de A. hypogaea foram 80% de etanol em água como solvente, trituração com almofariz e pistilo, 50 mL solvente por grama de material vegetal seco, 120 minutos de incubação e dois estágios de extração. As melhores condições para a extração de resveratrol assistida por micro-ondas foram o uso de 37 mL de solvente/g material vegetal seco, com agitação de 1200 rpm por 15 minutos, a 37C. De uma maneira geral, os extratos de raízes e oriundos de micro-ondas apresentaram maior atividade antioxidante (até 92,36 2,71%), teor de compostos fenólicos (até 54,15 1,39 mg EAG/g extrato) e teor de resveratrol (até 1,614 0,356 mg/g extrato). Dentre as cultivares estudadas, IAC Tatu e IAC 99-1 foram as que apresentaram os teores mais elevados. Brotos e calos friáveis foram obtidos a partir de cotilédones, eixos embrionários e folíolos embrionários cultivados em meios suplementados com BAP e picloram, respectivamente.

Efeito antimutagênico, antigenotóxico, antiobesidade e antioxidante da Ilex paraguariensis (erva-mate)

O extrato aquoso de erva-mate, obtido a partir de folhas secas de Ilex paraguariensis, é uma bebida amplamente consumida na América do Sul. Inicialmente, nosso objetivo foi caracterizar os compostos presentes nas amostras de erva-mate disponíveis no mercado brasileiro (CH: chimarrão; T: chá mate torrado; G: chá mate torrado, comercialmente acondicionado em garrafas ou C: em copos; TS: chá mate torrado solúvel A mutagenicidade, citotoxicidade e antimutagenicidade de todas as amostras também foram avaliadas atavés do Teste de Ames na presença e na ausência de ativação metabólica. Em seguida, analisamos a amostra TS (2,5, 5,0 e 10 mg/mL) quanto a sua atividade antioxidante e antigenotóxica. Além disso, avaliamos também os efeitos da amostra TS sobre a sinalização da leptina e da insulina no hipotálamo e o estresse oxidativo hepático de ratos adultos obesos programados pela superalimentação neonatal (S). Para induzir S, o tamanho da ninhada foi reduzido a três filhotes por lactante e as ninhadas com número padrão de filhotes (dez/lactante) foram utilizadas como controle. Aos 150 dias de vida, as proles S foram subdivididas em: TS - tratados com extrato aquoso de erva-mate (1g/kg de peso corporal/dia, por gavagem) e S - recebendo água por gavagem durante 30 dias. A prole controle (C) também recebeu água nas mesmas condições do grupo S. Em nossos resultados, verificamos a presença de ácido clorogênico, cafeína e teobromina em todas as amostras analisadas. O conteúdo de compostos fenólicos nas infusões estudadas foram CH: 5,140,23; T: 4,330,01; G: 0,930,25; C: 0,800,3 e TS: 8,350,5 mg/ml. Não observamos efeito mutagênico ou citotóxico nas amostras analisadas. Um efeito antimutagênico significativo foi observado para a cepa TA97 (pré-, co- e pós-tratamento), na presença de ativação metabólica, em todas as amostras testadas. A amostra TS também apresentou um efeito antimutagênico significativo para a TA102 (pré-, co-e e pós-tratamento), na presença de ativação metabólica. Na análise exclusiva da amostra TS, observamos uma atividade antioxidante quando utilizado o ensaio de DPPH, apresentando IC50 69,3+3,1 μg/ml. Além disso, a amostra TS apresentou um efeito protetor sobre a quebra do DNA plasmidial induzida por radicais superóxido e hidroxila, de maneira dose dependente. No teste do cometa, detectamos um efeito antigenotóxico induzido pelo TS em cultura primária de células epiteliais de esôfago. Em nossos testes in vivo observamos que os animais TS não desenvolveram sobrepeso, obesidade visceral e hiperfagia. A resistência hipotalâmica à leptina não foi significativamente revertida, porém a resistência à insulina foi minimizada pelo tratamento com TS no grupo programado pela S. No fígado, TS normalizou as atividades das enzimas antioxidantes (SOD, GPx e CAT) e diminuiu os marcadores de estresse oxidativo, MDA e 4-HNE. O tratamento com TS também reduziu o conteúdo de glicogênio e triglicerídios hepáticos. Nossos resultados sugerem que a erva-mate foi capaz de proteger o DNA contra danos oxidativos, aumentou as defesas antioxidantes, melhorou a função hepática em ratos superalimentados na lactação, talvez através da modulação da sinalização hipotalâmica da insulina podendo ser, portanto, uma importante ferramenta para prevenção e tratamento de doenças relacionadas ao estresse oxidativo.

Desenvolvimento e produção de metabólitos de arruda (Ruta graveolens L.) exposta a substratos contaminados por hidrocarbonetos de petróleo

A indução da síntese de moléculas biologicamente ativas é conhecida como uma estratégia de defesa do organismo vegetal às condições adversas, onde plantas medicinais e/ou aromáticas são foco de pesquisa na terapêutica médica, na indústria farmacêutica, de cosméticos e de alimentos. A possibilidade de que os hidrocarbonetos de petróleo presentes no solo possam agir como agentes elicitores do metabolismo vegetal tem despertado interesse científico. O presente trabalho teve como objetivo avaliar o desenvolvimento in vivo e in vitro de Ruta graveolens L. (Rutaceae), considerando as respostas morfológicas e metabólicas na presença de petróleo e derivados. Além disso, verificar o potencial de desenvolvimento dessa espécie em áreas contaminadas, com base na hipótese de que tais substâncias podem influenciar na produção de substâncias de interesse, sem que haja redução significativa da biomassa vegetal. Foram realizados experimentos de (i) germinação in vivo em solo contaminado e parcialmente biorremediado, assim como solo com contaminação recente com óleo cru (0,8 % e 2,8 %) e diesel comercial S50 (0 % a 6,0 %), sendo que neste último foi avaliado o desenvolvimento e a produção de biomassa das plântulas; (ii) germinação in vitro em meio MS contaminado com fenantreno (1,0; 5,0 e 10,0 mg/L de meio) ou benzo[a]pireno (0,001; 0,010 e 0,100 mg/L de meio), sendo avaliado o desenvolvimento e a produção de biomassa; e (iii) resposta fisiológica de plantas oriundas do estoque in vitro à exposição de fenantreno ou benzo[a]pireno. R. graveolens teve redução significativa da germinação em solos contaminados, principalmente os solos parcialmente biorremediados pelo do processo de bioestímulo; não teve redução significativa da germinação in vivo nos solos contaminados com óleo cru, biorremediado e contaminado com diesel, porém o desenvolvimento pósgerminação foi afetado. Na exposição in vitro aos hidrocarbonetos, não houve alteração significativa na germinação nem na capacidade de desenvolvimento e produção de biomassa nas concentrações testadas de até 10 mg/L de fenantreno e até 0,1 mg/L de benzo[a]pireno. Em relação à propagação in vitro, foi possível a multiplicação de plantas em meio de cultura sem suplementação hormonal, na presença dos contaminantes. A presença de fenantreno e benzo[a]pireno in vitro não promoveu mudanças significativas nos níveis de compostos fenólicos e flavonoides totais produzidos, não havendo também alteração no perfil fitoquímico da espécie, quanto à presença de rutina. Pelo exposto, conclui-se que a espécie tem potencial para uso em biomonitoramento de solos contaminados , considerando a sua capacidade de produzir metabólitos e tolerar a presença dos hidrocarbonetos selecionados, sendo indicada ao cultivo em áreas contaminadas nos níveis investigados

Estabelecimento de culturas de raízes in vitro e avaliação da produção de metabólitos secundários de Cleome spinosa Jacq. (Cleomaceae)

Cleome spinosa é uma espécie herbácea de uso na medicina popular, especialmente no Nordeste do Brasil. A cultura in vitro de raízes adventícias da espécie foi iniciada com segmentos radiculares (0,5 e 1,0 cm) obtidos a partir de duas fontes de explantes: plantas propagadas in vitro e plantas oriundas do processo de germinação in vitro. Os explantes foram inoculados em meio MS líquido suplementado ou não com as auxinas ANA, AIA e AIB em diferentes concentrações (0,5; 1,0; 1,5; 3,0; 5,0 mg.L-1). As culturas foram mantidas em sala de crescimento, sob agitação (100 rpm) e sob fotoperíodo de 16h ou no escuro, com subculturas a cada 45 dias. Explantes oriundos de plantas propagadas in vitro também foram cultivados em meio contendo a citocinina BAP em associação com auxinas, na presença de sorbitol (isoladamente ou em associação com sacarose), em meio MS contendo redução na concentração total de sais minerais (MS1/2 e MS1/4) e em meio sólido. Os resultados mostraram que a adição de auxinas ao meio de cultura foi essencial à multiplicação das raízes, uma vez que em meio MS0 ocorreu significativo desenvolvimento de brotos. A suplementação com ANA não foi eficiente para a produção de raízes e acarretou no calejamento dos explantes, enquanto que a presença de AIA e AIB resultaram na multiplicação das raízes. Ainda assim, independentemente das manipulações realizadas no meio de cultivo, a capacidade de multiplicação mostrou-se reduzida. Uma expressiva multiplicação de raízes foi observada em culturas iniciadas a partir de explantes oriundos de plantas obtidas por germinação in vitro. A maior produção de biomassa foi alcançada em culturas iniciadas com segmentos radiculares de plantas obtidas por germinação in vitro cultivadas em meio contendo com 3,0 mg.L-1 de AIB e mantidas no escuro. Culturas estabelecidas nas melhores condições para acúmulo de biomassa foram acompanhadas por três subculturas, sendo avaliados períodos de cultura de 45 dias e de 60 dias. Culturas mantidas a intervalos de 45 dias apresentaram maior produção de raízes durante a segunda subcultura, enquanto que para o intervalo de 60 dias, embora tenha sido observada a capacidade de multiplicação das raízes, a maior produção de biomassa ocorreu nos primeiros 60 dias de cultivo. A partir de materiais in vivo e in vitro foram realizadas extrações com solventes de polaridade crescente (hexano, diclorometano, acetato de etila e metanol) e os extratos foram submetidos a avaliações cromatográficas. As análises por cromatografia em camada delgada mostraram a presença de terpenos nos extratos obtidos com hexano e diclorometano, tanto em material obtido a campo como naqueles produzidos in vitro e de compostos fenólicos nos extratos em acetato de etila obtidos a partir de material de campo. Pelas análises por cromatografia líquida associada à espectrometria de massas foi possível observar a presença de flavonoides nas culturas in vitro, não detectados no material de campo. As análises por cromatografia de fase gasosa associada à espectrometria de massas apontaram a presença de esteroides nos extratos em hexano de raízes coletadas a campo e nas culturas in vitro de raízes. Os resultados obtidos mostraram a viabilidade da produção de culturas de raízes in vitro para a espécie C. spinosa e o potencial deste material para a produção de substâncias bioativas, algumas não encontradas em material coletado a campo

Evaluation of soot particles of biomass fuels with endocrine-modulating activity in yeast-based bioassay

Exposure to indoor air pollution (IAP) from the combustion of biomass fuels is an important cause of morbidity and mortality in developing countries. In the work discussed in this paper we evaluated the endocrine activity of soot particles from biomass fuels by using yeast bioassay. These pollutants could have beta-galactosidase activity with a relative potency (RP) about 10(-7)-10(-9) that of estradiol. Soot particles from wood and straw combustion only partially induced beta-galactosidase activity whereas others produced fully inductive activity in the yeast assay system. These pollutants did not have estrogen antagonist and progesterone agonist activity within the defined concentration range. However, these pollutants require 2-4 orders of magnitude higher IC50 to inhibit the activity of progesterone in a similar dose-response manner to mifepristone. We therefore propose that the endocrine activity of some environmental pollutants may be because of inhibition of the progesterone receptor (hPR). GC-MS results showed that substituted polycyclic aromatic hydrocarbon (PAH) compounds, substituted phenolic compounds and derivatives, aromatic carbonyl compounds, and phytosteroids in these soot particles may be mimicking endogenous hormones.

Presence of estrogenic activity from emission of fossil fuel combustion as detected by a recombinant yeast bioassay

Estrogenic activities of emission samples generated by fossil fuel combustion were investigated with human estrogen receptor (ER) recombinant yeast bioassay. The results showed that there were weak but clear estrogenic activities in combustion emissions of fossil fuels including coal, petroleum, and diesel. The estrogenic relative potency (RP) of fossil fuel combustion was the highest in petroleum-fired car, followed by coal-fired stove, diesel-fired agrimotor, coal-fired electric power station. On the other hand, the estrogenic relative inductive efficiency (RIE) was the highest in coal-fired stove and coal-fired electric power station, followed by petroleum-fired car and diesel-fired agrimotor. The estrogenic activities in the sub-fractions from chromatographic separation of emitted materials were also determined. The results indicated that different chemical fractions in these complex systems have different estrogenic potencies. The GC/MS analysis of the emission showed that there were many aromatic carbonyls, big molecular alcohol, PAHs and derivatives, and substituted phenolic compounds and derivatives which have been reported as environmental estrogens. The existence of estrogenic substances in fossil fuel combustion demands further investigation of their potential adverse effects on human and on the ecosystem. The magnitude of pollution due to global usage of fossil fuels makes it imperative to understand the issue of fossil fuel-derived endocrine activities and the associated health risks, particularly the aggregated risks stemmed from exposure to toxicants of multiple sources. (C) 2003 Elsevier Science Ltd. All rights reserved.

Defensive and Sensory Chemical Ecology of Brown Algae

The ecological interaction of brown algae are important as these macroalgae are common and often keystone members in many benthic marine communities.This review highlights their chemical interactions,particularly with potential herbivores,but also with fouling oranganisms,with potential pathogens,with each other as gametes,and with their microenvironments when they are spores.Phlorotannins,which are phenolic compounds unique to brown algae,have been studied hesvily in many of these respects and sre highlightes here.This includes recent controversy about their roles as defences against herbivory,as well as new understanding of their roles in primary cellular functions that may,in many instances,be more important than ,and which at least have to be considered in convert with,any possible ecological functions.Brown algae have also been useful models for testing theoties about the evolution of and ecological constraints on chemical defence.Furthermore,their mocroscopic motile gametes and spores have the ability to react to their chemical environments behavirourally.

Electrochemical characteristics of mediated laccase-catalysis and electrochemical detection of environmental pollutants

Laccase has been immobilized on the carbon nanotubes modified glassy carbon electrode surface by adsorption. As-prepared laccase retains good electrocatalytic activity to oxygen reduction by using 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) as the mediator. It can be used as a biosensor for the determination of catechol with broad linear range.

Immobilization and direct electrochemistry of copper-containing enzymes on active carbon

Two typical and important copper-containing enzymes, laccase (Lac) and tyrosinase (Tyr), have been immobilized on the surface of active carbon with simple adsorption method. The cyclic voltammetric results indicated that the active carbon could promote the direct electron transfer of both Lac and Tyr and a pair of well-defined and nearly symmetric redox peaks appeared on the cyclic voltammograms of Lac or Tyr with the formal potential, E-0', independent on the scan rate. The further experimental results showed that the immobilized copper-containing oxidase displayed an excellent electrocatalytic activity to the electrochemical reduction of O-2. The immobilization method presented here has several advantages, such as simplicity, easy to operation and keeping good activity of enzyme etc., and could be further used to study the direct electrochemistry of other redox proteins and enzymes and fabricate the catalysts for biofuel cell.

Organic phase enzyme electrodes based on organohydrogel

A dimethylformamide-polyhydroxyl cellulose organo-hydrogel has been prepared, and its applications for enzyme immobilization in construction of organic phase biosensors have been exploited. With horseradish peroxidase, tyrosinase, and bilirubin oxidase immobilized in the organohydrogel, enzyme electrodes can be operated in various situations, including aqueous buffer, oil/water mixtures, and anhydrous organic solvents, and even in dimethylformamide, to determine analytes of different solubilities, e.g., organic peroxides, phenolic compounds and bilirubin. Biosensing has no restrictions in terms of measuring media and solubilities of analytes.

中国大中型气田天然气成藏物理化学模拟研究

Natural gas pays more important role in the society as clean fuel. Natural gas exploration has been enhanced in recent years in many countries. It also has prospective future in our country through "85" and "95" national research. Many big size gas fields have been discovered in different formations in different basins such as lower and upper Paleozoic in Erdos basin, Tertiary system in Kuche depression in Tarim basin, Triassic system in east of Sichuan basin. Because gas bearing basins had been experienced multiple tectogenesis. The characteristics of natural gases usually in one gas field are that they have multiple source rocks and are multiple maturities and formed in different ages. There has most difficult to research on the gas-rock correlation and mechanism of gas formation. Develop advanced techniques and methods and apply them to solve above problems is necessary. The research is focused on the critical techniques of geochemistry and physical simulation of gas-rock correlation and gas formation. The lists in the following are conclusions through research and lots of experiments. I 8 advanced techniques have been developed or improved about gas-rock correlation and gas migration, accumulation and formation. A series of geochemistry techniques has been developed about analyzing inclusion enclave. They are analyzing gas and liquid composition and biomarker and on-line individual carbon isotope composition in inclusion enclave. These techniques combing the inclusion homogeneous temperature can be applied to study on gas-rock correlation directly and gas migration, filling and formation ages. Technique of on-line determination individual gas carbon isotope composition in kerogen and bitumen thermal pyrolysis is developed. It is applied to determine the source of natural is kerogen thermal degradation or oil pyrolysis. Method of on-line determination individual gas carbon isotope composition in rock thermal simulation has being improved. Based on the "95"former research, on-line determination individual gas carbon isotope composition in different type of maceral and rocks thermal pyrolys is has been determined. The conclusion is that carbon isotope composition of benzene and toluene in homogenous texture kerogen thermal degradation is almost same at different maturity. By comparison, that in mixture type kerogen thermal pyrolysis jumps from step to step with the changes of maturity. This conclusion is a good proof of gas-rock dynamic correlation. 3. Biomarker of rock can be determined directly through research. It solves the problems such as long period preparing sample, light composition losing and sample contamination etc. It can be applied to research the character of source rock and mechanism of source rock expulsion and the path of hydrocarbon migration etc. 4. The process of hydrocarbon dynamic generation in source rock can be seen at every stage applying locating observation and thermal simulation of ESEM. The mechanism of hydrocarbon generation and expulsion in source rock is discussed according to the experiments. This technique is advanced in the world. 5. A sample injection system whose character is higher vacuum, lower leaks and lower blank has been built up to analyze inert gas. He,Ar,Kr and Xe can be determined continuously on one instrument and one injection. This is advanced in domestic. 7. Quality and quantity analysis of benzene ring compounds and phenolic compounds and determination of organic acid and aqueous gas analysis are applied to research the relationship between compounds in formation water and gas formation. This is another new idea to study the gas-rock correlation and gas formation. 8. Inclusion analysis data can be used to calculate the Paleo-fluid density, Paleo-geothermal gradient and Paleo-geopressure gradient and then to calculate the Paleo-fluid potential. It's also a new method to research the direction of hydrocarbon migration and accumulation. 9. Equipment of natural gas formation simulation is produced during the research to probe how the physical properties of rock affect the gas migration and accumulation and what efficiency of gas migrate and factors of gas formation and the models of different type of migration are. II study is focused on that if the source rocks of lower Paleozoic generated hydrocarbon and what the source rocks of weathered formation gas pool and the mechanism of gas formation are though many advanced techniques application. There are four conclusions. 1.The maturity of Majiagou formation source rocks is higher in south than that in north. There also have parts of the higher maturity in middle and east. Anomalous thermal pays important role in big size field formation in middle of basin. 2. The amount of gas generation in high-over maturity source rocks in lower Paleozoic is lager than that of most absorption of source rocks. Lower Paleozoic source rocks are effective source rocks. Universal bitumen exists in Ordovician source rocks to prove that Ordovician source rocks had generated hydrocarbon. Bitumen has some attribution to the middle gas pool formation. 3. Comprehensive gas-rock correlation says that natural gases of north, west, south of middle gas field of basin mainly come from lower Paleozoic source rocks. The attribution ratio of lower Paleozoic source rocks is 60%-70%. Natural gases of other areas mainly come from upper Paleozoic. The attribution ratio of upper Paleozoic source rocks is 70%. 4. Paleozoic gases migration phase of Erdos basin are also interesting. The relative abundance of gasoline aromatic is quite low especially toluene that of which is divided by that of methyl-cyclohexane is less than 0.2 in upper Paleozoic gas pool. The migration phase of upper Paleozoic gas may be aqueous phase. By comparison, the relative abundance of gasoline aromatic is higher in lower Paleozoic gas. The distribution character of gasoline gas is similar with that in source rock thermal simulation. The migration phase of it may be free phase. IH Comprehensive gas-rock correlation is also processed in Kuche depression Tarim basin. The mechanism of gas formation is probed and the gas formation model has been built up. Four conclusions list below. 1. Gases in Kuche depression come from Triassic-Jurassic coal-measure source rocks. They are high-over maturity. Comparatively, the highest maturity area is Kelasu, next is Dabei area, Yinan area. 2. Kerogen thermal degradation is main reason of the dry gas in Kuche depression. Small part of dry gas comes from oil pyrolysis. VI 3.The K12 natural gas lays out some of hydro-gas character. Oil dissolved in the gas. Hydro-gas is also a factor making the gas drier and carbon isotope composition heavier. 4. The mechanism and genesis of KL2 gas pool list as below. Overpressure has being existed in Triassic-Jurassic source rocks since Keche period. Natural gases were expulsed by episode style from overpressure source rocks. Hetero-face was main migration style of gas, oil and water at that time. The fluids transferred the pressure of source rocks when they migrated and then separated when they got in reservoir. After that, natural gas migrated up and accumulated and formed with the techno-genesis. Tectonic extrusion made the natural gas overpressure continuously. When the pressure was up to the critical pressure, the C6-C7 composition in natural gas changed. The results were that relative abundance of alkane and aromatic decreased while cycloalkane and isoparaffin increased. There was lots of natural gas filling during every tectonic. The main factors of overpressure of natural gas were tectonic extrusion and fluid transferring pressure of source rocks. Well preservation was also important in the KL2 gas pool formation. The reserves of gas can satisfy the need of pipeline where is from west to east. IV A good idea of natural gas migration and accumulation modeling whose apparent character is real core and formation condition is suggested to model the physical process of gas formation. Following is the modeling results. 1. Modeling results prove that the gas accumulation rule under cap layer and gas fraction on migration path. 2. Natural gas migration as free phase is difficult in dense rock. 3. Natural gases accumulated easily in good physical properties reservoirs where are under the plugging layer. Under the condition of that permeability of rock is more than 1 * 10~(-3)μm~(-1), the more better the physical properties and the more bigger pore of rock, the more easier the gas accumulation in there. On the contrary, natural gas canonly migrate further to accumulate in good physical properties of rock. 4. Natural gas migrate up is different from that down. Under the same situation, the amount of gas migration up is lager than that of gas migration down and the distance of migration up is 3 times as that of migration down. 5. After gas leaks from dense confining layer, the ability of its dynamic plug-back decreased apparently. Gas lost from these arils easily. These confining layer can confine again only after geology condition changes. 6. Water-wetted and capillary-blocking rocks can't block water but gases generally. The result is that water can migrate continuously through blocking rocks but the gases stay under the blocking rocks then form in there. The experiments have proved the formation model of deep basin gas.