This thesis examines the role of dissolved inorganic nutrients in generating changes in phytoplankton community and pigment composition and if such changes can affect the production of the antioxidant astaxanthin in the ecosystem via pelagic copepods. The background of my studies is the possible relationship between eutrophication and a reproductive disturbance in Baltic populations of Atlantic salmon (M74), which is associated with astaxanthin and thiamine deficiencies and oxidative stress. In the southern Baltic Sea, changes in nutrient loads correlate with observed trends of flagellates replacing diatoms in the phytoplankton. Copepods are the main producers of astaxanthin and a major link between phytoplankton and higher trophic levels. In laboratory and field experiments in the Baltic Sea proper and the Norwegian Sea, I show that astaxanthin synthesis in copepods is fast and depends on pigment composition of the phytoplankton diet. Among single-species diets, a diatom and a green algal cyst yielded the highest astaxanthin levels in copepods, and another diatom species, a green alga and a cyanobacterium the lowest. In nutrient-generated phytoplankton blooms in mesocosms, copepods grazing on diverse communities dominated by weakly silicified diatoms produced more astaxanthin compared with copepods grazing on communities dominated by strongly silicified diatoms. This suggests that diatoms invested in defence mechanisms and escaped grazing at surplus Si. A nutrient-starved diatom culture subjected to intraspecific competition exhibited decreased pigment levels, increased thiamine levels and increased oxidative stress. My results suggest that diatoms are beneficial for astaxanthin and thiamine production compared to other phytoplankton groups, but not under all circumstances. Copepod growth and development also responded to inorganic nutrient availability and affected total astaxanthin production per volume seawater, with highest production when the copepods grazed on diatoms. From an ecosystem perspective, increased N and P loads seem to promote high astaxanthin production, but not when diatoms disappear completely.

Darbo objektas - paprastoji pušis (Pinus sylvestris L.) – Lietuvoje labiausiai paplitusi, jautri užterštam orui medžių rūšis. Paprastosios pušies tyrimai buvo atliekami Lietuvos įmonių AB “Achema” apylinkėse 25 km ruože nuo gamyklos, AB „Akmenės cementas“ 10 km ruože ir AB „Mažeikių nafta“ – 5.4 km ruože nuo gamyklos. Darbo tikslas – Įvertinti paprastosios pušies (Pinus sylvestris L.) spyglių pigmentinės ir antioksidantinės sistemų priklausomybę nuo medynų atstumo iki taršos šaltinio. Darbo metodas. Tyrimai atlikti 14-oje pušyn����������, nutolusių skirtingu atstumu nuo gamyklų: JonA apylinkėse 5 medynai 25 km ruože, šalia AkmC – 4 medynai 10,0 km ruože, šalia MažN – 5 medynai 5,4 km ruože. Šakos, specialiais kirtikliais pjautos 6-8 metrų virš žemės aukštyje. Spygliai buvo atšaldomi ledu ir transportuojami i laboratoriją. Atskirai tiriami pirmamečiai ir antramečiai spygliai. Pigmentų ir askorbo rūgšties koncentracijų nustatymui naudota žalioji spyglių masė. Pigmentams tirti ėminiai buvo ekstrahuojami nedideliu 100 % acetono kiekiu. Spektrofotometru (Genesys 5) išmatuota pigmentų ekstrakto absorbcija 662 nm (chlorofilas a), 644 nm (chlorofilas b), 440,5 nm (karotinoidai) bangos ilgyje. Askorbo rūgštis spygliuose buvo ekstrahuojama su 0.001 N 2,6 dichlorfenolindofenoliu ir titruojama. Darbo rezultatai. Tyrimai AB “Akmenės cementas” transektoje parodė, kad, fotosintezės pigmentų kiekiai reikšmingai mažesni prie gamyklos 0,5 km atstumu augančiose pušyse nei tolimiausiame (10 km... [toliau žr. visą tekstą] / Object of the research – Scots pine (Pinus sylvestris L.) – common tree in Lithuania, sensitive to air pollution. Research of Scots pine were conducted in the industrial areas of Lithuania companies JSC – (25 km transect) near the factory JSC (10 km sector) and an oil refinery (in 2 – 5,4 km distance). Goal of the research – to evaluate quality of photosynthetic pigments and ascorbic acid in the needles of Scots pine growing around main sources of industrial pollution. Methodology of the research. Research was performed in 17 pine forests, at different distance from the factories. In the surroundings of the nitrogen fertilizer factory 8 forests were examined in 25 km distance, near the cement factory – 4 forests in 10 km distance and near the oil refinery – 5 forests in 5.4 km distance. In each site, samples of current-year and 1-year-old needles were taken from 4 pines at the height of 6-8 m aboveground. The needles were cooled and transported to laboratory. Concentrations of the pigments and ascorbic acid were determined in the fresh needle material. The needles were grinded and in 20ml of 100% acetone. The absorbance at 662 nm (chlorophyll a), 644 nm (chlorophyll b) and 440.5 nm (carotenoids) was measured by spectrophotometer (Genesys 5, US). The ascorbic acid from the needles was extracted with 0.001 N 2.6-dichlorophenolindophenol and estimated titrimetrically. Results of the research. Research results showed that number of photosynthesis pigments is meaningly... [to full text]

Disertacijoje nagrinėjamas galimas aplinkos poveikis organinių molekulių elektroninių būsenų savybėms. Tam tikslui yra naudojami kompiuterizuotieji kvantinės mechanikos metodai, kuriais remiantis nagrinėjamos įvairių molekulių savybės. Ištirtos 2-(N-metil-α-iminoethyl)-fenol ir N-triphenylmethylsalicylidene imine molekelulių, esančių poliniame tirpiklyje, struktūros pagrindinėje ir sužadintose elektroninėse būsenose. Pirmą kartą parodyta, kad, norint gauti teisingą kokybinį ir artimą kiekybiniam vidujmolekulinės protono pernašos potencinės energijos paviršių, būtina atsižvelgti į polinių tirpiklio molekulių kuriamą vandenilinių ryšių tinklą bei į nulinių svyravimų energijas. Pastarieji ir nulemia protono pernašos vyksmo kryptį bei efektyvumą. Parodyta, kad anilų klasės molekulių konformerų susiformavimas priklauso nuo tirpiklio poliškumo, o jų susidarymas savo ruožtu konkuruoja su klasterių iš tirpiklio molekulių susiformavimo galimybėmis. Pirmą kartą parodyta, kad dipolinio momento vertė bakteriorodopsine yra nulemta membranos paviršiuose esančių radikalų. Pademonstruota, kad stilbazolio molekulė deformuojasi ir sudaro naujus konformerus (pademonstruota dviejų formų atsiradimo galimybė) tik esant molekulėms tirpalo apsuptyje. Šis rezultatas paaiškino eksperimente stebimus skirtuminių spektrinių pokyčių evoliucijos prigimtį. Apskaičiuotos ir išanalizuotos karotinoidų - luteino, violaksantino ir zeaksantino molekulių - žemiausios sužadintos elektroninės būsenos. Parodyta... [toliau žr. visą tekstą] / To explore changes caused by the environment on the internal characteristics of an organic molecule is the objective of the thesis. For this purpose we investigate a variety of organic molecules. Using various methods of quantum mechanics calculations possible influence of a polar solvent on the ground and excited states of 2-(N-metil-α-iminoethyl)-fenol and N-triphenylmethylsalicylidene imine is considered. It is shown for the first time that in order to obtain the correct qualitative and quantitative interpretation of possible pathways of the intermolecular proton transfer the hydrogen network of the polar solvent molecules together with the zero point energy have to be taken into consideration. It is also shown that conformational variability of anil-type molecules in polar solvents is competing with clusters formation of solvent molecules. It is shown for the first time that the dipole moment of bacteriorhodopsin is mainly defined by cytoplasmic and extracellular coils on the surfaces of the membrane. It is also demonstrated that the stilbazole molecule experiences the deformation resulting in formation of new conformers (at least two forms are present) in the solvent surrounding. The experimental data of the transient spectroscopy were explained in the basis of these model calculations. The lowest excited states of carotinoids, such as lutein, zeaxanthin and violoxantin are calculated and analyzed. Sensitivity of the excited electronic state on the polar environment is... [to full text]

Objectif : Examiner l’association entre la consommation alimentaire de caroténoïdes (β-carotène, α-carotène, β-cryptoxanthine, lutéine/zéaxanthine, lycopène) et de vitamine C et le risque de cancer du poumon, selon le sexe, l’intensité de tabagisme et le sous-type histologique de la tumeur. Méthodes : Les données proviennent d’une étude cas-témoins menée à Montréal, Canada. Des entrevues ont été effectuées auprès de 1 105 cas incidents de cancer du poumon et 1 449 témoins issus de la population générale. Leur fréquence de consommation moyenne de 49 fruits et légumes deux ans auparavant a été convertie en apports en antioxydants. Les rapports de cotes (RC) et les intervalles de confiance (IC) à 95% caractérisant l’association entre les antioxydants et le risque de cancer du poumon ont été estimés à l’aide de modèles de régression logistique et polytomée, en tenant compte de facteurs de confusion potentiels. Résultats : Une consommation élevée en antioxydants était généralement associée à une diminution du risque de cancer du poumon de l’ordre de 30%. Un effet protecteur a été observé chez les hommes et les femmes, pour les non fumeurs, les fumeurs quelque soit l’intensité de tabagisme, ainsi que pour les carcinomes à petites cellules, épidermoïde et l’adénocarcinome. Conclusions : Plusieurs antioxydants alimentaires protégeraient du cancer du poumon. Les efforts de prévention bénéficieraient de cibler la promotion de la consommation de fruits et de légumes riches en caroténoïdes et en vitamine C. / Objective: To investigate the association between dietary intake of carotenoids (β-carotene, α-carotene, β-cryptoxanthin, lutein/zeaxanthin and lycopene) and vitamin C, and risk of lung cancer according to sex, smoking intensity and tumor histological subtype. Methods: In the course of a case-control study conducted in Montreal, Canada, in-person interviews elicited dietary data from 1,105 incident lung cancer cases and 1,449 population controls. Usual frequency of intake of 49 fruit and vegetables two years prior to diagnosis or interview was estimated and converted to antioxidant intakes. Odds ratios (OR) and 95% confidence intervals (CI) between intake variables and lung cancer were estimated using logistic and polytomous regression models, adjusting for potential confounding factors. Results: High intakes of antioxidants were generally associated with some 30% reduction in lung cancer risk. A protective effect was observed among men and women, among never smokers, smokers regardless of intensity, and for small cell carcinoma, squamous cell carcinoma and adenocarcinoma. Conclusions: Results from this study suggest several dietary antioxidants may protect against lung cancer. Prevention programs should promote increased intakes of fruit and vegetables rich in carotenoids and vitamin C.

Disertacijoje nagrinėjamas galimas aplinkos poveikis organinių molekulių elektroninių būsenų savybėms. Tam tikslui yra naudojami kompiuterizuotieji kvantinės mechanikos metodai, kuriais remiantis nagrinėjamos įvairių molekulių savybės. Ištirtos 2-(N-metil-α-iminoethyl)-fenol ir N-triphenylmethylsalicylidene imine molekelulių, esančių poliniame tirpiklyje, struktūros pagrindinėje ir sužadintose elektroninėse būsenose. Pirmą kartą parodyta, kad, norint gauti teisingą kokybinį ir artimą kiekybiniam vidujmolekulinės protono pernašos potencinės energijos paviršių, būtina atsižvelgti į polinių tirpiklio molekulių kuriamą vandenilinių ryšių tinklą bei į nulinių svyravimų energijas. Pastarieji ir nulemia protono pernašos vyksmo kryptį bei efektyvumą. Parodyta, kad anilų klasės molekulių konformerų susiformavimas priklauso nuo tirpiklio poliškumo, o jų susidarymas savo ruožtu konkuruoja su klasterių iš tirpiklio molekulių susiformavimo galimybėmis. Pirmą kartą parodyta, kad dipolinio momento vertė bakteriorodopsine yra nulemta membranos paviršiuose esančių radikalų. Pademonstruota, kad stilbazolio molekulė deformuojasi ir sudaro naujus konformerus (pademonstruota dviejų formų atsiradimo galimybė) tik esant molekulėms tirpalo apsuptyje. Šis rezultatas paaiškino eksperimente stebimus skirtuminių spektrinių pokyčių evoliucijos prigimtį. Apskaičiuotos ir išanalizuotos karotinoidų - luteino, violaksantino ir zeaksantino molekulių - žemiausios sužadintos elektroninės būsenos. Parodyta... [toliau žr. visą tekstą] / To explore changes caused by the environment on the internal characteristics of an organic molecule is the objective of the thesis. For this purpose we investigate a variety of organic molecules. Using various methods of quantum mechanics calculations possible influence of a polar solvent on the ground and excited states of 2-(N-metil-α-iminoethyl)-fenol and N-triphenylmethylsalicylidene imine is considered. It is shown for the first time that in order to obtain the correct qualitative and quantitative interpretation of possible pathways of the intermolecular proton transfer the hydrogen network of the polar solvent molecules together with the zero point energy have to be taken into consideration. It is also shown that conformational variability of anil-type molecules in polar solvents is competing with clusters formation of solvent molecules. It is shown for the first time that the dipole moment of bacteriorhodopsin is mainly defined by cytoplasmic and extracellular coils on the surfaces of the membrane. It is also demonstrated that the stilbazole molecule experiences the deformation resulting in formation of new conformers (at least two forms are present) in the solvent surrounding. The experimental data of the transient spectroscopy were explained in the basis of these model calculations. The lowest excited states of carotinoids, such as lutein, zeaxanthin and violoxantin are calculated and analyzed. Sensitivity of the excited electronic state on the polar environment is... [to full text]

Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-03-17T15:14:09Z No. of bitstreams: 1 JéssicaBMM_DISSERT.pdf: 581155 bytes, checksum: 7e403d68146a4eae342ccc4a752f27c5 (MD5) / Made available in DSpace on 2017-03-17T15:14:09Z (GMT). No. of bitstreams: 1 JéssicaBMM_DISSERT.pdf: 581155 bytes, checksum: 7e403d68146a4eae342ccc4a752f27c5 (MD5) Previous issue date: 2016-05-25 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Moringa oleifera leaves are considered a promising food for the Northeast because of its nutritional profile and its ability to be keeping green during periods of drought. The research objective was to evaluate the physical and chemical composition and digestibility and energy value of sheets of dried moringa for birds. The chemical analyzes were carried out for crude protein, dry matter, ether extract, neutral detergent fiber and acid detergent fiber, ash and gross energy by the conventional method and the next spectrometry method of infrared. In the measurement of chlorophyll and the main bioactive compounds such as anthocyanins, total carotenoids, flavonoids yellow, total extractable polyphenols and vitamin C through the spectrometric method. The results of the composition of the dried leaves of the Moringa showed that it has good crude protein (30.93%) for conventional analysis and analysis in NIRS (31.64%) anthocyanins (1.02 mg / 100g), carotenoids total (1.48 mg / kg), chlorophyll (120.62 mg / kg), yellow flavonoids (25.76 mg / 100g), polyphenols (105.15 mg / 100g), especially the amount of vitamin C (485.71 mg / 100g). In the digestibility trial, 20 adult birds were housed individually in cages adapted for excreta collection, with five treatments (0, 5, 10, 15 and 20% inclusion of moringa leaves), distributed in a completely randomized design. For apparent digestibility of diets with increasing levels of inclusion of dehydrated leaves of Moringa oleifera was observed a decreasing linear effect for mineral matter (MM)), y = 27.3120 - 0,4934x, (R2 = 0.65) , ether extract (EE), y = 87.3124 - 0,9394x, (R2 = 0.72); neutral detergent fiber (NDF), y = 29.6686 - 0,2957x, (R2 = 0.61); acid detergent fiber (ADF), y = 20.2322 - 0,1688x, (R2 = 0.68); for the metabolization coefficient of gross energy (GE), y = 72.4564 - 0,4285x, (R2 = 0.77) and apparent metabolizable energy of feed (EMA) y = 3783.96 - 15,52x ( R2 = 0.29). With exeção of dry matter (DM) and crude protein (CP), that no significant effects. The value of apparent metabolizable energy of moringa leaves for adult birds was 2.155,81kcal / kg, a value obtained by Matterson technique. Also the coefficient of energy metabolism (CME) with 47.44% for moringa leaf was observed / As folhas de Moringa oleífera são consideradas um alimento promissor para região nordeste, devido ao seu perfil nutricional e sua capacidade de ser manter verde durante os períodos de estiagem. Diante disso, objetivou-se avaliar a composição físicoquímica e a digestibilidade e o valor energético das folhas de moringa desidratadas para aves. As análises bromatológicas foram realizadas quanto aos teores de proteína bruta, matéria seca, extrato etéreo, fibra em detergente neutro e fibra em detergente ácido, cinzas e energia bruta pelo método convencional e pelo método de espectrometria próxima de infravermelho. Além da quantificação de clorofila a e principais compostos bioativos como: antocianinas, caratenoides totais, flavonoides amarelos, polifenóis extraíveis totais e vitamina C, através do método de espectrometria. Os resultados da composição das folhas desidratadas da moringa mostraram que a mesma apresenta bons teores de proteína bruta (30,93%) para análises convencionais e para análises no NIRS (31,64%) antocianinas (1,02 mg/100g), carotenoides totais (1,48 mg/kg), clorofila a (120,62 mg/kg), flavonoides amarelos (25,76 mg/100g), polifenóis (105,15 mg/100g) , destacando-se a quantidade de vitamina C (485,71 mg/100g). No ensaio de digestibilidade, 20 aves adultas foram alojadas individualmente em gaiolas metálicas adaptadas para coleta total de excretas, com cinco tratamentos (0, 5, 10, 15 e 20% de inclusão das folhas de moringa), distribuídas em delineamento inteiramente casualizado. Para coeficientes de digestibilidade aparente das rações com níveis crescentes de inclusão de folhas desidratadas de Moringa oleífera, foi observado um efeito linear decrescente para matéria mineral (MM) ), y= 27,3120 – 0,4934x, (R2 = 0,65), extrato etéreo (EE), y= 87,3124 – 0,9394x, (R2 = 0,72); fibra em detergente neutro (FDN), y= 29,6686 - 0,2957x, (R2 = 0,61); fibra em detergente ácido (FDA), y= 20,2322 – 0,1688x, (R2 = 0,68); para o coeficiente de metabolização de energia bruta (EB), y= 72,4564 – 0,4285x, (R2 = 0,77) e para energia metabolizável aparente das rações (EMA) y= 3783,96 – 15,52x, (R2 = 0,29). Com exeção da matéria seca (MS) e da proteína bruta (PB),que não observados efeitos significativos. O valor de energia metabolizável aparente das folhas de moringa para aves adultas foi de 2.155,81kcal/kg, valor este obtido através da técnica de Matterson. Também foi observado o coeficiente de metabolização de energia (CME) com 47,44 % para folha de moringa / 2017-03-16

Purpose of this research was to investigate physiological differences between monocots (Digitaria horizontalis) and dicots (Emilia coccinea) in function on the application of the mixture of herbicides clomazone + ametryn and its relation with mortality of these species. For this, conducted two experiments, one for each species, where was applied the herbicide mixture in four doses: 0 (water); 2.5 L. ha-1 (0.5 kg a.i ha-1 of clomazone + 0.75 kg a.i.ha-1 of ametrina) ; 5 L. ha-1 ( 1 kg a.i ha-1 of clomazone + 1.5 kg a.i ha-1 of ametrina) e 10 L. ha- 1 (2 kg a.i ha-1 of clomazone + 3 kg a.i ha-1 of ametrina), when the plants were 30 days after sowing. Physiological variables studied were levels of photosynthetic pigments, chlorophyll fluorescence emission, superoxide dismutase (SOD) activity, ascorbate peroxidase (APX) activity, electrolyte leakage and lipid peroxidation 72 hours after the apliccation. After 25 days of the application were counted the frequency of dead plants and dry matter accumulation per plant. The data were submitted to analysis of variance and exponential or linear regression analysis. The total chlorophyll and carotenoids decreased exponentially with increasing doses of the mixture in the two species studied. The values of maximum fluorescence (Fm), maximum quantum yield (Fv/Fm) and effective quantum yield (YIELD) also decreased exponentially for both species, since the minimal fluorescence (Fo) decreased linearly for both. The SOD activity decreased linearly in both species, but this decrease was more pronounced in monocots. The APX showed no significant change in its activity. The dicots showed a linear increase more pronounced in electrolyte leakage compared with the monocot. For lipid peroxidation, the species were similar to those electrolyte leakage. In relation to plant mortality, the dose of 10 L.ha-1 eliminated only 53.84% of the population of D. horizontalis while the same dose for E. coccinea eliminated 100% of the population. Given the observations, concluded that the species that suffered the greatest damage of the cell membrane was obtained more reduction in dry matter per plant and a higher percentage of mortality. And other mechanisms than those evaluated in this study may be related to increased tolerance of D. horizontalis to mixture of ametryn+clomazone. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O objetivo da pesquisa foi verificar diferenças fisiológicas entre mono (Digitaria horizontalis) e dicotiledôneas (Emilia coccinea) em função da aplicação da mistura de herbicidas clomazone+ametrina e sua relação com a mortalidade dessas espécies. Para isso, foram realizados dois experimentos, um para cada espécie, onde aplicou-se a mistura de herbicidas clomazone e ametrina, em quatro doses: 0 (água); 2,5 L. ha-1 (0,5 kg i.a ha-1 de clomazone + 0,75 kg i.a.ha-1 de ametrina) ; 5 L. ha-1 ( 1 kg i.a ha-1 de clomazone + 1,5 kg i.a ha-1 de ametrina) e 10 L. ha-1 (2 kg i.a ha-1 de clomazone + 3 kg i.a ha-1 de ametrina), aos 30 dias após a semeadura. As variáveis fisiológicas estudadas foram: teores de pigmentos fotossintéticos, emissão da fluorescência da clorofila a, proteínas solúveis, atividade da superóxido dismutase (SOD), atividade da ascorbato peroxidase (APX), extravasamento de eletrólitos e peroxidação de lipídeos 72 horas após a aplicação. Após 25 dias da aplicação foi contabilizada a frequência de plantas mortas e a matéria seca acumulada por planta. Os dados foram submetidos à análise de variância e análise de regressão exponencial ou linear. Os teores clorofila totais e carotenóides decresceram exponencialmente com o aumento das doses da mistura de herbicidas, nas duas espécies estudas. Os valores do rendimento quântico potencial (Fv/Fm), rendimento quântico efetivo (YIELD) e fluorescência máxima (Fm) também decresceram exponencialmente para as duas espécies, já a fluorescência inicial (Fo) decresceu linearmente para ambas. A atividade da SOD decresceu linearmente em ambas as espécies, porém esse decréscimo foi mais acentuado na monocotiledônea. Não houve alteração significativa da atividade da APX. A dicotiledônea apresentou aumento linear mais acentuado no extravasamento de eletrólitos comparado com a monocotiledônea. Para a peroxidação de lipídios, as espécies apresentaram comportamento semelhante aos de extravasamento de eletrólitos. Em relação à mortalidade das plantas, a dose de 10 L.ha-1 eliminou apenas 53,84% da população de D. horizontalis enquanto a mesma dose eliminou 100% da população de E. coccinea. Diante das observações, conclui-se que a espécie que sofreu maior dano de membranas celulares foi a que obteve maior redução na meteria seca por planta e maior percentual de mortalidade. Outros mecanismos que não os avaliados nessa pesquisa podem estar relacionados com a maior tolerância de D. horizontalis à mistura de ametrina+clomazone.

CAVALCANTE, Kelma Maria dos Santos Pires. Avaliação do potencial antioxidante de macroalgas marinhas do litoral cearense. 2012. 122 f. : Tese (doutorado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortaleza-CE, 2012 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-27T13:00:44Z No. of bitstreams: 1 2012_tese_kmspcavalcante.pdf: 783385 bytes, checksum: 8eabc3394f4206e331baee2a713c7002 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-27T13:00:57Z (GMT) No. of bitstreams: 1 2012_tese_kmspcavalcante.pdf: 783385 bytes, checksum: 8eabc3394f4206e331baee2a713c7002 (MD5) / Made available in DSpace on 2016-07-27T13:00:57Z (GMT). No. of bitstreams: 1 2012_tese_kmspcavalcante.pdf: 783385 bytes, checksum: 8eabc3394f4206e331baee2a713c7002 (MD5) Previous issue date: 2012 / Seaweeds are sources of a wide variety of beneficial compounds for human. Many of these compounds have antioxidant activity, such as phenolic compounds, carotenoids, and vitamin E. The aim of this research was to evaluate the in vitro antioxidant activity of 50% methanolic extracts from seaweed collected in the coastline of Ceará State, Brazil. The methods used were: DPPH radical scavenging, ferrous ion chelation (FIC), ferric reducing antioxidant power (FRAP), and β-carotene bleaching. In addition to in vitro antioxidant activity, the total phenolic content (TPC) was measured by the Folin-Ciocalteu method, followed by a phytochemical prospecting to point out which are the main classes of compounds present in the algal extracts. The quantification of carotenoids (α- and β-carotene, and lutein) and vitamin E (α- and -tocopherol) was carried out by HPLC. In general, the extracts of brown algae showed the highest ability to scavenger the DPPH radical, the largest FRAP and the highest TPC, followed by extracts of green and red algae. The greatest FIC was observed in red alga extracts, followed by brown and green alga extracts. The high antioxidant activity in β-carotene/linoleic acid model system of green and red alga extracts ranged from 65% to 95%, however it represented less than 40% in brown alga extracts, exception to Padina gymnospora extract which presented activity up to 92%. The majority of the algal extracts analyzed in this study presented activity similar to or even greater than those observed in positive controls (quercetin, BHA, BHT, ascorbic acid, α-tocopherol, β-carotene and EDTA). Fenols were detected in brown algae only; anthocyanins, anthocyanidins, chacons, aurons and leucoanthocyanins were observed in some species of Rhodophyta Phylum. All the other classes of phenolic compounds were found in at least one species within each Phylum, exception to flavononols which have not been detected in green alga extracts. TPC was the main responsible for the ability to scavenger the DPPH radical, FIC and FRAP in green and red algae. On the other hand, in brown algae TCP was influenced only by FRAP. All extracts of green, red and brown algae exhibited the presence of β-carotene and lutein. The latter was the major carotenoid within Chlorophyta and Rhodophyta. Naturally absent in brown algae, α-carotene was not detected in five species of Chlorophyta and Rhodophyta algae. α-Tocopherol was determined in all species, except Ulva fasciata and U. lactuca extracts. The isomer δ-tocopherol was quantified in eleven out of twenty-three alga species. Antioxidant activity and levels of compounds in the algal extracts were different, but all of them showed antioxidant potential. / As macroalgas marinhas são fontes de compostos com atividade antioxidante como compostos fenólicos, pigmentos carotenóides e vitamina E. O objetivo deste trabalho foi avaliar a atividade antioxidante in vitro de extratos metanólicos (50%) de macroalgas cearenses, através da capacidade de sequestrar o DPPH, habilidade de quelação do íon ferroso (FIC), poder de redução do ferro (FRAP) e degradação do β-caroteno. Além disso, também foi determinado o conteúdo de compostos fenólicos pelo método de Folin-Ciocalteu, seguido de uma prospecção fitoquímica para indicar possivelmente as principais classes de compostos. Os teores de α- e β-caroteno, luteína e α- e -tocoferol foram quantificados por cromatografia líquida de alta eficiência. De um modo geral, capacidade de sequestrar o DPPH, FRAP e conteúdo de compostos fenólicos foram maiores nos extratos das algas pardas, seguidos dos das algas verdes e vermelhas. FIC mais elevada foi observada nos extratos das algas vermelhas, seguidas das pardas e verdes. No sistema modelo β-caroteno/ácido linoléico as maiores atividades foram determinadas nas clorófitas e rodófitas, tendo variado de 64,8% a 95,3%, nas ocrófitas, inferiores a 40,5%, com exceção de Padina gymnospora com cerca de 92%. Os extratos algáceos analisados apresentaram atividades antioxidantes semelhantes ou superiores aos controles positivos (quercetina, BHA, BHT, ácido ascórbico, α-tocoferol, β-caroteno e EDTA). Fenóis foram detectados apenas em algas pardas; antocianinas, antocianidinas, chaconas, auronas e leucoantocianidinas foram observadas apenas em algumas espécies do Filo Rhodophyta; as demais classes de compostos fenólicos investigadas foram observadas em pelo menos uma espécie dentro de cada Filo, com exceção de flavanonóis que não foram encontrados nos extratos de algas verdes. O conteúdo de compostos fenólicos foi o principal responsável pelas atividades de sequestro do DPPH, FRAP e FIC nas algas verdes e vermelhas. Nas pardas esses compostos só influenciaram no FRAP. β-Caroteno e luteína foram quantificados em todos os extratos de algas verdes, vermelhas e pardas, sendo a luteína o carotenóide majoritário nas clorófitas e rodófitas. Com exceção das algas pardas que naturalmente não possuem α-caroteno, apenas os extratos de cinco espécies de clorófitas e rodófitas não apresentaram esse composto. Todos os extratos analisados apresentaram α-tocoferol, menos Ulva fasciata e U. lactuca. Extratos de onze espécies apresentaram δ-tocoferol. As atividades antioxidantes e os teores de compostos detectados nos extratos algáceos foram distintos, mas todos eles apresentaram potencial antioxidante.

O presente trabalho avaliou o crescimento da microalga Dunaliella tertiolecta pela biofixação do CO2 liberado pela produção de cerveja, reciclando um dos gases responsáveis pelo efeito estufa, reduzindo custo da matéria-prima CO2 e agregando valor ao produzir lipídeos e carotenoides naturais. Para isso a microalga foi cultivada em sistemas integrados entre fotobiorreatores e fermentadores. A diferença nos cultivos foi o tipo e a quantidade de CO2 produzida pelas fermentações. Inicialmente se fez fermentações com meio YPD (Yeast Peptone Dextrose) em fermentadores de 2 L acoplados a cada 24 h aos fotobiorreatores em 4 condições distintas, sendo o último fermentador colocado sempre em 144 h de cultivo de microalgas: 30 g L-1 de dextrose a partir de 72 h de cultivo de microalgas, 60 g L-1 de dextrose a partir de 72 h de cultivo de microalgas, 30 g L-1 de dextrose a partir de 24 h de cultivo de microalgas e variando a concentração de (10 à 60) g L-1 de dextrose a partir de 24 h de cultivo de microalgas (YPD (10-60)/24). Os maiores valores para biomassa, carotenoides, produtividades e lipídeos foram obtidos na condição YPD (10-60)/24. Para reproduzir a essa condição utilizando mosto de cerveja, foi calculada a conversão de substrato em produto para, então, acoplar diariamente volumes diferentes de mosto de cerveja em cultivos de microalgas. Os valores obtidos para os cultivos com CO2 desprendidos por estas fermentações foram 1,10 ± 0,05 g L-1 de biomassa, 0,18 ± 0,01 g L-1 d-1 de produtividade de biomassa, 0,58 ± 0,06 d-1 foi a velocidade específica de crescimento, 4,74 ± 0,59 mg g-1 de carotenoides por biomassa, 0,86 ± 0,06 mg L-1 d-1 de produtividade de carotenoides e 13,5 ± 0,4 % (em massa) de lipídeos. Estes valores foram praticamente o dobro dos valores obtidos para o cultivo com CO2 do ar atmosférico, demonstrando que a integração entre fermentadores e fotobiorreatores é uma boa alternativa para indústria alimentícia. Todos cultivos com D. tertiolecta apresentaram o mesmo perfil de carotenoides representado por 46,7 ± 2,0 % de luteína, 22,5 ± 1,6 % de β-caroteno, 9,50 ± 0,66 % de zeaxantina, 1,10 ± 0,16 % de α-caroteno e 20,2 ± 3,0 % para outros. / This study evaluated the growth of microalgae Dunaliella tertiolecta for CO2 biofixation released by brewing, recycling one of the greenhouse gases, reducing cost of raw material CO2 and adding value to produce lipids and natural carotenoids. For this, microalgae were cultivated in integrated systems between photobioreactors and fermenters. The difference in the cultures was the culture medium and the amount of CO2 produced. Initially, fermentation with medium YPD (Yeast Peptone Dextrose) in 2 L fermenters were coupled every 24 h to photobioreactors in 4 different conditions: 30 g L-1 of dextrose from 72 h culture of microalgae; 60 g L-1 of dextrose from 72 h culture of microalgae; 30 g L-1 of dextrose from 24 h culture of microalgae; and ranging dextrose concentration of (10 to 60) g L-1 from 24 h culture of microalgae (YPD (10-60)/24). The highest values for biomass, carotenoids, productivities and lipids were obtained in the condition YPD (10-60)/24. To reproduce this condition using beer wort, the substrate to product yield was determined and different volumes of beer wort where daily coupled to microalgae cultivations. The values obtained for cultures with CO2 released from these fermentations were 1.10 ± 0.05 g L-1 of biomass, 0.18 ± 0.01 g L-1 d-1 of biomass productivity, 0.58 ± 0.06 d-1 for the specific growth rate, 4.74 ± 0,59 mg g-1 of carotenoids per biomass, 0.86 ± 0.06 mg L-1 d-1 of carotenoids productivity and 13.5 ± 0.4 % (mass fraction) of lipids. These values were almost twice the values observed in the cultivation with CO2 of atmospheric air, showing that the integration between fermenters and photobioreactors is a good alternative to increase microalgae growth. All cultures with D. tertiolecta showed the same profile of carotenoids represented by 46.7 ± 2.0 % of lutein, 22.5 ± 1.6 % of β-carotene, 9.50 ± 0.66 % of zeaxanthin, 1.10 ± 0.16 % of α-carotene and 20.2 ± 3.0 % for others.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Atherosclerosis is a chronic inflammatory disease that is characterized by the accumulation of lipids and fibrous elements in the intima layer of arteries of medium and large caliber. The cardiovascular diseases resulting from atherosclerosis, among them acute myocardial infarction and stroke are the leading cause of mortality and morbidity worldwide. Oxidative stress and oxidative modification of low density lipoprotein (LDL) have an important role in the development of this disease and so the inclusion of antioxidants in the diet may prevent the progression of atherosclerosis. The carotenoid norbixin (NBX), which is found in annatto seeds, have excellent antioxidant activity as demonstrated in several models of oxidative damage. In this context, the objective of this study was to evaluate the antioxidant, anti-inflammatory and antiatherogenic potential of NBX in a model of atherosclerosis in rabbits. Male New Zealand rabbits received regular chow (control) or an atherogenic diet (0.5% cholesterol) alone or supplemented with NBX (10, 30 or 100 mg/kg) for 60 days. The antioxidant enzyme activities, lipid profiles, oxidative stress and inflammatory markers and histopathological status were evaluated in the serum or aortic tissue. The atherogenic diet increased serum lipids, oxidized low-density lipoprotein (LDLox) levels and oxidized low-density lipoprotein antibody (LDLoxAB) levels, in addition to inducing lipid and protein oxidation in the aortic tissue. Supplementation with NBX caused 35% reduction in the levels of LDLoxAB, 69% in the levels of LDLox, 27% in the levels of TBARS and 46% in the levels of protein carbonyl induced by the atherogenic diet, besides increasing up to 88% the HDL levels. In atherosclerotic rabbits, the non-protein thiol group content and enzymatic activity of the antioxidants superoxide dismutase, catalase, glutathione reductase and thioredoxin reductase were increased in aortic tissue, whereas paraoxonase activity was reduced in serum. Supplementation with NBX restored up to 41% the increased levels of NPSH, 37% SOD activity, 45% CAT activity, 66% GR activity, 50% TrxR-1 activity induced by the atherogenic diet. NBX also restored 15% of PON1 activity inhibited by the atherogenic diet. The atherogenic diet also increased the serum levels of inflammatory markers and the ratio of the intima area to the media area in the aortic arch; these changes were not prevented by NBX. Thus, NBX supplementation improved the lipid profile, decreased oxidative stress and prevented changes in paraoxonase activity and in the antioxidant system in hypercholesterolemic rabbits, but did not prevent the formation of atherosclerotic plaques. These results support a beneficial role of NBX in the treatment of atherosclerosis by preventing oxidative events and by restoring antioxidant enzyme activity and paraoxonase activity. / A aterosclerose é uma doença inflamatória crônica caracterizada pelo acúmulo de lipídeos e elementos fibrosos na túnica intima das artérias de médio e grande calibre. As doenças cardiovasculares decorrentes da aterosclerose, dentre elas o infarto agudo do miocárdio e o acidente vascular cerebral são a principal causa de mortalidade e morbidade mundial. O estresse oxidativo e a modificação oxidativa da lipoproteína de baixa densidade (LDL) possuem um papel importante no desenvolvimento dessa doença. Por este motivo a inclusão de antioxidantes na dieta poderia impedir a progressão da aterosclerose. O carotenóide norbixina (NBX), presente nas sementes de urucum, possui excelente atividade antioxidante já demonstrada em diversos modelos de dano oxidativo. Nesse contexto, o objetivo deste trabalho foi avaliar o potencial antioxidante, anti-inflamatório e antiaterogênico da NBX em um modelo de aterosclerose em coelhos. Coelhos Nova Zelândia machos receberam ração regular (controle) ou uma dieta aterogênica (0,5% de colesterol) sozinha ou suplementada com NBX (10, 30 ou 100 mg/kg) por 60 dias. A atividade das enzimas antioxidantes, o perfil lipídico, os marcadores de estresse oxidativo e inflamação e as alterações histopatológicas foram avaliados no soro ou tecido aórtico dos coelhos hipercolesterolêmicos. A dieta aterogênica aumentou os níveis séricos de lipídios, de lipoproteína de baixa densidade oxidada (LDLox) e de anticorpos contra lipoproteína de baixa densidade oxidada (LDLoxAB), além de induzir a oxidação de lipídios e proteína no tecido aórtico. A suplementação com NBX reduziu em até 35% o aumento dos níveis de LDLoxAB, 69% dos níveis de LDLox, 27% dos níveis de TBARS e 46% dos níveis de proteínas carboniladas induzidos pela dieta aterogênica, além de aumentar em até 88% os níveis de HDL. Nos coelhos ateroscleróticos ocorreu uma elevação no conteúdo de grupos tiólicos não-protéicos (NPSH) e na atividade das enzimas antioxidantes superóxido dismutase (SOD), catalase (CAT), glutationa redutase (GR) e tioredoxina redutase (TrxR-1) no tecido aórtico, enquanto a atividade da enzima paraoxonase (PON1) foi reduzida no soro. A suplementação com NBX reduziu em até 41% o aumento dos níveis de NPSH, 37% da atividade da SOD, 45% da atividade da CAT, 66% da atividade da GR e 50% da atividade da TrxR-1 induzidos pela dieta aterogênica. A NBX também restaurou em 15% a atividade da PON1 inibida pela dieta aterogênica. A dieta aterogênica também aumentou os níveis séricos de marcadores inflamatórios e a relação entre a área da íntima e da média no arco aórtico e essas mudanças não foram prevenidas pela NBX. Assim, a suplementação com NBX melhorou o perfil lipídico, diminuiu o estresse oxidativo e impediu mudanças na atividade da paraoxonase e no sistema antioxidante em coelhos hipercolesterolêmicos, mas não impediu a formação de placas ateroscleróticas. Esses resultados indicam um papel benéfico da NBX no tratamento de aterosclerose, impedindo eventos oxidativo e restaurando a atividade das enzimas antioxidantes e da enzima paraoxonase.