Glutamate dehydrogenase a (GDHa) has been suggested as a potential drug target against the malaria parasite Plasmodium falciparum. GDHa knockout cell line was generated and needed a phenotypic description by means of molecular biology and biochemistry. The knockout cell line was tested for higher oxidative stress sensitivity, levels of relevant proteins and gene transcripts were quantified. Furthermore, concentrations of two key molecules enabling redox homeostasis, glutathione and NADPH, were attempted to quantify. Finally, we attempted to disrupt a gene of another glutamate dehydrogenase, gdhb, which did not result in formation of viable parasites. In conclusion, GDHa is not a suitable drug target and GDHb needs to be further elucidated.

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / Objetivou-se avaliar os efeitos da adiÃÃo do anacardato de cÃlcio como fonte de Ãcido anacÃrdico na raÃÃo de codornas japonesas em postura quanto ao desempenho e parÃmetros de qualidade dos ovos. Foram utilizadas 252 codornas japonesas em fase de postura com 22 semanas de idade, distribuÃdas em delineamento inteiramente casualizado com seis tratamentos e seis repetiÃÃes de sete aves. Os tratamentos aplicados foram: T1 - raÃÃo sem promotor de crescimento (PC); T2 - raÃÃo com promotor de crescimento; T3, T4, T5 e T6 - raÃÃes sem promotor de crescimento e adiÃÃo de 0,25; 0,50; 0,75 e 1,0% de anacardato de cÃlcio (AC), respectivamente. Os tratamentos nÃo influenciaram o consumo de raÃÃo, percentagem de postura, peso do ovo, massa de ovo, conversÃo alimentar e a qualidade dos ovos: percentagem de gema, albÃmen e casca, unidade Haugh, densidade especÃfica, espessura da casca e cor da gema. O anacardato de cÃlcio como fonte de Ãcido anacÃrdico, quando adicionado atà 1% na raÃÃo nÃo influencia o desempenho e qualidade dos ovos de codornas japonesas. / The aim of the study was to evaluate the effects of adding calcium anacardate as source of anacardic acid in Japanese laying quails diets on performance and egg quality parameters. A total of 252 Japanese laying quails with 22 weeks of age were used, distributed in completely randomized design, with six treatments and six replications of seven broilers each. The treatments used were: T1 - diet without growth promoter (PC); T2 - diet with growth promoter; T3, T4, T5 and T6 - diets without growth promoter and addition of 0,25; 0,50; 0,75 and 1,0% of calcium anacardate (AC), respectively. The treatments did not affect feed intake, laying percentage, egg weight, egg mass, feed conversion and quality of the eggs: yolk, albumen and shell percentage, Haugh unit, specific gravity, shell thickness and yolk color. The calcium anacardate as source of anacardic acid, when added up to 1% in the diet, does not affect the performance and quality of the eggs of Japanese laying quails.

Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia e Ciência de Alimentos, Escola de Química e Alimentos, 2009. / Submitted by Caroline Silva (krol_bilhar@hotmail.com) on 2012-08-27T19:37:20Z No. of bitstreams: 1 dissertao cintia_defesa.pdf: 808863 bytes, checksum: d9ab57cfdbf88e2f2fc31318462a352c (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2012-12-01T16:33:40Z (GMT) No. of bitstreams: 1 dissertao cintia_defesa.pdf: 808863 bytes, checksum: d9ab57cfdbf88e2f2fc31318462a352c (MD5) / Made available in DSpace on 2012-12-01T16:33:40Z (GMT). No. of bitstreams: 1 dissertao cintia_defesa.pdf: 808863 bytes, checksum: d9ab57cfdbf88e2f2fc31318462a352c (MD5) Previous issue date: 2009 / As propriedades nutricionais da microalga Spirulina têm sido relacionadas com possíveis propriedades antioxidantes, caracterizando-a no âmbito dos alimentos funcionais. Os antioxidantes são compostos que atuam inibindo e/ou diminuindo efeitos desencadeados pelo estresse oxidativo, conservando a harmonia entre a produção fisiológica de radicais livres e sua detoxificação. Objetivou-se avaliar o potencial antioxidante da microalga Spirulina e seu principal pigmento, a ficocianina, em situações de estresse oxidativo induzido. Foram realizados estudos com células da levedura Saccharomyces cerevisiae, submetidas a estresse oxidativo pela adição de 1,1´-dimetil-4,4´-bipiridilo (paraquat) nas concentrações 0, 10 e 15 mM, avaliando o potencial antioxidante da Spirulina através da sobrevivência celular (plaqueamento) e da lipoperoxidação (índice de substâncias reativas ao ácido tiobarbitúrico, TBA). Também foi avaliado o efeito protetor da Spirulina e/ou da ficocianina em córtex cerebral de ratos submetidos a estresse oxidativo por administração de glutamato monossódico ou por situação de pânico. No córtex dos animais foram avaliados os índices de TBA e a atividade específica das enzimas superóxido dismutase (SOD) e catalase (CAT). O uso do herbicida paraquat nas concentrações 10 mM e 15mM, diminuiu a sobrevivência celular da levedura em relação ao controle (39,4 % e 17,1%, respectivamente) e aumentou significativamente a lipoperoxidação (p≤0,05). O agente estressor glutamato monossódico provocou aumento significativo (p≤0,05) da lipoperoxidação e diminuição significativa (p≤0,05) das atividades específicas das enzimas SOD e CAT no córtex cerebral dos ratos. O estresse por situação de pânico também provocou alterações significativas (p≤0,05) no córtex dos ratos, aumentando a peroxidação lipídica e a atividade da enzima SOD e diminuindo a atividade da enzima CAT. O uso da Spirulina, bem como da ficocianina, atenuaram os efeitos deletérios decorrentes do estresse oxidativo induzido em células de leveduras e em córtex de ratos, mantendo os parâmetros dos grupos tratados com estressor e antioxidante estatisticamente iguais aos do grupo controle. Estes resultados contribuem com a caracterização da microalga no âmbito dos alimentos funcionais antioxidantes. / The nutritional properties of the microalgae Spirulina have been related with possible therapeutical properties, characterizing it in the scope of functional and nutraceutical foods mainly had its antioxidant potential. The antioxidant substances are composites that act inhibiting and/or decreasing the effect unchained of oxidative stress, conserving the balance between physiological production of free radicals and its detoxification. It was objectified to evaluatethe antioxidant potential of the microalgae Spirulina and its main pigment, the phycocyanin, in situation of oxidative stress induced. studies whit cells of Saccharomyces cerevisiae yeast had been carried, submitted oxidative stress for the addition of 1,1´-dimetil-4,4´-bipiridilo (paraquat) in concentrations 0, 10 and 15 mM, evaluating the antioxidant potential of the Spirulina throught the cellular survival and reactives substances index to the tiobarbituric acid (TBA). Also was evaluated the protective effect of the Spirulina and phycocyanin, in cerebral cortex of rats submitted to oxidative stress induced for glutamate monosodic administration or panic situation. In the cortex of animals the TBA index, and activity of enzymes superoxide dismutase (SOD) and catalase (CAT) had been evaluated. The use of paraquat in concentrations 10 mM and 15mM, decreased yeast cellular survival in relation to the control (39.4% and 17.1%, respectively) and increased the lipoperoxidation significantly (p≤0,05). The estressor agent glutamate monossodic provoked significant increase (p≤0,05) in lipoperoxidation and significant reduction (p≤0,05) of enzymes SOD and CAT in the cerebral cortex of the rats. The oxidative stress for panic situation also provoked significant alterations (p≤0,05) in the cortex of the rats, increasing the lipidic peroxidation and the activity of enzyme SOD and diminishing the activity of enzyme CAT. The use of the Spirulina, as well as phycocyanin, had attenuated the decurrent deleterious effect of oxidative stress induced in cells of yeast and in cortex of rats, keeping the parameters of the groups dealt with statistical equal stressor and antioxidant substance to the ones of the group has controlled. These results contribute with the characterization of the microalgae in the scope of antioxidant functional foods.

Master of Science / Department of Animal Sciences and Industry / James S. Drouillard / Since the 1960’s liver abscess incidence and severity have been identified as a problem associated with feeding high concentrate finishing rations to feedlot cattle. Liver abscesses lead to decreased feedlot performance and decreased carcass value. Tylosin phosphate is a macrolide antibiotic commonly used by feedlots throughout the United States and has been shown to successfully control liver abscesses. In 2013, the FDA issued Guidance for Industry #213, which encourages reduced usage of medically important classes of antibiotics, such as macrolides, in animal feed. This will be achieved by implementing veterinary oversight of these drugs via Veterinary Feed Directives (VFD). Thus, it is of importance to find alternative strategies to reduce usage of tylosin in finishing rations to control liver abscesses. One strategy that has been suggested is increasing dietary roughage concentration. However, this isn’t a viable option as increasing dietary roughage concentration not only leads to a decline in feedlot performance, hot carcass weight, and dressing percentage, but also has an environmental impact. Available research has also indicated that increasing dietary roughage has no impact on liver abscess incidence or severity. Our research objective was therefore to identify alternative strategies to reduce liver abscess incidence. Our first trial evaluated the impact of antioxidants on liver abscess incidence and severity. Treatments consisted of a control treatment (basal diet containing 200 IU/d α-tocopherol acetate), and an antioxidant treatment (basal diet containing 2000 IU/d α-tocopherol acetate and 500 mg/d crystalline ascorbate). Treatments were randomly assigned to 390 crossbred heifers. No differences in feedlot performance were detected; however, there was a tendency for improved feed intake (P = 0.075) and feed efficiency (P = 0.066) for heifers that received the antioxidant treatment. An increased number of yield grade 3 carcasses (P = 0.03) and fewer yield grade 1 carcasses (P < 0.01) was observed in the antioxidant treatment group. No differences were detected between treatments for other carcass characteristics or liver abscess incidence and severity. Another trial evaluated intermittent tylosin feeding and its impact on liver abscess incidence and antimicrobial resistant Enterococcus spp. when compared to continuous tylosin feeding. One of 3 treatments were randomly assigned to 312 crossbred steers: negative control (no tylosin fed throughout the feeding period); positive control (tylosin fed throughout the feeding period); or intermittent treatment (tylosin fed intermittently throughout the feeding period: 1week on, 2 weeks off). Fecal samples were collected on day 0, 20, and 118 to characterize antimicrobial resistant Enterococcus spp. By design, the intermittent treatment consumed 60% less tylosin than the positive control group. No differences were detected between treatments for feedlot performance. Liver abscess incidence was greatest for the negative control, and least for the positive control and intermittent treatments, with no difference being detected between the latter two treatments (P = 0.716). Antimicrobial resistance was unaffected by treatment, but was affected by sampling time. We concluded that supplementing antioxidants is not a viable option to reduce liver abscess incidence and severity, and that tylosin usage can be decreased without adversely affecting performance or liver abscess incidence.

>Magister Scientiae - MSc / South Africa is one of two countries responsible for the production of approximately 80% of the world’s Zr. The increase in mining activity has detrimental effects on the environment, especially crop plants, as more pollutants are leached into the soil. Consequently, it is necessary to understand how plants respond to this form of abiotic stress. Therefore, this study focused on determining the physiological and biochemical responses of two genotypes of Brassica napus L (Agamax and Garnet) in response to Zr stress. The levels of cell death, lipid peroxidation and ROS were higher in Garnet, whereas the chlorophyll content was higher in Agamax. Furthermore, native PAGE analysis detected seven SOD isoforms and seven APX isoforms in Agamax, compared to 6 SOD isoforms and 7 APX isoforms in Garnet. The results thus indicate that Agamax is tolerant to Zr-induced stress, whereas Garnet is sensitive. An assay for the rapid quantification of Zr within plant samples was subsequently developed, which revealed that Agamax retained the bulk of the Zr within its roots, whereas Garnet translocated most of the Zr to its leaves. The ability of Agamax to sequester Zr in its roots comes forth as one of the mechanisms which confers greater tolerance to Zr-induced stress. As a consequence, our study sought to use the optical, physical and chemical properties of quantum dots to image the uptake and translocation of Zr in B. napus genotypes. ICPOES was also performed to quantify Zr levels in various plant organs. Data from the ICPOES revealed varying patterns of uptake and translocations between Garnet and Agamax. These patterns were similarly shown in IVIS Lumina images, tracing the transport of QD/Zr conjugates. This method ultimately proved to be successful in tracing the uptake of Zr, and could essentially be a useful tool for targeting and imaging a number of other molecules.

This study was conducted to investigate the physico-chemical properties and antioxidant activity of five pomegranates fruit (Punica granatum L.) cultivars grown in Iran. Significant differences were found among the pomegranate cultivars for many of the properties studied. Results showed that, in particular, fruit diameter ranged from 63.63 mm (Syah) to 79.29 mm (Rabab), fruit volume from 153.3 cm3 (Syah) to 293.3 cm3 (Rabab), fruit density from 0.93 g cm-3 (Rabab) to 1.13 g cm-3 (Torsh Sefeed). Although Syah showed the lowest fruit weight (144.8 g), fruit yield (8.28 ton ha–1) and fruit skin thickness (1.55 mm), Rabab had the highest fruit yield (27.1 ton ha–1) and fruit skin thickness (2.32 mm). Juice volume was between 61.1 and 67.0 cm3. Percent of aril ranged from 59.64% (Rabab) to 75.3% (Syah) and weight of aril was between 108.9 and 199.8 g. Also, results indicated that titratable acidity content varied from 0.39% (Syah) to 1.13% (Torsh Sefeed). The total soluble solids content varied from 12.67 ◦Brix (Torsh Sefeed) to 15.67 ◦Brix (Zardeh Anar), pH values from 3.05 to 3.77, Electrical conductivity values from 2.8 to 3.14 dSm-1 and vitamin C content from 59.25 to 69.52 mg 100g1. The anthocyanins content was observed between 80.36 (Syah) and 216.97 (Zardeh Anar). The antioxidant activity of pomegranate cultivars ranged from 27.24% (Syah) to 84.04% (Torsh Sefeed). These results demonstrated that the cultivar was the major factor which influences the morpho-pomological and chemical (especially, antioxidant activity), properties in pomegranates.

Selenenic acids and other organoselenium compounds are important both in organic and biochemistry. In organic chemistry, syn-elemination of selenoxides is used to prepare alkenes, giving a selenenic acid by-product. In biochemistry, selenocysteine is catalytically active in a variety of selenoenzymes, which have antioxidant properties, and is oxidized to a selenenic acid intermediate. For example, glutathione peroxidase (GPx) plays a role in fighting oxidative damage by catalyzing the reduction of hydroperoxides. Previous studies have shown that the lighter chalcogen analogue of selenenic acid, sulfenic acid, is a powerful antioxidant and that the known antioxidant activity of garlic is attributable to the 2-propenesulfenic acid derived from the compound allicin. This has prompted questions concerning the role of selenenic acid in the antioxidant activity of organoselenium compounds. In order to study the physiochemical properties of selenenic acids –a functional group about which little is known—and to evaluate their potential as antioxidants, a persistent selenenic acid is needed. Herein, the model compound, 9-triptyceneselenenic acid, is prepared by a previously reported procedure and a new pathway is designed, such that its properties and reactivity can be studied. The oxidation of thiols is important in cell signalling, leading to the disulfide bonds implicated in post-translational modification, among other biological roles. While this reaction is presumed to occur through the reaction of thiol with an oxidant that forms sulfenic acid, and from a subsequent reaction of sulfenic acid with another thiol, sulfenic acids are so reactive that they are not usually seen as intermediates. Given the stability of the 9-triptycenesulfenic acid previously synthesized, preliminary kinetic study of the oxidation of 9-triptycenethiol to its corresponding sulfenic acid is made possible.

Edible pulse seeds are good sources of food ingredients. Germination has been regarded as an effective process to further improve nutrient digestibility and accessibility of pulse seeds. Our aim was to observe the effect of germination on proximate composition, physicochemical attributes, and phenolic profiles of chickpea (Cicer arietinum L.), lentil (Lens culinaris Merr.), and yellow pea (Pisum sativum L.). In addition, mechanisms of how germination affects the antioxidant activity of phenolic compounds were proposed. Chemical composition, thermal, pasting, and moisture adsorption properties of pulse flours were investigated over 6 days of germination. Protein contents increased by 3 percent points for all pulses over germination. However, lentil had the highest protein content. Lipid contents decreased over germination with chickpea having the greatest decline, from 8.00 to 5.90 g/100g (d.b.). Total starch decreased in lentil and yellow pea during germination. Thermal properties of pulse flours changed slightly, while pasting properties varied among pulses. The highest final viscosities for chickpea, lentil, and yellow pea flours were 1061, 981, and 1052 cP and were observed after 2, 1, and 0 days of germination, respectively. Moisture adsorption isotherms showed improved water adsorption capabilities after germination. Soluble free (SFPs) and polar soluble bound phenolic compounds (PSBPs) were extracted from germinated pulse seeds. Their antioxidant activities were evaluated using both the in vitro system and stripped soybean oil (SSO)-in-water emulsions. Liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry and size-exclusion chromatography with multiangle-light-scattering and refractive-index detection were employed to analyze the phenolic composition and molar mass, respectively. Antioxidant activities of SFPs increased in both in vitro and SSO-in-water emulsion system, however, much lower than those of PSBPs based on SSO-in-water emulsion system. The effect of germination on PSBPs in SSO-in-water emulsion varied between pulses. By virtue of chemometric analysis, nine phenolic compounds were speculated as the pivotal phenolic compounds responsible for the antioxidant activity of PSBPs. In particular, the molar masses of PSBPs had a positive relationship with their antioxidant activity. Protective and co-antioxidative principles were proposed as reasons for the variability of antioxidant activities of PSBPs in oil-in-water emulsions with germination. / Hatch project number ND01593

This thesis is focused on the study of the effectiveness of active ingredients from natural extracts such as milk thistle and turmeric. The thesis describes the use of modern methods of analysis and identification of active substances located in plants of milk thistle and turmeric. In the experimental part of thesis, which was preceded by a literature search focused on the biological effects of active substances in the chosen natural extracts, the extracts were characterized according to group characteristics (total assessment of polyphenols and flavonoids, assessment of antioxidant activity, and assessment of vitamin C volume and tocopherol). The next part is focused on the study of the encapsulation of natural active substances into the organic particles: liposomes. Silymarin and curcumin were encapsulated as active substances. The idea of a plant with a single active ingredient is usually erroneous. Plants usually contain hundreds of components which cooperate on a given effect. Therefore, the majority of herbalists believe that a simple plant is an active ingredient. However, some plants are known to be containing a particular active phytochemical. For instance, plants such as the milk thistle, turmeric, or a ginkgo are great examples of the plant containing a particular active phytochemical. In these cases, the active compound is disproportionately more effective than the plant itself. Encapsulation efficiency of active ingredients of Silymarin and curcumin was determined by HPLC/PDA. The aim of the analysis was to observe the behavior of elements during the incubation in surrounding of gastric juice model, and the stability while maintaining the particles in model food.

Written records about medicinal plants date back at least 5,000 years to the Sumerians. The objected plants for present investigation were indigenous to South Africa and as explored, only a few biological studies were found on the previous studies on Hyaenanche globosa and Maytenus procumbens. Phytochemical studies of the ethanol extract of the fruits of H. g/obosa (F.E) resulted in isolation of two known pure sesquiterpene lactones; 'tutin 1' and 'hyenanchin 2'. The crude extract and its isolated constituents were tested on four cancerous and a normal cell lines. F.E exhibited the highest antiproliferative activity on Hela cells which followed by Caco-2 cells. None of the isolated compounds were found to be toxic to the cells tested in this experiment. F.E demonstrated potent inhibition of DPPH radical activity similar to vitamin C. 'Tutin 1' and 'hyenanchin 2' were found with marginal antioxidant activity of which 'compound 1' presented more potent activity than 'compound 2'. The amounts of ROS radicals formed by pure compounds (1 and 2) were not significantly higher than those of controls. This is the first report on phytochemical index, anticancer, antioxidant and antibacterial properties of F.E and its purified compounds. The possible biochemical activities of the acetonic/ethanolic extract of the leaves of Maytenus procumbens (L.M.P), and its isolated compounds were investigated in the present study. L.M.P showed IC50 values of 68.79, 51.22, 78.49, 76.59 and 76.64 ì/ml on Caco-2, Hela, HT29, NIH3T3 and T47D cells by use of MTT cytotoxicity assay. Bioassay guided fractionation led to the isolation and identification of two new triterpenes: '30-hydroxy-11á-hydroxy-18â-olean-12-en-3-one 3' and '30-hydroxy-11á-methoxy- 18â-olean-12-en-3-one 5'. In addition, a known terpenoid: 'asiatic acid 4' was purified. Due to the unavailability of sufficient amount of 'asiatic acid 4', this compound was not tested. Pure compounds 3 and 5 exhibited the most cytotoxicity against Hela cells and were further investigated for their abilities for induction of apoptosis (at the concentration of their IC sub>50) in Hela cells using flow cytometric method. Both compounds induced apoptosis up to 73.20%, (compound 3) and 20.40% (compound 5) in Hela cells versus control group (0.40%). Antioxidant/oxidative properties of L.M.P and its isolated compounds were investigated using extracellular (DPPH), and intracellular reactive oxygen species (ROS) assays. L.M.P and the isolated compounds exhibited marginal DPPH discoloration. Experimental samples represented a time and concentrationdependent function of ROS formation in Hela cells. ROS generation might be a part of the mechanisms by which compounds 3 and 5 induced apoptosis in Hela cells. It can therefore be concluded that the active components in L.M.P might serve as a mediator of the reactive oxygen scavenging system and have the potential to act as a prooxidant and an antioxidant, depending on the biological environment of the cells. There is no report until date on phytochemical index, anticancer, antioxidant and antibacterial properties of L.M.P and its isolated compounds. / Thesis (PhD)--University of Pretoria, 2012. / Plant Science / unrestricted