Orientador: Marcelo Carnier Dornelas / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T02:41:48Z (GMT). No. of bitstreams: 1 Cutri_Lucas_D.pdf: 2714790 bytes, checksum: 166e8f9c13b78486aa747c098642efc0 (MD5) Previous issue date: 2013 / Resumo: O gênero Passiflora é representado por lianas e pequenos arbustos que totalizam cerca de 600 espécies. As flores deste gênero possuem uma série de inovações fisiológicas e morfológicas, que possibilitam a adaptação a diferentes tipos de polinizadores. Os compostos voláteis que compõem o aroma destas flores contribuem para o sucesso reprodutivo destas espécies, uma vez que atuam na atração de polinizadores específicos. Os constituintes voláteis emitidos pelas flores são em sua grande maioria lipofílicos com baixo peso molecular e pertencem a diferentes classes de metabólitos vegetais. O objetivo deste trabalho foi analisar os componentes voláteis presentes no aroma de três espécies de Passiflora com diferentes síndromes de polinização: melitofilia, ornitofilia e quiropterofilia (Passiflora edulis, P. coccinea e P. mucronata, respectivamente). As análises foram realizadas utilizando técnicas de micro extração em fase sólida (SPME) associada à cromatografia gasosa e espectrometria de massas (GC-MS). Os resultados sugerem diferenças no padrão de substâncias voláteis detectas no "headspace" floral das espécies P. edulis e P. coccinea e P. mucronata. P. aedulis possui como componentes voláteis majoritários os benzenóides metoxilados provenientes da via dos fenilpropanóides; P. coccinea possui principalmente terpenóides e P. mucronata possui terpenóides, alcanos, derivado de ácido graxo e substância contendo enxofre. No banco de etiquetas de seqüências expressas (ESTs) de tecidos reprodutivos de P. edulis (PASSIOMA) foram encontradas seqüências similares a genes relacionados à via de biosbiossíntese de componentes voláteis. Destes, PePAL e PeOMT, potencialmente envolvidos na produção de benzenóides metoxilados, que também são encontrados em outras espécies vegetais polinizadas por insetos, tiveram seus padrões de expressão analisados em tecidos de flores de P. edulis por RT-PCR quantitativa ou semi-quantitativa e por hibridização in situ. Os resultados sugerem que a via de fenilpropanóides está ativa em tecidos florais de P. edulis potencialmente envolvidos na emissão de voláteis, especialmente no tecido epitelial da corona, o qual apresenta características ultraestruturais de células secretoras. O trabalho corrobora com a observação de diferença no padrão de componentes voláteis em flores de Passiflora, e apresenta dois genes candidatos envolvidos na produção de uma classe de metabolitos especializados em P. edulis / Abstract: The genus Passiflora comprises more than 600 species of lianas and small shrubs. The typical flowers of Passiflora congregate a series of morphological and physiologic innovations that allow adaptation to a number of pollinating agents. The volatile compounds present in the flower scent ("headspace") are important features to the effective reproduction of plant species since they act in the attraction of the correct pollinating agent. These compounds emitted by flowers are basically of low-molecular weight, mostly lipophilic and are represented by very different chemical classes. The aim of this work was the analysis of the volatile compounds present in the floral "headspace" of three different Passiflora species pollinated by bees, hummingbirds and bats (Passiflora edulis, P. coccinea and P. mucronata, respectively). Solid phase micro extraction (SPME) coupled to GC-MS analysis was the analytical tool in that study. The results showed different patterns of volatile compounds in the floral "headspace" of P. edulis, P. coccinea and P. mucronata. The "headspace" of P. edulis contained phenylproanoids mostly represented by methylated benzenes, P. coccinea, terpenes and P. mucronata terpenes, alkanes, fatty acid derivative, and sulphur-containing compounds. Genes potentially involved with the synthesis of key enzymes of volatile compounds pathways were identified in an Expressed Sequence Tag (EST) database obtained from reproductive tissues of P. edulis (PASSIOMA). Among these PePAL and PeOMT possibly involved with the production of methylated benzenes that acting in the insect attraction in different plant species. PePAL and PeOMT had their expression patterns analyzed by quantitative and semi-quantitative RT-PCR as well as by in situ hybridization. This approach confirmed that the phenylpropanoid pathway is active in flowers of P. edulis, especially in the epithelial tissue in corona filaments that has ultra-structural features of secretor cells. This work emphasizes the chemical differences in scent flower among Passiflora species, and shows two genes potentially involved in scent flowers production in P. edulis / Doutorado / Biologia Vegetal / Doutor em Biologia Vegetal

Diabetes mellitus is a growing threat to human health. Current pharmacological agents cause undesirable side-effects. Herbal remedies offer the potential for alternative treatment strategies that may prove more cost-effective and devoid of the undesirable side-effects. The purpose of this study was to evaluate the in vitro anti-diabetic activity of aqueous and methanol extracts of Sclerocarya birrea (A. Rich.) Hochst. (Anacardiaceae) and Ziziphus mucronata Willd. (Rhamnaceae), which are traditionally used for the treatment of diabetes mellitus in southern Africa. Polyphenolic contents of extracts were quantified using the aluminium trichloride and Folin-Ciocalteau methods. The capacity of individual extracts to scavenge both the 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and 2,2-diphenyl-1-picrylhydrazyl radicals was used as a measure of antioxidant activity. The inhibitory activities of the crude extracts of both plants on the enzymes, α-amylase and α-glucosidase, were determined using colorimetric assays. The effects of the crude extracts on cell viability was assessed in C2C12 myotubes, HepG2 hepatocarcinoma cells, 3T3-L1 adipocytes and RIN-m5F pancreatic β-islet cells, using the Sulforhodamine B assay. Fluorescence detection was used to investigate the effects of the crude extracts on glucose uptake in C2C12, HepG2 and 3T3-L1 cells. Insulin secretion was assessed in RIN-m5F cells, using ELISA. Crude extracts of both plants contained flavonoids and phenols, but flavonoid content was predominantly higher. All the extracts displayed antioxidant activity, with the methanol extract of S. birrea possessing the most potent free radical scavenging ability (IC50 = 2.16 μg/ml). Aqueous and methanol extracts of S. birrea displayed significantly (p < 0.05) greater inhibition of α-amylase, than the positive control, acarbose. Only the methanol extract of Z. mucronata inhibited α-amylase activity. Furthermore, crude extracts of both plants also displayed potent α-glucosidase inhibitory activity. Most of the crude extracts had low toxicity, where concentrations of 100 μg/ml of crude extract of the plants did not induce 50% cell death. iv Although no significant increase in insulin secretion from cultured RIN-m5F cells was noted, the crude extracts of both plants significantly (p < 0.05) increased glucose uptake in C2C12, HepG2 and 3T3-L1 cells, with efficacy significantly (p < 0.05) higher than the positive control, insulin. From the results, the plant extracts appear to exert their hypoglycaemic effects independently of insulin, via an extra-pancreatic mechanism, possibly involving interactions with the different receptors. An additive hypoglycaemic effect originates from the inhibition of both α-amylase and α-glucosidase. The findings of the present study provide evidence that S. birrea and Z. mucronata possess in vitro anti-diabetic activity. Further investigations are required to elucidate the mechanism(s) of action of the crude extracts using more targeted in vitro assays. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Pharmacology / unrestricted

Historical. General descriptions of intertidal zonation have been published by many workers for almost all littoral areas, both marine and lacustrine (Doty, 1957; Glynn, 1965; Hedgpeth, 1957; Lewis, 1964; Pennak, 1951). The fact that animal species of the sandy shore are few in number eliminates many complex interspecific reactions, while great numbers of individuals make population studies feasible. In addition to certain general works (Dahl, 1952; Pirrie et al., 1932; Yonge, 1950) a number of papers have discussed causative factors or mechanisms for animal zonation.

Biogenic structures can impart important information regarding animal behaviors and depositional conditions at the time of colonization including: sedimentation rate, current velocities, distribution of food resources, oxygenation, salinity, and temperature. This thesis utilizes various ichnological subdisciplines to build upon these underlying ichnological principles. Neoichnology is a newly emerging field that can provide invaluable information about modern and ancient organisms. Burrowing activities of a population of deposit-feeding, freshwater Limnodrilus and Tubifex is found to produce biogenic graded bedding. Similarly, the burrowing activities of Euzonus mucronata are studied in relation to the trace fossil Macaronichnus segregatis, which displays mineralogical segregation between the burrow infill and mantle. The process of grain partitioning was assessed using videographic analyses of ingested and excreted grains by these deposit-feeding polychaetes, which selectively ingest felsic grains through en-masse feeding in felsic-rich locales. Macaronichnus is an important trace in ancient deposits of nearshore settings; however, since its inception, the genus had not been formally diagnosed. Accordingly, a unique approach to classification of these traces was undertaken, using grain sorting and collective morphology as ichnotaxobases, in addition to the diagnosis of a new, related genusHarenaparietis. In the Permian Snapper Point Formation of SE Australia, a new ichnospecies of Piscichnus was diagnosed and interpreted to reflect fish or cephalopod feeding via hydraulic jetting into the substrate in search of infaunal food sources. The delineation of trace fossils through ichnotaxonomy provides a basis for identifying trace fossil suites, which can be interpreted through ichnofacies analysis. Subtle ichnological and sedimentological attributes of deltaic strata in the Viking Formation permits the identification of wave-influenced and mixed river- and wave-influenced deposits in the Hamilton Lake and Wayne-Rosedale-Chain areas of Alberta, Canada, respectively. Facies analysis combined with the identification of palimpsest stratigraphic surfaces led to the identification of transgressively incised shoreface deposits at Hamilton Lake. Examples of palimpsest ichnofossils from the Hamilton Lake area and from other strata are used in an assessment of soft-, stiff- and firmground suites. This study revealed the importance of substrate properties, environment, stratigraphy and processes leading to the formation and expression of allocyclic and autocyclic surfaces.

No description available.