Publications by authors named "Tatiana M Souza-Moreira"

Friedelin, a pentacyclic triterpene found in the leaves of the Celastraceae species, demonstrates numerous biological activities and is a precursor of quinonemethide triterpenes, which are promising antitumoral agents. Friedelin is biosynthesized from the cyclization of 2,3-oxidosqualene, involving a series of rearrangements to form a ketone by deprotonation of the hydroxylated intermediate, without the aid of an oxidoreductase enzyme. Mutagenesis studies among oxidosqualene cyclases (OSCs) have demonstrated the influence of amino acid residues on rearrangements during substrate cyclization: loss of catalytic activity, stabilization, rearrangement control or specificity changing.

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Objective: The aim of this study was to investigate the functionality of ATC/TTC (Hap-1) and ATT/TTC (Hap-2) Interleukin (IL) 8 gene haplotypes in the response of neutrophils to Gram-negative bacteria associated with periodontitis.

Design: Neutrophils were isolated by gradient centrifugation from whole peripheral blood of systemically healthy individuals presenting the two IL8 gene haplotypes. Neutrophils were stimulated with P.

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spp., popularly known as "barbatimão", is the native Brazilian tree most often employed to treat wounds and infections. The aim of the present study was to highlight the importance of as well as other species recognized as "barbatimão", to human health, depicting the relevance of ethnopharmacological knowledge to scientific evidence for uses, related chemical compounds, development of pharmaceutical formulations, and the establishment of toxicity parameters.

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is a plant species with edible fruits but its chemical composition is not totally known yet although former studies showed its potential as antifungal agent. This work aimed the chemical analysis of the leaves, the activity against fungi species and evaluated cytotoxicity. Extract was obtained with 70% ethanol.

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A complexity of pathway expression in yeast compared to prokaryotes is the need for separate promoters and terminators for each gene expressed. Single transcript expression and separated protein production is possible via the use of 2A viral peptides, but detailed characterization to assess their suitability and applications is needed. The present work aimed to characterize multiple 2A peptide sequences to determine suitability for metabolic engineering applications in Saccharomyces cerevisiae.

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Triterpenes are interesting compounds because they play an important role in cell homeostasis and a wide variety exhibiting defense functions is produced by plant secondary metabolism. Those same plant secondary metabolites also exhibit biological properties with promising therapeutic potential as anti-inflammatory and antitumor agents. Friedelin is a triterpene ketone with anti-inflammatory and gastroprotective activities and it is a precursor of relevant antitumor quinonemethides.

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Peperomia obtusifolia, an ornamental plant from the Piperaceae family, accumulates a series of secondary metabolites with interesting biological properties. From a biosynthesis standpoint, this species produces several benzopyrans derived from orsellinic acid, which is a polyketide typically found in fungi. Additionally, the chiral benzopyrans were reported as racemic and/or as diastereomeric mixtures, which raises questions about the level of enzymatic control in the cyclization step for the formation of the 3,4-dihydro-2H-pyran moiety.

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Among the biologically active triterpenes, friedelin has the most-rearranged structure produced by the oxidosqualene cyclases and is the only one containing a cetonic group. In this study, we cloned and functionally characterized friedelin synthase and one cycloartenol synthase from Maytenus ilicifolia (Celastraceae). The complete coding sequences of these 2 genes were cloned from leaf mRNA, and their functions were characterized by heterologous expression in yeast.

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Lycopene is a carotenoid found in tomatoes with potent antioxidant activity. The aim of the study was to obtain an extract containing lycopene from four types of tomatoes, validate a quantification method for the extracts by HPLC, and assess its antioxidant activity. Results revealed that the tomatoes analyzed contained lycopene and antioxidant activity.

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Equisetum hyemale species is considered a medicinal plant used in the form of infusions to combat infectious or inflammation diseases and also diuretic effects, presenting several compounds related to these actions. In previous studies different species of Equisetum showed several phenolic compounds. The objective of this study was, for the first time, based on phytochemistry analysis to evaluate the antioxidant and antimicrobial activity.

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In addition to the bio-guided investigation of the antifungal activity of Plinia cauliflora leaves against different Candida species, the major aim of the present study was the search for targets on the fungal cell. The most active antifungal fraction was purified by chromatography and characterized by NMR and mass spectrometry. The antifungal activity was evaluated against five Candida strains according to referenced guidelines.

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Rhipicephalus sanguineus, commonly known as the brown dog tick, is one of the most widely distributed species of tick. In dogs, it can cause anemia and provide the transmission of pathogenic microorganisms such as Babesia canis, Ehrlichia canis, Hepatozoon canis, Anaplasma platys, and Mycoplasma haemocanis. To man, it can transmit the intracellular parasites Rickettsia rickettsii and Rickettsia conorii, the causative agents of the Rocky Mountain spotted fever in the Americas and Mediterranean and spotted fever in Europe and North Africa.

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Plinia cauliflora (Mart.) Kausel, widespread in South America, has edible fruits, and its bark is commonly used against diarrhea and other disorders, on account of its astringency. Because diarrhea is still one of the most important causes of illness and death among children in developing countries, where the population turns to traditional medicine for its treatment, the present study determined the composition of fruit and leaf extracts of P.

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The growing list of drug-resistant microorganisms and the persistence of deaths due to diarrhea are compelling reasons to study plants in search of new therapeutic agents. The chemical constitution and popular use of the edible fruits of Campomanesia xanthocarpa O. Berg motivated this study to assess the antimicrobial and antidiarrheal properties of the fruits.

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