Telma Alves Garcia

Production of laccase by Pynoporus sanguineus using 2,5 - Xylidine and ethanol

Enzyme application in biotechnological and environmental processes has had increasing interest due to its efficiency, selectivity and mainly for being environmentally healthful, but these applications require a great volume of enzymes. In this work the effect of different concentrations of ethanol and 2,5-xylidine on growth and production of laccase by Pycnoporus sanguineus was investigated. In a medium containing 200 mg.L-1 of 2,5-xylidine or 50 g.L-1 of ethanol, the maximum activity of laccase was 2019 U.L-1 and 1035 U.L-1, respectively. No direct correlation between biomass and activity of laccase was observed for any of the inducers used during the tests. Ethanol concentrations, larger than or equal to 20 g.L-1, inhibited the radial growth of P. sanguineus. This study showed that ethanol, which has less toxicity and cost than the majority of the studied inducers, presents promising perspectives for laccase production by P. sanguineus.

Production and characterization of tyrosinase activity in Pycnoporus sanguineus CCT-4518 crude extract

Tyrosinase is an enzyme of industrial interest. The production and characterization of tyrosinase from P. sanguineus CCT-4518 were investigated. The selection of inductors, luminosity influence, inoculum size and type of culture medium on the production of tyrosinase and the effect of inhibitors on enzyme activity were performed. Optimum conditions for intracellular tyrosinase production was observed after 2 days using 0.15% L-tyrosine as inducer, in the presence of light, with inoculum size of 10 mycelium discs, using 2% malt extract broth medium, incubated at 30°C, and constant agitation of 150 rpm. Tyrosinase activity was completely inhibited by the addition of 6 mM salicylhydroxamic acid or phenylthiourea, however an inhibition of 4.15% was recorded by the addition of 0.1 mM sodium azide. No inhibition could be detected in case of 0.1 mM phenyl methanesulfonyl fluoride addition. Optimal conditions for intracellular tyrosinase activity using L-dopa as substrate were observed at pH 6.6 and 45°C. Thermal stability studies indicated that the enzyme is stable at 45°C for 15 minutes. Higher temperatures decreased tyrosinase activity. Enzyme production was confirmed by non-denaturing polyacrylamide gel electrophoresis and the protein profile was investigated by denaturing polyacrylamide gel electrophoresis.

Electroanalysis and laccase-based biosensor on the determination of phenolic content and antioxidant power of honey samples

Honey is a functional food widely consumed. Thus, the evaluation of honey samples to determine its phenolic content and antioxidant capacity (AOC) is relevant to determine its quality. Usually AOC is performed by spectrophotometric methods, which lacks reproducibility and practicality. In this context, the electroanalytical methods offer higher simplicity and accuracy. Hence, the aim of this work was to use of electroanalytical tools and laccase based biosensor on the evaluation of AOC and total phenol content (TPC) of honey samples from different countries. The antioxidant power established by electrochemical index presented good correlation with the spectrophotometric FRAP (Ferric Reducing Ability of Plasma) and DPPH (2,2-Diphenyl-1-Picrylhydrazyl) radical scavenging assays. Also, TPC results obtained by the biosensor agreed with the Folin-Ciocalteu (FC) assay. In addition to the semi quantitative results, the electroanalysis offered qualitative parameters, which were useful to indicate the nature of major phenolic compounds.

Pesquisa de Listeria Monocytogenes em Queijos Fatiados Comercializados em Estabelecimentos Varejistas Na Cidade de Goiânia

Ana Clara Melo Lima, Luiza Chaul Toubas, Ieda Maria Sapateiro Torres, Telma Alves Garcia, Virgínia Farias Alves.Pesquisa de Listeria Monocytogenes em Queijos Fatiados Comercializados em Estabelecimentos Varejistas Na Cidade de Goiânia. In: Anais do 12o Congresso Latinoamericano de Microbiologia e Higiene de Alimentos MICROAL 2014 [= Blucher Food Science Proceedings, num.1, vol.1]. São Paulo: Editora Blucher, 2014. DOI 10.5151/foodsci-microal-112 Pesquisa de Listeria monocytogenes em Queijos Fatiados Comercializados em Estabelecimentos Varejistas Na Cidade de Goiânia

Momentos de avaliação e movimentos de mudança em um curso de Farmácia

Os processos avaliativos do curso de graduacao em farmacia da Universidade Federal de Goias se iniciaram a partir do Programa de Avaliacao Institucional das Universidades Brasileiras (PAIUB). Em seu percurso, tem sido empregadas diferentes metodologias visando a evolucao do processo e a agregacao de diferentes olhares que, ao longo do tempo, vem contribuindo para a busca da excelencia do curso. Considerando concepcoes e enfoques de estudantes, professores, servidores tecnico-administrativos e especialistas em avaliacao, foi possivel vislumbrar mudancas que progressivamente vem permeando o curso. As possibilidades e expectativas apontam para a incorporacao de novas vivencias por parte dos docentes, com praticas pedagogicas diversificadas, bem como dos estudantes, com novas relacoes sociais.