Alice Sato

Influence of growth regulators in biomass production and volatile profile of in vitro plantlets of Thymus vulgaris L.

In vitro shoots of thyme (Thymus vulgaris L.) were established, and the effects of the auxin indole-3-acetic (IAA) acid and the cytokinins benzyladenine (BA), zeatin (ZEA), and kinetin (KIN) at 1.0, 5.0, and 10.0 microM on rooting, biomass production, and volatile compounds production by these plants were investigated. The volatiles were extracted by solid phase microextraction (SPME) and analyzed by gas chromatography. The highest biomass shoot growth was obtained with BA at 5.0 microM, while IAA at all concentrations tested achieved 100% rooting frequency. The three major compounds were gamma-terpinene (22.8-38.8%), p-cymene (13.8-27.9%), and thymol (6.5-29.0%). Quantitative changes of these compounds were observed in response to the effect of varying growth regulators concentrations in the culture medium. Growing Thymus vulgaris L. plants in media supplemented with IAA at 1.0 microM increased volatile compounds such as thymol by 315%. Nevertheless, the same major compounds were produced in all treatments and no qualitative changes were observed in the volatile profile of thyme plants.

The presence of concanavalin A and canatoxin in Canavalia ensiformis DC tissue culture

Isolated embryos, cotyledons and embryos plusa fragment of cotyledon from seeds of Canavalia ensiformis (jack bean) were cultured in vitro. Concanavalin A and canatoxin cross-reactive material were detected by double immunodiffusion tests. Canatoxin was detectable until 30 days in cultures of embryos, embryos plus cotyledons and hypocotyls. Concanavalin A was also present in all cultures being detected until 90 days in cultures treated with 6-benzylaminopurine. No concanavalin A was detected in root cultures. Concanavalin A was present in cell suspensions until 45 days of culture; the culture medium contained neither concanavalin A nor canatoxin. Tissue cultures thus can produce Con A and CNTX and will be an important research tool for studying the biosynthesis of such substances.

Eugenia neonitida Sobral and Eugenia rotundifolia Casar. (Myrtaceae) essential oils: composition, seasonality influence, antioxidant activity and leaf histochemistry

Investigou-se a influencia da sazonalidade na composicao do oleo essencial de folhas frescas de Eugenia neonitida Sobral e Eugenia rotundifolia Casar. (Myrtaceae) coletadas trimestralmente, assim como a atividade antioxidante do oleo essencial de folhas secas e a histoquimica foliar. Os componentes majoritarios do oleo essencial de E. neonitida foram biciclogermacreno, germacreno D e β-cariofileno e os de E. rotundifolia foram n, β-pineno e β-cariofileno. Os oleos essenciais de ambas as especies apresentaram principalmente hidrocarbonetos e alcoois ciclicos, sendo o oleo essencial de E. neonitida composto principalmente por sesquiterpenos e o de E. rotundifolia por monoterpenos. A precipitacao parece influenciar na composicao dos oleos essenciais de ambas as especies. O oleo essencial de folhas secas apresentou baixa atividade antioxidante. Os testes histoquimicos evidenciaram que as cavidades secretoras armazenam solucoes complexas e contem, alem dos oleos essenciais, outras classes de lipideos.

Solasodine accumulation in regenerated plants of Solanum torvum Sw

RESUMO: Acumulo de solasodina em plantas micropropagadas de Solanum torvum Sw. A regeneracao de Solanum torvum e a avaliacao do conteudo de solasodina foram os objetivos de cultura de segmentos nodais. A influencia de auxinas (acido 3-indolacetico, acido naftalenoacetico) e de 6-benzilaminopurina no crescimento de S. torvum na micropropagacao foi investigado. Cultura de segmentos nodais foi iniciada por sementes germinadas em meio basico MS acrescido de GA 3 e cultivadas em diferentes concentracoes de AIA, AIA + BAP e ANA + BAP. Plantas da cultura in vitro com 60 dias foram coletadas, congeladas e liofilizadas e o metodo de alaranjado de metila foi utilizado para quantificacao de solasodina para o ensaio espectrofotometrico. Os melhores resultados para regeneracao vegetal e acumulo de solasodina foram alcancados no meio MS sem adicao de reguladores de crescimento havendo, porem grande producao de calos de base friaveis. Esses resultados mostram que a partir desses calos, cultura de celulas pode ser iniciada com aplicacao de outras auxinas e citocininas para o aumento da producao de solasodina alem de diferentes eliciadores, intensidades luminosas e concentracoes de sacarose. Palavras-chave: Solanaceae, jurubeba, auxina, citocinina, alcaloide esteroidal