RESUMEN
A espécie Lippia gracilis SCHAUER (Verbenaceae) é nativa do Nordeste brasileiro e se destaca pela capacidade de acumular nos tricomas glandulares óleos essenciais com atividade antimicrobiana. Tendo em vista que não constam trabalhos na literatura sobre o estabelecimento in vitro dessa espécie, este trabalho teve como objetivo estabelecer protocolo para micropropagação de L. gracilis. Para tanto, ramos contendo folhas foram coletados de plantas matrizes no habitat natural para a confecção de estacas. Em laboratório, os explantes provenientes do processo de estaquia foram assepticamente tratados e inoculados em meio MS, acrescido de fitorreguladores, com o intuito de se estabelecer a melhor dose para o desenvolvimento dos explantes. Em decorrência de altos níveis de contaminação, avaliou-se o efeito da cefalexina. No entanto, apesar do antibiótico ter apresentado diminuição na contaminação bacteriana, a porcentagem de oxidação foi elevada. Portanto, testou-se o carvão ativado, ácido ascórbico, ácido cítrico e metade dos sais de MS quanto a eficiência no controle da oxidação. Concluiu-se que, o antibiótico na concentração utilizada provocou a oxidação dos explantes e os fitorreguladores, bem como os métodos antioxidantes testados, não apresentaram resultados consistentes para o melhor desenvolvimento dos explantes e controle da oxidação, respectivamente.
The species Lippia gracilis Schauer (Verbenaceae) is native to Northeastern Brazil and has been important for its ability to accumulate essential oils with antimicrobial activity in the glandular trichomes. Since there are no reports in the literature on the micropropagation of this species, the present work aimed to establish a protocol for L. gracilis micropropagation. Thus, branches containing leaves were collected from plant matrices in their natural habitat to prepare cuttings. In the laboratory, explants from cutting were aseptically treated and inoculated onto MS medium plus plant growth regulators in order to establish the best dose for the development of explants. Due to high levels of contamination, the effect of cephalexin was evaluated. Although the antibiotic decreased the bacterial contamination, the percentage of oxidation was high. Then, activated charcoal, ascorbic acid, citric acid and half the salts of MS were tested for their effectiveness to control oxidation. In conclusion, the used antibiotic concentration resulted in oxidation of explants. Furthermore, plant growth regulators and antioxidant methods did not show consistent results for a better development of explants and control of oxidation, respectively.
Asunto(s)
Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/embriología , Lippia/crecimiento & desarrollo , Guías como Asunto/métodos , Esterilizantes Químicos/administración & dosificación , Esterilizantes Químicos/inmunología , Aceites Volátiles/análisisRESUMEN
3-Monochloro-1,2-propanediol (MCPD) is a well-known by-product of acid-hydrolyzed soy sauce during its manufacturing process. To evaluate the immunotoxicity of MCPD, we investigated its effect on the thymic subset, delayed-type hypersensitivity, mixed-lymphocyte reaction and peritoneal macrophage activity. MCPD was administered by gavage for 14 days at 0, 25, 50, and 100 mg/kg/day to female Balb/c mice. The thymic subsets and annexin-V positive cells in thymic cells were quantified by flow cytometry. Mixed-lymphocyte reaction, delayed-type hypersensitivity and peritoneal macrophage activity were assessed. The mixed-lymphocyte reaction and delayed-type hypersensitivity were not significantly changed. However, there were significant increases in the apoptosis of mice treated with high dose of MCPD compared to the vehicle control. A significant decrease in the CD4+CD8+ thymic subset of mice treated with high dose of MCPD was observed. The activity of peritoneal macrophage was significantly reduced in high dose group. These results indicate that MCPD could modulate the immune function in Balb/c mice.