Biochemical and morphological responses to abiotc elicitor chitin in suspension-cultured sugarcane cells

Cells of Saccharum officinarum submitted to hydrolyzated chitin for 1 to 8h produced phenolic compounds. These alterations were observed through cytochemical methods using Toluidine Blue and Phloroglucinol/HCl. After 4 h, besides cell wall change, there was a change in nuclear pattern of chitin treated cells. There was a 96 percent increase in nuclear area in 6 h chitin treated material, as observed by Feulgen reaction. The treated cells showed chromatin compacted regions and a degeneration process of nucleoli. In the outer areas of cell wall, there was a polysaccharide desagregation, confirming results obtained for different plants with the use of other elicitors. Peroxidase activity was maximal after 4 h and decreased progressively. PAL activity started to increase at 4 h of incubation. These results showed that chitin hydrolyzate stimulated a defense response in sugarcane cells.

Células de Saccharum officinarum quando submetidas a quitina hidrolisada por 1 a 8h produziram material fenólico. Essas alterações foram observadas por meio de métodos citoquímicos como o Azul de Toluidina e Floroglucinol/HCl. Após 4 h, além das mudanças nas paredes celulares houve uma mudança no padrão nuclear das células tratadas com quitina. Por observação da reação de Feulgen, houve um aumento de 96 por cento na área nuclear no material em 6h. Para as células tratadas foram observadas regiões de cromatina compactada e um processo de degeneração do nucléolo. Nas áreas externas da parede celular existia uma desagregação dos polisacarídios confirmando os resultados obtidos para diferentes plantas com o uso de outros elicitores. A atividade da peroxidase foi maxima após 4 h e então decresceu progressivamente. A atividade da PAL aumentou a partir de 4 h de incubação. Estes resultados mostram que o hidrolisado de quitina estimula as respostas de defesa em células de cana.

Action of chemical agents in the process of in Vitro cell differentiation induced by microcrystalline collagen felt

The collagen used in the work as substratum has been divided into 3 groups: one under glutaraldehyde treatment, the second under periodate acid treatment, while the third remained non treated. The samples were removed after 1, 5, 10 and 15 days of growth to morphological analysis. The results led to the conclusion that both treated and non treated collagen felt induce a differentiation process distinguished by alterations in shape and size of cells and modifications in the protein-DNA complex, observed by Toluidine blue staining. The periodate acid acts on glicosidic portion of the collagen molecule and the cells that grow on this substratum have attachment and spreading changed, indicating that the lateral chains of carbohydrates of the collagen molecule exert influence on the attachment and spreading process of VERO cells, causing a partially changed cell proliferation