Cashew tree (Anacardium occidentale L.)belongs to the botanical family Anacardiaceae, this one consisting of 60-80 genera and about 600 species distributed pantropically, but with a few genera in northern temperate regions and native to the semi-arid coasts of Brazil. This family presents resinous trees, shrubs and climbers. This resin is synthesized in the epithelial cells lining pockets or canals and then secreted into these internal cavities. Synthesis generally occurs in all organs of the plant, with different quantitative composition; appearing to be genetically controlled and little influenced by environmental conditions. The gum is similar to gum arabic and may be used as to a substitute for liquid glue for paper, in the pharmaceutical cosmetic industry and as an agglutinant for capsules and pills. The use of natural gums, taken from the exudates and extracts of plants, have been given a strong impulse due to the many and lucrative possibilities for industrialization and to the excellent international market. By natural exudation or by means of incisions, a gum or resin of a yellowish color, soluble in water. In the present work, we studied the resin/gum secretory ducts that appear along the cashew tree bark, using hystological procedures and microscopic observations. The gum was studied at its crude state and then chemically treated (insolubilization process) in order to obtain a kind of gel (microbiofilm). Besides the chemical composition proteins, lipids, sugars, fibers and ashes), it was studied the gum’s electric conductivity, searching for a possible use as a biosensor for plant proteins.

Key words: Anacardiaceae, biological characterization, cashew-tree, exudate gum, phytochemical compounds, secretory ducts