Symphytum officinale L. (Boraginaceae) is a perennial herb known as comfrey, gum plant or boneset, and it is employed topically as anti-inflammatory, emollient and mild anesthetic in phytotherapy, due to allantoin found in the underground organs and leaf. In order to contribute to the medicinal plant and vegetal drug identification, morpho-anatomical investigations of the root and rhizome, in secondary growth, were carried out. The botanical material was fixed and prepared according to usual microtechniques. The underground organs are alike, slender and yellow to black coloured. The root and the rhizome show similar periderm and secondary vascular tissues, yet they differ in that the root shows exarch primary xylem, while the rhizome presents endarch primary xylem and parenchymatous pith. Numerous parenchymatic cells which contain mucilage and amyloplasts are observed in the root and rhizome.
Symphytum officinale; Boraginaceae; morpho-anatomy; rhizome; root
