Tree crown variation and seasonal in the phenolic compounds content of Stryphnodendron adstringens (Mart) coville leaves

Abstract

The aim of this study was to compare phenolic compounds contents between different positions within the crown and between collection periods, and to evaluate the tannin contents by the Folin-Ciocalteu method. The collections were performed in Lavras, in the southern region of the Brazilian state Minas Gerais. The experiment was conducted in a completely randomized design (factorial 3 × 4); the first factor being the position (base, middle, top); and the months, the second factor (February, May, September and December). We verified that the leaves of S. adstringens present higher total phenolic and tannin contents at the top (23.05% and 18.23%) and base (21.42% and 16.61%) of the crown, in May (25.79% and 20.85%) and September (25.57% and 20.50%), respectively. There was no difference in the residual phenol and flavonoid contents between the positions within the crown or in the months of collection. These facts suggest that within the crown and climatic changes may be one of the factors affecting phenol levels in Stryphnodendron adstringens.