A comparative study of tannin concentration in three medicinal plants from caatinga vegetation (Northeast Brazil) was carried out through colorimetric assays. Bark and leaf samples of 10 individuals of each species were extracted with 80% methanol. Tannin was determined by Folin-Ciocalteau analysis for total phenolic materials, followed by precipitation with casein. Additionally, it was tested the hypothesis that the tannin concentration is directly related with the height and diameter of the plants. The results show that the studied species contain an expressive amount of tannins.
Caatinga; tannins; Anadenanthera colubrina; Caesalpinia pyramidalis; Myracrodruon urundeuv
