1. Chemistry Department, Federal University of Viçosa, Viçosa 36570-900, MG, Brazil
2. Phytotechnics Department, Federal University of Viçosa, Viçosa 36570-900, MG, Brazil
3. Forest Engineer Department, Federal University of Viçosa, Viçosa 36570-900, MG, Brazil
4. Chemistry Department, Federal University of Minas Gerais, Belo Horizonte 31270-901, MG, Brazil