RESUMEN
The soybean cultivar BR 36 with conventional levels of trypsin inhibitors activity and the soybean line BRM95-5262, which was genetically selected to contain low activity of trypsin inhibitors were used for biological assays with rats. BR 36 and BRM95-5262 contained 40 and 20, and 30 and 20% of relative residual activity of trypsin inhibitors, respectively. The mean values of PER and NPR showed that treatments with crude soybeans were minor than treatments with soybean thermically processed. However, the treatments of thermically processed soybean did not showed significative differences (p > or = 0.05). When the trypsin inhibitors activity were 8.61 and 8.44 UIT/mg of samples or 20 and 30% of relative residual activity of cultivar BR 36 and line BRM95-5262, respectively, it was observed that mean values of PER and NPR were not significatives. The mean values of CDA and CDV of treatments with crude soybeans were minor than treatment with casein and similar to the treatments with soybean thermically processed. So, it can be concluded that the biological evaluation obtained with soybean protein were dependent of initial trypsin inhibitors activities and of its respective thermical treatment. There was advantage in the use of BRM95-5262 soybean line with low trypsin inhibitors activity.