**A Comparative Study of the Chelating Effect Between Textured Soya Aqueous Extract and EDTA on Fe3+ , Pb2+, Hg2+, Cd2+ and Ni2+ Ions**

Guajardo Jesús, Morales Elpidio, López Francisco, Quintero Cristina, Compean Martha, Noriega María-Eugenia, González Jesús and Ruiz Facundo *Universidad Autónoma de San Luis Potosí Mexico* 
