Which two B vitamins are important in energy metabolism? What are their co-factor/co-enzyme forms? Describe their involvement in detail. Solution Metabolism: Metabolism is a term that is used to describe all chemical reactions involved in maintaining the living state of the cells and the organism. Many vitamins assists in the process of metabolism like B1, B2, B12, B3, B6, etc. Vitamin B1(Thiamine): Vitamin B2(Riboflavin):.