In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: The heart tissue antioxidant enzymes such as superoxide dismutase , catalase , glutathione peroxidase , glutathione transferase and glutathione reductase activities , non - enzymic antioxidants such as cerruloplasmin , Vitamin C , Vitamin E and glutathione levels were altered in MI rats .
### Output Text:
The heart tissue antioxidant enzymes such as <span class="chemical">superoxide</span> dismutase , catalase , <span class="chemical">glutathione</span> peroxidase , <span class="chemical">glutathione</span> transferase and <span class="chemical">glutathione</span> reductase activities , non - enzymic antioxidants such as cerruloplasmin , <span class="chemical">Vitamin C</span> , <span class="chemical">Vitamin E</span> and <span class="chemical">glutathione</span> levels were altered in MI rats . 