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 protective role of mangiferin was analyzed by triphenyl tetrazolium chloride ( TTC ) test used for macroscopic enzyme mapping assay of the ischemic myocardium .
### Output Text:
The protective role of <span class="chemical">mangiferin</span> was analyzed by <span class="chemical">triphenyl tetrazolium chloride</span> ( <span class="chemical">TTC</span> ) test used for macroscopic enzyme mapping assay of the ischemic myocardium . 