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: In addition , maleate treatment reduced oxygen consumption in ADP - stimulated mitochondria and diminished respiratory control index when using malate / glutamate as substrate .
### Output Text:
In addition , <span class="chemical">maleate</span> treatment reduced <span class="chemical">oxygen</span> consumption in <span class="chemical">ADP</span> - stimulated mitochondria and diminished respiratory control index when using <span class="chemical">malate</span> / <span class="chemical">glutamate</span> as substrate . 