question about substrate

[hady2006]

hello ,
we use this equation to describe denitrification :
1,083CH₃OH + NO₃ → 0,065 C₅H₇O₂N + 0,758 HCO₃ +0,242 OH + 1,4 H₂O + 0,46 N₂
substrate (organic ) is CH₃OH and the product is biomass ( C₅H₇O₂N ) it is also organic
my question is about the difference between substrate and biomass and is C₅H₇O₂N a substrate ?

thanks for your help