There are no enzymes or anything that needs to "survive" in yeast nutrients.
They also really aren't necessary except in meads. Beer wort has all the nutrients it needs.
Cheers 
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Oh don't give me none more of that Old Janx Spirit
No, don't you give me none more of that Old Janx Spirit
For my head will fly, my tongue will lie, my eyes will fry and I may die
Won't you pour me one more of that sinful Old Janx Spirit
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