There are no enzymes that can change alcohol into gasoline. Sorry.
There is a process available:)
Mix water with the alcohol tainted fuel, let stand, titrate.
You may have to add octane enhancers. Using the middle grade gas negates that need.
Don’t drink the water alcohol mix.
There are no enzymes that can change alcohol into gasoline. Sorry.= = =
How about I do my own 15% ethanol.
Say I buy 10 gallons gasoline (non-ethonal in my fantasy).
Then, to make the 15%, I buy 1.5 gallons of alcohol.
Beer, wine, hard stuff, whatever.
If I am judicious, I can drink it by the time those 10 gallons are used up.
Probably not a good idea to use both at the same time.