the NaOH (base) WILL react.
The OH- ions cleave off the ions that are bonded harmalas (salts), giving you freebase harmalas.
I have never used a strong base when extracting harmalas, sodium carbonate always did the job for me. Id be careful about adding too much NaOH. Only add just enough to convert the harmalas to freebase.
Then you should be able to collect them as precipitate.
At high pH, around and above < 13.5, you'll dissociate the proton from the pyridine nitrogen, this causes problems. And usually ruins any hope of extracting actives.
Expect nothing, Receive everything.
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