you can figure the stuff written past the year 1950 was produced by doctors/scientist/authors all for "hire" $$$$$$$$$ willing to write anything..
your key word is "standardized"
just reading anything written by such people is dealing with drug people, aka medical which are known for the past 100+ years to write anything to make the sell and always, always they seek the next new product for next year…..
book i replaces all the gimmics
otherwise, never use standardized extracted drugs/chemicals and only use the whole plant.