"Has anybody heard of this? I read some data sheets which suggest this could be effective against protozoa and other parasites. Shroom"

Before WWII and the advent of antibiotics, licorice root was available in all pharmacies that I ever went too.  It was available without a prescription, though it was often suggested/prescribed by physicians for intestinal parasites.  My mother used to buy it for me before WWII and I personally bought it from a pharmacy as late as 1947.  It was in root/stick form, and you chewed on the stick.  It would last a long, long time and the more you chewed it (it stuck together, it didn't break off), the more flavor came out of it.

There are so many remedies that I remember from before WWII (pre antibiotics) that people just stare at you in disbelief if you mention them today.  Yes, we had many more ills during that era - typhoid, diphtheria, tuberculosis, polio, small pox, and on and on.  But we also had parents and grand parents who had some really good home remedies.