Prophylactic effect of tea on pathogenic microorganism infections to humans and animals. (II). Protozoacidal effect on Toxoplasma gondii in vitro and mice.

The trophozoites of Toxoplasma gondii strain (RH) obtained from the peritoneal exudate of infected mice were treated with tea in various concentrations of 0.5, 1, 3 and 5% for 0.5, 1 and 3 hours, respectively. After treatment, they were intraperitoneally inoculated into the mice to observe the protozoacidal effect of tea. The results obtained are as follows: 1) Oolong tea and green tea had stronger protozoacidal effect than black tea. 2) The lowest and effective concentration of tea tested to kill Toxoplasma was 0.5%. 3) A half hour was not enough for tea in any concentration tested to kill the parasites completely. 4) Phosphate buffer solution and normal saline were unable to destroy the protozoa, but distilled water could destroy them like tea.