HYPOCHOLESTEROLEMIC EFFECT OF EUBACTERIUM COPROSTANOLIGENES ATCC-51222 IN RABBITS

Recently, a unique bacterium, Eubacterium coprostanoligenes ATCC 51222 , that reduces cholesterol to coprostanol was isolated. Because copros tanol is absorbed poorly, it was hypothesized that oral administration of Eu. coprostanoligenes might decrease cholesterol concentration in blood because the micro-organisms will decrease the absorption of endo genous and dietary cholesterol by conversion to coprostanol. To test t he hypothesis, three adult New Zealand White rabbits received 4 ml of Eu. coprostanoligenes suspension (ca 2 x 10(7) cells ml(-1)) daily per os for 10 d; three other adult New Zealand White rabbits received the same dosage of boiled bacterial suspension. Plasma cholesterol concen tration of experimental rabbits (183.3 +/- 11.0 mg dl(-1), mean +/- S. E.) was significantly lower (P < 0.001) than that of controls (248.8 /- 12.3 mg dl(-1), mean +/- S.E.). The coprostanol-to-cholesterol rati os in contents of digestive tracts of experimental rabbits were greate r than those of controls. The data indicate that oral administration o f Eu, coprostanoligenes caused a significant hypocholesterolemic effec t in rabbits and that this effect can be explained by the conversion o f cholesterol to coprostanol in the intestine.