PHARMACOKINETICS OF VINYLDITHIINS, TRANSFORMATION PRODUCTS OF ALLICIN

The pharmacokinetic behaviour of vinyldithiins, the main constituents of oily preparations of garlic (Allium sativum L.), was investigated a fter oral administration of 27 mg 2-vinyl-4H-1,3-dithiin and 9 mg 3-vi nyl-4H-1,2-dithiin to rats. In serum, kidney, and fat tissue, both vin yldithiins could be detected by GC-MS over a period of 24 h, whereas i n liver only 1, 3-vinyldithiin was found. Pharmacokinetic parameters ( t1/2, k(e), Cl(tot), AUC, and V(d)) were determined using compartment models, elucidating the different pharmacokinetic behaviour of both vi nyldithiins. 1,3-Vinyldithiin seems to be less lipophilic and is rapid ly eliminated from serum, kidney, and fat tissue, whereas 1,2-vinyldit hiin is more lipophilic and shows a tendency to accumulate in fat tiss ue. Experiments with liver homogenate confirmed the in vivo findings o n the different degradation rates of both vinyldithiins. Allicin, the precursor of the vinyldithiins, is metabolized more rapidly in liver h omogenate than the vinyldithiins.