Absorption, distribution and excretion of a functional foodstuff (Kureha M6271) derived from mycelia of a basidiomycete Tricholoma matsutake, after oral administration

To investigate the absorption, distribution, metabolism and excretion (ADME) profile of a functional foodstuff (Kureha M6271, herein after refereed to as CM6271), which was derived from mycelia of a basidiomycete Tricholoma matsutake BP-7304 strain, a 14C-labeled derivative (herein after refereed to as 14C-CM6271, specific radioactivity 16.7 kBq/mg) was prepared biosynthetically, and its absorption, distribution and excretion were examined after oral administration in rats. After oral administration of 14C-CM6271, it was rapidly absorbed via the intestinal tract and disappeared biphasically, showing a time course of blood radioactivities with the following pharmacokinetic (PK) parameters: t max=2.3 hr; C max=53.5 μg eq. of CM6271/mL; area under the curve (AUC) (0→∞)=1760 μg eq. of CM6271·hr/mL. After oral administration of 14C-CM6271, 3.2%, 61.3% and 29.0% of the radioactivities were excreted within 168 hours in urine, feces and breathings expired air, respectively; 93.5% of the total radioactivities were excreted externally 168 hours after administration. After oral administration of 14C-CM6271, radioactivities were distributed in the whole body. In the pancreas, harderian gland, submandibular gland, adrenal gland, liver and bone marrow, especially high radioactivities were distributed. Furthermore, in immune tissues such as mesenteric lymph nodes, thymus and spleen were distributed higher radioactivities compared to those in blood. Thus, it was revealed that 14C-CM6271 was rapidly absorbed and distributed in the whole body; most of the radioactivities were excreted within 168 hours, suggesting practically no accumulation in certain organs. (author)