This question should (ideally) be answered by scientists familiar with
the absorption and pharmacokinetics of orally administered Coenzyme
Q10 supplements (ubiquinone.)  Based on its lipid nature and its lack
of aqueous solubility, what is the fastest possible time from time of
ingestion for its appearance in the blood?

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Request for Question Clarification by livioflores-ga on 12 Jun 2005 00:50 PDT

This is what I found:

"Pharmacokinetics
[1], [2]  Absorption:
Uptake of dietary CoQ in the liver does not affect the synthesis of
endogenous CoQ, which supports the notion that CoQ does not exert any
feedback inhibition on its own biosynthesis. Animal studies
demonstrate a bioavailability of 2-3%. With high doses of dietary CoQ,
the blood concentration in both rats and humans can be increased about
2- to 4-fold. Following ingestion of 100 mg of CoQ, peak plasma levels
occur between 5 and 10 hours. Tmax is approximately 6.5 hours, which
indicates slow absorption from the GI tract possibly due to the high
molecular weight and low water solubility of CoQ.
Distribution:
The mean plasma levels after a single 100 mg oral dose of CoQ in human
subjects is 1.004+/- .37 mg/mL. In humans, CoQ is found in relatively
high concentrations in the heart, liver, kidney, and pancreas. The
plasma half-life of CoQ in different tissues varies between 49-125
hours. Following absorption from the GI tract, CoQ is taken up by
chylomicrons. The major portion of an exogenous dose of CoQ is
deposited in the liver and packaged into VLDL lipoprotein.
Metabolism/Excretion:
It is assumed that metabolism and excretion of exogenous CoQ is
analogous to endogenously produced CoQ. The excretion of CoQ is
predominantly via the biliary tract."
From "Coenzyme Q10" by Barrie Cassileth and K. Simon Yeung:
http://www.brainlife.org/fulltext/cassileth_q102002.htm


"Pharmacokinetics
CoQ10 is absorbed slowly. Peak plasma levels are attained within 5?10
hours following oral administration. Absorption is dependent on the
presence of fat in the gastrointestinal tract. After absorption, CoQ10
is initially sequestered by chylomicrons and then distributed to the
liver to be incorporated into very low density lipoproteins (VLDL).
The metabolic fate of CoQ10 has not been fully elucidated. The
elimination half-life of the parent compound is approximately 34
hours; excretion is primarily through the biliary tract and over 60%
of the oral dose is recovered in the feces."
From "Coenzyme Q10, A Review of Essential Functions and Clinical
Trials" by Caroline Fuke, Pharm.D. - Pharmacist, Long?s Pharmacy,
Honolulu, HI:
http://www.healingedge.net/store/page243.html

Is the above sufficient for an answer?

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Clarification of Question by saregamapa-ga on 12 Jun 2005 14:45 PDT

No.  I need to know, based on the site(s) of absorption (of CoQ10) in
the gut and the route it takes after passage from the gut to the
lymphatics and so forth,   what the shortest time period you would
expect the orally ingested CoQ10 to first show up in the blood.