Levels of pyrroloquinoline quinone in various foods
Keyword(s):
The levels of free pyrroloquinoline quinone (PQQ) in various foods were examined by the use of gas chromatography-mass spectrometry. PQQ was extracted from the samples, after addition of [U-13C]PQQ as internal standard, with n-butanol and Sep-Pak C18 cartridges. After derivatization of PQQ with phenyltrimethylammonium hydroxide, molecular peaks at m/z 448 and 462 were used for detection of PQQ and [U-13C]PQQ respectively, by selected ion monitoring. Free PQQ could be detected in every sample in the range 3.7-61 ng/g or ng/ml. Since its levels in human tissues and body fluids are 5-10 times lower than those found in foods, it is probable that PQQ existing in human tissues is derived, at least partly, from the diet.
1994 ◽
Vol 662
(1)
◽
pp. 123-127
◽
1994 ◽
Vol 77
(4)
◽
pp. 917-924
◽
1979 ◽
Vol 164
(3)
◽
pp. 386-393
◽
1980 ◽
Vol 7
(9)
◽
pp. 372-376
◽