“Chemical Composition Of Enzyme-Fractionated Aged Heart Tissue”, 1965-02 (; similar):
Fractionation of the enzyme-nonhydrolyzable constituents of human heart muscle from persons 64–74 years old resulted in separation of a fluorescing fraction, insoluble in anhydrous hydrogen fluoride, and containing 4.6% nitrogen (corresponding to 30% protein). This fraction was free from hydroxyproline and is therefore not derived from collagen.
An aromatic aldehyde was consistently separated when the enzymatically nonhydrolyzable fraction was broken down by destructive acid hydrolysis. Infrared data indicate a structure having characteristics in common with coenzyme Q.