[jbj]

not only uracil and niacin, also other molecules:

'''revealing that a wide range of organic compounds such as racemic non-protein type amino acids, alkylamines, carboxylic acids, polycyclic aromatic hydrocarbons (PAHs), and nitrogen heterocyclic molecules are present in the aqueous or organic extracts'''

from the linked paper.

racemic mix refers to the equal amout of stereoisomers