Antibacterial activity of coffee: Relationship between Biological Activity and Chemical Markers

The antibacterial activity of coffee depends mainly on the degree of roasting of the coffee beans. To
identify easily determinable chemical markers which relate to coffee's antibacterial activity,
5-caffeoylquinic acid, caffeic acid, nicotinic acid, trigonelline, 5-(hydroxymethyl)furfuraldehyde,t he
content of which changed throughout the roasting process, and caffeine were considered. A new
HPLC method that allows determination of these compounds simultaneously was developed. Two
antibacterial activity chemical markers were found: (1) the sum of trigonelline and nicotinic acid
contents and (2) the 5-caffeoylquinic acidcaffeine ratio.