Chlorogenic acid content swap during fruit maturation in Coffea pseudozanguebariae: Qualitative comparison with leaves

Chlorogenic acids (CGA) are products of phenylpropanoid metabolism, i.e. one branch of the phenolic pathway. A wild species, Coffea pseudozanguebariae, native of East Africa, is a caffeine-free species with low CGA content (1.2% dmb in green beans). It is also used as a gene donor to improve C. canephora cup taste quality. In the current study, contents of the different CGA isomers were observed during the development in fruits and leaves. In both organs, CGA content decreased strongly during the growth and feruloylquinic acids (FQA) constituted most CGA. In fruits, a critical step was emphasised at the growth end, beyond which caffeoylquinic acid content (CQA) drastically increased. Previous results on beans suggest that the qualitative change concerned seeds and not pulp. The breeding implications and potential for further studies are discussed.