Within chiral perturbation theory at the quark level (CHPT)q with line
ar realization of chiral U(3)XU(3) symmetry the new low-energy AP3-int
eraction, produced by convergent box-constituent-quark-loop diagrams,
is obtained, and its contributions to processes of low-energy interact
ions of low-lying mesons are investigated. The new interaction goes be
yond the framework of the low-energy current algebra approach and effe
ctive chiral Lagrangians with linear realization of chiral symmetry, c
onstructed at the hadronic level.