  We investigate the influence of the asymmetric quark matter (rho_u\ne
rho_d\ne rho_s) on the mass of the quasiparticles and the phase diagram of the
chiral quark model parametrized at one-loop level of the renormalized theory,
using the optimized perturbation theory for the resummation of the perturbative
series. The effect of various chemical potentials introduced in the grand
canonical ensemble is investigated with the method of relativistic many-body
theory. The temperature dependence of the topological susceptibility is
estimated with the help of the Witten-Veneziano mass formula.
