  Chiral phase transition is investigated in an $SU(3)_L \times SU(3)_R$
symmetric vector meson extended linear sigma model with additional constituent
quarks and Polyakov loops (extended Polyakov quark meson model). The
parameterization of the Lagrangian is done at zero temperature in a hybrid
approach, where the mesons are treated at tree-level, while the constituent
quarks at 1-loop level. The temperature and baryochemical potential dependence
of the two assumed scalar condensates are calculated from the hybrid 1-loop
level equations of states. The order of the phase transition along the $T=0$
and $\mu_B=0$ axes are determined for various parameterization scenarios. We
find that in order to have a first order phase transition at $T=0$ as a
function of $\mu_B$ a light isoscalar particle is needed.
