  The entropic and information inequalities for two qubit X-states transformed
by the nonlinear channels are given in explicit form. The subadditivity
condition and nonnegativity of von Neumann quantum information are studied for
both initial X-state and the state after action of the nonlinear channel.
Partial case of Werner state is considered in detail. We shown that the von
Neumann information increases due to action of the nonlinear channel. We
generalize the results obtained for Werner state in our earlier article [J.
Russ. Laser Res., \textbf{35}, iss. 3 (2014)] to the case of X-state of two
qubit system. We study the influence of nonlinear channel acting on X-state of
two qubit system onto von Neumann mutual information.
