Is it possible to call the member function of another controller in zend framework, if yes then how?
Controllers aren't designed to be used in that way. If you want to execute an action of the other controller after your current controller, use the _forward() method:
// Invokes SecondController::otherActionAction() after the current action has been finished.
$this->_forward('other-action', 'second');
Note that this only works for action methods (“memberAction”), not arbitrary member functions!
If SecondController::memberFunction() does something that is needed across multiple controllers, put that code in a action helper or library class, so that both controllers can access the shared functionality without having to depend on each other.