<?php
set_include_path('/your_path/');

require_once 'Zend/Loader/Autoloader.php';
Zend_Loader_Autoloader::getInstance();

$translator = new Zend_Translate(
    array(
        'adapter' => 'array',
        'content' => './languages',
        'locale' => 'pt_BR',
        'scan' => Zend_Translate::LOCALE_DIRECTORY
    )
);

var_dump($translator->getMessages('all'));