- strstr: documentation ( source)
<?php
$email = "404:Not Found(CLIENT_ERROR):Product with ref '47493470' does not exist";
$domain = strstr($email, '404:Not Found(CLIENT_ERROR):Product with ref ');
echo $domain; // Affiche : @example.com
$user = strstr($email, '@', true); // Depuis PHP 5.3.0
echo $user; // Affiche : name