$re = '/[:,] ([\w ]+) \</';
$str = 'From: aaa@aaa.com
CC: John Smith <aaa@aaa.com>, Charles <aaa@aaa.com>, Mary Lamb <aaa@aaa.com>, Chino <aaa@aaa.com>, Claudia <aaa@aaa.com>, <aaa@aaa.com>, <bbb@bbb.com>, John <aaa@aaa.com>
Hi there AAA! Hope you had a wonderful time
Best,
AAA';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php