$re = '/[a-zA-z]+[.]+[a-zA-z]*[@]eil.co.in/m';
$str = ' "ABHAY KUMAR" <abhay.kumar@eil.co.in>, "JATINDER S DUGGAL" <js.duggal@eil.co.in>, "MAHESH EASWARAN" <mahesh.easwaran@eil.co.in>, "MAHESH GUPTA" <mahesh.gupta@eil.co.in>, "MUKESH KUMAR" <mukesh.kumar@eil.co.in>, "anand yadav" <anand.yadav@eil.co.in>, "SANJIT KUMAR KESHRI" <sanjit.keshri@eil.co.in>, "PINTU LAL" <pintu.lal@eil.co.in>, "SUSHANT CHANDRA SAXENA" <sushant.saxena@eil.co.in>, "VIKAS VIKAS" <vikask@eil.co.in>, "PRINCE PRINCE" <prince.gupta@eil.co.in>
Cc: "NALIN KUMAR" <kumar.nalin@eil.co.in>';
preg_match_all($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