用于从数组中获取数据的正则表达式

I have the following data in my table column information

array( 'Email: Customer One <customer1@yahoo.com>. By employee: james@company.com.',
    'By employee: james@company.com. Department Head: Nickolas Jim.',
    'Email: Customer One <customer2@yahoo.com>. Status: currently employees.',
    'Email: Customer One <customer3@yahoo.com>. By employee: Mirza@company.com.'
)

Etc, etc

I have a need to get the 'By employee' from the array. In other words I am in a need of regex solution

ED. I just need the By employee if present..nothing else So in above example I will have

By employee: james@company.com
By employee: james@company.com
By employee: Mirza@company.com

I have tested following sample code in php 5.4.5:

    <?php
$foo = array( 'Email: Customer One <customer1@yahoo.com>. By employee: james@company.com.',
              'By employee: james@company.com. Department Head: Nickolas Jim.',
              'Email: Customer One <customer2@yahoo.com>. Status: currently employees.',
              'Email: Customer One <customer3@yahoo.com>. By employee: Mirza@company.com.'
            );

for($i = 0; $i < count($foo); ++$i){
    if(0 >= preg_match('/\bBy employee: ([-\w._]+@[-\w]+(?:\.[-\w]+)*\.\w{2,4})\b/', $foo[$i], $matches))
        continue;  

    echo $matches[0] . "
";
    echo $matches[1] . "
";
    echo "
";  
}            

?>

output:

        By employee: james@company.com
james@company.com

By employee: james@company.com
james@company.com

By employee: Mirza@company.com
Mirza@company.com