$re = '/ \(.*?\)/';
$str = 'icon-culture (2015_09_04 06_58_44 UTC).png
icon-disk (2015_09_04 06_58_44 UTC).png
icon-download (2015_09_04 06_58_44 UTC).png
icon-drop (2015_09_04 06_58_44 UTC).png
icon-file (2015_09_04 06_58_44 UTC).png
icon-film (2015_09_04 06_58_44 UTC).png
icon-flag (2015_09_04 06_58_44 UTC).png
icon-folder (2015_09_04 06_58_44 UTC).png
icon-garbage (2015_09_04 06_58_44 UTC).png
icon-graph (2015_09_04 06_58_44 UTC).png
icon-heart (2015_09_04 06_58_44 UTC).png
icon-help (2015_09_04 06_58_44 UTC).png
icon-lock (2015_09_04 06_58_44 UTC).png
icon-map (2015_09_04 06_58_44 UTC).png
icon-media (2015_09_04 06_58_44 UTC).png
icon-money (2015_09_04 06_58_44 UTC).png
icon-monitor (2015_09_04 06_58_44 UTC).png
icon-notes (2015_09_04 06_58_44 UTC).png
icon-openmail (2015_09_04 06_58_44 UTC).png
icon-phone (2015_09_04 06_58_44 UTC).png
icon-photo (2015_09_04 06_58_44 UTC).png';
$subst = "";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
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