title: How to improve this regex to avoid PREG_BACKTRACK_LIMIT_ERROR?
body: <p>I have following regex.</p>
  
  <pre><code>(From:.*)&lt;(.+) (.+)@first abc.com&gt;
  </code></pre>
  
  <p>And I am using following code to parse email address</p>
  
  <pre><code>$mimeFile = preg_replace_callback( "/(From:.*)&lt;(.+) (.+)@first abc.com&gt;/", 
  function($matches) { 
      return $matches[1].'&lt;'.strtolower($matches[2]).'.'.strtolower($matches[3]).'@xyz.com&gt;'; 
  }, $content );
  </code></pre>
  
  <p>It works for small content, but when content is large, it gives a PREG_BACKTRACK_LIMIT_ERROR.</p>
  
  <p>How can I improve my regex?</p>
  
  <p>Thanks in advance.</p>