Tested in content types
Content-Type:application/rss+xml;
Content-Type:text/xml;
$url = 'https://domain.com/blog/?feed=rss2';
$feed1_xml = simplexml_load_file($url) or die("feed not loading");
To get the first post title
echo $feed1_xml->channel->item[0]->title;
To get the first post published date
echo $feed1_xml->channel->item[0]->pubDate
Returned date is in this format Wed, 20 Apr 2016 04:22:10 +0000
You can also convert it to ‘Y/m/d’
date('Y/m/d',strtotime($feed1_xml->channel->item[0]->pubDate));