how to fetch image path from description element in RSS

Hello Sir I am trying to fetch image path from amazon RSS feeds but there are 3 different images in the description tag...I am using DOMDocument method to fetch data from RSS feeds ...When i am trying to fetch the image path its fetching the complete description(all 3 images path in one), but i only need 1st main image path to show it in my RSS feed slider... need help badly ...last date of project submission ...Thanks in advanced

Amazon RSS feed -- http://www.amazon.co.uk/gp/rss/bestsellers/electronics/560834/ref=zg_bs_560834_rsslink

And Here is my test code to check images are working or not

error_reporting(0);
$rss = new DOMDocument();
$rss->load('http://www.amazon.co.uk/gp/rss/bestsellers/electronics/560834/ref=zg_bs_560834_rsslink');
  $feed = array();
        foreach ($rss->getElementsByTagName('item') as $node) {
        $item = array ( 
         'title' => $node->getElementsByTagName('title')->item(0)->nodeValue,
         'desc' => $node->getElementsByTagName('description')->item(0)->nodeValue,
         'link' => $node->getElementsByTagName('link')->item(0)->nodeValue,
         'date' => $node->getElementsByTagName('pubDate')->item(0)->nodeValue,
          'img' => $node->getElementsByTagName('description')->item(1)->getAttribute('src')
         );
        array_push($feed, $item);
        }   
        $limit = 10;        
    for($x=0;$x<$limit;$x++) {
        $title = str_replace(' & ', ' &amp; ', $feed[$x]['title']);
        $link = $feed[$x]['link'];
        $description = $feed[$x]['desc'];
        $img = $feed[$x]['img'];    
        $date = date('l F d, Y', strtotime($feed[$x]['date'])); 

    echo $img;
    echo "<hr/>";
    }