var xmlstring = '<?xml version="1.0"?>\
<root>\
	<data>\
		<row>\
			<cell>Captain</cell>\
			<cell>Bryophyllum</cell>\
			<cell>Zucchini</cell>\
		</row>\
	</data>\
</root>';
var xmlobject = (new DOMParser()).parseFromString(xmlstring, "text/xml");

var string = (new XMLSerializer()).serializeToString(xmlobject);
alert(string);