Recursive HiLight vs JQuery HiLight

hilight.js

    //RECURSIVE HI-LIGHT
    function highlight(word) {
        var matchExp = new RegExp(word, 'g');
        var highlightExp = '<span class="highlight">' + word + '</span>';
        var traverseDom = function(tree) {
            for (var i = 0; i < tree.children.length; i++) {
                var node = tree.children[i];
                traverseDom(node);
                tree.innerHTML = tree.innerHTML.replace(matchExp, highlightExp);
            }
        };
        traverseDom(document.body);
    }

    highlight('Lorem');

    //JQUERY HI-LIGHT
    function highlightJQ(word) {
        var matchExp = new RegExp(word, 'g');
        var highlightExp = '<span class="highlight">' + word + '</span>';
        $("*").each(function() {
            if ($(this).children().length == 0) {
                $(this).html($(this).html().replace(matchExp, highlightExp));
            }
        });
    }
    highlightJQ('ipsum');