Ive tried both examples, neither are working for me.

<script src="Scripts/jquery-1.7.1.min.js" type="text/javascript" />
    <script type="text/javascript">
        $(document).ready(function () {
            $('blockquote').removeclass();
            $('blockquote:before').removeclass();
            $('blockquote:after').removeclass();
            $('blockquote:hover').removeclass();
            $('p').removeclass();
            }
        });
</script>

    <script src="Scripts/jquery-1.7.1.min.js" type="text/javascript" />

    <script type="text/javascript">

        $(document).ready(function () {

            $('blockquote').removeClass();

            $('blockquote:before').removeClass();

            $('blockquote:after').removeClass();

            $('blockquote:hover').removeClass();

            $(p).each(function () {

                $(this).removeAttr("class");

            })

        });

    </script>