Display profile field within BP Nouveau using the template hierarchy. Put the following into a /buddypress/members/ subfolder of your theme and replace `Name of your xProfile field` with the name of your profile field :)

members-loop.php

<?php
/**
 * BuddyPress - Members Loop
 *
 * @since 3.0.0
 * @version 3.0.0
 */

bp_nouveau_before_loop(); ?>

<?php if ( bp_get_current_member_type() ) : ?>
	<p class="current-member-type"><?php bp_current_member_type_message(); ?></p>
<?php endif; ?>

<?php if ( bp_has_members( bp_ajax_querystring( 'members' ) ) ) : ?>

	<?php bp_nouveau_pagination( 'top' ); ?>

	<ul id="members-list" class="<?php bp_nouveau_loop_classes(); ?>">

	<?php while ( bp_members() ) : bp_the_member(); ?>

		<li <?php bp_member_class( array( 'item-entry' ) ); ?> data-bp-item-id="<?php bp_member_user_id(); ?>" data-bp-item-component="members">
			<div class="list-wrap">

				<div class="item-avatar">
					<a href="<?php bp_member_permalink(); ?>"><?php bp_member_avatar( bp_nouveau_avatar_args() ); ?></a>
				</div>

				<div class="item">

					<div class="item-block">

						<h2 class="list-title member-name">
							<a href="<?php bp_member_permalink(); ?>"><?php bp_member_name(); ?></a>
						</h2>

						<?php if ( bp_nouveau_member_has_meta() ) : ?>
							<p class="item-meta last-activity">
								<?php bp_nouveau_member_meta(); ?>
							</p><!-- #item-meta -->
						<?php endif; ?>

						<div style="clear: both;">
							<?php bp_member_profile_data( 'field=Name of your xProfile field' ); ?>
						</div>

						<?php
						bp_nouveau_members_loop_buttons(
							array(
								'container'      => 'ul',
								'button_element' => 'button',
							)
						);
						?>

					</div>

					<?php if ( bp_get_member_latest_update() && ! bp_nouveau_loop_is_grid() ) : ?>
						<div class="user-update">
							<p class="update"> <?php bp_member_latest_update(); ?></p>
						</div>
					<?php endif; ?>

				</div><!-- // .item -->

			</div>
		</li>

	<?php endwhile; ?>

	</ul>

	<?php bp_nouveau_pagination( 'bottom' ); ?>

<?php
else :

	bp_nouveau_user_feedback( 'members-loop-none' );

endif;
?>

<?php bp_nouveau_after_loop(); ?>