Strange error messages in error_log file

I've been receiving these strange error messages recently. I've search forums, googled etc but nothing seems to be pointing me in the right direction. I'm pretty sure it's a plugin that's triggering examples of the following errors - I disabled the "global featured posts plugin" as I thought that might be the culprit but the error persist.

Any suggestions?

SELECT option_name, option_value FROM wp_88_options WHERE autoload = 'yes'
[wp-admin/includes/mu.php(1241): get_blogs_of_user()]
Table 'XXXX_wordpress.wp_88_options' doesn't exist

SELECT option_value FROM wp_88_options WHERE option_name = 'wp_88_user_roles' LIMIT 1
[wp-admin/includes/mu.php(1241): get_blogs_of_user()]
Table 'XXXX_wordpress.wp_88_options' doesn't exist

SELECT option_value FROM wp_88_options WHERE option_name = 'siteurl' LIMIT 1
[wp-admin/includes/mu.php(1241): get_blogs_of_user()]
Table 'XXXX_wordpress.wp_88_options' doesn't exist

SELECT option_value FROM wp_88_options WHERE option_name = 'post_count' LIMIT 1
[wp-admin/includes/mu.php(1241): get_blogs_of_user()]
Table 'XXXX_wordpress.wp_88_options' doesn't exist