Last modified post from all post types

Hi,
I am trying to get date of last modified post from all post types. I can get last post from accurate post type.

.../api/get_posts/?orderby=modified&order=desc&json_unescaped_unicode=utf-8&post_type=produkty

Can I get array of all posts from all post types?
Thanks for help.

https://wordpress.org/plugins/json-api/