Bismillahirrahmanirrahim.

gsettings set org.gnome.gnome-screenshot auto-save-directory ‘/media/ubuntu/Dua/Bahan/Naskah’

Referensi

1. http://askubuntu.com/questions/463862/change-gnome-screenshot-auto-save-directory-in-ubuntu-gnome-14-04
2. http://askubuntu.com/questions/114429/default-save-directory-for-gnome-screenshot