$ cat xyz.txt
mp ofile test._GDFS_Lookup.Lookup_ReRun "$AI_SERIAL_LOOKUP"'/rerun_lookup.dat'
mp ofile All_other_Setups.RPT_REQ_ID'file:'"$AI_SERIAL_LOOKUP"'/dtu_admin_test_lookup.dat'
$ awk -F"[ :]" '{print $NF}' xyz.txt
"$AI_SERIAL_LOOKUP"'/rerun_lookup.dat'
'"$AI_SERIAL_LOOKUP"'/dtu_admin_test_lookup.dat'