1. The Note 752322.1 has lots of tables that you can explore whether such tables are required to be purged and de-fragmented subsequently.

2. If you have never purged any tables, To start with, I suggest Run the query and pick the top 20 tables.

2.1 Top-20 list

select * from (

select SEGMENT_NAME "Table Name",sum(BLOCKS)  "Total blocks" , sum(bytes/1024/1024) "Size in MB" from dba_segments

group by segment_name

order by 2 desc)

where rownum < 20;

2.2 Refer Note 752322.1 to purge the tables listed above.

3. Most of the time FND_LOBS grown big. Explore whether FND_LOBS tables can be required to be purged and defragmented subsequently.

Refer the below note for more details.

Note.829235.1  FAQ - Performance considerations for FND_LOBS

Hope this helps!

Thanks

N Kandasamy