You can recover individual messages from an Exchange database backup. The messages are recovered as PST files.
The method that you use to recover messages depends on how you performed the backup operation. You can perform most of the message recovery methods without first restoring the entire database.
Note: You can use Live Browse only with mailbox databases.
Any backup type
To restore data from an offline copy, restore the Exchange database out of place, and then recover the messages using the Restore offline DB messages option.
Block-level backup using the Exchange Database Agent
Recover messages from an Exchange database block-level backup.