We have many customers doing so using the following techniques:
- Use our application plugin SDK to directly invoke into your backend applications
- Save emails and attachments to hot or magic folders that are then auto-imported into the document or content management system
- Convert emails or attachments into PDF or multi-page TIFF that are better suited to be understood by document or content management systems
- Use a custom script to integrate applications
For more: http://gearmage.com/blog/2016/06/14/extract-emails-integrate/
As always, contact us (firstname.lastname@example.org) if you have any product related questions.