Trace for email notification in SOST transaction

Hi friends,

Please help me on the below issue,

In SRM system, whenever shopping card is approved, Automaticatly PO get generated and send a email notication to one partcular mail id simultaneouly.

I could see the email notification in SOST transaction.

Now my requirement is, I want to change the sender of that mail.

Now my issue is, I am not able to find, where and from which program, they are triggering this email.

Can you please help, how they are triggering this email. is there any way to find the sender program details based on the SOST message.

by deva