Can we install Oracle 12c Database without using any Virtual Machine ? Currently I have installed it in VMWare Fusion but it is consuming a lot of power.
Oracle Database 12c doesn't run on OS X, so I guess you'll have to stick to a VM running a supported OS (see http://www.oracle.com/technetwork/database/enterprise-edition/downloads/index.html):
VM appears to be the only solution currently. You can attempt to dual boot your OS with a linux distribution, and install Oracle on that. I have only been able to install the instant client to get the SQL Developer to work on my OS X.
So something like this: /Library/Oracle/instantclient_11_2/network/admin/
on SQL Developer, you can then point the directory to the tnsnames.ora in this directory to get your connections..