Whether IOS9.1 beta cannot be updated to this IOS9?

The only way to go back to the public release in this case is to restore to a backup before you installed the beta profile. For example, if your 5s came with IOS 8 and you made an iCloud backup before installing the public beta, you'll need to:
1. go to settings, iCloud, and turn off find my iPhone.
2. connect your phone to your computer.
3. hold down home and power for about 10 to 12 seconds until you hear the disconnect and connect sound, and iTunes should come up letting you know your phone is in recovery mode.
4. press the restore button in iTunes
5. The file should download, and after it's done your phone should reboot.
6. press the home button once, wait a couple of seconds, then click the home button 3 times quickly, and voiceover should come on.
7. Choose your language and country, enable location services, and join your wifi network.
8. You will be prompted to setup as new, restore from itunes backup or iCloud backup. If you made a backup to iTunes or iCloud, you will either have to continue in iTunes on your computer or, after choosing restore from iCloud, sign in with your id and password, and choose the backup mad at the time before you installed the beta.

I hope I'm not overstepping any lines here, but I had the exact same issues and had to do it through trial and error myself. Let me know if you need more explanation of any of the steps, I'm not sure how familiar you are with the process.