How to get better throughput in xbee3?

I have done the throughput testing using the xbee3 modules, I am getting maximum only 7.7kbps throughput.

How can I achieve more throughput?
Is there any parameter which i need to set to get better throughput?

What firmware version are you working with? What settings are you using?

Firmware Version 100B.
I am using in API 1 mode, encryption enabled, encryption option 2 Bitfield.

With encryption enabled, that sounds about right on a Zigbee mesh network.

So how to disable mesh and use another mode to get better throughput?

You need to install different firmware on the modules. Something like the 802.15.4 code.