I am also getting the same error from logs on a fresh install.
Running:
Jigoshop Version:1.13.1
WordPress Version:4.0.1
PHP 5.5.10
MySQL Version: 5.5.34
eAccelerator:Disabled
APC: Disabled
OpCache:Disabled
Never used this plugin before but my error occurs when trying to save any of the admin settings or add to cart button on the client side.
Thanks