The bonds shall not be general obligations of the Department of Agriculture and Industries but shall be limited obligations payable solely from one or more specified sources, including, but not limited to, revenues derived from market charges, authorized under Section 2-5A-6, lease revenues, authorized under Section 2-5A-14, and appropriations made under Section 2-5A-15. The commissioner, with approval of the Board of Agriculture and Industries, may pledge all or any portion of such revenues as security for the payment of the bonds. All such pledges made by the commissioner shall take precedence in the order of the adoption of the resolutions containing the pledges. The commissioner may also obtain credit enhancement for the department’s bonds, including, but not limited to, bond insurance and letters of credit, and to pledge all or a portion of its revenues as security for its reimbursement obligations with respect thereto. All bonds issued by the Department of Agriculture and Industries pursuant to the provisions hereof shall be solely and exclusively obligations of the Department of Agriculture and Industries and shall not be an obligation or debt of the State of Alabama or any county or any municipality within the State of Alabama.