The board of trustees or governing board of any hospital or regional mental health center owned or owned and operated separately or jointly by the State of Mississippi or any of its branches, agencies, departments or subdivisions, or by one or more counties, cities, towns, supervisors districts or election districts, or combinations thereof, may authorize by resolution the organization and operation of, or the participation in, a group purchasing program with other hospitals or regional mental health centers, for the purchase of supplies, commodities and equipment when it appears to the board of trustees or governing board that such a group purchasing program could or would affect economy or efficiency in their operations. Purchases by hospitals or regional mental health centers participating in group purchasing programs of supplies, commodities and equipment through such programs shall be exempt from the provisions of Sections 31-7-9, 31-7-10, 31-7-11, 31-7-12 and 31-7-13.